• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- PPCISelLowering.cpp - PPC DAG Lowering Implementation -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the PPCISelLowering class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "PPCISelLowering.h"
15 #include "PPCMachineFunctionInfo.h"
16 #include "PPCPerfectShuffle.h"
17 #include "PPCTargetMachine.h"
18 #include "MCTargetDesc/PPCPredicates.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/VectorExtras.h"
21 #include "llvm/CodeGen/CallingConvLower.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineInstrBuilder.h"
25 #include "llvm/CodeGen/MachineRegisterInfo.h"
26 #include "llvm/CodeGen/PseudoSourceValue.h"
27 #include "llvm/CodeGen/SelectionDAG.h"
28 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
29 #include "llvm/CallingConv.h"
30 #include "llvm/Constants.h"
31 #include "llvm/Function.h"
32 #include "llvm/Intrinsics.h"
33 #include "llvm/Support/MathExtras.h"
34 #include "llvm/Target/TargetOptions.h"
35 #include "llvm/Support/CommandLine.h"
36 #include "llvm/Support/ErrorHandling.h"
37 #include "llvm/Support/raw_ostream.h"
38 #include "llvm/DerivedTypes.h"
39 using namespace llvm;
40 
41 static bool CC_PPC_SVR4_Custom_Dummy(unsigned &ValNo, MVT &ValVT, MVT &LocVT,
42                                      CCValAssign::LocInfo &LocInfo,
43                                      ISD::ArgFlagsTy &ArgFlags,
44                                      CCState &State);
45 static bool CC_PPC_SVR4_Custom_AlignArgRegs(unsigned &ValNo, MVT &ValVT,
46                                             MVT &LocVT,
47                                             CCValAssign::LocInfo &LocInfo,
48                                             ISD::ArgFlagsTy &ArgFlags,
49                                             CCState &State);
50 static bool CC_PPC_SVR4_Custom_AlignFPArgRegs(unsigned &ValNo, MVT &ValVT,
51                                               MVT &LocVT,
52                                               CCValAssign::LocInfo &LocInfo,
53                                               ISD::ArgFlagsTy &ArgFlags,
54                                               CCState &State);
55 
56 static cl::opt<bool> EnablePPCPreinc("enable-ppc-preinc",
57 cl::desc("enable preincrement load/store generation on PPC (experimental)"),
58                                      cl::Hidden);
59 
CreateTLOF(const PPCTargetMachine & TM)60 static TargetLoweringObjectFile *CreateTLOF(const PPCTargetMachine &TM) {
61   if (TM.getSubtargetImpl()->isDarwin())
62     return new TargetLoweringObjectFileMachO();
63 
64   return new TargetLoweringObjectFileELF();
65 }
66 
PPCTargetLowering(PPCTargetMachine & TM)67 PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
68   : TargetLowering(TM, CreateTLOF(TM)), PPCSubTarget(*TM.getSubtargetImpl()) {
69 
70   setPow2DivIsCheap();
71 
72   // Use _setjmp/_longjmp instead of setjmp/longjmp.
73   setUseUnderscoreSetJmp(true);
74   setUseUnderscoreLongJmp(true);
75 
76   // On PPC32/64, arguments smaller than 4/8 bytes are extended, so all
77   // arguments are at least 4/8 bytes aligned.
78   setMinStackArgumentAlignment(TM.getSubtarget<PPCSubtarget>().isPPC64() ? 8:4);
79 
80   // Set up the register classes.
81   addRegisterClass(MVT::i32, PPC::GPRCRegisterClass);
82   addRegisterClass(MVT::f32, PPC::F4RCRegisterClass);
83   addRegisterClass(MVT::f64, PPC::F8RCRegisterClass);
84 
85   // PowerPC has an i16 but no i8 (or i1) SEXTLOAD
86   setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
87   setLoadExtAction(ISD::SEXTLOAD, MVT::i8, Expand);
88 
89   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
90 
91   // PowerPC has pre-inc load and store's.
92   setIndexedLoadAction(ISD::PRE_INC, MVT::i1, Legal);
93   setIndexedLoadAction(ISD::PRE_INC, MVT::i8, Legal);
94   setIndexedLoadAction(ISD::PRE_INC, MVT::i16, Legal);
95   setIndexedLoadAction(ISD::PRE_INC, MVT::i32, Legal);
96   setIndexedLoadAction(ISD::PRE_INC, MVT::i64, Legal);
97   setIndexedStoreAction(ISD::PRE_INC, MVT::i1, Legal);
98   setIndexedStoreAction(ISD::PRE_INC, MVT::i8, Legal);
99   setIndexedStoreAction(ISD::PRE_INC, MVT::i16, Legal);
100   setIndexedStoreAction(ISD::PRE_INC, MVT::i32, Legal);
101   setIndexedStoreAction(ISD::PRE_INC, MVT::i64, Legal);
102 
103   // This is used in the ppcf128->int sequence.  Note it has different semantics
104   // from FP_ROUND:  that rounds to nearest, this rounds to zero.
105   setOperationAction(ISD::FP_ROUND_INREG, MVT::ppcf128, Custom);
106 
107   // PowerPC has no SREM/UREM instructions
108   setOperationAction(ISD::SREM, MVT::i32, Expand);
109   setOperationAction(ISD::UREM, MVT::i32, Expand);
110   setOperationAction(ISD::SREM, MVT::i64, Expand);
111   setOperationAction(ISD::UREM, MVT::i64, Expand);
112 
113   // Don't use SMUL_LOHI/UMUL_LOHI or SDIVREM/UDIVREM to lower SREM/UREM.
114   setOperationAction(ISD::UMUL_LOHI, MVT::i32, Expand);
115   setOperationAction(ISD::SMUL_LOHI, MVT::i32, Expand);
116   setOperationAction(ISD::UMUL_LOHI, MVT::i64, Expand);
117   setOperationAction(ISD::SMUL_LOHI, MVT::i64, Expand);
118   setOperationAction(ISD::UDIVREM, MVT::i32, Expand);
119   setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
120   setOperationAction(ISD::UDIVREM, MVT::i64, Expand);
121   setOperationAction(ISD::SDIVREM, MVT::i64, Expand);
122 
123   // We don't support sin/cos/sqrt/fmod/pow
124   setOperationAction(ISD::FSIN , MVT::f64, Expand);
125   setOperationAction(ISD::FCOS , MVT::f64, Expand);
126   setOperationAction(ISD::FREM , MVT::f64, Expand);
127   setOperationAction(ISD::FPOW , MVT::f64, Expand);
128   setOperationAction(ISD::FMA  , MVT::f64, Expand);
129   setOperationAction(ISD::FSIN , MVT::f32, Expand);
130   setOperationAction(ISD::FCOS , MVT::f32, Expand);
131   setOperationAction(ISD::FREM , MVT::f32, Expand);
132   setOperationAction(ISD::FPOW , MVT::f32, Expand);
133   setOperationAction(ISD::FMA  , MVT::f32, Expand);
134 
135   setOperationAction(ISD::FLT_ROUNDS_, MVT::i32, Custom);
136 
137   // If we're enabling GP optimizations, use hardware square root
138   if (!TM.getSubtarget<PPCSubtarget>().hasFSQRT()) {
139     setOperationAction(ISD::FSQRT, MVT::f64, Expand);
140     setOperationAction(ISD::FSQRT, MVT::f32, Expand);
141   }
142 
143   setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
144   setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
145 
146   // PowerPC does not have BSWAP, CTPOP or CTTZ
147   setOperationAction(ISD::BSWAP, MVT::i32  , Expand);
148   setOperationAction(ISD::CTPOP, MVT::i32  , Expand);
149   setOperationAction(ISD::CTTZ , MVT::i32  , Expand);
150   setOperationAction(ISD::BSWAP, MVT::i64  , Expand);
151   setOperationAction(ISD::CTPOP, MVT::i64  , Expand);
152   setOperationAction(ISD::CTTZ , MVT::i64  , Expand);
153 
154   // PowerPC does not have ROTR
155   setOperationAction(ISD::ROTR, MVT::i32   , Expand);
156   setOperationAction(ISD::ROTR, MVT::i64   , Expand);
157 
158   // PowerPC does not have Select
159   setOperationAction(ISD::SELECT, MVT::i32, Expand);
160   setOperationAction(ISD::SELECT, MVT::i64, Expand);
161   setOperationAction(ISD::SELECT, MVT::f32, Expand);
162   setOperationAction(ISD::SELECT, MVT::f64, Expand);
163 
164   // PowerPC wants to turn select_cc of FP into fsel when possible.
165   setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
166   setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
167 
168   // PowerPC wants to optimize integer setcc a bit
169   setOperationAction(ISD::SETCC, MVT::i32, Custom);
170 
171   // PowerPC does not have BRCOND which requires SetCC
172   setOperationAction(ISD::BRCOND, MVT::Other, Expand);
173 
174   setOperationAction(ISD::BR_JT,  MVT::Other, Expand);
175 
176   // PowerPC turns FP_TO_SINT into FCTIWZ and some load/stores.
177   setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
178 
179   // PowerPC does not have [U|S]INT_TO_FP
180   setOperationAction(ISD::SINT_TO_FP, MVT::i32, Expand);
181   setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
182 
183   setOperationAction(ISD::BITCAST, MVT::f32, Expand);
184   setOperationAction(ISD::BITCAST, MVT::i32, Expand);
185   setOperationAction(ISD::BITCAST, MVT::i64, Expand);
186   setOperationAction(ISD::BITCAST, MVT::f64, Expand);
187 
188   // We cannot sextinreg(i1).  Expand to shifts.
189   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
190 
191   setOperationAction(ISD::EXCEPTIONADDR, MVT::i64, Expand);
192   setOperationAction(ISD::EHSELECTION,   MVT::i64, Expand);
193   setOperationAction(ISD::EXCEPTIONADDR, MVT::i32, Expand);
194   setOperationAction(ISD::EHSELECTION,   MVT::i32, Expand);
195 
196 
197   // We want to legalize GlobalAddress and ConstantPool nodes into the
198   // appropriate instructions to materialize the address.
199   setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
200   setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom);
201   setOperationAction(ISD::BlockAddress,  MVT::i32, Custom);
202   setOperationAction(ISD::ConstantPool,  MVT::i32, Custom);
203   setOperationAction(ISD::JumpTable,     MVT::i32, Custom);
204   setOperationAction(ISD::GlobalAddress, MVT::i64, Custom);
205   setOperationAction(ISD::GlobalTLSAddress, MVT::i64, Custom);
206   setOperationAction(ISD::BlockAddress,  MVT::i64, Custom);
207   setOperationAction(ISD::ConstantPool,  MVT::i64, Custom);
208   setOperationAction(ISD::JumpTable,     MVT::i64, Custom);
209 
210   // TRAP is legal.
211   setOperationAction(ISD::TRAP, MVT::Other, Legal);
212 
213   // TRAMPOLINE is custom lowered.
214   setOperationAction(ISD::INIT_TRAMPOLINE, MVT::Other, Custom);
215   setOperationAction(ISD::ADJUST_TRAMPOLINE, MVT::Other, Custom);
216 
217   // VASTART needs to be custom lowered to use the VarArgsFrameIndex
218   setOperationAction(ISD::VASTART           , MVT::Other, Custom);
219 
220   // VAARG is custom lowered with the 32-bit SVR4 ABI.
221   if (TM.getSubtarget<PPCSubtarget>().isSVR4ABI()
222       && !TM.getSubtarget<PPCSubtarget>().isPPC64()) {
223     setOperationAction(ISD::VAARG, MVT::Other, Custom);
224     setOperationAction(ISD::VAARG, MVT::i64, Custom);
225   } else
226     setOperationAction(ISD::VAARG, MVT::Other, Expand);
227 
228   // Use the default implementation.
229   setOperationAction(ISD::VACOPY            , MVT::Other, Expand);
230   setOperationAction(ISD::VAEND             , MVT::Other, Expand);
231   setOperationAction(ISD::STACKSAVE         , MVT::Other, Expand);
232   setOperationAction(ISD::STACKRESTORE      , MVT::Other, Custom);
233   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32  , Custom);
234   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64  , Custom);
235 
236   // We want to custom lower some of our intrinsics.
237   setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
238 
239   // Comparisons that require checking two conditions.
240   setCondCodeAction(ISD::SETULT, MVT::f32, Expand);
241   setCondCodeAction(ISD::SETULT, MVT::f64, Expand);
242   setCondCodeAction(ISD::SETUGT, MVT::f32, Expand);
243   setCondCodeAction(ISD::SETUGT, MVT::f64, Expand);
244   setCondCodeAction(ISD::SETUEQ, MVT::f32, Expand);
245   setCondCodeAction(ISD::SETUEQ, MVT::f64, Expand);
246   setCondCodeAction(ISD::SETOGE, MVT::f32, Expand);
247   setCondCodeAction(ISD::SETOGE, MVT::f64, Expand);
248   setCondCodeAction(ISD::SETOLE, MVT::f32, Expand);
249   setCondCodeAction(ISD::SETOLE, MVT::f64, Expand);
250   setCondCodeAction(ISD::SETONE, MVT::f32, Expand);
251   setCondCodeAction(ISD::SETONE, MVT::f64, Expand);
252 
253   if (TM.getSubtarget<PPCSubtarget>().has64BitSupport()) {
254     // They also have instructions for converting between i64 and fp.
255     setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
256     setOperationAction(ISD::FP_TO_UINT, MVT::i64, Expand);
257     setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
258     setOperationAction(ISD::UINT_TO_FP, MVT::i64, Expand);
259     // This is just the low 32 bits of a (signed) fp->i64 conversion.
260     // We cannot do this with Promote because i64 is not a legal type.
261     setOperationAction(ISD::FP_TO_UINT, MVT::i32, Custom);
262 
263     // FIXME: disable this lowered code.  This generates 64-bit register values,
264     // and we don't model the fact that the top part is clobbered by calls.  We
265     // need to flag these together so that the value isn't live across a call.
266     //setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
267   } else {
268     // PowerPC does not have FP_TO_UINT on 32-bit implementations.
269     setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
270   }
271 
272   if (TM.getSubtarget<PPCSubtarget>().use64BitRegs()) {
273     // 64-bit PowerPC implementations can support i64 types directly
274     addRegisterClass(MVT::i64, PPC::G8RCRegisterClass);
275     // BUILD_PAIR can't be handled natively, and should be expanded to shl/or
276     setOperationAction(ISD::BUILD_PAIR, MVT::i64, Expand);
277     // 64-bit PowerPC wants to expand i128 shifts itself.
278     setOperationAction(ISD::SHL_PARTS, MVT::i64, Custom);
279     setOperationAction(ISD::SRA_PARTS, MVT::i64, Custom);
280     setOperationAction(ISD::SRL_PARTS, MVT::i64, Custom);
281   } else {
282     // 32-bit PowerPC wants to expand i64 shifts itself.
283     setOperationAction(ISD::SHL_PARTS, MVT::i32, Custom);
284     setOperationAction(ISD::SRA_PARTS, MVT::i32, Custom);
285     setOperationAction(ISD::SRL_PARTS, MVT::i32, Custom);
286   }
287 
288   if (TM.getSubtarget<PPCSubtarget>().hasAltivec()) {
289     // First set operation action for all vector types to expand. Then we
290     // will selectively turn on ones that can be effectively codegen'd.
291     for (unsigned i = (unsigned)MVT::FIRST_VECTOR_VALUETYPE;
292          i <= (unsigned)MVT::LAST_VECTOR_VALUETYPE; ++i) {
293       MVT::SimpleValueType VT = (MVT::SimpleValueType)i;
294 
295       // add/sub are legal for all supported vector VT's.
296       setOperationAction(ISD::ADD , VT, Legal);
297       setOperationAction(ISD::SUB , VT, Legal);
298 
299       // We promote all shuffles to v16i8.
300       setOperationAction(ISD::VECTOR_SHUFFLE, VT, Promote);
301       AddPromotedToType (ISD::VECTOR_SHUFFLE, VT, MVT::v16i8);
302 
303       // We promote all non-typed operations to v4i32.
304       setOperationAction(ISD::AND   , VT, Promote);
305       AddPromotedToType (ISD::AND   , VT, MVT::v4i32);
306       setOperationAction(ISD::OR    , VT, Promote);
307       AddPromotedToType (ISD::OR    , VT, MVT::v4i32);
308       setOperationAction(ISD::XOR   , VT, Promote);
309       AddPromotedToType (ISD::XOR   , VT, MVT::v4i32);
310       setOperationAction(ISD::LOAD  , VT, Promote);
311       AddPromotedToType (ISD::LOAD  , VT, MVT::v4i32);
312       setOperationAction(ISD::SELECT, VT, Promote);
313       AddPromotedToType (ISD::SELECT, VT, MVT::v4i32);
314       setOperationAction(ISD::STORE, VT, Promote);
315       AddPromotedToType (ISD::STORE, VT, MVT::v4i32);
316 
317       // No other operations are legal.
318       setOperationAction(ISD::MUL , VT, Expand);
319       setOperationAction(ISD::SDIV, VT, Expand);
320       setOperationAction(ISD::SREM, VT, Expand);
321       setOperationAction(ISD::UDIV, VT, Expand);
322       setOperationAction(ISD::UREM, VT, Expand);
323       setOperationAction(ISD::FDIV, VT, Expand);
324       setOperationAction(ISD::FNEG, VT, Expand);
325       setOperationAction(ISD::EXTRACT_VECTOR_ELT, VT, Expand);
326       setOperationAction(ISD::INSERT_VECTOR_ELT, VT, Expand);
327       setOperationAction(ISD::BUILD_VECTOR, VT, Expand);
328       setOperationAction(ISD::UMUL_LOHI, VT, Expand);
329       setOperationAction(ISD::SMUL_LOHI, VT, Expand);
330       setOperationAction(ISD::UDIVREM, VT, Expand);
331       setOperationAction(ISD::SDIVREM, VT, Expand);
332       setOperationAction(ISD::SCALAR_TO_VECTOR, VT, Expand);
333       setOperationAction(ISD::FPOW, VT, Expand);
334       setOperationAction(ISD::CTPOP, VT, Expand);
335       setOperationAction(ISD::CTLZ, VT, Expand);
336       setOperationAction(ISD::CTTZ, VT, Expand);
337     }
338 
339     // We can custom expand all VECTOR_SHUFFLEs to VPERM, others we can handle
340     // with merges, splats, etc.
341     setOperationAction(ISD::VECTOR_SHUFFLE, MVT::v16i8, Custom);
342 
343     setOperationAction(ISD::AND   , MVT::v4i32, Legal);
344     setOperationAction(ISD::OR    , MVT::v4i32, Legal);
345     setOperationAction(ISD::XOR   , MVT::v4i32, Legal);
346     setOperationAction(ISD::LOAD  , MVT::v4i32, Legal);
347     setOperationAction(ISD::SELECT, MVT::v4i32, Expand);
348     setOperationAction(ISD::STORE , MVT::v4i32, Legal);
349 
350     addRegisterClass(MVT::v4f32, PPC::VRRCRegisterClass);
351     addRegisterClass(MVT::v4i32, PPC::VRRCRegisterClass);
352     addRegisterClass(MVT::v8i16, PPC::VRRCRegisterClass);
353     addRegisterClass(MVT::v16i8, PPC::VRRCRegisterClass);
354 
355     setOperationAction(ISD::MUL, MVT::v4f32, Legal);
356     setOperationAction(ISD::MUL, MVT::v4i32, Custom);
357     setOperationAction(ISD::MUL, MVT::v8i16, Custom);
358     setOperationAction(ISD::MUL, MVT::v16i8, Custom);
359 
360     setOperationAction(ISD::SCALAR_TO_VECTOR, MVT::v4f32, Custom);
361     setOperationAction(ISD::SCALAR_TO_VECTOR, MVT::v4i32, Custom);
362 
363     setOperationAction(ISD::BUILD_VECTOR, MVT::v16i8, Custom);
364     setOperationAction(ISD::BUILD_VECTOR, MVT::v8i16, Custom);
365     setOperationAction(ISD::BUILD_VECTOR, MVT::v4i32, Custom);
366     setOperationAction(ISD::BUILD_VECTOR, MVT::v4f32, Custom);
367   }
368 
369   setOperationAction(ISD::ATOMIC_LOAD,  MVT::i32, Expand);
370   setOperationAction(ISD::ATOMIC_STORE, MVT::i32, Expand);
371 
372   setBooleanContents(ZeroOrOneBooleanContent);
373   setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
374 
375   if (TM.getSubtarget<PPCSubtarget>().isPPC64()) {
376     setStackPointerRegisterToSaveRestore(PPC::X1);
377     setExceptionPointerRegister(PPC::X3);
378     setExceptionSelectorRegister(PPC::X4);
379   } else {
380     setStackPointerRegisterToSaveRestore(PPC::R1);
381     setExceptionPointerRegister(PPC::R3);
382     setExceptionSelectorRegister(PPC::R4);
383   }
384 
385   // We have target-specific dag combine patterns for the following nodes:
386   setTargetDAGCombine(ISD::SINT_TO_FP);
387   setTargetDAGCombine(ISD::STORE);
388   setTargetDAGCombine(ISD::BR_CC);
389   setTargetDAGCombine(ISD::BSWAP);
390 
391   // Darwin long double math library functions have $LDBL128 appended.
392   if (TM.getSubtarget<PPCSubtarget>().isDarwin()) {
393     setLibcallName(RTLIB::COS_PPCF128, "cosl$LDBL128");
394     setLibcallName(RTLIB::POW_PPCF128, "powl$LDBL128");
395     setLibcallName(RTLIB::REM_PPCF128, "fmodl$LDBL128");
396     setLibcallName(RTLIB::SIN_PPCF128, "sinl$LDBL128");
397     setLibcallName(RTLIB::SQRT_PPCF128, "sqrtl$LDBL128");
398     setLibcallName(RTLIB::LOG_PPCF128, "logl$LDBL128");
399     setLibcallName(RTLIB::LOG2_PPCF128, "log2l$LDBL128");
400     setLibcallName(RTLIB::LOG10_PPCF128, "log10l$LDBL128");
401     setLibcallName(RTLIB::EXP_PPCF128, "expl$LDBL128");
402     setLibcallName(RTLIB::EXP2_PPCF128, "exp2l$LDBL128");
403   }
404 
405   setMinFunctionAlignment(2);
406   if (PPCSubTarget.isDarwin())
407     setPrefFunctionAlignment(4);
408 
409   setInsertFencesForAtomic(true);
410 
411   computeRegisterProperties();
412 }
413 
414 /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
415 /// function arguments in the caller parameter area.
getByValTypeAlignment(Type * Ty) const416 unsigned PPCTargetLowering::getByValTypeAlignment(Type *Ty) const {
417   const TargetMachine &TM = getTargetMachine();
418   // Darwin passes everything on 4 byte boundary.
419   if (TM.getSubtarget<PPCSubtarget>().isDarwin())
420     return 4;
421   // FIXME SVR4 TBD
422   return 4;
423 }
424 
getTargetNodeName(unsigned Opcode) const425 const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
426   switch (Opcode) {
427   default: return 0;
428   case PPCISD::FSEL:            return "PPCISD::FSEL";
429   case PPCISD::FCFID:           return "PPCISD::FCFID";
430   case PPCISD::FCTIDZ:          return "PPCISD::FCTIDZ";
431   case PPCISD::FCTIWZ:          return "PPCISD::FCTIWZ";
432   case PPCISD::STFIWX:          return "PPCISD::STFIWX";
433   case PPCISD::VMADDFP:         return "PPCISD::VMADDFP";
434   case PPCISD::VNMSUBFP:        return "PPCISD::VNMSUBFP";
435   case PPCISD::VPERM:           return "PPCISD::VPERM";
436   case PPCISD::Hi:              return "PPCISD::Hi";
437   case PPCISD::Lo:              return "PPCISD::Lo";
438   case PPCISD::TOC_ENTRY:       return "PPCISD::TOC_ENTRY";
439   case PPCISD::TOC_RESTORE:     return "PPCISD::TOC_RESTORE";
440   case PPCISD::LOAD:            return "PPCISD::LOAD";
441   case PPCISD::LOAD_TOC:        return "PPCISD::LOAD_TOC";
442   case PPCISD::DYNALLOC:        return "PPCISD::DYNALLOC";
443   case PPCISD::GlobalBaseReg:   return "PPCISD::GlobalBaseReg";
444   case PPCISD::SRL:             return "PPCISD::SRL";
445   case PPCISD::SRA:             return "PPCISD::SRA";
446   case PPCISD::SHL:             return "PPCISD::SHL";
447   case PPCISD::EXTSW_32:        return "PPCISD::EXTSW_32";
448   case PPCISD::STD_32:          return "PPCISD::STD_32";
449   case PPCISD::CALL_SVR4:       return "PPCISD::CALL_SVR4";
450   case PPCISD::CALL_Darwin:     return "PPCISD::CALL_Darwin";
451   case PPCISD::NOP:             return "PPCISD::NOP";
452   case PPCISD::MTCTR:           return "PPCISD::MTCTR";
453   case PPCISD::BCTRL_Darwin:    return "PPCISD::BCTRL_Darwin";
454   case PPCISD::BCTRL_SVR4:      return "PPCISD::BCTRL_SVR4";
455   case PPCISD::RET_FLAG:        return "PPCISD::RET_FLAG";
456   case PPCISD::MFCR:            return "PPCISD::MFCR";
457   case PPCISD::VCMP:            return "PPCISD::VCMP";
458   case PPCISD::VCMPo:           return "PPCISD::VCMPo";
459   case PPCISD::LBRX:            return "PPCISD::LBRX";
460   case PPCISD::STBRX:           return "PPCISD::STBRX";
461   case PPCISD::LARX:            return "PPCISD::LARX";
462   case PPCISD::STCX:            return "PPCISD::STCX";
463   case PPCISD::COND_BRANCH:     return "PPCISD::COND_BRANCH";
464   case PPCISD::MFFS:            return "PPCISD::MFFS";
465   case PPCISD::MTFSB0:          return "PPCISD::MTFSB0";
466   case PPCISD::MTFSB1:          return "PPCISD::MTFSB1";
467   case PPCISD::FADDRTZ:         return "PPCISD::FADDRTZ";
468   case PPCISD::MTFSF:           return "PPCISD::MTFSF";
469   case PPCISD::TC_RETURN:       return "PPCISD::TC_RETURN";
470   }
471 }
472 
getSetCCResultType(EVT VT) const473 EVT PPCTargetLowering::getSetCCResultType(EVT VT) const {
474   return MVT::i32;
475 }
476 
477 //===----------------------------------------------------------------------===//
478 // Node matching predicates, for use by the tblgen matching code.
479 //===----------------------------------------------------------------------===//
480 
481 /// isFloatingPointZero - Return true if this is 0.0 or -0.0.
isFloatingPointZero(SDValue Op)482 static bool isFloatingPointZero(SDValue Op) {
483   if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Op))
484     return CFP->getValueAPF().isZero();
485   else if (ISD::isEXTLoad(Op.getNode()) || ISD::isNON_EXTLoad(Op.getNode())) {
486     // Maybe this has already been legalized into the constant pool?
487     if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(Op.getOperand(1)))
488       if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CP->getConstVal()))
489         return CFP->getValueAPF().isZero();
490   }
491   return false;
492 }
493 
494 /// isConstantOrUndef - Op is either an undef node or a ConstantSDNode.  Return
495 /// true if Op is undef or if it matches the specified value.
isConstantOrUndef(int Op,int Val)496 static bool isConstantOrUndef(int Op, int Val) {
497   return Op < 0 || Op == Val;
498 }
499 
500 /// isVPKUHUMShuffleMask - Return true if this is the shuffle mask for a
501 /// VPKUHUM instruction.
isVPKUHUMShuffleMask(ShuffleVectorSDNode * N,bool isUnary)502 bool PPC::isVPKUHUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary) {
503   if (!isUnary) {
504     for (unsigned i = 0; i != 16; ++i)
505       if (!isConstantOrUndef(N->getMaskElt(i),  i*2+1))
506         return false;
507   } else {
508     for (unsigned i = 0; i != 8; ++i)
509       if (!isConstantOrUndef(N->getMaskElt(i),    i*2+1) ||
510           !isConstantOrUndef(N->getMaskElt(i+8),  i*2+1))
511         return false;
512   }
513   return true;
514 }
515 
516 /// isVPKUWUMShuffleMask - Return true if this is the shuffle mask for a
517 /// VPKUWUM instruction.
isVPKUWUMShuffleMask(ShuffleVectorSDNode * N,bool isUnary)518 bool PPC::isVPKUWUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary) {
519   if (!isUnary) {
520     for (unsigned i = 0; i != 16; i += 2)
521       if (!isConstantOrUndef(N->getMaskElt(i  ),  i*2+2) ||
522           !isConstantOrUndef(N->getMaskElt(i+1),  i*2+3))
523         return false;
524   } else {
525     for (unsigned i = 0; i != 8; i += 2)
526       if (!isConstantOrUndef(N->getMaskElt(i  ),  i*2+2) ||
527           !isConstantOrUndef(N->getMaskElt(i+1),  i*2+3) ||
528           !isConstantOrUndef(N->getMaskElt(i+8),  i*2+2) ||
529           !isConstantOrUndef(N->getMaskElt(i+9),  i*2+3))
530         return false;
531   }
532   return true;
533 }
534 
535 /// isVMerge - Common function, used to match vmrg* shuffles.
536 ///
isVMerge(ShuffleVectorSDNode * N,unsigned UnitSize,unsigned LHSStart,unsigned RHSStart)537 static bool isVMerge(ShuffleVectorSDNode *N, unsigned UnitSize,
538                      unsigned LHSStart, unsigned RHSStart) {
539   assert(N->getValueType(0) == MVT::v16i8 &&
540          "PPC only supports shuffles by bytes!");
541   assert((UnitSize == 1 || UnitSize == 2 || UnitSize == 4) &&
542          "Unsupported merge size!");
543 
544   for (unsigned i = 0; i != 8/UnitSize; ++i)     // Step over units
545     for (unsigned j = 0; j != UnitSize; ++j) {   // Step over bytes within unit
546       if (!isConstantOrUndef(N->getMaskElt(i*UnitSize*2+j),
547                              LHSStart+j+i*UnitSize) ||
548           !isConstantOrUndef(N->getMaskElt(i*UnitSize*2+UnitSize+j),
549                              RHSStart+j+i*UnitSize))
550         return false;
551     }
552   return true;
553 }
554 
555 /// isVMRGLShuffleMask - Return true if this is a shuffle mask suitable for
556 /// a VRGL* instruction with the specified unit size (1,2 or 4 bytes).
isVMRGLShuffleMask(ShuffleVectorSDNode * N,unsigned UnitSize,bool isUnary)557 bool PPC::isVMRGLShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
558                              bool isUnary) {
559   if (!isUnary)
560     return isVMerge(N, UnitSize, 8, 24);
561   return isVMerge(N, UnitSize, 8, 8);
562 }
563 
564 /// isVMRGHShuffleMask - Return true if this is a shuffle mask suitable for
565 /// a VRGH* instruction with the specified unit size (1,2 or 4 bytes).
isVMRGHShuffleMask(ShuffleVectorSDNode * N,unsigned UnitSize,bool isUnary)566 bool PPC::isVMRGHShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
567                              bool isUnary) {
568   if (!isUnary)
569     return isVMerge(N, UnitSize, 0, 16);
570   return isVMerge(N, UnitSize, 0, 0);
571 }
572 
573 
574 /// isVSLDOIShuffleMask - If this is a vsldoi shuffle mask, return the shift
575 /// amount, otherwise return -1.
isVSLDOIShuffleMask(SDNode * N,bool isUnary)576 int PPC::isVSLDOIShuffleMask(SDNode *N, bool isUnary) {
577   assert(N->getValueType(0) == MVT::v16i8 &&
578          "PPC only supports shuffles by bytes!");
579 
580   ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(N);
581 
582   // Find the first non-undef value in the shuffle mask.
583   unsigned i;
584   for (i = 0; i != 16 && SVOp->getMaskElt(i) < 0; ++i)
585     /*search*/;
586 
587   if (i == 16) return -1;  // all undef.
588 
589   // Otherwise, check to see if the rest of the elements are consecutively
590   // numbered from this value.
591   unsigned ShiftAmt = SVOp->getMaskElt(i);
592   if (ShiftAmt < i) return -1;
593   ShiftAmt -= i;
594 
595   if (!isUnary) {
596     // Check the rest of the elements to see if they are consecutive.
597     for (++i; i != 16; ++i)
598       if (!isConstantOrUndef(SVOp->getMaskElt(i), ShiftAmt+i))
599         return -1;
600   } else {
601     // Check the rest of the elements to see if they are consecutive.
602     for (++i; i != 16; ++i)
603       if (!isConstantOrUndef(SVOp->getMaskElt(i), (ShiftAmt+i) & 15))
604         return -1;
605   }
606   return ShiftAmt;
607 }
608 
609 /// isSplatShuffleMask - Return true if the specified VECTOR_SHUFFLE operand
610 /// specifies a splat of a single element that is suitable for input to
611 /// VSPLTB/VSPLTH/VSPLTW.
isSplatShuffleMask(ShuffleVectorSDNode * N,unsigned EltSize)612 bool PPC::isSplatShuffleMask(ShuffleVectorSDNode *N, unsigned EltSize) {
613   assert(N->getValueType(0) == MVT::v16i8 &&
614          (EltSize == 1 || EltSize == 2 || EltSize == 4));
615 
616   // This is a splat operation if each element of the permute is the same, and
617   // if the value doesn't reference the second vector.
618   unsigned ElementBase = N->getMaskElt(0);
619 
620   // FIXME: Handle UNDEF elements too!
621   if (ElementBase >= 16)
622     return false;
623 
624   // Check that the indices are consecutive, in the case of a multi-byte element
625   // splatted with a v16i8 mask.
626   for (unsigned i = 1; i != EltSize; ++i)
627     if (N->getMaskElt(i) < 0 || N->getMaskElt(i) != (int)(i+ElementBase))
628       return false;
629 
630   for (unsigned i = EltSize, e = 16; i != e; i += EltSize) {
631     if (N->getMaskElt(i) < 0) continue;
632     for (unsigned j = 0; j != EltSize; ++j)
633       if (N->getMaskElt(i+j) != N->getMaskElt(j))
634         return false;
635   }
636   return true;
637 }
638 
639 /// isAllNegativeZeroVector - Returns true if all elements of build_vector
640 /// are -0.0.
isAllNegativeZeroVector(SDNode * N)641 bool PPC::isAllNegativeZeroVector(SDNode *N) {
642   BuildVectorSDNode *BV = cast<BuildVectorSDNode>(N);
643 
644   APInt APVal, APUndef;
645   unsigned BitSize;
646   bool HasAnyUndefs;
647 
648   if (BV->isConstantSplat(APVal, APUndef, BitSize, HasAnyUndefs, 32, true))
649     if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0)))
650       return CFP->getValueAPF().isNegZero();
651 
652   return false;
653 }
654 
655 /// getVSPLTImmediate - Return the appropriate VSPLT* immediate to splat the
656 /// specified isSplatShuffleMask VECTOR_SHUFFLE mask.
getVSPLTImmediate(SDNode * N,unsigned EltSize)657 unsigned PPC::getVSPLTImmediate(SDNode *N, unsigned EltSize) {
658   ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(N);
659   assert(isSplatShuffleMask(SVOp, EltSize));
660   return SVOp->getMaskElt(0) / EltSize;
661 }
662 
663 /// get_VSPLTI_elt - If this is a build_vector of constants which can be formed
664 /// by using a vspltis[bhw] instruction of the specified element size, return
665 /// the constant being splatted.  The ByteSize field indicates the number of
666 /// bytes of each element [124] -> [bhw].
get_VSPLTI_elt(SDNode * N,unsigned ByteSize,SelectionDAG & DAG)667 SDValue PPC::get_VSPLTI_elt(SDNode *N, unsigned ByteSize, SelectionDAG &DAG) {
668   SDValue OpVal(0, 0);
669 
670   // If ByteSize of the splat is bigger than the element size of the
671   // build_vector, then we have a case where we are checking for a splat where
672   // multiple elements of the buildvector are folded together into a single
673   // logical element of the splat (e.g. "vsplish 1" to splat {0,1}*8).
674   unsigned EltSize = 16/N->getNumOperands();
675   if (EltSize < ByteSize) {
676     unsigned Multiple = ByteSize/EltSize;   // Number of BV entries per spltval.
677     SDValue UniquedVals[4];
678     assert(Multiple > 1 && Multiple <= 4 && "How can this happen?");
679 
680     // See if all of the elements in the buildvector agree across.
681     for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
682       if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;
683       // If the element isn't a constant, bail fully out.
684       if (!isa<ConstantSDNode>(N->getOperand(i))) return SDValue();
685 
686 
687       if (UniquedVals[i&(Multiple-1)].getNode() == 0)
688         UniquedVals[i&(Multiple-1)] = N->getOperand(i);
689       else if (UniquedVals[i&(Multiple-1)] != N->getOperand(i))
690         return SDValue();  // no match.
691     }
692 
693     // Okay, if we reached this point, UniquedVals[0..Multiple-1] contains
694     // either constant or undef values that are identical for each chunk.  See
695     // if these chunks can form into a larger vspltis*.
696 
697     // Check to see if all of the leading entries are either 0 or -1.  If
698     // neither, then this won't fit into the immediate field.
699     bool LeadingZero = true;
700     bool LeadingOnes = true;
701     for (unsigned i = 0; i != Multiple-1; ++i) {
702       if (UniquedVals[i].getNode() == 0) continue;  // Must have been undefs.
703 
704       LeadingZero &= cast<ConstantSDNode>(UniquedVals[i])->isNullValue();
705       LeadingOnes &= cast<ConstantSDNode>(UniquedVals[i])->isAllOnesValue();
706     }
707     // Finally, check the least significant entry.
708     if (LeadingZero) {
709       if (UniquedVals[Multiple-1].getNode() == 0)
710         return DAG.getTargetConstant(0, MVT::i32);  // 0,0,0,undef
711       int Val = cast<ConstantSDNode>(UniquedVals[Multiple-1])->getZExtValue();
712       if (Val < 16)
713         return DAG.getTargetConstant(Val, MVT::i32);  // 0,0,0,4 -> vspltisw(4)
714     }
715     if (LeadingOnes) {
716       if (UniquedVals[Multiple-1].getNode() == 0)
717         return DAG.getTargetConstant(~0U, MVT::i32);  // -1,-1,-1,undef
718       int Val =cast<ConstantSDNode>(UniquedVals[Multiple-1])->getSExtValue();
719       if (Val >= -16)                            // -1,-1,-1,-2 -> vspltisw(-2)
720         return DAG.getTargetConstant(Val, MVT::i32);
721     }
722 
723     return SDValue();
724   }
725 
726   // Check to see if this buildvec has a single non-undef value in its elements.
727   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
728     if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;
729     if (OpVal.getNode() == 0)
730       OpVal = N->getOperand(i);
731     else if (OpVal != N->getOperand(i))
732       return SDValue();
733   }
734 
735   if (OpVal.getNode() == 0) return SDValue();  // All UNDEF: use implicit def.
736 
737   unsigned ValSizeInBytes = EltSize;
738   uint64_t Value = 0;
739   if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(OpVal)) {
740     Value = CN->getZExtValue();
741   } else if (ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(OpVal)) {
742     assert(CN->getValueType(0) == MVT::f32 && "Only one legal FP vector type!");
743     Value = FloatToBits(CN->getValueAPF().convertToFloat());
744   }
745 
746   // If the splat value is larger than the element value, then we can never do
747   // this splat.  The only case that we could fit the replicated bits into our
748   // immediate field for would be zero, and we prefer to use vxor for it.
749   if (ValSizeInBytes < ByteSize) return SDValue();
750 
751   // If the element value is larger than the splat value, cut it in half and
752   // check to see if the two halves are equal.  Continue doing this until we
753   // get to ByteSize.  This allows us to handle 0x01010101 as 0x01.
754   while (ValSizeInBytes > ByteSize) {
755     ValSizeInBytes >>= 1;
756 
757     // If the top half equals the bottom half, we're still ok.
758     if (((Value >> (ValSizeInBytes*8)) & ((1 << (8*ValSizeInBytes))-1)) !=
759          (Value                        & ((1 << (8*ValSizeInBytes))-1)))
760       return SDValue();
761   }
762 
763   // Properly sign extend the value.
764   int ShAmt = (4-ByteSize)*8;
765   int MaskVal = ((int)Value << ShAmt) >> ShAmt;
766 
767   // If this is zero, don't match, zero matches ISD::isBuildVectorAllZeros.
768   if (MaskVal == 0) return SDValue();
769 
770   // Finally, if this value fits in a 5 bit sext field, return it
771   if (((MaskVal << (32-5)) >> (32-5)) == MaskVal)
772     return DAG.getTargetConstant(MaskVal, MVT::i32);
773   return SDValue();
774 }
775 
776 //===----------------------------------------------------------------------===//
777 //  Addressing Mode Selection
778 //===----------------------------------------------------------------------===//
779 
780 /// isIntS16Immediate - This method tests to see if the node is either a 32-bit
781 /// or 64-bit immediate, and if the value can be accurately represented as a
782 /// sign extension from a 16-bit value.  If so, this returns true and the
783 /// immediate.
isIntS16Immediate(SDNode * N,short & Imm)784 static bool isIntS16Immediate(SDNode *N, short &Imm) {
785   if (N->getOpcode() != ISD::Constant)
786     return false;
787 
788   Imm = (short)cast<ConstantSDNode>(N)->getZExtValue();
789   if (N->getValueType(0) == MVT::i32)
790     return Imm == (int32_t)cast<ConstantSDNode>(N)->getZExtValue();
791   else
792     return Imm == (int64_t)cast<ConstantSDNode>(N)->getZExtValue();
793 }
isIntS16Immediate(SDValue Op,short & Imm)794 static bool isIntS16Immediate(SDValue Op, short &Imm) {
795   return isIntS16Immediate(Op.getNode(), Imm);
796 }
797 
798 
799 /// SelectAddressRegReg - Given the specified addressed, check to see if it
800 /// can be represented as an indexed [r+r] operation.  Returns false if it
801 /// can be more efficiently represented with [r+imm].
SelectAddressRegReg(SDValue N,SDValue & Base,SDValue & Index,SelectionDAG & DAG) const802 bool PPCTargetLowering::SelectAddressRegReg(SDValue N, SDValue &Base,
803                                             SDValue &Index,
804                                             SelectionDAG &DAG) const {
805   short imm = 0;
806   if (N.getOpcode() == ISD::ADD) {
807     if (isIntS16Immediate(N.getOperand(1), imm))
808       return false;    // r+i
809     if (N.getOperand(1).getOpcode() == PPCISD::Lo)
810       return false;    // r+i
811 
812     Base = N.getOperand(0);
813     Index = N.getOperand(1);
814     return true;
815   } else if (N.getOpcode() == ISD::OR) {
816     if (isIntS16Immediate(N.getOperand(1), imm))
817       return false;    // r+i can fold it if we can.
818 
819     // If this is an or of disjoint bitfields, we can codegen this as an add
820     // (for better address arithmetic) if the LHS and RHS of the OR are provably
821     // disjoint.
822     APInt LHSKnownZero, LHSKnownOne;
823     APInt RHSKnownZero, RHSKnownOne;
824     DAG.ComputeMaskedBits(N.getOperand(0),
825                           APInt::getAllOnesValue(N.getOperand(0)
826                             .getValueSizeInBits()),
827                           LHSKnownZero, LHSKnownOne);
828 
829     if (LHSKnownZero.getBoolValue()) {
830       DAG.ComputeMaskedBits(N.getOperand(1),
831                             APInt::getAllOnesValue(N.getOperand(1)
832                               .getValueSizeInBits()),
833                             RHSKnownZero, RHSKnownOne);
834       // If all of the bits are known zero on the LHS or RHS, the add won't
835       // carry.
836       if (~(LHSKnownZero | RHSKnownZero) == 0) {
837         Base = N.getOperand(0);
838         Index = N.getOperand(1);
839         return true;
840       }
841     }
842   }
843 
844   return false;
845 }
846 
847 /// Returns true if the address N can be represented by a base register plus
848 /// a signed 16-bit displacement [r+imm], and if it is not better
849 /// represented as reg+reg.
SelectAddressRegImm(SDValue N,SDValue & Disp,SDValue & Base,SelectionDAG & DAG) const850 bool PPCTargetLowering::SelectAddressRegImm(SDValue N, SDValue &Disp,
851                                             SDValue &Base,
852                                             SelectionDAG &DAG) const {
853   // FIXME dl should come from parent load or store, not from address
854   DebugLoc dl = N.getDebugLoc();
855   // If this can be more profitably realized as r+r, fail.
856   if (SelectAddressRegReg(N, Disp, Base, DAG))
857     return false;
858 
859   if (N.getOpcode() == ISD::ADD) {
860     short imm = 0;
861     if (isIntS16Immediate(N.getOperand(1), imm)) {
862       Disp = DAG.getTargetConstant((int)imm & 0xFFFF, MVT::i32);
863       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(N.getOperand(0))) {
864         Base = DAG.getTargetFrameIndex(FI->getIndex(), N.getValueType());
865       } else {
866         Base = N.getOperand(0);
867       }
868       return true; // [r+i]
869     } else if (N.getOperand(1).getOpcode() == PPCISD::Lo) {
870       // Match LOAD (ADD (X, Lo(G))).
871      assert(!cast<ConstantSDNode>(N.getOperand(1).getOperand(1))->getZExtValue()
872              && "Cannot handle constant offsets yet!");
873       Disp = N.getOperand(1).getOperand(0);  // The global address.
874       assert(Disp.getOpcode() == ISD::TargetGlobalAddress ||
875              Disp.getOpcode() == ISD::TargetConstantPool ||
876              Disp.getOpcode() == ISD::TargetJumpTable);
877       Base = N.getOperand(0);
878       return true;  // [&g+r]
879     }
880   } else if (N.getOpcode() == ISD::OR) {
881     short imm = 0;
882     if (isIntS16Immediate(N.getOperand(1), imm)) {
883       // If this is an or of disjoint bitfields, we can codegen this as an add
884       // (for better address arithmetic) if the LHS and RHS of the OR are
885       // provably disjoint.
886       APInt LHSKnownZero, LHSKnownOne;
887       DAG.ComputeMaskedBits(N.getOperand(0),
888                             APInt::getAllOnesValue(N.getOperand(0)
889                                                    .getValueSizeInBits()),
890                             LHSKnownZero, LHSKnownOne);
891 
892       if ((LHSKnownZero.getZExtValue()|~(uint64_t)imm) == ~0ULL) {
893         // If all of the bits are known zero on the LHS or RHS, the add won't
894         // carry.
895         Base = N.getOperand(0);
896         Disp = DAG.getTargetConstant((int)imm & 0xFFFF, MVT::i32);
897         return true;
898       }
899     }
900   } else if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N)) {
901     // Loading from a constant address.
902 
903     // If this address fits entirely in a 16-bit sext immediate field, codegen
904     // this as "d, 0"
905     short Imm;
906     if (isIntS16Immediate(CN, Imm)) {
907       Disp = DAG.getTargetConstant(Imm, CN->getValueType(0));
908       Base = DAG.getRegister(PPCSubTarget.isPPC64() ? PPC::X0 : PPC::R0,
909                              CN->getValueType(0));
910       return true;
911     }
912 
913     // Handle 32-bit sext immediates with LIS + addr mode.
914     if (CN->getValueType(0) == MVT::i32 ||
915         (int64_t)CN->getZExtValue() == (int)CN->getZExtValue()) {
916       int Addr = (int)CN->getZExtValue();
917 
918       // Otherwise, break this down into an LIS + disp.
919       Disp = DAG.getTargetConstant((short)Addr, MVT::i32);
920 
921       Base = DAG.getTargetConstant((Addr - (signed short)Addr) >> 16, MVT::i32);
922       unsigned Opc = CN->getValueType(0) == MVT::i32 ? PPC::LIS : PPC::LIS8;
923       Base = SDValue(DAG.getMachineNode(Opc, dl, CN->getValueType(0), Base), 0);
924       return true;
925     }
926   }
927 
928   Disp = DAG.getTargetConstant(0, getPointerTy());
929   if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(N))
930     Base = DAG.getTargetFrameIndex(FI->getIndex(), N.getValueType());
931   else
932     Base = N;
933   return true;      // [r+0]
934 }
935 
936 /// SelectAddressRegRegOnly - Given the specified addressed, force it to be
937 /// represented as an indexed [r+r] operation.
SelectAddressRegRegOnly(SDValue N,SDValue & Base,SDValue & Index,SelectionDAG & DAG) const938 bool PPCTargetLowering::SelectAddressRegRegOnly(SDValue N, SDValue &Base,
939                                                 SDValue &Index,
940                                                 SelectionDAG &DAG) const {
941   // Check to see if we can easily represent this as an [r+r] address.  This
942   // will fail if it thinks that the address is more profitably represented as
943   // reg+imm, e.g. where imm = 0.
944   if (SelectAddressRegReg(N, Base, Index, DAG))
945     return true;
946 
947   // If the operand is an addition, always emit this as [r+r], since this is
948   // better (for code size, and execution, as the memop does the add for free)
949   // than emitting an explicit add.
950   if (N.getOpcode() == ISD::ADD) {
951     Base = N.getOperand(0);
952     Index = N.getOperand(1);
953     return true;
954   }
955 
956   // Otherwise, do it the hard way, using R0 as the base register.
957   Base = DAG.getRegister(PPCSubTarget.isPPC64() ? PPC::X0 : PPC::R0,
958                          N.getValueType());
959   Index = N;
960   return true;
961 }
962 
963 /// SelectAddressRegImmShift - Returns true if the address N can be
964 /// represented by a base register plus a signed 14-bit displacement
965 /// [r+imm*4].  Suitable for use by STD and friends.
SelectAddressRegImmShift(SDValue N,SDValue & Disp,SDValue & Base,SelectionDAG & DAG) const966 bool PPCTargetLowering::SelectAddressRegImmShift(SDValue N, SDValue &Disp,
967                                                  SDValue &Base,
968                                                  SelectionDAG &DAG) const {
969   // FIXME dl should come from the parent load or store, not the address
970   DebugLoc dl = N.getDebugLoc();
971   // If this can be more profitably realized as r+r, fail.
972   if (SelectAddressRegReg(N, Disp, Base, DAG))
973     return false;
974 
975   if (N.getOpcode() == ISD::ADD) {
976     short imm = 0;
977     if (isIntS16Immediate(N.getOperand(1), imm) && (imm & 3) == 0) {
978       Disp =  DAG.getTargetConstant(((int)imm & 0xFFFF) >> 2, MVT::i32);
979       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(N.getOperand(0))) {
980         Base = DAG.getTargetFrameIndex(FI->getIndex(), N.getValueType());
981       } else {
982         Base = N.getOperand(0);
983       }
984       return true; // [r+i]
985     } else if (N.getOperand(1).getOpcode() == PPCISD::Lo) {
986       // Match LOAD (ADD (X, Lo(G))).
987      assert(!cast<ConstantSDNode>(N.getOperand(1).getOperand(1))->getZExtValue()
988              && "Cannot handle constant offsets yet!");
989       Disp = N.getOperand(1).getOperand(0);  // The global address.
990       assert(Disp.getOpcode() == ISD::TargetGlobalAddress ||
991              Disp.getOpcode() == ISD::TargetConstantPool ||
992              Disp.getOpcode() == ISD::TargetJumpTable);
993       Base = N.getOperand(0);
994       return true;  // [&g+r]
995     }
996   } else if (N.getOpcode() == ISD::OR) {
997     short imm = 0;
998     if (isIntS16Immediate(N.getOperand(1), imm) && (imm & 3) == 0) {
999       // If this is an or of disjoint bitfields, we can codegen this as an add
1000       // (for better address arithmetic) if the LHS and RHS of the OR are
1001       // provably disjoint.
1002       APInt LHSKnownZero, LHSKnownOne;
1003       DAG.ComputeMaskedBits(N.getOperand(0),
1004                             APInt::getAllOnesValue(N.getOperand(0)
1005                                                    .getValueSizeInBits()),
1006                             LHSKnownZero, LHSKnownOne);
1007       if ((LHSKnownZero.getZExtValue()|~(uint64_t)imm) == ~0ULL) {
1008         // If all of the bits are known zero on the LHS or RHS, the add won't
1009         // carry.
1010         Base = N.getOperand(0);
1011         Disp = DAG.getTargetConstant(((int)imm & 0xFFFF) >> 2, MVT::i32);
1012         return true;
1013       }
1014     }
1015   } else if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N)) {
1016     // Loading from a constant address.  Verify low two bits are clear.
1017     if ((CN->getZExtValue() & 3) == 0) {
1018       // If this address fits entirely in a 14-bit sext immediate field, codegen
1019       // this as "d, 0"
1020       short Imm;
1021       if (isIntS16Immediate(CN, Imm)) {
1022         Disp = DAG.getTargetConstant((unsigned short)Imm >> 2, getPointerTy());
1023         Base = DAG.getRegister(PPCSubTarget.isPPC64() ? PPC::X0 : PPC::R0,
1024                                CN->getValueType(0));
1025         return true;
1026       }
1027 
1028       // Fold the low-part of 32-bit absolute addresses into addr mode.
1029       if (CN->getValueType(0) == MVT::i32 ||
1030           (int64_t)CN->getZExtValue() == (int)CN->getZExtValue()) {
1031         int Addr = (int)CN->getZExtValue();
1032 
1033         // Otherwise, break this down into an LIS + disp.
1034         Disp = DAG.getTargetConstant((short)Addr >> 2, MVT::i32);
1035         Base = DAG.getTargetConstant((Addr-(signed short)Addr) >> 16, MVT::i32);
1036         unsigned Opc = CN->getValueType(0) == MVT::i32 ? PPC::LIS : PPC::LIS8;
1037         Base = SDValue(DAG.getMachineNode(Opc, dl, CN->getValueType(0), Base),0);
1038         return true;
1039       }
1040     }
1041   }
1042 
1043   Disp = DAG.getTargetConstant(0, getPointerTy());
1044   if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(N))
1045     Base = DAG.getTargetFrameIndex(FI->getIndex(), N.getValueType());
1046   else
1047     Base = N;
1048   return true;      // [r+0]
1049 }
1050 
1051 
1052 /// getPreIndexedAddressParts - returns true by value, base pointer and
1053 /// offset pointer and addressing mode by reference if the node's address
1054 /// can be legally represented as pre-indexed load / store address.
getPreIndexedAddressParts(SDNode * N,SDValue & Base,SDValue & Offset,ISD::MemIndexedMode & AM,SelectionDAG & DAG) const1055 bool PPCTargetLowering::getPreIndexedAddressParts(SDNode *N, SDValue &Base,
1056                                                   SDValue &Offset,
1057                                                   ISD::MemIndexedMode &AM,
1058                                                   SelectionDAG &DAG) const {
1059   // Disabled by default for now.
1060   if (!EnablePPCPreinc) return false;
1061 
1062   SDValue Ptr;
1063   EVT VT;
1064   if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
1065     Ptr = LD->getBasePtr();
1066     VT = LD->getMemoryVT();
1067 
1068   } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
1069     Ptr = ST->getBasePtr();
1070     VT  = ST->getMemoryVT();
1071   } else
1072     return false;
1073 
1074   // PowerPC doesn't have preinc load/store instructions for vectors.
1075   if (VT.isVector())
1076     return false;
1077 
1078   // TODO: Check reg+reg first.
1079 
1080   // LDU/STU use reg+imm*4, others use reg+imm.
1081   if (VT != MVT::i64) {
1082     // reg + imm
1083     if (!SelectAddressRegImm(Ptr, Offset, Base, DAG))
1084       return false;
1085   } else {
1086     // reg + imm * 4.
1087     if (!SelectAddressRegImmShift(Ptr, Offset, Base, DAG))
1088       return false;
1089   }
1090 
1091   if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
1092     // PPC64 doesn't have lwau, but it does have lwaux.  Reject preinc load of
1093     // sext i32 to i64 when addr mode is r+i.
1094     if (LD->getValueType(0) == MVT::i64 && LD->getMemoryVT() == MVT::i32 &&
1095         LD->getExtensionType() == ISD::SEXTLOAD &&
1096         isa<ConstantSDNode>(Offset))
1097       return false;
1098   }
1099 
1100   AM = ISD::PRE_INC;
1101   return true;
1102 }
1103 
1104 //===----------------------------------------------------------------------===//
1105 //  LowerOperation implementation
1106 //===----------------------------------------------------------------------===//
1107 
1108 /// GetLabelAccessInfo - Return true if we should reference labels using a
1109 /// PICBase, set the HiOpFlags and LoOpFlags to the target MO flags.
GetLabelAccessInfo(const TargetMachine & TM,unsigned & HiOpFlags,unsigned & LoOpFlags,const GlobalValue * GV=0)1110 static bool GetLabelAccessInfo(const TargetMachine &TM, unsigned &HiOpFlags,
1111                                unsigned &LoOpFlags, const GlobalValue *GV = 0) {
1112   HiOpFlags = PPCII::MO_HA16;
1113   LoOpFlags = PPCII::MO_LO16;
1114 
1115   // Don't use the pic base if not in PIC relocation model.  Or if we are on a
1116   // non-darwin platform.  We don't support PIC on other platforms yet.
1117   bool isPIC = TM.getRelocationModel() == Reloc::PIC_ &&
1118                TM.getSubtarget<PPCSubtarget>().isDarwin();
1119   if (isPIC) {
1120     HiOpFlags |= PPCII::MO_PIC_FLAG;
1121     LoOpFlags |= PPCII::MO_PIC_FLAG;
1122   }
1123 
1124   // If this is a reference to a global value that requires a non-lazy-ptr, make
1125   // sure that instruction lowering adds it.
1126   if (GV && TM.getSubtarget<PPCSubtarget>().hasLazyResolverStub(GV, TM)) {
1127     HiOpFlags |= PPCII::MO_NLP_FLAG;
1128     LoOpFlags |= PPCII::MO_NLP_FLAG;
1129 
1130     if (GV->hasHiddenVisibility()) {
1131       HiOpFlags |= PPCII::MO_NLP_HIDDEN_FLAG;
1132       LoOpFlags |= PPCII::MO_NLP_HIDDEN_FLAG;
1133     }
1134   }
1135 
1136   return isPIC;
1137 }
1138 
LowerLabelRef(SDValue HiPart,SDValue LoPart,bool isPIC,SelectionDAG & DAG)1139 static SDValue LowerLabelRef(SDValue HiPart, SDValue LoPart, bool isPIC,
1140                              SelectionDAG &DAG) {
1141   EVT PtrVT = HiPart.getValueType();
1142   SDValue Zero = DAG.getConstant(0, PtrVT);
1143   DebugLoc DL = HiPart.getDebugLoc();
1144 
1145   SDValue Hi = DAG.getNode(PPCISD::Hi, DL, PtrVT, HiPart, Zero);
1146   SDValue Lo = DAG.getNode(PPCISD::Lo, DL, PtrVT, LoPart, Zero);
1147 
1148   // With PIC, the first instruction is actually "GR+hi(&G)".
1149   if (isPIC)
1150     Hi = DAG.getNode(ISD::ADD, DL, PtrVT,
1151                      DAG.getNode(PPCISD::GlobalBaseReg, DL, PtrVT), Hi);
1152 
1153   // Generate non-pic code that has direct accesses to the constant pool.
1154   // The address of the global is just (hi(&g)+lo(&g)).
1155   return DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
1156 }
1157 
LowerConstantPool(SDValue Op,SelectionDAG & DAG) const1158 SDValue PPCTargetLowering::LowerConstantPool(SDValue Op,
1159                                              SelectionDAG &DAG) const {
1160   EVT PtrVT = Op.getValueType();
1161   ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
1162   const Constant *C = CP->getConstVal();
1163 
1164   unsigned MOHiFlag, MOLoFlag;
1165   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag);
1166   SDValue CPIHi =
1167     DAG.getTargetConstantPool(C, PtrVT, CP->getAlignment(), 0, MOHiFlag);
1168   SDValue CPILo =
1169     DAG.getTargetConstantPool(C, PtrVT, CP->getAlignment(), 0, MOLoFlag);
1170   return LowerLabelRef(CPIHi, CPILo, isPIC, DAG);
1171 }
1172 
LowerJumpTable(SDValue Op,SelectionDAG & DAG) const1173 SDValue PPCTargetLowering::LowerJumpTable(SDValue Op, SelectionDAG &DAG) const {
1174   EVT PtrVT = Op.getValueType();
1175   JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
1176 
1177   unsigned MOHiFlag, MOLoFlag;
1178   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag);
1179   SDValue JTIHi = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MOHiFlag);
1180   SDValue JTILo = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MOLoFlag);
1181   return LowerLabelRef(JTIHi, JTILo, isPIC, DAG);
1182 }
1183 
LowerBlockAddress(SDValue Op,SelectionDAG & DAG) const1184 SDValue PPCTargetLowering::LowerBlockAddress(SDValue Op,
1185                                              SelectionDAG &DAG) const {
1186   EVT PtrVT = Op.getValueType();
1187 
1188   const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
1189 
1190   unsigned MOHiFlag, MOLoFlag;
1191   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag);
1192   SDValue TgtBAHi = DAG.getBlockAddress(BA, PtrVT, /*isTarget=*/true, MOHiFlag);
1193   SDValue TgtBALo = DAG.getBlockAddress(BA, PtrVT, /*isTarget=*/true, MOLoFlag);
1194   return LowerLabelRef(TgtBAHi, TgtBALo, isPIC, DAG);
1195 }
1196 
LowerGlobalAddress(SDValue Op,SelectionDAG & DAG) const1197 SDValue PPCTargetLowering::LowerGlobalAddress(SDValue Op,
1198                                               SelectionDAG &DAG) const {
1199   EVT PtrVT = Op.getValueType();
1200   GlobalAddressSDNode *GSDN = cast<GlobalAddressSDNode>(Op);
1201   DebugLoc DL = GSDN->getDebugLoc();
1202   const GlobalValue *GV = GSDN->getGlobal();
1203 
1204   // 64-bit SVR4 ABI code is always position-independent.
1205   // The actual address of the GlobalValue is stored in the TOC.
1206   if (PPCSubTarget.isSVR4ABI() && PPCSubTarget.isPPC64()) {
1207     SDValue GA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, GSDN->getOffset());
1208     return DAG.getNode(PPCISD::TOC_ENTRY, DL, MVT::i64, GA,
1209                        DAG.getRegister(PPC::X2, MVT::i64));
1210   }
1211 
1212   unsigned MOHiFlag, MOLoFlag;
1213   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag, GV);
1214 
1215   SDValue GAHi =
1216     DAG.getTargetGlobalAddress(GV, DL, PtrVT, GSDN->getOffset(), MOHiFlag);
1217   SDValue GALo =
1218     DAG.getTargetGlobalAddress(GV, DL, PtrVT, GSDN->getOffset(), MOLoFlag);
1219 
1220   SDValue Ptr = LowerLabelRef(GAHi, GALo, isPIC, DAG);
1221 
1222   // If the global reference is actually to a non-lazy-pointer, we have to do an
1223   // extra load to get the address of the global.
1224   if (MOHiFlag & PPCII::MO_NLP_FLAG)
1225     Ptr = DAG.getLoad(PtrVT, DL, DAG.getEntryNode(), Ptr, MachinePointerInfo(),
1226                       false, false, 0);
1227   return Ptr;
1228 }
1229 
LowerSETCC(SDValue Op,SelectionDAG & DAG) const1230 SDValue PPCTargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1231   ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
1232   DebugLoc dl = Op.getDebugLoc();
1233 
1234   // If we're comparing for equality to zero, expose the fact that this is
1235   // implented as a ctlz/srl pair on ppc, so that the dag combiner can
1236   // fold the new nodes.
1237   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
1238     if (C->isNullValue() && CC == ISD::SETEQ) {
1239       EVT VT = Op.getOperand(0).getValueType();
1240       SDValue Zext = Op.getOperand(0);
1241       if (VT.bitsLT(MVT::i32)) {
1242         VT = MVT::i32;
1243         Zext = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, Op.getOperand(0));
1244       }
1245       unsigned Log2b = Log2_32(VT.getSizeInBits());
1246       SDValue Clz = DAG.getNode(ISD::CTLZ, dl, VT, Zext);
1247       SDValue Scc = DAG.getNode(ISD::SRL, dl, VT, Clz,
1248                                 DAG.getConstant(Log2b, MVT::i32));
1249       return DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Scc);
1250     }
1251     // Leave comparisons against 0 and -1 alone for now, since they're usually
1252     // optimized.  FIXME: revisit this when we can custom lower all setcc
1253     // optimizations.
1254     if (C->isAllOnesValue() || C->isNullValue())
1255       return SDValue();
1256   }
1257 
1258   // If we have an integer seteq/setne, turn it into a compare against zero
1259   // by xor'ing the rhs with the lhs, which is faster than setting a
1260   // condition register, reading it back out, and masking the correct bit.  The
1261   // normal approach here uses sub to do this instead of xor.  Using xor exposes
1262   // the result to other bit-twiddling opportunities.
1263   EVT LHSVT = Op.getOperand(0).getValueType();
1264   if (LHSVT.isInteger() && (CC == ISD::SETEQ || CC == ISD::SETNE)) {
1265     EVT VT = Op.getValueType();
1266     SDValue Sub = DAG.getNode(ISD::XOR, dl, LHSVT, Op.getOperand(0),
1267                                 Op.getOperand(1));
1268     return DAG.getSetCC(dl, VT, Sub, DAG.getConstant(0, LHSVT), CC);
1269   }
1270   return SDValue();
1271 }
1272 
LowerVAARG(SDValue Op,SelectionDAG & DAG,const PPCSubtarget & Subtarget) const1273 SDValue PPCTargetLowering::LowerVAARG(SDValue Op, SelectionDAG &DAG,
1274                                       const PPCSubtarget &Subtarget) const {
1275   SDNode *Node = Op.getNode();
1276   EVT VT = Node->getValueType(0);
1277   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1278   SDValue InChain = Node->getOperand(0);
1279   SDValue VAListPtr = Node->getOperand(1);
1280   const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
1281   DebugLoc dl = Node->getDebugLoc();
1282 
1283   assert(!Subtarget.isPPC64() && "LowerVAARG is PPC32 only");
1284 
1285   // gpr_index
1286   SDValue GprIndex = DAG.getExtLoad(ISD::ZEXTLOAD, dl, MVT::i32, InChain,
1287                                     VAListPtr, MachinePointerInfo(SV), MVT::i8,
1288                                     false, false, 0);
1289   InChain = GprIndex.getValue(1);
1290 
1291   if (VT == MVT::i64) {
1292     // Check if GprIndex is even
1293     SDValue GprAnd = DAG.getNode(ISD::AND, dl, MVT::i32, GprIndex,
1294                                  DAG.getConstant(1, MVT::i32));
1295     SDValue CC64 = DAG.getSetCC(dl, MVT::i32, GprAnd,
1296                                 DAG.getConstant(0, MVT::i32), ISD::SETNE);
1297     SDValue GprIndexPlusOne = DAG.getNode(ISD::ADD, dl, MVT::i32, GprIndex,
1298                                           DAG.getConstant(1, MVT::i32));
1299     // Align GprIndex to be even if it isn't
1300     GprIndex = DAG.getNode(ISD::SELECT, dl, MVT::i32, CC64, GprIndexPlusOne,
1301                            GprIndex);
1302   }
1303 
1304   // fpr index is 1 byte after gpr
1305   SDValue FprPtr = DAG.getNode(ISD::ADD, dl, PtrVT, VAListPtr,
1306                                DAG.getConstant(1, MVT::i32));
1307 
1308   // fpr
1309   SDValue FprIndex = DAG.getExtLoad(ISD::ZEXTLOAD, dl, MVT::i32, InChain,
1310                                     FprPtr, MachinePointerInfo(SV), MVT::i8,
1311                                     false, false, 0);
1312   InChain = FprIndex.getValue(1);
1313 
1314   SDValue RegSaveAreaPtr = DAG.getNode(ISD::ADD, dl, PtrVT, VAListPtr,
1315                                        DAG.getConstant(8, MVT::i32));
1316 
1317   SDValue OverflowAreaPtr = DAG.getNode(ISD::ADD, dl, PtrVT, VAListPtr,
1318                                         DAG.getConstant(4, MVT::i32));
1319 
1320   // areas
1321   SDValue OverflowArea = DAG.getLoad(MVT::i32, dl, InChain, OverflowAreaPtr,
1322                                      MachinePointerInfo(), false, false, 0);
1323   InChain = OverflowArea.getValue(1);
1324 
1325   SDValue RegSaveArea = DAG.getLoad(MVT::i32, dl, InChain, RegSaveAreaPtr,
1326                                     MachinePointerInfo(), false, false, 0);
1327   InChain = RegSaveArea.getValue(1);
1328 
1329   // select overflow_area if index > 8
1330   SDValue CC = DAG.getSetCC(dl, MVT::i32, VT.isInteger() ? GprIndex : FprIndex,
1331                             DAG.getConstant(8, MVT::i32), ISD::SETLT);
1332 
1333   // adjustment constant gpr_index * 4/8
1334   SDValue RegConstant = DAG.getNode(ISD::MUL, dl, MVT::i32,
1335                                     VT.isInteger() ? GprIndex : FprIndex,
1336                                     DAG.getConstant(VT.isInteger() ? 4 : 8,
1337                                                     MVT::i32));
1338 
1339   // OurReg = RegSaveArea + RegConstant
1340   SDValue OurReg = DAG.getNode(ISD::ADD, dl, PtrVT, RegSaveArea,
1341                                RegConstant);
1342 
1343   // Floating types are 32 bytes into RegSaveArea
1344   if (VT.isFloatingPoint())
1345     OurReg = DAG.getNode(ISD::ADD, dl, PtrVT, OurReg,
1346                          DAG.getConstant(32, MVT::i32));
1347 
1348   // increase {f,g}pr_index by 1 (or 2 if VT is i64)
1349   SDValue IndexPlus1 = DAG.getNode(ISD::ADD, dl, MVT::i32,
1350                                    VT.isInteger() ? GprIndex : FprIndex,
1351                                    DAG.getConstant(VT == MVT::i64 ? 2 : 1,
1352                                                    MVT::i32));
1353 
1354   InChain = DAG.getTruncStore(InChain, dl, IndexPlus1,
1355                               VT.isInteger() ? VAListPtr : FprPtr,
1356                               MachinePointerInfo(SV),
1357                               MVT::i8, false, false, 0);
1358 
1359   // determine if we should load from reg_save_area or overflow_area
1360   SDValue Result = DAG.getNode(ISD::SELECT, dl, PtrVT, CC, OurReg, OverflowArea);
1361 
1362   // increase overflow_area by 4/8 if gpr/fpr > 8
1363   SDValue OverflowAreaPlusN = DAG.getNode(ISD::ADD, dl, PtrVT, OverflowArea,
1364                                           DAG.getConstant(VT.isInteger() ? 4 : 8,
1365                                           MVT::i32));
1366 
1367   OverflowArea = DAG.getNode(ISD::SELECT, dl, MVT::i32, CC, OverflowArea,
1368                              OverflowAreaPlusN);
1369 
1370   InChain = DAG.getTruncStore(InChain, dl, OverflowArea,
1371                               OverflowAreaPtr,
1372                               MachinePointerInfo(),
1373                               MVT::i32, false, false, 0);
1374 
1375   return DAG.getLoad(VT, dl, InChain, Result, MachinePointerInfo(), false, false, 0);
1376 }
1377 
LowerADJUST_TRAMPOLINE(SDValue Op,SelectionDAG & DAG) const1378 SDValue PPCTargetLowering::LowerADJUST_TRAMPOLINE(SDValue Op,
1379                                                   SelectionDAG &DAG) const {
1380   return Op.getOperand(0);
1381 }
1382 
LowerINIT_TRAMPOLINE(SDValue Op,SelectionDAG & DAG) const1383 SDValue PPCTargetLowering::LowerINIT_TRAMPOLINE(SDValue Op,
1384                                                 SelectionDAG &DAG) const {
1385   SDValue Chain = Op.getOperand(0);
1386   SDValue Trmp = Op.getOperand(1); // trampoline
1387   SDValue FPtr = Op.getOperand(2); // nested function
1388   SDValue Nest = Op.getOperand(3); // 'nest' parameter value
1389   DebugLoc dl = Op.getDebugLoc();
1390 
1391   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1392   bool isPPC64 = (PtrVT == MVT::i64);
1393   Type *IntPtrTy =
1394     DAG.getTargetLoweringInfo().getTargetData()->getIntPtrType(
1395                                                              *DAG.getContext());
1396 
1397   TargetLowering::ArgListTy Args;
1398   TargetLowering::ArgListEntry Entry;
1399 
1400   Entry.Ty = IntPtrTy;
1401   Entry.Node = Trmp; Args.push_back(Entry);
1402 
1403   // TrampSize == (isPPC64 ? 48 : 40);
1404   Entry.Node = DAG.getConstant(isPPC64 ? 48 : 40,
1405                                isPPC64 ? MVT::i64 : MVT::i32);
1406   Args.push_back(Entry);
1407 
1408   Entry.Node = FPtr; Args.push_back(Entry);
1409   Entry.Node = Nest; Args.push_back(Entry);
1410 
1411   // Lower to a call to __trampoline_setup(Trmp, TrampSize, FPtr, ctx_reg)
1412   std::pair<SDValue, SDValue> CallResult =
1413     LowerCallTo(Chain, Type::getVoidTy(*DAG.getContext()),
1414                 false, false, false, false, 0, CallingConv::C, false,
1415                 /*isReturnValueUsed=*/true,
1416                 DAG.getExternalSymbol("__trampoline_setup", PtrVT),
1417                 Args, DAG, dl);
1418 
1419   return CallResult.second;
1420 }
1421 
LowerVASTART(SDValue Op,SelectionDAG & DAG,const PPCSubtarget & Subtarget) const1422 SDValue PPCTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG,
1423                                         const PPCSubtarget &Subtarget) const {
1424   MachineFunction &MF = DAG.getMachineFunction();
1425   PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
1426 
1427   DebugLoc dl = Op.getDebugLoc();
1428 
1429   if (Subtarget.isDarwinABI() || Subtarget.isPPC64()) {
1430     // vastart just stores the address of the VarArgsFrameIndex slot into the
1431     // memory location argument.
1432     EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1433     SDValue FR = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), PtrVT);
1434     const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1435     return DAG.getStore(Op.getOperand(0), dl, FR, Op.getOperand(1),
1436                         MachinePointerInfo(SV),
1437                         false, false, 0);
1438   }
1439 
1440   // For the 32-bit SVR4 ABI we follow the layout of the va_list struct.
1441   // We suppose the given va_list is already allocated.
1442   //
1443   // typedef struct {
1444   //  char gpr;     /* index into the array of 8 GPRs
1445   //                 * stored in the register save area
1446   //                 * gpr=0 corresponds to r3,
1447   //                 * gpr=1 to r4, etc.
1448   //                 */
1449   //  char fpr;     /* index into the array of 8 FPRs
1450   //                 * stored in the register save area
1451   //                 * fpr=0 corresponds to f1,
1452   //                 * fpr=1 to f2, etc.
1453   //                 */
1454   //  char *overflow_arg_area;
1455   //                /* location on stack that holds
1456   //                 * the next overflow argument
1457   //                 */
1458   //  char *reg_save_area;
1459   //               /* where r3:r10 and f1:f8 (if saved)
1460   //                * are stored
1461   //                */
1462   // } va_list[1];
1463 
1464 
1465   SDValue ArgGPR = DAG.getConstant(FuncInfo->getVarArgsNumGPR(), MVT::i32);
1466   SDValue ArgFPR = DAG.getConstant(FuncInfo->getVarArgsNumFPR(), MVT::i32);
1467 
1468 
1469   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1470 
1471   SDValue StackOffsetFI = DAG.getFrameIndex(FuncInfo->getVarArgsStackOffset(),
1472                                             PtrVT);
1473   SDValue FR = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
1474                                  PtrVT);
1475 
1476   uint64_t FrameOffset = PtrVT.getSizeInBits()/8;
1477   SDValue ConstFrameOffset = DAG.getConstant(FrameOffset, PtrVT);
1478 
1479   uint64_t StackOffset = PtrVT.getSizeInBits()/8 - 1;
1480   SDValue ConstStackOffset = DAG.getConstant(StackOffset, PtrVT);
1481 
1482   uint64_t FPROffset = 1;
1483   SDValue ConstFPROffset = DAG.getConstant(FPROffset, PtrVT);
1484 
1485   const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1486 
1487   // Store first byte : number of int regs
1488   SDValue firstStore = DAG.getTruncStore(Op.getOperand(0), dl, ArgGPR,
1489                                          Op.getOperand(1),
1490                                          MachinePointerInfo(SV),
1491                                          MVT::i8, false, false, 0);
1492   uint64_t nextOffset = FPROffset;
1493   SDValue nextPtr = DAG.getNode(ISD::ADD, dl, PtrVT, Op.getOperand(1),
1494                                   ConstFPROffset);
1495 
1496   // Store second byte : number of float regs
1497   SDValue secondStore =
1498     DAG.getTruncStore(firstStore, dl, ArgFPR, nextPtr,
1499                       MachinePointerInfo(SV, nextOffset), MVT::i8,
1500                       false, false, 0);
1501   nextOffset += StackOffset;
1502   nextPtr = DAG.getNode(ISD::ADD, dl, PtrVT, nextPtr, ConstStackOffset);
1503 
1504   // Store second word : arguments given on stack
1505   SDValue thirdStore =
1506     DAG.getStore(secondStore, dl, StackOffsetFI, nextPtr,
1507                  MachinePointerInfo(SV, nextOffset),
1508                  false, false, 0);
1509   nextOffset += FrameOffset;
1510   nextPtr = DAG.getNode(ISD::ADD, dl, PtrVT, nextPtr, ConstFrameOffset);
1511 
1512   // Store third word : arguments given in registers
1513   return DAG.getStore(thirdStore, dl, FR, nextPtr,
1514                       MachinePointerInfo(SV, nextOffset),
1515                       false, false, 0);
1516 
1517 }
1518 
1519 #include "PPCGenCallingConv.inc"
1520 
CC_PPC_SVR4_Custom_Dummy(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)1521 static bool CC_PPC_SVR4_Custom_Dummy(unsigned &ValNo, MVT &ValVT, MVT &LocVT,
1522                                      CCValAssign::LocInfo &LocInfo,
1523                                      ISD::ArgFlagsTy &ArgFlags,
1524                                      CCState &State) {
1525   return true;
1526 }
1527 
CC_PPC_SVR4_Custom_AlignArgRegs(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)1528 static bool CC_PPC_SVR4_Custom_AlignArgRegs(unsigned &ValNo, MVT &ValVT,
1529                                             MVT &LocVT,
1530                                             CCValAssign::LocInfo &LocInfo,
1531                                             ISD::ArgFlagsTy &ArgFlags,
1532                                             CCState &State) {
1533   static const unsigned ArgRegs[] = {
1534     PPC::R3, PPC::R4, PPC::R5, PPC::R6,
1535     PPC::R7, PPC::R8, PPC::R9, PPC::R10,
1536   };
1537   const unsigned NumArgRegs = array_lengthof(ArgRegs);
1538 
1539   unsigned RegNum = State.getFirstUnallocated(ArgRegs, NumArgRegs);
1540 
1541   // Skip one register if the first unallocated register has an even register
1542   // number and there are still argument registers available which have not been
1543   // allocated yet. RegNum is actually an index into ArgRegs, which means we
1544   // need to skip a register if RegNum is odd.
1545   if (RegNum != NumArgRegs && RegNum % 2 == 1) {
1546     State.AllocateReg(ArgRegs[RegNum]);
1547   }
1548 
1549   // Always return false here, as this function only makes sure that the first
1550   // unallocated register has an odd register number and does not actually
1551   // allocate a register for the current argument.
1552   return false;
1553 }
1554 
CC_PPC_SVR4_Custom_AlignFPArgRegs(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)1555 static bool CC_PPC_SVR4_Custom_AlignFPArgRegs(unsigned &ValNo, MVT &ValVT,
1556                                               MVT &LocVT,
1557                                               CCValAssign::LocInfo &LocInfo,
1558                                               ISD::ArgFlagsTy &ArgFlags,
1559                                               CCState &State) {
1560   static const unsigned ArgRegs[] = {
1561     PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7,
1562     PPC::F8
1563   };
1564 
1565   const unsigned NumArgRegs = array_lengthof(ArgRegs);
1566 
1567   unsigned RegNum = State.getFirstUnallocated(ArgRegs, NumArgRegs);
1568 
1569   // If there is only one Floating-point register left we need to put both f64
1570   // values of a split ppc_fp128 value on the stack.
1571   if (RegNum != NumArgRegs && ArgRegs[RegNum] == PPC::F8) {
1572     State.AllocateReg(ArgRegs[RegNum]);
1573   }
1574 
1575   // Always return false here, as this function only makes sure that the two f64
1576   // values a ppc_fp128 value is split into are both passed in registers or both
1577   // passed on the stack and does not actually allocate a register for the
1578   // current argument.
1579   return false;
1580 }
1581 
1582 /// GetFPR - Get the set of FP registers that should be allocated for arguments,
1583 /// on Darwin.
GetFPR()1584 static const unsigned *GetFPR() {
1585   static const unsigned FPR[] = {
1586     PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7,
1587     PPC::F8, PPC::F9, PPC::F10, PPC::F11, PPC::F12, PPC::F13
1588   };
1589 
1590   return FPR;
1591 }
1592 
1593 /// CalculateStackSlotSize - Calculates the size reserved for this argument on
1594 /// the stack.
CalculateStackSlotSize(EVT ArgVT,ISD::ArgFlagsTy Flags,unsigned PtrByteSize)1595 static unsigned CalculateStackSlotSize(EVT ArgVT, ISD::ArgFlagsTy Flags,
1596                                        unsigned PtrByteSize) {
1597   unsigned ArgSize = ArgVT.getSizeInBits()/8;
1598   if (Flags.isByVal())
1599     ArgSize = Flags.getByValSize();
1600   ArgSize = ((ArgSize + PtrByteSize - 1)/PtrByteSize) * PtrByteSize;
1601 
1602   return ArgSize;
1603 }
1604 
1605 SDValue
LowerFormalArguments(SDValue Chain,CallingConv::ID CallConv,bool isVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const1606 PPCTargetLowering::LowerFormalArguments(SDValue Chain,
1607                                         CallingConv::ID CallConv, bool isVarArg,
1608                                         const SmallVectorImpl<ISD::InputArg>
1609                                           &Ins,
1610                                         DebugLoc dl, SelectionDAG &DAG,
1611                                         SmallVectorImpl<SDValue> &InVals)
1612                                           const {
1613   if (PPCSubTarget.isSVR4ABI() && !PPCSubTarget.isPPC64()) {
1614     return LowerFormalArguments_SVR4(Chain, CallConv, isVarArg, Ins,
1615                                      dl, DAG, InVals);
1616   } else {
1617     return LowerFormalArguments_Darwin(Chain, CallConv, isVarArg, Ins,
1618                                        dl, DAG, InVals);
1619   }
1620 }
1621 
1622 SDValue
LowerFormalArguments_SVR4(SDValue Chain,CallingConv::ID CallConv,bool isVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const1623 PPCTargetLowering::LowerFormalArguments_SVR4(
1624                                       SDValue Chain,
1625                                       CallingConv::ID CallConv, bool isVarArg,
1626                                       const SmallVectorImpl<ISD::InputArg>
1627                                         &Ins,
1628                                       DebugLoc dl, SelectionDAG &DAG,
1629                                       SmallVectorImpl<SDValue> &InVals) const {
1630 
1631   // 32-bit SVR4 ABI Stack Frame Layout:
1632   //              +-----------------------------------+
1633   //        +-->  |            Back chain             |
1634   //        |     +-----------------------------------+
1635   //        |     | Floating-point register save area |
1636   //        |     +-----------------------------------+
1637   //        |     |    General register save area     |
1638   //        |     +-----------------------------------+
1639   //        |     |          CR save word             |
1640   //        |     +-----------------------------------+
1641   //        |     |         VRSAVE save word          |
1642   //        |     +-----------------------------------+
1643   //        |     |         Alignment padding         |
1644   //        |     +-----------------------------------+
1645   //        |     |     Vector register save area     |
1646   //        |     +-----------------------------------+
1647   //        |     |       Local variable space        |
1648   //        |     +-----------------------------------+
1649   //        |     |        Parameter list area        |
1650   //        |     +-----------------------------------+
1651   //        |     |           LR save word            |
1652   //        |     +-----------------------------------+
1653   // SP-->  +---  |            Back chain             |
1654   //              +-----------------------------------+
1655   //
1656   // Specifications:
1657   //   System V Application Binary Interface PowerPC Processor Supplement
1658   //   AltiVec Technology Programming Interface Manual
1659 
1660   MachineFunction &MF = DAG.getMachineFunction();
1661   MachineFrameInfo *MFI = MF.getFrameInfo();
1662   PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
1663 
1664   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1665   // Potential tail calls could cause overwriting of argument stack slots.
1666   bool isImmutable = !(GuaranteedTailCallOpt && (CallConv==CallingConv::Fast));
1667   unsigned PtrByteSize = 4;
1668 
1669   // Assign locations to all of the incoming arguments.
1670   SmallVector<CCValAssign, 16> ArgLocs;
1671   CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
1672 		 getTargetMachine(), ArgLocs, *DAG.getContext());
1673 
1674   // Reserve space for the linkage area on the stack.
1675   CCInfo.AllocateStack(PPCFrameLowering::getLinkageSize(false, false), PtrByteSize);
1676 
1677   CCInfo.AnalyzeFormalArguments(Ins, CC_PPC_SVR4);
1678 
1679   for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
1680     CCValAssign &VA = ArgLocs[i];
1681 
1682     // Arguments stored in registers.
1683     if (VA.isRegLoc()) {
1684       TargetRegisterClass *RC;
1685       EVT ValVT = VA.getValVT();
1686 
1687       switch (ValVT.getSimpleVT().SimpleTy) {
1688         default:
1689           llvm_unreachable("ValVT not supported by formal arguments Lowering");
1690         case MVT::i32:
1691           RC = PPC::GPRCRegisterClass;
1692           break;
1693         case MVT::f32:
1694           RC = PPC::F4RCRegisterClass;
1695           break;
1696         case MVT::f64:
1697           RC = PPC::F8RCRegisterClass;
1698           break;
1699         case MVT::v16i8:
1700         case MVT::v8i16:
1701         case MVT::v4i32:
1702         case MVT::v4f32:
1703           RC = PPC::VRRCRegisterClass;
1704           break;
1705       }
1706 
1707       // Transform the arguments stored in physical registers into virtual ones.
1708       unsigned Reg = MF.addLiveIn(VA.getLocReg(), RC);
1709       SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, ValVT);
1710 
1711       InVals.push_back(ArgValue);
1712     } else {
1713       // Argument stored in memory.
1714       assert(VA.isMemLoc());
1715 
1716       unsigned ArgSize = VA.getLocVT().getSizeInBits() / 8;
1717       int FI = MFI->CreateFixedObject(ArgSize, VA.getLocMemOffset(),
1718                                       isImmutable);
1719 
1720       // Create load nodes to retrieve arguments from the stack.
1721       SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
1722       InVals.push_back(DAG.getLoad(VA.getValVT(), dl, Chain, FIN,
1723                                    MachinePointerInfo(),
1724                                    false, false, 0));
1725     }
1726   }
1727 
1728   // Assign locations to all of the incoming aggregate by value arguments.
1729   // Aggregates passed by value are stored in the local variable space of the
1730   // caller's stack frame, right above the parameter list area.
1731   SmallVector<CCValAssign, 16> ByValArgLocs;
1732   CCState CCByValInfo(CallConv, isVarArg, DAG.getMachineFunction(),
1733 		      getTargetMachine(), ByValArgLocs, *DAG.getContext());
1734 
1735   // Reserve stack space for the allocations in CCInfo.
1736   CCByValInfo.AllocateStack(CCInfo.getNextStackOffset(), PtrByteSize);
1737 
1738   CCByValInfo.AnalyzeFormalArguments(Ins, CC_PPC_SVR4_ByVal);
1739 
1740   // Area that is at least reserved in the caller of this function.
1741   unsigned MinReservedArea = CCByValInfo.getNextStackOffset();
1742 
1743   // Set the size that is at least reserved in caller of this function.  Tail
1744   // call optimized function's reserved stack space needs to be aligned so that
1745   // taking the difference between two stack areas will result in an aligned
1746   // stack.
1747   PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
1748 
1749   MinReservedArea =
1750     std::max(MinReservedArea,
1751              PPCFrameLowering::getMinCallFrameSize(false, false));
1752 
1753   unsigned TargetAlign = DAG.getMachineFunction().getTarget().getFrameLowering()->
1754     getStackAlignment();
1755   unsigned AlignMask = TargetAlign-1;
1756   MinReservedArea = (MinReservedArea + AlignMask) & ~AlignMask;
1757 
1758   FI->setMinReservedArea(MinReservedArea);
1759 
1760   SmallVector<SDValue, 8> MemOps;
1761 
1762   // If the function takes variable number of arguments, make a frame index for
1763   // the start of the first vararg value... for expansion of llvm.va_start.
1764   if (isVarArg) {
1765     static const unsigned GPArgRegs[] = {
1766       PPC::R3, PPC::R4, PPC::R5, PPC::R6,
1767       PPC::R7, PPC::R8, PPC::R9, PPC::R10,
1768     };
1769     const unsigned NumGPArgRegs = array_lengthof(GPArgRegs);
1770 
1771     static const unsigned FPArgRegs[] = {
1772       PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7,
1773       PPC::F8
1774     };
1775     const unsigned NumFPArgRegs = array_lengthof(FPArgRegs);
1776 
1777     FuncInfo->setVarArgsNumGPR(CCInfo.getFirstUnallocated(GPArgRegs,
1778                                                           NumGPArgRegs));
1779     FuncInfo->setVarArgsNumFPR(CCInfo.getFirstUnallocated(FPArgRegs,
1780                                                           NumFPArgRegs));
1781 
1782     // Make room for NumGPArgRegs and NumFPArgRegs.
1783     int Depth = NumGPArgRegs * PtrVT.getSizeInBits()/8 +
1784                 NumFPArgRegs * EVT(MVT::f64).getSizeInBits()/8;
1785 
1786     FuncInfo->setVarArgsStackOffset(
1787       MFI->CreateFixedObject(PtrVT.getSizeInBits()/8,
1788                              CCInfo.getNextStackOffset(), true));
1789 
1790     FuncInfo->setVarArgsFrameIndex(MFI->CreateStackObject(Depth, 8, false));
1791     SDValue FIN = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), PtrVT);
1792 
1793     // The fixed integer arguments of a variadic function are stored to the
1794     // VarArgsFrameIndex on the stack so that they may be loaded by deferencing
1795     // the result of va_next.
1796     for (unsigned GPRIndex = 0; GPRIndex != NumGPArgRegs; ++GPRIndex) {
1797       // Get an existing live-in vreg, or add a new one.
1798       unsigned VReg = MF.getRegInfo().getLiveInVirtReg(GPArgRegs[GPRIndex]);
1799       if (!VReg)
1800         VReg = MF.addLiveIn(GPArgRegs[GPRIndex], &PPC::GPRCRegClass);
1801 
1802       SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, PtrVT);
1803       SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
1804                                    MachinePointerInfo(), false, false, 0);
1805       MemOps.push_back(Store);
1806       // Increment the address by four for the next argument to store
1807       SDValue PtrOff = DAG.getConstant(PtrVT.getSizeInBits()/8, PtrVT);
1808       FIN = DAG.getNode(ISD::ADD, dl, PtrOff.getValueType(), FIN, PtrOff);
1809     }
1810 
1811     // FIXME 32-bit SVR4: We only need to save FP argument registers if CR bit 6
1812     // is set.
1813     // The double arguments are stored to the VarArgsFrameIndex
1814     // on the stack.
1815     for (unsigned FPRIndex = 0; FPRIndex != NumFPArgRegs; ++FPRIndex) {
1816       // Get an existing live-in vreg, or add a new one.
1817       unsigned VReg = MF.getRegInfo().getLiveInVirtReg(FPArgRegs[FPRIndex]);
1818       if (!VReg)
1819         VReg = MF.addLiveIn(FPArgRegs[FPRIndex], &PPC::F8RCRegClass);
1820 
1821       SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::f64);
1822       SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
1823                                    MachinePointerInfo(), false, false, 0);
1824       MemOps.push_back(Store);
1825       // Increment the address by eight for the next argument to store
1826       SDValue PtrOff = DAG.getConstant(EVT(MVT::f64).getSizeInBits()/8,
1827                                          PtrVT);
1828       FIN = DAG.getNode(ISD::ADD, dl, PtrOff.getValueType(), FIN, PtrOff);
1829     }
1830   }
1831 
1832   if (!MemOps.empty())
1833     Chain = DAG.getNode(ISD::TokenFactor, dl,
1834                         MVT::Other, &MemOps[0], MemOps.size());
1835 
1836   return Chain;
1837 }
1838 
1839 SDValue
LowerFormalArguments_Darwin(SDValue Chain,CallingConv::ID CallConv,bool isVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const1840 PPCTargetLowering::LowerFormalArguments_Darwin(
1841                                       SDValue Chain,
1842                                       CallingConv::ID CallConv, bool isVarArg,
1843                                       const SmallVectorImpl<ISD::InputArg>
1844                                         &Ins,
1845                                       DebugLoc dl, SelectionDAG &DAG,
1846                                       SmallVectorImpl<SDValue> &InVals) const {
1847   // TODO: add description of PPC stack frame format, or at least some docs.
1848   //
1849   MachineFunction &MF = DAG.getMachineFunction();
1850   MachineFrameInfo *MFI = MF.getFrameInfo();
1851   PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
1852 
1853   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
1854   bool isPPC64 = PtrVT == MVT::i64;
1855   // Potential tail calls could cause overwriting of argument stack slots.
1856   bool isImmutable = !(GuaranteedTailCallOpt && (CallConv==CallingConv::Fast));
1857   unsigned PtrByteSize = isPPC64 ? 8 : 4;
1858 
1859   unsigned ArgOffset = PPCFrameLowering::getLinkageSize(isPPC64, true);
1860   // Area that is at least reserved in caller of this function.
1861   unsigned MinReservedArea = ArgOffset;
1862 
1863   static const unsigned GPR_32[] = {           // 32-bit registers.
1864     PPC::R3, PPC::R4, PPC::R5, PPC::R6,
1865     PPC::R7, PPC::R8, PPC::R9, PPC::R10,
1866   };
1867   static const unsigned GPR_64[] = {           // 64-bit registers.
1868     PPC::X3, PPC::X4, PPC::X5, PPC::X6,
1869     PPC::X7, PPC::X8, PPC::X9, PPC::X10,
1870   };
1871 
1872   static const unsigned *FPR = GetFPR();
1873 
1874   static const unsigned VR[] = {
1875     PPC::V2, PPC::V3, PPC::V4, PPC::V5, PPC::V6, PPC::V7, PPC::V8,
1876     PPC::V9, PPC::V10, PPC::V11, PPC::V12, PPC::V13
1877   };
1878 
1879   const unsigned Num_GPR_Regs = array_lengthof(GPR_32);
1880   const unsigned Num_FPR_Regs = 13;
1881   const unsigned Num_VR_Regs  = array_lengthof( VR);
1882 
1883   unsigned GPR_idx = 0, FPR_idx = 0, VR_idx = 0;
1884 
1885   const unsigned *GPR = isPPC64 ? GPR_64 : GPR_32;
1886 
1887   // In 32-bit non-varargs functions, the stack space for vectors is after the
1888   // stack space for non-vectors.  We do not use this space unless we have
1889   // too many vectors to fit in registers, something that only occurs in
1890   // constructed examples:), but we have to walk the arglist to figure
1891   // that out...for the pathological case, compute VecArgOffset as the
1892   // start of the vector parameter area.  Computing VecArgOffset is the
1893   // entire point of the following loop.
1894   unsigned VecArgOffset = ArgOffset;
1895   if (!isVarArg && !isPPC64) {
1896     for (unsigned ArgNo = 0, e = Ins.size(); ArgNo != e;
1897          ++ArgNo) {
1898       EVT ObjectVT = Ins[ArgNo].VT;
1899       unsigned ObjSize = ObjectVT.getSizeInBits()/8;
1900       ISD::ArgFlagsTy Flags = Ins[ArgNo].Flags;
1901 
1902       if (Flags.isByVal()) {
1903         // ObjSize is the true size, ArgSize rounded up to multiple of regs.
1904         ObjSize = Flags.getByValSize();
1905         unsigned ArgSize =
1906                 ((ObjSize + PtrByteSize - 1)/PtrByteSize) * PtrByteSize;
1907         VecArgOffset += ArgSize;
1908         continue;
1909       }
1910 
1911       switch(ObjectVT.getSimpleVT().SimpleTy) {
1912       default: llvm_unreachable("Unhandled argument type!");
1913       case MVT::i32:
1914       case MVT::f32:
1915         VecArgOffset += isPPC64 ? 8 : 4;
1916         break;
1917       case MVT::i64:  // PPC64
1918       case MVT::f64:
1919         VecArgOffset += 8;
1920         break;
1921       case MVT::v4f32:
1922       case MVT::v4i32:
1923       case MVT::v8i16:
1924       case MVT::v16i8:
1925         // Nothing to do, we're only looking at Nonvector args here.
1926         break;
1927       }
1928     }
1929   }
1930   // We've found where the vector parameter area in memory is.  Skip the
1931   // first 12 parameters; these don't use that memory.
1932   VecArgOffset = ((VecArgOffset+15)/16)*16;
1933   VecArgOffset += 12*16;
1934 
1935   // Add DAG nodes to load the arguments or copy them out of registers.  On
1936   // entry to a function on PPC, the arguments start after the linkage area,
1937   // although the first ones are often in registers.
1938 
1939   SmallVector<SDValue, 8> MemOps;
1940   unsigned nAltivecParamsAtEnd = 0;
1941   for (unsigned ArgNo = 0, e = Ins.size(); ArgNo != e; ++ArgNo) {
1942     SDValue ArgVal;
1943     bool needsLoad = false;
1944     EVT ObjectVT = Ins[ArgNo].VT;
1945     unsigned ObjSize = ObjectVT.getSizeInBits()/8;
1946     unsigned ArgSize = ObjSize;
1947     ISD::ArgFlagsTy Flags = Ins[ArgNo].Flags;
1948 
1949     unsigned CurArgOffset = ArgOffset;
1950 
1951     // Varargs or 64 bit Altivec parameters are padded to a 16 byte boundary.
1952     if (ObjectVT==MVT::v4f32 || ObjectVT==MVT::v4i32 ||
1953         ObjectVT==MVT::v8i16 || ObjectVT==MVT::v16i8) {
1954       if (isVarArg || isPPC64) {
1955         MinReservedArea = ((MinReservedArea+15)/16)*16;
1956         MinReservedArea += CalculateStackSlotSize(ObjectVT,
1957                                                   Flags,
1958                                                   PtrByteSize);
1959       } else  nAltivecParamsAtEnd++;
1960     } else
1961       // Calculate min reserved area.
1962       MinReservedArea += CalculateStackSlotSize(Ins[ArgNo].VT,
1963                                                 Flags,
1964                                                 PtrByteSize);
1965 
1966     // FIXME the codegen can be much improved in some cases.
1967     // We do not have to keep everything in memory.
1968     if (Flags.isByVal()) {
1969       // ObjSize is the true size, ArgSize rounded up to multiple of registers.
1970       ObjSize = Flags.getByValSize();
1971       ArgSize = ((ObjSize + PtrByteSize - 1)/PtrByteSize) * PtrByteSize;
1972       // Objects of size 1 and 2 are right justified, everything else is
1973       // left justified.  This means the memory address is adjusted forwards.
1974       if (ObjSize==1 || ObjSize==2) {
1975         CurArgOffset = CurArgOffset + (4 - ObjSize);
1976       }
1977       // The value of the object is its address.
1978       int FI = MFI->CreateFixedObject(ObjSize, CurArgOffset, true);
1979       SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
1980       InVals.push_back(FIN);
1981       if (ObjSize==1 || ObjSize==2) {
1982         if (GPR_idx != Num_GPR_Regs) {
1983           unsigned VReg;
1984           if (isPPC64)
1985             VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::G8RCRegClass);
1986           else
1987             VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::GPRCRegClass);
1988           SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, PtrVT);
1989           SDValue Store = DAG.getTruncStore(Val.getValue(1), dl, Val, FIN,
1990                                             MachinePointerInfo(),
1991                                             ObjSize==1 ? MVT::i8 : MVT::i16,
1992                                             false, false, 0);
1993           MemOps.push_back(Store);
1994           ++GPR_idx;
1995         }
1996 
1997         ArgOffset += PtrByteSize;
1998 
1999         continue;
2000       }
2001       for (unsigned j = 0; j < ArgSize; j += PtrByteSize) {
2002         // Store whatever pieces of the object are in registers
2003         // to memory.  ArgVal will be address of the beginning of
2004         // the object.
2005         if (GPR_idx != Num_GPR_Regs) {
2006           unsigned VReg;
2007           if (isPPC64)
2008             VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::G8RCRegClass);
2009           else
2010             VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::GPRCRegClass);
2011           int FI = MFI->CreateFixedObject(PtrByteSize, ArgOffset, true);
2012           SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
2013           SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, PtrVT);
2014           SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
2015                                        MachinePointerInfo(),
2016                                        false, false, 0);
2017           MemOps.push_back(Store);
2018           ++GPR_idx;
2019           ArgOffset += PtrByteSize;
2020         } else {
2021           ArgOffset += ArgSize - (ArgOffset-CurArgOffset);
2022           break;
2023         }
2024       }
2025       continue;
2026     }
2027 
2028     switch (ObjectVT.getSimpleVT().SimpleTy) {
2029     default: llvm_unreachable("Unhandled argument type!");
2030     case MVT::i32:
2031       if (!isPPC64) {
2032         if (GPR_idx != Num_GPR_Regs) {
2033           unsigned VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::GPRCRegClass);
2034           ArgVal = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
2035           ++GPR_idx;
2036         } else {
2037           needsLoad = true;
2038           ArgSize = PtrByteSize;
2039         }
2040         // All int arguments reserve stack space in the Darwin ABI.
2041         ArgOffset += PtrByteSize;
2042         break;
2043       }
2044       // FALLTHROUGH
2045     case MVT::i64:  // PPC64
2046       if (GPR_idx != Num_GPR_Regs) {
2047         unsigned VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::G8RCRegClass);
2048         ArgVal = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i64);
2049 
2050         if (ObjectVT == MVT::i32) {
2051           // PPC64 passes i8, i16, and i32 values in i64 registers. Promote
2052           // value to MVT::i64 and then truncate to the correct register size.
2053           if (Flags.isSExt())
2054             ArgVal = DAG.getNode(ISD::AssertSext, dl, MVT::i64, ArgVal,
2055                                  DAG.getValueType(ObjectVT));
2056           else if (Flags.isZExt())
2057             ArgVal = DAG.getNode(ISD::AssertZext, dl, MVT::i64, ArgVal,
2058                                  DAG.getValueType(ObjectVT));
2059 
2060           ArgVal = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, ArgVal);
2061         }
2062 
2063         ++GPR_idx;
2064       } else {
2065         needsLoad = true;
2066         ArgSize = PtrByteSize;
2067       }
2068       // All int arguments reserve stack space in the Darwin ABI.
2069       ArgOffset += 8;
2070       break;
2071 
2072     case MVT::f32:
2073     case MVT::f64:
2074       // Every 4 bytes of argument space consumes one of the GPRs available for
2075       // argument passing.
2076       if (GPR_idx != Num_GPR_Regs) {
2077         ++GPR_idx;
2078         if (ObjSize == 8 && GPR_idx != Num_GPR_Regs && !isPPC64)
2079           ++GPR_idx;
2080       }
2081       if (FPR_idx != Num_FPR_Regs) {
2082         unsigned VReg;
2083 
2084         if (ObjectVT == MVT::f32)
2085           VReg = MF.addLiveIn(FPR[FPR_idx], &PPC::F4RCRegClass);
2086         else
2087           VReg = MF.addLiveIn(FPR[FPR_idx], &PPC::F8RCRegClass);
2088 
2089         ArgVal = DAG.getCopyFromReg(Chain, dl, VReg, ObjectVT);
2090         ++FPR_idx;
2091       } else {
2092         needsLoad = true;
2093       }
2094 
2095       // All FP arguments reserve stack space in the Darwin ABI.
2096       ArgOffset += isPPC64 ? 8 : ObjSize;
2097       break;
2098     case MVT::v4f32:
2099     case MVT::v4i32:
2100     case MVT::v8i16:
2101     case MVT::v16i8:
2102       // Note that vector arguments in registers don't reserve stack space,
2103       // except in varargs functions.
2104       if (VR_idx != Num_VR_Regs) {
2105         unsigned VReg = MF.addLiveIn(VR[VR_idx], &PPC::VRRCRegClass);
2106         ArgVal = DAG.getCopyFromReg(Chain, dl, VReg, ObjectVT);
2107         if (isVarArg) {
2108           while ((ArgOffset % 16) != 0) {
2109             ArgOffset += PtrByteSize;
2110             if (GPR_idx != Num_GPR_Regs)
2111               GPR_idx++;
2112           }
2113           ArgOffset += 16;
2114           GPR_idx = std::min(GPR_idx+4, Num_GPR_Regs); // FIXME correct for ppc64?
2115         }
2116         ++VR_idx;
2117       } else {
2118         if (!isVarArg && !isPPC64) {
2119           // Vectors go after all the nonvectors.
2120           CurArgOffset = VecArgOffset;
2121           VecArgOffset += 16;
2122         } else {
2123           // Vectors are aligned.
2124           ArgOffset = ((ArgOffset+15)/16)*16;
2125           CurArgOffset = ArgOffset;
2126           ArgOffset += 16;
2127         }
2128         needsLoad = true;
2129       }
2130       break;
2131     }
2132 
2133     // We need to load the argument to a virtual register if we determined above
2134     // that we ran out of physical registers of the appropriate type.
2135     if (needsLoad) {
2136       int FI = MFI->CreateFixedObject(ObjSize,
2137                                       CurArgOffset + (ArgSize - ObjSize),
2138                                       isImmutable);
2139       SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
2140       ArgVal = DAG.getLoad(ObjectVT, dl, Chain, FIN, MachinePointerInfo(),
2141                            false, false, 0);
2142     }
2143 
2144     InVals.push_back(ArgVal);
2145   }
2146 
2147   // Set the size that is at least reserved in caller of this function.  Tail
2148   // call optimized function's reserved stack space needs to be aligned so that
2149   // taking the difference between two stack areas will result in an aligned
2150   // stack.
2151   PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
2152   // Add the Altivec parameters at the end, if needed.
2153   if (nAltivecParamsAtEnd) {
2154     MinReservedArea = ((MinReservedArea+15)/16)*16;
2155     MinReservedArea += 16*nAltivecParamsAtEnd;
2156   }
2157   MinReservedArea =
2158     std::max(MinReservedArea,
2159              PPCFrameLowering::getMinCallFrameSize(isPPC64, true));
2160   unsigned TargetAlign = DAG.getMachineFunction().getTarget().getFrameLowering()->
2161     getStackAlignment();
2162   unsigned AlignMask = TargetAlign-1;
2163   MinReservedArea = (MinReservedArea + AlignMask) & ~AlignMask;
2164   FI->setMinReservedArea(MinReservedArea);
2165 
2166   // If the function takes variable number of arguments, make a frame index for
2167   // the start of the first vararg value... for expansion of llvm.va_start.
2168   if (isVarArg) {
2169     int Depth = ArgOffset;
2170 
2171     FuncInfo->setVarArgsFrameIndex(
2172       MFI->CreateFixedObject(PtrVT.getSizeInBits()/8,
2173                              Depth, true));
2174     SDValue FIN = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), PtrVT);
2175 
2176     // If this function is vararg, store any remaining integer argument regs
2177     // to their spots on the stack so that they may be loaded by deferencing the
2178     // result of va_next.
2179     for (; GPR_idx != Num_GPR_Regs; ++GPR_idx) {
2180       unsigned VReg;
2181 
2182       if (isPPC64)
2183         VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::G8RCRegClass);
2184       else
2185         VReg = MF.addLiveIn(GPR[GPR_idx], &PPC::GPRCRegClass);
2186 
2187       SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, PtrVT);
2188       SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
2189                                    MachinePointerInfo(), false, false, 0);
2190       MemOps.push_back(Store);
2191       // Increment the address by four for the next argument to store
2192       SDValue PtrOff = DAG.getConstant(PtrVT.getSizeInBits()/8, PtrVT);
2193       FIN = DAG.getNode(ISD::ADD, dl, PtrOff.getValueType(), FIN, PtrOff);
2194     }
2195   }
2196 
2197   if (!MemOps.empty())
2198     Chain = DAG.getNode(ISD::TokenFactor, dl,
2199                         MVT::Other, &MemOps[0], MemOps.size());
2200 
2201   return Chain;
2202 }
2203 
2204 /// CalculateParameterAndLinkageAreaSize - Get the size of the paramter plus
2205 /// linkage area for the Darwin ABI.
2206 static unsigned
CalculateParameterAndLinkageAreaSize(SelectionDAG & DAG,bool isPPC64,bool isVarArg,unsigned CC,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,unsigned & nAltivecParamsAtEnd)2207 CalculateParameterAndLinkageAreaSize(SelectionDAG &DAG,
2208                                      bool isPPC64,
2209                                      bool isVarArg,
2210                                      unsigned CC,
2211                                      const SmallVectorImpl<ISD::OutputArg>
2212                                        &Outs,
2213                                      const SmallVectorImpl<SDValue> &OutVals,
2214                                      unsigned &nAltivecParamsAtEnd) {
2215   // Count how many bytes are to be pushed on the stack, including the linkage
2216   // area, and parameter passing area.  We start with 24/48 bytes, which is
2217   // prereserved space for [SP][CR][LR][3 x unused].
2218   unsigned NumBytes = PPCFrameLowering::getLinkageSize(isPPC64, true);
2219   unsigned NumOps = Outs.size();
2220   unsigned PtrByteSize = isPPC64 ? 8 : 4;
2221 
2222   // Add up all the space actually used.
2223   // In 32-bit non-varargs calls, Altivec parameters all go at the end; usually
2224   // they all go in registers, but we must reserve stack space for them for
2225   // possible use by the caller.  In varargs or 64-bit calls, parameters are
2226   // assigned stack space in order, with padding so Altivec parameters are
2227   // 16-byte aligned.
2228   nAltivecParamsAtEnd = 0;
2229   for (unsigned i = 0; i != NumOps; ++i) {
2230     ISD::ArgFlagsTy Flags = Outs[i].Flags;
2231     EVT ArgVT = Outs[i].VT;
2232     // Varargs Altivec parameters are padded to a 16 byte boundary.
2233     if (ArgVT==MVT::v4f32 || ArgVT==MVT::v4i32 ||
2234         ArgVT==MVT::v8i16 || ArgVT==MVT::v16i8) {
2235       if (!isVarArg && !isPPC64) {
2236         // Non-varargs Altivec parameters go after all the non-Altivec
2237         // parameters; handle those later so we know how much padding we need.
2238         nAltivecParamsAtEnd++;
2239         continue;
2240       }
2241       // Varargs and 64-bit Altivec parameters are padded to 16 byte boundary.
2242       NumBytes = ((NumBytes+15)/16)*16;
2243     }
2244     NumBytes += CalculateStackSlotSize(ArgVT, Flags, PtrByteSize);
2245   }
2246 
2247    // Allow for Altivec parameters at the end, if needed.
2248   if (nAltivecParamsAtEnd) {
2249     NumBytes = ((NumBytes+15)/16)*16;
2250     NumBytes += 16*nAltivecParamsAtEnd;
2251   }
2252 
2253   // The prolog code of the callee may store up to 8 GPR argument registers to
2254   // the stack, allowing va_start to index over them in memory if its varargs.
2255   // Because we cannot tell if this is needed on the caller side, we have to
2256   // conservatively assume that it is needed.  As such, make sure we have at
2257   // least enough stack space for the caller to store the 8 GPRs.
2258   NumBytes = std::max(NumBytes,
2259                       PPCFrameLowering::getMinCallFrameSize(isPPC64, true));
2260 
2261   // Tail call needs the stack to be aligned.
2262   if (CC==CallingConv::Fast && GuaranteedTailCallOpt) {
2263     unsigned TargetAlign = DAG.getMachineFunction().getTarget().getFrameLowering()->
2264       getStackAlignment();
2265     unsigned AlignMask = TargetAlign-1;
2266     NumBytes = (NumBytes + AlignMask) & ~AlignMask;
2267   }
2268 
2269   return NumBytes;
2270 }
2271 
2272 /// CalculateTailCallSPDiff - Get the amount the stack pointer has to be
2273 /// adjusted to accommodate the arguments for the tailcall.
CalculateTailCallSPDiff(SelectionDAG & DAG,bool isTailCall,unsigned ParamSize)2274 static int CalculateTailCallSPDiff(SelectionDAG& DAG, bool isTailCall,
2275                                    unsigned ParamSize) {
2276 
2277   if (!isTailCall) return 0;
2278 
2279   PPCFunctionInfo *FI = DAG.getMachineFunction().getInfo<PPCFunctionInfo>();
2280   unsigned CallerMinReservedArea = FI->getMinReservedArea();
2281   int SPDiff = (int)CallerMinReservedArea - (int)ParamSize;
2282   // Remember only if the new adjustement is bigger.
2283   if (SPDiff < FI->getTailCallSPDelta())
2284     FI->setTailCallSPDelta(SPDiff);
2285 
2286   return SPDiff;
2287 }
2288 
2289 /// IsEligibleForTailCallOptimization - Check whether the call is eligible
2290 /// for tail call optimization. Targets which want to do tail call
2291 /// optimization should implement this function.
2292 bool
IsEligibleForTailCallOptimization(SDValue Callee,CallingConv::ID CalleeCC,bool isVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,SelectionDAG & DAG) const2293 PPCTargetLowering::IsEligibleForTailCallOptimization(SDValue Callee,
2294                                                      CallingConv::ID CalleeCC,
2295                                                      bool isVarArg,
2296                                       const SmallVectorImpl<ISD::InputArg> &Ins,
2297                                                      SelectionDAG& DAG) const {
2298   if (!GuaranteedTailCallOpt)
2299     return false;
2300 
2301   // Variable argument functions are not supported.
2302   if (isVarArg)
2303     return false;
2304 
2305   MachineFunction &MF = DAG.getMachineFunction();
2306   CallingConv::ID CallerCC = MF.getFunction()->getCallingConv();
2307   if (CalleeCC == CallingConv::Fast && CallerCC == CalleeCC) {
2308     // Functions containing by val parameters are not supported.
2309     for (unsigned i = 0; i != Ins.size(); i++) {
2310        ISD::ArgFlagsTy Flags = Ins[i].Flags;
2311        if (Flags.isByVal()) return false;
2312     }
2313 
2314     // Non PIC/GOT  tail calls are supported.
2315     if (getTargetMachine().getRelocationModel() != Reloc::PIC_)
2316       return true;
2317 
2318     // At the moment we can only do local tail calls (in same module, hidden
2319     // or protected) if we are generating PIC.
2320     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
2321       return G->getGlobal()->hasHiddenVisibility()
2322           || G->getGlobal()->hasProtectedVisibility();
2323   }
2324 
2325   return false;
2326 }
2327 
2328 /// isCallCompatibleAddress - Return the immediate to use if the specified
2329 /// 32-bit value is representable in the immediate field of a BxA instruction.
isBLACompatibleAddress(SDValue Op,SelectionDAG & DAG)2330 static SDNode *isBLACompatibleAddress(SDValue Op, SelectionDAG &DAG) {
2331   ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
2332   if (!C) return 0;
2333 
2334   int Addr = C->getZExtValue();
2335   if ((Addr & 3) != 0 ||  // Low 2 bits are implicitly zero.
2336       (Addr << 6 >> 6) != Addr)
2337     return 0;  // Top 6 bits have to be sext of immediate.
2338 
2339   return DAG.getConstant((int)C->getZExtValue() >> 2,
2340                          DAG.getTargetLoweringInfo().getPointerTy()).getNode();
2341 }
2342 
2343 namespace {
2344 
2345 struct TailCallArgumentInfo {
2346   SDValue Arg;
2347   SDValue FrameIdxOp;
2348   int       FrameIdx;
2349 
TailCallArgumentInfo__anon87f971c30111::TailCallArgumentInfo2350   TailCallArgumentInfo() : FrameIdx(0) {}
2351 };
2352 
2353 }
2354 
2355 /// StoreTailCallArgumentsToStackSlot - Stores arguments to their stack slot.
2356 static void
StoreTailCallArgumentsToStackSlot(SelectionDAG & DAG,SDValue Chain,const SmallVector<TailCallArgumentInfo,8> & TailCallArgs,SmallVector<SDValue,8> & MemOpChains,DebugLoc dl)2357 StoreTailCallArgumentsToStackSlot(SelectionDAG &DAG,
2358                                            SDValue Chain,
2359                    const SmallVector<TailCallArgumentInfo, 8> &TailCallArgs,
2360                    SmallVector<SDValue, 8> &MemOpChains,
2361                    DebugLoc dl) {
2362   for (unsigned i = 0, e = TailCallArgs.size(); i != e; ++i) {
2363     SDValue Arg = TailCallArgs[i].Arg;
2364     SDValue FIN = TailCallArgs[i].FrameIdxOp;
2365     int FI = TailCallArgs[i].FrameIdx;
2366     // Store relative to framepointer.
2367     MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, FIN,
2368                                        MachinePointerInfo::getFixedStack(FI),
2369                                        false, false, 0));
2370   }
2371 }
2372 
2373 /// EmitTailCallStoreFPAndRetAddr - Move the frame pointer and return address to
2374 /// the appropriate stack slot for the tail call optimized function call.
EmitTailCallStoreFPAndRetAddr(SelectionDAG & DAG,MachineFunction & MF,SDValue Chain,SDValue OldRetAddr,SDValue OldFP,int SPDiff,bool isPPC64,bool isDarwinABI,DebugLoc dl)2375 static SDValue EmitTailCallStoreFPAndRetAddr(SelectionDAG &DAG,
2376                                                MachineFunction &MF,
2377                                                SDValue Chain,
2378                                                SDValue OldRetAddr,
2379                                                SDValue OldFP,
2380                                                int SPDiff,
2381                                                bool isPPC64,
2382                                                bool isDarwinABI,
2383                                                DebugLoc dl) {
2384   if (SPDiff) {
2385     // Calculate the new stack slot for the return address.
2386     int SlotSize = isPPC64 ? 8 : 4;
2387     int NewRetAddrLoc = SPDiff + PPCFrameLowering::getReturnSaveOffset(isPPC64,
2388                                                                    isDarwinABI);
2389     int NewRetAddr = MF.getFrameInfo()->CreateFixedObject(SlotSize,
2390                                                           NewRetAddrLoc, true);
2391     EVT VT = isPPC64 ? MVT::i64 : MVT::i32;
2392     SDValue NewRetAddrFrIdx = DAG.getFrameIndex(NewRetAddr, VT);
2393     Chain = DAG.getStore(Chain, dl, OldRetAddr, NewRetAddrFrIdx,
2394                          MachinePointerInfo::getFixedStack(NewRetAddr),
2395                          false, false, 0);
2396 
2397     // When using the 32/64-bit SVR4 ABI there is no need to move the FP stack
2398     // slot as the FP is never overwritten.
2399     if (isDarwinABI) {
2400       int NewFPLoc =
2401         SPDiff + PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
2402       int NewFPIdx = MF.getFrameInfo()->CreateFixedObject(SlotSize, NewFPLoc,
2403                                                           true);
2404       SDValue NewFramePtrIdx = DAG.getFrameIndex(NewFPIdx, VT);
2405       Chain = DAG.getStore(Chain, dl, OldFP, NewFramePtrIdx,
2406                            MachinePointerInfo::getFixedStack(NewFPIdx),
2407                            false, false, 0);
2408     }
2409   }
2410   return Chain;
2411 }
2412 
2413 /// CalculateTailCallArgDest - Remember Argument for later processing. Calculate
2414 /// the position of the argument.
2415 static void
CalculateTailCallArgDest(SelectionDAG & DAG,MachineFunction & MF,bool isPPC64,SDValue Arg,int SPDiff,unsigned ArgOffset,SmallVector<TailCallArgumentInfo,8> & TailCallArguments)2416 CalculateTailCallArgDest(SelectionDAG &DAG, MachineFunction &MF, bool isPPC64,
2417                          SDValue Arg, int SPDiff, unsigned ArgOffset,
2418                       SmallVector<TailCallArgumentInfo, 8>& TailCallArguments) {
2419   int Offset = ArgOffset + SPDiff;
2420   uint32_t OpSize = (Arg.getValueType().getSizeInBits()+7)/8;
2421   int FI = MF.getFrameInfo()->CreateFixedObject(OpSize, Offset, true);
2422   EVT VT = isPPC64 ? MVT::i64 : MVT::i32;
2423   SDValue FIN = DAG.getFrameIndex(FI, VT);
2424   TailCallArgumentInfo Info;
2425   Info.Arg = Arg;
2426   Info.FrameIdxOp = FIN;
2427   Info.FrameIdx = FI;
2428   TailCallArguments.push_back(Info);
2429 }
2430 
2431 /// EmitTCFPAndRetAddrLoad - Emit load from frame pointer and return address
2432 /// stack slot. Returns the chain as result and the loaded frame pointers in
2433 /// LROpOut/FPOpout. Used when tail calling.
EmitTailCallLoadFPAndRetAddr(SelectionDAG & DAG,int SPDiff,SDValue Chain,SDValue & LROpOut,SDValue & FPOpOut,bool isDarwinABI,DebugLoc dl) const2434 SDValue PPCTargetLowering::EmitTailCallLoadFPAndRetAddr(SelectionDAG & DAG,
2435                                                         int SPDiff,
2436                                                         SDValue Chain,
2437                                                         SDValue &LROpOut,
2438                                                         SDValue &FPOpOut,
2439                                                         bool isDarwinABI,
2440                                                         DebugLoc dl) const {
2441   if (SPDiff) {
2442     // Load the LR and FP stack slot for later adjusting.
2443     EVT VT = PPCSubTarget.isPPC64() ? MVT::i64 : MVT::i32;
2444     LROpOut = getReturnAddrFrameIndex(DAG);
2445     LROpOut = DAG.getLoad(VT, dl, Chain, LROpOut, MachinePointerInfo(),
2446                           false, false, 0);
2447     Chain = SDValue(LROpOut.getNode(), 1);
2448 
2449     // When using the 32/64-bit SVR4 ABI there is no need to load the FP stack
2450     // slot as the FP is never overwritten.
2451     if (isDarwinABI) {
2452       FPOpOut = getFramePointerFrameIndex(DAG);
2453       FPOpOut = DAG.getLoad(VT, dl, Chain, FPOpOut, MachinePointerInfo(),
2454                             false, false, 0);
2455       Chain = SDValue(FPOpOut.getNode(), 1);
2456     }
2457   }
2458   return Chain;
2459 }
2460 
2461 /// CreateCopyOfByValArgument - Make a copy of an aggregate at address specified
2462 /// by "Src" to address "Dst" of size "Size".  Alignment information is
2463 /// specified by the specific parameter attribute. The copy will be passed as
2464 /// a byval function parameter.
2465 /// Sometimes what we are copying is the end of a larger object, the part that
2466 /// does not fit in registers.
2467 static SDValue
CreateCopyOfByValArgument(SDValue Src,SDValue Dst,SDValue Chain,ISD::ArgFlagsTy Flags,SelectionDAG & DAG,DebugLoc dl)2468 CreateCopyOfByValArgument(SDValue Src, SDValue Dst, SDValue Chain,
2469                           ISD::ArgFlagsTy Flags, SelectionDAG &DAG,
2470                           DebugLoc dl) {
2471   SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), MVT::i32);
2472   return DAG.getMemcpy(Chain, dl, Dst, Src, SizeNode, Flags.getByValAlign(),
2473                        false, false, MachinePointerInfo(0),
2474                        MachinePointerInfo(0));
2475 }
2476 
2477 /// LowerMemOpCallTo - Store the argument to the stack or remember it in case of
2478 /// tail calls.
2479 static void
LowerMemOpCallTo(SelectionDAG & DAG,MachineFunction & MF,SDValue Chain,SDValue Arg,SDValue PtrOff,int SPDiff,unsigned ArgOffset,bool isPPC64,bool isTailCall,bool isVector,SmallVector<SDValue,8> & MemOpChains,SmallVector<TailCallArgumentInfo,8> & TailCallArguments,DebugLoc dl)2480 LowerMemOpCallTo(SelectionDAG &DAG, MachineFunction &MF, SDValue Chain,
2481                  SDValue Arg, SDValue PtrOff, int SPDiff,
2482                  unsigned ArgOffset, bool isPPC64, bool isTailCall,
2483                  bool isVector, SmallVector<SDValue, 8> &MemOpChains,
2484                  SmallVector<TailCallArgumentInfo, 8> &TailCallArguments,
2485                  DebugLoc dl) {
2486   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
2487   if (!isTailCall) {
2488     if (isVector) {
2489       SDValue StackPtr;
2490       if (isPPC64)
2491         StackPtr = DAG.getRegister(PPC::X1, MVT::i64);
2492       else
2493         StackPtr = DAG.getRegister(PPC::R1, MVT::i32);
2494       PtrOff = DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr,
2495                            DAG.getConstant(ArgOffset, PtrVT));
2496     }
2497     MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
2498                                        MachinePointerInfo(), false, false, 0));
2499   // Calculate and remember argument location.
2500   } else CalculateTailCallArgDest(DAG, MF, isPPC64, Arg, SPDiff, ArgOffset,
2501                                   TailCallArguments);
2502 }
2503 
2504 static
PrepareTailCall(SelectionDAG & DAG,SDValue & InFlag,SDValue & Chain,DebugLoc dl,bool isPPC64,int SPDiff,unsigned NumBytes,SDValue LROp,SDValue FPOp,bool isDarwinABI,SmallVector<TailCallArgumentInfo,8> & TailCallArguments)2505 void PrepareTailCall(SelectionDAG &DAG, SDValue &InFlag, SDValue &Chain,
2506                      DebugLoc dl, bool isPPC64, int SPDiff, unsigned NumBytes,
2507                      SDValue LROp, SDValue FPOp, bool isDarwinABI,
2508                      SmallVector<TailCallArgumentInfo, 8> &TailCallArguments) {
2509   MachineFunction &MF = DAG.getMachineFunction();
2510 
2511   // Emit a sequence of copyto/copyfrom virtual registers for arguments that
2512   // might overwrite each other in case of tail call optimization.
2513   SmallVector<SDValue, 8> MemOpChains2;
2514   // Do not flag preceding copytoreg stuff together with the following stuff.
2515   InFlag = SDValue();
2516   StoreTailCallArgumentsToStackSlot(DAG, Chain, TailCallArguments,
2517                                     MemOpChains2, dl);
2518   if (!MemOpChains2.empty())
2519     Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
2520                         &MemOpChains2[0], MemOpChains2.size());
2521 
2522   // Store the return address to the appropriate stack slot.
2523   Chain = EmitTailCallStoreFPAndRetAddr(DAG, MF, Chain, LROp, FPOp, SPDiff,
2524                                         isPPC64, isDarwinABI, dl);
2525 
2526   // Emit callseq_end just before tailcall node.
2527   Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true),
2528                              DAG.getIntPtrConstant(0, true), InFlag);
2529   InFlag = Chain.getValue(1);
2530 }
2531 
2532 static
PrepareCall(SelectionDAG & DAG,SDValue & Callee,SDValue & InFlag,SDValue & Chain,DebugLoc dl,int SPDiff,bool isTailCall,SmallVector<std::pair<unsigned,SDValue>,8> & RegsToPass,SmallVector<SDValue,8> & Ops,std::vector<EVT> & NodeTys,const PPCSubtarget & PPCSubTarget)2533 unsigned PrepareCall(SelectionDAG &DAG, SDValue &Callee, SDValue &InFlag,
2534                      SDValue &Chain, DebugLoc dl, int SPDiff, bool isTailCall,
2535                      SmallVector<std::pair<unsigned, SDValue>, 8> &RegsToPass,
2536                      SmallVector<SDValue, 8> &Ops, std::vector<EVT> &NodeTys,
2537                      const PPCSubtarget &PPCSubTarget) {
2538 
2539   bool isPPC64 = PPCSubTarget.isPPC64();
2540   bool isSVR4ABI = PPCSubTarget.isSVR4ABI();
2541 
2542   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
2543   NodeTys.push_back(MVT::Other);   // Returns a chain
2544   NodeTys.push_back(MVT::Glue);    // Returns a flag for retval copy to use.
2545 
2546   unsigned CallOpc = isSVR4ABI ? PPCISD::CALL_SVR4 : PPCISD::CALL_Darwin;
2547 
2548   bool needIndirectCall = true;
2549   if (SDNode *Dest = isBLACompatibleAddress(Callee, DAG)) {
2550     // If this is an absolute destination address, use the munged value.
2551     Callee = SDValue(Dest, 0);
2552     needIndirectCall = false;
2553   }
2554 
2555   if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2556     // XXX Work around for http://llvm.org/bugs/show_bug.cgi?id=5201
2557     // Use indirect calls for ALL functions calls in JIT mode, since the
2558     // far-call stubs may be outside relocation limits for a BL instruction.
2559     if (!DAG.getTarget().getSubtarget<PPCSubtarget>().isJITCodeModel()) {
2560       unsigned OpFlags = 0;
2561       if (DAG.getTarget().getRelocationModel() != Reloc::Static &&
2562           (PPCSubTarget.getTargetTriple().isMacOSX() &&
2563            PPCSubTarget.getTargetTriple().isMacOSXVersionLT(10, 5)) &&
2564           (G->getGlobal()->isDeclaration() ||
2565            G->getGlobal()->isWeakForLinker())) {
2566         // PC-relative references to external symbols should go through $stub,
2567         // unless we're building with the leopard linker or later, which
2568         // automatically synthesizes these stubs.
2569         OpFlags = PPCII::MO_DARWIN_STUB;
2570       }
2571 
2572       // If the callee is a GlobalAddress/ExternalSymbol node (quite common,
2573       // every direct call is) turn it into a TargetGlobalAddress /
2574       // TargetExternalSymbol node so that legalize doesn't hack it.
2575       Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl,
2576                                           Callee.getValueType(),
2577                                           0, OpFlags);
2578       needIndirectCall = false;
2579     }
2580   }
2581 
2582   if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2583     unsigned char OpFlags = 0;
2584 
2585     if (DAG.getTarget().getRelocationModel() != Reloc::Static &&
2586         (PPCSubTarget.getTargetTriple().isMacOSX() &&
2587          PPCSubTarget.getTargetTriple().isMacOSXVersionLT(10, 5))) {
2588       // PC-relative references to external symbols should go through $stub,
2589       // unless we're building with the leopard linker or later, which
2590       // automatically synthesizes these stubs.
2591       OpFlags = PPCII::MO_DARWIN_STUB;
2592     }
2593 
2594     Callee = DAG.getTargetExternalSymbol(S->getSymbol(), Callee.getValueType(),
2595                                          OpFlags);
2596     needIndirectCall = false;
2597   }
2598 
2599   if (needIndirectCall) {
2600     // Otherwise, this is an indirect call.  We have to use a MTCTR/BCTRL pair
2601     // to do the call, we can't use PPCISD::CALL.
2602     SDValue MTCTROps[] = {Chain, Callee, InFlag};
2603 
2604     if (isSVR4ABI && isPPC64) {
2605       // Function pointers in the 64-bit SVR4 ABI do not point to the function
2606       // entry point, but to the function descriptor (the function entry point
2607       // address is part of the function descriptor though).
2608       // The function descriptor is a three doubleword structure with the
2609       // following fields: function entry point, TOC base address and
2610       // environment pointer.
2611       // Thus for a call through a function pointer, the following actions need
2612       // to be performed:
2613       //   1. Save the TOC of the caller in the TOC save area of its stack
2614       //      frame (this is done in LowerCall_Darwin()).
2615       //   2. Load the address of the function entry point from the function
2616       //      descriptor.
2617       //   3. Load the TOC of the callee from the function descriptor into r2.
2618       //   4. Load the environment pointer from the function descriptor into
2619       //      r11.
2620       //   5. Branch to the function entry point address.
2621       //   6. On return of the callee, the TOC of the caller needs to be
2622       //      restored (this is done in FinishCall()).
2623       //
2624       // All those operations are flagged together to ensure that no other
2625       // operations can be scheduled in between. E.g. without flagging the
2626       // operations together, a TOC access in the caller could be scheduled
2627       // between the load of the callee TOC and the branch to the callee, which
2628       // results in the TOC access going through the TOC of the callee instead
2629       // of going through the TOC of the caller, which leads to incorrect code.
2630 
2631       // Load the address of the function entry point from the function
2632       // descriptor.
2633       SDVTList VTs = DAG.getVTList(MVT::i64, MVT::Other, MVT::Glue);
2634       SDValue LoadFuncPtr = DAG.getNode(PPCISD::LOAD, dl, VTs, MTCTROps,
2635                                         InFlag.getNode() ? 3 : 2);
2636       Chain = LoadFuncPtr.getValue(1);
2637       InFlag = LoadFuncPtr.getValue(2);
2638 
2639       // Load environment pointer into r11.
2640       // Offset of the environment pointer within the function descriptor.
2641       SDValue PtrOff = DAG.getIntPtrConstant(16);
2642 
2643       SDValue AddPtr = DAG.getNode(ISD::ADD, dl, MVT::i64, Callee, PtrOff);
2644       SDValue LoadEnvPtr = DAG.getNode(PPCISD::LOAD, dl, VTs, Chain, AddPtr,
2645                                        InFlag);
2646       Chain = LoadEnvPtr.getValue(1);
2647       InFlag = LoadEnvPtr.getValue(2);
2648 
2649       SDValue EnvVal = DAG.getCopyToReg(Chain, dl, PPC::X11, LoadEnvPtr,
2650                                         InFlag);
2651       Chain = EnvVal.getValue(0);
2652       InFlag = EnvVal.getValue(1);
2653 
2654       // Load TOC of the callee into r2. We are using a target-specific load
2655       // with r2 hard coded, because the result of a target-independent load
2656       // would never go directly into r2, since r2 is a reserved register (which
2657       // prevents the register allocator from allocating it), resulting in an
2658       // additional register being allocated and an unnecessary move instruction
2659       // being generated.
2660       VTs = DAG.getVTList(MVT::Other, MVT::Glue);
2661       SDValue LoadTOCPtr = DAG.getNode(PPCISD::LOAD_TOC, dl, VTs, Chain,
2662                                        Callee, InFlag);
2663       Chain = LoadTOCPtr.getValue(0);
2664       InFlag = LoadTOCPtr.getValue(1);
2665 
2666       MTCTROps[0] = Chain;
2667       MTCTROps[1] = LoadFuncPtr;
2668       MTCTROps[2] = InFlag;
2669     }
2670 
2671     Chain = DAG.getNode(PPCISD::MTCTR, dl, NodeTys, MTCTROps,
2672                         2 + (InFlag.getNode() != 0));
2673     InFlag = Chain.getValue(1);
2674 
2675     NodeTys.clear();
2676     NodeTys.push_back(MVT::Other);
2677     NodeTys.push_back(MVT::Glue);
2678     Ops.push_back(Chain);
2679     CallOpc = isSVR4ABI ? PPCISD::BCTRL_SVR4 : PPCISD::BCTRL_Darwin;
2680     Callee.setNode(0);
2681     // Add CTR register as callee so a bctr can be emitted later.
2682     if (isTailCall)
2683       Ops.push_back(DAG.getRegister(isPPC64 ? PPC::CTR8 : PPC::CTR, PtrVT));
2684   }
2685 
2686   // If this is a direct call, pass the chain and the callee.
2687   if (Callee.getNode()) {
2688     Ops.push_back(Chain);
2689     Ops.push_back(Callee);
2690   }
2691   // If this is a tail call add stack pointer delta.
2692   if (isTailCall)
2693     Ops.push_back(DAG.getConstant(SPDiff, MVT::i32));
2694 
2695   // Add argument registers to the end of the list so that they are known live
2696   // into the call.
2697   for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2698     Ops.push_back(DAG.getRegister(RegsToPass[i].first,
2699                                   RegsToPass[i].second.getValueType()));
2700 
2701   return CallOpc;
2702 }
2703 
2704 SDValue
LowerCallResult(SDValue Chain,SDValue InFlag,CallingConv::ID CallConv,bool isVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const2705 PPCTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
2706                                    CallingConv::ID CallConv, bool isVarArg,
2707                                    const SmallVectorImpl<ISD::InputArg> &Ins,
2708                                    DebugLoc dl, SelectionDAG &DAG,
2709                                    SmallVectorImpl<SDValue> &InVals) const {
2710 
2711   SmallVector<CCValAssign, 16> RVLocs;
2712   CCState CCRetInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2713 		    getTargetMachine(), RVLocs, *DAG.getContext());
2714   CCRetInfo.AnalyzeCallResult(Ins, RetCC_PPC);
2715 
2716   // Copy all of the result registers out of their specified physreg.
2717   for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
2718     CCValAssign &VA = RVLocs[i];
2719     EVT VT = VA.getValVT();
2720     assert(VA.isRegLoc() && "Can only return in registers!");
2721     Chain = DAG.getCopyFromReg(Chain, dl,
2722                                VA.getLocReg(), VT, InFlag).getValue(1);
2723     InVals.push_back(Chain.getValue(0));
2724     InFlag = Chain.getValue(2);
2725   }
2726 
2727   return Chain;
2728 }
2729 
2730 SDValue
FinishCall(CallingConv::ID CallConv,DebugLoc dl,bool isTailCall,bool isVarArg,SelectionDAG & DAG,SmallVector<std::pair<unsigned,SDValue>,8> & RegsToPass,SDValue InFlag,SDValue Chain,SDValue & Callee,int SPDiff,unsigned NumBytes,const SmallVectorImpl<ISD::InputArg> & Ins,SmallVectorImpl<SDValue> & InVals) const2731 PPCTargetLowering::FinishCall(CallingConv::ID CallConv, DebugLoc dl,
2732                               bool isTailCall, bool isVarArg,
2733                               SelectionDAG &DAG,
2734                               SmallVector<std::pair<unsigned, SDValue>, 8>
2735                                 &RegsToPass,
2736                               SDValue InFlag, SDValue Chain,
2737                               SDValue &Callee,
2738                               int SPDiff, unsigned NumBytes,
2739                               const SmallVectorImpl<ISD::InputArg> &Ins,
2740                               SmallVectorImpl<SDValue> &InVals) const {
2741   std::vector<EVT> NodeTys;
2742   SmallVector<SDValue, 8> Ops;
2743   unsigned CallOpc = PrepareCall(DAG, Callee, InFlag, Chain, dl, SPDiff,
2744                                  isTailCall, RegsToPass, Ops, NodeTys,
2745                                  PPCSubTarget);
2746 
2747   // When performing tail call optimization the callee pops its arguments off
2748   // the stack. Account for this here so these bytes can be pushed back on in
2749   // PPCRegisterInfo::eliminateCallFramePseudoInstr.
2750   int BytesCalleePops =
2751     (CallConv==CallingConv::Fast && GuaranteedTailCallOpt) ? NumBytes : 0;
2752 
2753   if (InFlag.getNode())
2754     Ops.push_back(InFlag);
2755 
2756   // Emit tail call.
2757   if (isTailCall) {
2758     // If this is the first return lowered for this function, add the regs
2759     // to the liveout set for the function.
2760     if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
2761       SmallVector<CCValAssign, 16> RVLocs;
2762       CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2763 		     getTargetMachine(), RVLocs, *DAG.getContext());
2764       CCInfo.AnalyzeCallResult(Ins, RetCC_PPC);
2765       for (unsigned i = 0; i != RVLocs.size(); ++i)
2766         DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
2767     }
2768 
2769     assert(((Callee.getOpcode() == ISD::Register &&
2770              cast<RegisterSDNode>(Callee)->getReg() == PPC::CTR) ||
2771             Callee.getOpcode() == ISD::TargetExternalSymbol ||
2772             Callee.getOpcode() == ISD::TargetGlobalAddress ||
2773             isa<ConstantSDNode>(Callee)) &&
2774     "Expecting an global address, external symbol, absolute value or register");
2775 
2776     return DAG.getNode(PPCISD::TC_RETURN, dl, MVT::Other, &Ops[0], Ops.size());
2777   }
2778 
2779   Chain = DAG.getNode(CallOpc, dl, NodeTys, &Ops[0], Ops.size());
2780   InFlag = Chain.getValue(1);
2781 
2782   // Add a NOP immediately after the branch instruction when using the 64-bit
2783   // SVR4 ABI. At link time, if caller and callee are in a different module and
2784   // thus have a different TOC, the call will be replaced with a call to a stub
2785   // function which saves the current TOC, loads the TOC of the callee and
2786   // branches to the callee. The NOP will be replaced with a load instruction
2787   // which restores the TOC of the caller from the TOC save slot of the current
2788   // stack frame. If caller and callee belong to the same module (and have the
2789   // same TOC), the NOP will remain unchanged.
2790   if (!isTailCall && PPCSubTarget.isSVR4ABI()&& PPCSubTarget.isPPC64()) {
2791     SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue);
2792     if (CallOpc == PPCISD::BCTRL_SVR4) {
2793       // This is a call through a function pointer.
2794       // Restore the caller TOC from the save area into R2.
2795       // See PrepareCall() for more information about calls through function
2796       // pointers in the 64-bit SVR4 ABI.
2797       // We are using a target-specific load with r2 hard coded, because the
2798       // result of a target-independent load would never go directly into r2,
2799       // since r2 is a reserved register (which prevents the register allocator
2800       // from allocating it), resulting in an additional register being
2801       // allocated and an unnecessary move instruction being generated.
2802       Chain = DAG.getNode(PPCISD::TOC_RESTORE, dl, VTs, Chain, InFlag);
2803       InFlag = Chain.getValue(1);
2804     } else {
2805       // Otherwise insert NOP.
2806       InFlag = DAG.getNode(PPCISD::NOP, dl, MVT::Glue, InFlag);
2807     }
2808   }
2809 
2810   Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true),
2811                              DAG.getIntPtrConstant(BytesCalleePops, true),
2812                              InFlag);
2813   if (!Ins.empty())
2814     InFlag = Chain.getValue(1);
2815 
2816   return LowerCallResult(Chain, InFlag, CallConv, isVarArg,
2817                          Ins, dl, DAG, InVals);
2818 }
2819 
2820 SDValue
LowerCall(SDValue Chain,SDValue Callee,CallingConv::ID CallConv,bool isVarArg,bool & isTailCall,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const2821 PPCTargetLowering::LowerCall(SDValue Chain, SDValue Callee,
2822                              CallingConv::ID CallConv, bool isVarArg,
2823                              bool &isTailCall,
2824                              const SmallVectorImpl<ISD::OutputArg> &Outs,
2825                              const SmallVectorImpl<SDValue> &OutVals,
2826                              const SmallVectorImpl<ISD::InputArg> &Ins,
2827                              DebugLoc dl, SelectionDAG &DAG,
2828                              SmallVectorImpl<SDValue> &InVals) const {
2829   if (isTailCall)
2830     isTailCall = IsEligibleForTailCallOptimization(Callee, CallConv, isVarArg,
2831                                                    Ins, DAG);
2832 
2833   if (PPCSubTarget.isSVR4ABI() && !PPCSubTarget.isPPC64())
2834     return LowerCall_SVR4(Chain, Callee, CallConv, isVarArg,
2835                           isTailCall, Outs, OutVals, Ins,
2836                           dl, DAG, InVals);
2837 
2838   return LowerCall_Darwin(Chain, Callee, CallConv, isVarArg,
2839                           isTailCall, Outs, OutVals, Ins,
2840                           dl, DAG, InVals);
2841 }
2842 
2843 SDValue
LowerCall_SVR4(SDValue Chain,SDValue Callee,CallingConv::ID CallConv,bool isVarArg,bool isTailCall,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const2844 PPCTargetLowering::LowerCall_SVR4(SDValue Chain, SDValue Callee,
2845                                   CallingConv::ID CallConv, bool isVarArg,
2846                                   bool isTailCall,
2847                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
2848                                   const SmallVectorImpl<SDValue> &OutVals,
2849                                   const SmallVectorImpl<ISD::InputArg> &Ins,
2850                                   DebugLoc dl, SelectionDAG &DAG,
2851                                   SmallVectorImpl<SDValue> &InVals) const {
2852   // See PPCTargetLowering::LowerFormalArguments_SVR4() for a description
2853   // of the 32-bit SVR4 ABI stack frame layout.
2854 
2855   assert((CallConv == CallingConv::C ||
2856           CallConv == CallingConv::Fast) && "Unknown calling convention!");
2857 
2858   unsigned PtrByteSize = 4;
2859 
2860   MachineFunction &MF = DAG.getMachineFunction();
2861 
2862   // Mark this function as potentially containing a function that contains a
2863   // tail call. As a consequence the frame pointer will be used for dynamicalloc
2864   // and restoring the callers stack pointer in this functions epilog. This is
2865   // done because by tail calling the called function might overwrite the value
2866   // in this function's (MF) stack pointer stack slot 0(SP).
2867   if (GuaranteedTailCallOpt && CallConv==CallingConv::Fast)
2868     MF.getInfo<PPCFunctionInfo>()->setHasFastCall();
2869 
2870   // Count how many bytes are to be pushed on the stack, including the linkage
2871   // area, parameter list area and the part of the local variable space which
2872   // contains copies of aggregates which are passed by value.
2873 
2874   // Assign locations to all of the outgoing arguments.
2875   SmallVector<CCValAssign, 16> ArgLocs;
2876   CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2877 		 getTargetMachine(), ArgLocs, *DAG.getContext());
2878 
2879   // Reserve space for the linkage area on the stack.
2880   CCInfo.AllocateStack(PPCFrameLowering::getLinkageSize(false, false), PtrByteSize);
2881 
2882   if (isVarArg) {
2883     // Handle fixed and variable vector arguments differently.
2884     // Fixed vector arguments go into registers as long as registers are
2885     // available. Variable vector arguments always go into memory.
2886     unsigned NumArgs = Outs.size();
2887 
2888     for (unsigned i = 0; i != NumArgs; ++i) {
2889       MVT ArgVT = Outs[i].VT;
2890       ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
2891       bool Result;
2892 
2893       if (Outs[i].IsFixed) {
2894         Result = CC_PPC_SVR4(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags,
2895                              CCInfo);
2896       } else {
2897         Result = CC_PPC_SVR4_VarArg(i, ArgVT, ArgVT, CCValAssign::Full,
2898                                     ArgFlags, CCInfo);
2899       }
2900 
2901       if (Result) {
2902 #ifndef NDEBUG
2903         errs() << "Call operand #" << i << " has unhandled type "
2904              << EVT(ArgVT).getEVTString() << "\n";
2905 #endif
2906         llvm_unreachable(0);
2907       }
2908     }
2909   } else {
2910     // All arguments are treated the same.
2911     CCInfo.AnalyzeCallOperands(Outs, CC_PPC_SVR4);
2912   }
2913 
2914   // Assign locations to all of the outgoing aggregate by value arguments.
2915   SmallVector<CCValAssign, 16> ByValArgLocs;
2916   CCState CCByValInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2917 		      getTargetMachine(), ByValArgLocs, *DAG.getContext());
2918 
2919   // Reserve stack space for the allocations in CCInfo.
2920   CCByValInfo.AllocateStack(CCInfo.getNextStackOffset(), PtrByteSize);
2921 
2922   CCByValInfo.AnalyzeCallOperands(Outs, CC_PPC_SVR4_ByVal);
2923 
2924   // Size of the linkage area, parameter list area and the part of the local
2925   // space variable where copies of aggregates which are passed by value are
2926   // stored.
2927   unsigned NumBytes = CCByValInfo.getNextStackOffset();
2928 
2929   // Calculate by how many bytes the stack has to be adjusted in case of tail
2930   // call optimization.
2931   int SPDiff = CalculateTailCallSPDiff(DAG, isTailCall, NumBytes);
2932 
2933   // Adjust the stack pointer for the new arguments...
2934   // These operations are automatically eliminated by the prolog/epilog pass
2935   Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(NumBytes, true));
2936   SDValue CallSeqStart = Chain;
2937 
2938   // Load the return address and frame pointer so it can be moved somewhere else
2939   // later.
2940   SDValue LROp, FPOp;
2941   Chain = EmitTailCallLoadFPAndRetAddr(DAG, SPDiff, Chain, LROp, FPOp, false,
2942                                        dl);
2943 
2944   // Set up a copy of the stack pointer for use loading and storing any
2945   // arguments that may not fit in the registers available for argument
2946   // passing.
2947   SDValue StackPtr = DAG.getRegister(PPC::R1, MVT::i32);
2948 
2949   SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
2950   SmallVector<TailCallArgumentInfo, 8> TailCallArguments;
2951   SmallVector<SDValue, 8> MemOpChains;
2952 
2953   bool seenFloatArg = false;
2954   // Walk the register/memloc assignments, inserting copies/loads.
2955   for (unsigned i = 0, j = 0, e = ArgLocs.size();
2956        i != e;
2957        ++i) {
2958     CCValAssign &VA = ArgLocs[i];
2959     SDValue Arg = OutVals[i];
2960     ISD::ArgFlagsTy Flags = Outs[i].Flags;
2961 
2962     if (Flags.isByVal()) {
2963       // Argument is an aggregate which is passed by value, thus we need to
2964       // create a copy of it in the local variable space of the current stack
2965       // frame (which is the stack frame of the caller) and pass the address of
2966       // this copy to the callee.
2967       assert((j < ByValArgLocs.size()) && "Index out of bounds!");
2968       CCValAssign &ByValVA = ByValArgLocs[j++];
2969       assert((VA.getValNo() == ByValVA.getValNo()) && "ValNo mismatch!");
2970 
2971       // Memory reserved in the local variable space of the callers stack frame.
2972       unsigned LocMemOffset = ByValVA.getLocMemOffset();
2973 
2974       SDValue PtrOff = DAG.getIntPtrConstant(LocMemOffset);
2975       PtrOff = DAG.getNode(ISD::ADD, dl, getPointerTy(), StackPtr, PtrOff);
2976 
2977       // Create a copy of the argument in the local area of the current
2978       // stack frame.
2979       SDValue MemcpyCall =
2980         CreateCopyOfByValArgument(Arg, PtrOff,
2981                                   CallSeqStart.getNode()->getOperand(0),
2982                                   Flags, DAG, dl);
2983 
2984       // This must go outside the CALLSEQ_START..END.
2985       SDValue NewCallSeqStart = DAG.getCALLSEQ_START(MemcpyCall,
2986                            CallSeqStart.getNode()->getOperand(1));
2987       DAG.ReplaceAllUsesWith(CallSeqStart.getNode(),
2988                              NewCallSeqStart.getNode());
2989       Chain = CallSeqStart = NewCallSeqStart;
2990 
2991       // Pass the address of the aggregate copy on the stack either in a
2992       // physical register or in the parameter list area of the current stack
2993       // frame to the callee.
2994       Arg = PtrOff;
2995     }
2996 
2997     if (VA.isRegLoc()) {
2998       seenFloatArg |= VA.getLocVT().isFloatingPoint();
2999       // Put argument in a physical register.
3000       RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
3001     } else {
3002       // Put argument in the parameter list area of the current stack frame.
3003       assert(VA.isMemLoc());
3004       unsigned LocMemOffset = VA.getLocMemOffset();
3005 
3006       if (!isTailCall) {
3007         SDValue PtrOff = DAG.getIntPtrConstant(LocMemOffset);
3008         PtrOff = DAG.getNode(ISD::ADD, dl, getPointerTy(), StackPtr, PtrOff);
3009 
3010         MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
3011                                            MachinePointerInfo(),
3012                                            false, false, 0));
3013       } else {
3014         // Calculate and remember argument location.
3015         CalculateTailCallArgDest(DAG, MF, false, Arg, SPDiff, LocMemOffset,
3016                                  TailCallArguments);
3017       }
3018     }
3019   }
3020 
3021   if (!MemOpChains.empty())
3022     Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
3023                         &MemOpChains[0], MemOpChains.size());
3024 
3025   // Set CR6 to true if this is a vararg call with floating args passed in
3026   // registers.
3027   if (isVarArg) {
3028     SDValue SetCR(DAG.getMachineNode(seenFloatArg ? PPC::CRSET : PPC::CRUNSET,
3029                                      dl, MVT::i32), 0);
3030     RegsToPass.push_back(std::make_pair(unsigned(PPC::CR1EQ), SetCR));
3031   }
3032 
3033   // Build a sequence of copy-to-reg nodes chained together with token chain
3034   // and flag operands which copy the outgoing args into the appropriate regs.
3035   SDValue InFlag;
3036   for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
3037     Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
3038                              RegsToPass[i].second, InFlag);
3039     InFlag = Chain.getValue(1);
3040   }
3041 
3042   if (isTailCall)
3043     PrepareTailCall(DAG, InFlag, Chain, dl, false, SPDiff, NumBytes, LROp, FPOp,
3044                     false, TailCallArguments);
3045 
3046   return FinishCall(CallConv, dl, isTailCall, isVarArg, DAG,
3047                     RegsToPass, InFlag, Chain, Callee, SPDiff, NumBytes,
3048                     Ins, InVals);
3049 }
3050 
3051 SDValue
LowerCall_Darwin(SDValue Chain,SDValue Callee,CallingConv::ID CallConv,bool isVarArg,bool isTailCall,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,const SmallVectorImpl<ISD::InputArg> & Ins,DebugLoc dl,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const3052 PPCTargetLowering::LowerCall_Darwin(SDValue Chain, SDValue Callee,
3053                                     CallingConv::ID CallConv, bool isVarArg,
3054                                     bool isTailCall,
3055                                     const SmallVectorImpl<ISD::OutputArg> &Outs,
3056                                     const SmallVectorImpl<SDValue> &OutVals,
3057                                     const SmallVectorImpl<ISD::InputArg> &Ins,
3058                                     DebugLoc dl, SelectionDAG &DAG,
3059                                     SmallVectorImpl<SDValue> &InVals) const {
3060 
3061   unsigned NumOps  = Outs.size();
3062 
3063   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3064   bool isPPC64 = PtrVT == MVT::i64;
3065   unsigned PtrByteSize = isPPC64 ? 8 : 4;
3066 
3067   MachineFunction &MF = DAG.getMachineFunction();
3068 
3069   // Mark this function as potentially containing a function that contains a
3070   // tail call. As a consequence the frame pointer will be used for dynamicalloc
3071   // and restoring the callers stack pointer in this functions epilog. This is
3072   // done because by tail calling the called function might overwrite the value
3073   // in this function's (MF) stack pointer stack slot 0(SP).
3074   if (GuaranteedTailCallOpt && CallConv==CallingConv::Fast)
3075     MF.getInfo<PPCFunctionInfo>()->setHasFastCall();
3076 
3077   unsigned nAltivecParamsAtEnd = 0;
3078 
3079   // Count how many bytes are to be pushed on the stack, including the linkage
3080   // area, and parameter passing area.  We start with 24/48 bytes, which is
3081   // prereserved space for [SP][CR][LR][3 x unused].
3082   unsigned NumBytes =
3083     CalculateParameterAndLinkageAreaSize(DAG, isPPC64, isVarArg, CallConv,
3084                                          Outs, OutVals,
3085                                          nAltivecParamsAtEnd);
3086 
3087   // Calculate by how many bytes the stack has to be adjusted in case of tail
3088   // call optimization.
3089   int SPDiff = CalculateTailCallSPDiff(DAG, isTailCall, NumBytes);
3090 
3091   // To protect arguments on the stack from being clobbered in a tail call,
3092   // force all the loads to happen before doing any other lowering.
3093   if (isTailCall)
3094     Chain = DAG.getStackArgumentTokenFactor(Chain);
3095 
3096   // Adjust the stack pointer for the new arguments...
3097   // These operations are automatically eliminated by the prolog/epilog pass
3098   Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(NumBytes, true));
3099   SDValue CallSeqStart = Chain;
3100 
3101   // Load the return address and frame pointer so it can be move somewhere else
3102   // later.
3103   SDValue LROp, FPOp;
3104   Chain = EmitTailCallLoadFPAndRetAddr(DAG, SPDiff, Chain, LROp, FPOp, true,
3105                                        dl);
3106 
3107   // Set up a copy of the stack pointer for use loading and storing any
3108   // arguments that may not fit in the registers available for argument
3109   // passing.
3110   SDValue StackPtr;
3111   if (isPPC64)
3112     StackPtr = DAG.getRegister(PPC::X1, MVT::i64);
3113   else
3114     StackPtr = DAG.getRegister(PPC::R1, MVT::i32);
3115 
3116   // Figure out which arguments are going to go in registers, and which in
3117   // memory.  Also, if this is a vararg function, floating point operations
3118   // must be stored to our stack, and loaded into integer regs as well, if
3119   // any integer regs are available for argument passing.
3120   unsigned ArgOffset = PPCFrameLowering::getLinkageSize(isPPC64, true);
3121   unsigned GPR_idx = 0, FPR_idx = 0, VR_idx = 0;
3122 
3123   static const unsigned GPR_32[] = {           // 32-bit registers.
3124     PPC::R3, PPC::R4, PPC::R5, PPC::R6,
3125     PPC::R7, PPC::R8, PPC::R9, PPC::R10,
3126   };
3127   static const unsigned GPR_64[] = {           // 64-bit registers.
3128     PPC::X3, PPC::X4, PPC::X5, PPC::X6,
3129     PPC::X7, PPC::X8, PPC::X9, PPC::X10,
3130   };
3131   static const unsigned *FPR = GetFPR();
3132 
3133   static const unsigned VR[] = {
3134     PPC::V2, PPC::V3, PPC::V4, PPC::V5, PPC::V6, PPC::V7, PPC::V8,
3135     PPC::V9, PPC::V10, PPC::V11, PPC::V12, PPC::V13
3136   };
3137   const unsigned NumGPRs = array_lengthof(GPR_32);
3138   const unsigned NumFPRs = 13;
3139   const unsigned NumVRs  = array_lengthof(VR);
3140 
3141   const unsigned *GPR = isPPC64 ? GPR_64 : GPR_32;
3142 
3143   SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
3144   SmallVector<TailCallArgumentInfo, 8> TailCallArguments;
3145 
3146   SmallVector<SDValue, 8> MemOpChains;
3147   for (unsigned i = 0; i != NumOps; ++i) {
3148     SDValue Arg = OutVals[i];
3149     ISD::ArgFlagsTy Flags = Outs[i].Flags;
3150 
3151     // PtrOff will be used to store the current argument to the stack if a
3152     // register cannot be found for it.
3153     SDValue PtrOff;
3154 
3155     PtrOff = DAG.getConstant(ArgOffset, StackPtr.getValueType());
3156 
3157     PtrOff = DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr, PtrOff);
3158 
3159     // On PPC64, promote integers to 64-bit values.
3160     if (isPPC64 && Arg.getValueType() == MVT::i32) {
3161       // FIXME: Should this use ANY_EXTEND if neither sext nor zext?
3162       unsigned ExtOp = Flags.isSExt() ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
3163       Arg = DAG.getNode(ExtOp, dl, MVT::i64, Arg);
3164     }
3165 
3166     // FIXME memcpy is used way more than necessary.  Correctness first.
3167     if (Flags.isByVal()) {
3168       unsigned Size = Flags.getByValSize();
3169       if (Size==1 || Size==2) {
3170         // Very small objects are passed right-justified.
3171         // Everything else is passed left-justified.
3172         EVT VT = (Size==1) ? MVT::i8 : MVT::i16;
3173         if (GPR_idx != NumGPRs) {
3174           SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, PtrVT, Chain, Arg,
3175                                         MachinePointerInfo(), VT,
3176                                         false, false, 0);
3177           MemOpChains.push_back(Load.getValue(1));
3178           RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Load));
3179 
3180           ArgOffset += PtrByteSize;
3181         } else {
3182           SDValue Const = DAG.getConstant(4 - Size, PtrOff.getValueType());
3183           SDValue AddPtr = DAG.getNode(ISD::ADD, dl, PtrVT, PtrOff, Const);
3184           SDValue MemcpyCall = CreateCopyOfByValArgument(Arg, AddPtr,
3185                                 CallSeqStart.getNode()->getOperand(0),
3186                                 Flags, DAG, dl);
3187           // This must go outside the CALLSEQ_START..END.
3188           SDValue NewCallSeqStart = DAG.getCALLSEQ_START(MemcpyCall,
3189                                CallSeqStart.getNode()->getOperand(1));
3190           DAG.ReplaceAllUsesWith(CallSeqStart.getNode(),
3191                                  NewCallSeqStart.getNode());
3192           Chain = CallSeqStart = NewCallSeqStart;
3193           ArgOffset += PtrByteSize;
3194         }
3195         continue;
3196       }
3197       // Copy entire object into memory.  There are cases where gcc-generated
3198       // code assumes it is there, even if it could be put entirely into
3199       // registers.  (This is not what the doc says.)
3200       SDValue MemcpyCall = CreateCopyOfByValArgument(Arg, PtrOff,
3201                             CallSeqStart.getNode()->getOperand(0),
3202                             Flags, DAG, dl);
3203       // This must go outside the CALLSEQ_START..END.
3204       SDValue NewCallSeqStart = DAG.getCALLSEQ_START(MemcpyCall,
3205                            CallSeqStart.getNode()->getOperand(1));
3206       DAG.ReplaceAllUsesWith(CallSeqStart.getNode(), NewCallSeqStart.getNode());
3207       Chain = CallSeqStart = NewCallSeqStart;
3208       // And copy the pieces of it that fit into registers.
3209       for (unsigned j=0; j<Size; j+=PtrByteSize) {
3210         SDValue Const = DAG.getConstant(j, PtrOff.getValueType());
3211         SDValue AddArg = DAG.getNode(ISD::ADD, dl, PtrVT, Arg, Const);
3212         if (GPR_idx != NumGPRs) {
3213           SDValue Load = DAG.getLoad(PtrVT, dl, Chain, AddArg,
3214                                      MachinePointerInfo(),
3215                                      false, false, 0);
3216           MemOpChains.push_back(Load.getValue(1));
3217           RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Load));
3218           ArgOffset += PtrByteSize;
3219         } else {
3220           ArgOffset += ((Size - j + PtrByteSize-1)/PtrByteSize)*PtrByteSize;
3221           break;
3222         }
3223       }
3224       continue;
3225     }
3226 
3227     switch (Arg.getValueType().getSimpleVT().SimpleTy) {
3228     default: llvm_unreachable("Unexpected ValueType for argument!");
3229     case MVT::i32:
3230     case MVT::i64:
3231       if (GPR_idx != NumGPRs) {
3232         RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Arg));
3233       } else {
3234         LowerMemOpCallTo(DAG, MF, Chain, Arg, PtrOff, SPDiff, ArgOffset,
3235                          isPPC64, isTailCall, false, MemOpChains,
3236                          TailCallArguments, dl);
3237       }
3238       ArgOffset += PtrByteSize;
3239       break;
3240     case MVT::f32:
3241     case MVT::f64:
3242       if (FPR_idx != NumFPRs) {
3243         RegsToPass.push_back(std::make_pair(FPR[FPR_idx++], Arg));
3244 
3245         if (isVarArg) {
3246           SDValue Store = DAG.getStore(Chain, dl, Arg, PtrOff,
3247                                        MachinePointerInfo(), false, false, 0);
3248           MemOpChains.push_back(Store);
3249 
3250           // Float varargs are always shadowed in available integer registers
3251           if (GPR_idx != NumGPRs) {
3252             SDValue Load = DAG.getLoad(PtrVT, dl, Store, PtrOff,
3253                                        MachinePointerInfo(), false, false, 0);
3254             MemOpChains.push_back(Load.getValue(1));
3255             RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Load));
3256           }
3257           if (GPR_idx != NumGPRs && Arg.getValueType() == MVT::f64 && !isPPC64){
3258             SDValue ConstFour = DAG.getConstant(4, PtrOff.getValueType());
3259             PtrOff = DAG.getNode(ISD::ADD, dl, PtrVT, PtrOff, ConstFour);
3260             SDValue Load = DAG.getLoad(PtrVT, dl, Store, PtrOff,
3261                                        MachinePointerInfo(),
3262                                        false, false, 0);
3263             MemOpChains.push_back(Load.getValue(1));
3264             RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Load));
3265           }
3266         } else {
3267           // If we have any FPRs remaining, we may also have GPRs remaining.
3268           // Args passed in FPRs consume either 1 (f32) or 2 (f64) available
3269           // GPRs.
3270           if (GPR_idx != NumGPRs)
3271             ++GPR_idx;
3272           if (GPR_idx != NumGPRs && Arg.getValueType() == MVT::f64 &&
3273               !isPPC64)  // PPC64 has 64-bit GPR's obviously :)
3274             ++GPR_idx;
3275         }
3276       } else {
3277         LowerMemOpCallTo(DAG, MF, Chain, Arg, PtrOff, SPDiff, ArgOffset,
3278                          isPPC64, isTailCall, false, MemOpChains,
3279                          TailCallArguments, dl);
3280       }
3281       if (isPPC64)
3282         ArgOffset += 8;
3283       else
3284         ArgOffset += Arg.getValueType() == MVT::f32 ? 4 : 8;
3285       break;
3286     case MVT::v4f32:
3287     case MVT::v4i32:
3288     case MVT::v8i16:
3289     case MVT::v16i8:
3290       if (isVarArg) {
3291         // These go aligned on the stack, or in the corresponding R registers
3292         // when within range.  The Darwin PPC ABI doc claims they also go in
3293         // V registers; in fact gcc does this only for arguments that are
3294         // prototyped, not for those that match the ...  We do it for all
3295         // arguments, seems to work.
3296         while (ArgOffset % 16 !=0) {
3297           ArgOffset += PtrByteSize;
3298           if (GPR_idx != NumGPRs)
3299             GPR_idx++;
3300         }
3301         // We could elide this store in the case where the object fits
3302         // entirely in R registers.  Maybe later.
3303         PtrOff = DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr,
3304                             DAG.getConstant(ArgOffset, PtrVT));
3305         SDValue Store = DAG.getStore(Chain, dl, Arg, PtrOff,
3306                                      MachinePointerInfo(), false, false, 0);
3307         MemOpChains.push_back(Store);
3308         if (VR_idx != NumVRs) {
3309           SDValue Load = DAG.getLoad(MVT::v4f32, dl, Store, PtrOff,
3310                                      MachinePointerInfo(),
3311                                      false, false, 0);
3312           MemOpChains.push_back(Load.getValue(1));
3313           RegsToPass.push_back(std::make_pair(VR[VR_idx++], Load));
3314         }
3315         ArgOffset += 16;
3316         for (unsigned i=0; i<16; i+=PtrByteSize) {
3317           if (GPR_idx == NumGPRs)
3318             break;
3319           SDValue Ix = DAG.getNode(ISD::ADD, dl, PtrVT, PtrOff,
3320                                   DAG.getConstant(i, PtrVT));
3321           SDValue Load = DAG.getLoad(PtrVT, dl, Store, Ix, MachinePointerInfo(),
3322                                      false, false, 0);
3323           MemOpChains.push_back(Load.getValue(1));
3324           RegsToPass.push_back(std::make_pair(GPR[GPR_idx++], Load));
3325         }
3326         break;
3327       }
3328 
3329       // Non-varargs Altivec params generally go in registers, but have
3330       // stack space allocated at the end.
3331       if (VR_idx != NumVRs) {
3332         // Doesn't have GPR space allocated.
3333         RegsToPass.push_back(std::make_pair(VR[VR_idx++], Arg));
3334       } else if (nAltivecParamsAtEnd==0) {
3335         // We are emitting Altivec params in order.
3336         LowerMemOpCallTo(DAG, MF, Chain, Arg, PtrOff, SPDiff, ArgOffset,
3337                          isPPC64, isTailCall, true, MemOpChains,
3338                          TailCallArguments, dl);
3339         ArgOffset += 16;
3340       }
3341       break;
3342     }
3343   }
3344   // If all Altivec parameters fit in registers, as they usually do,
3345   // they get stack space following the non-Altivec parameters.  We
3346   // don't track this here because nobody below needs it.
3347   // If there are more Altivec parameters than fit in registers emit
3348   // the stores here.
3349   if (!isVarArg && nAltivecParamsAtEnd > NumVRs) {
3350     unsigned j = 0;
3351     // Offset is aligned; skip 1st 12 params which go in V registers.
3352     ArgOffset = ((ArgOffset+15)/16)*16;
3353     ArgOffset += 12*16;
3354     for (unsigned i = 0; i != NumOps; ++i) {
3355       SDValue Arg = OutVals[i];
3356       EVT ArgType = Outs[i].VT;
3357       if (ArgType==MVT::v4f32 || ArgType==MVT::v4i32 ||
3358           ArgType==MVT::v8i16 || ArgType==MVT::v16i8) {
3359         if (++j > NumVRs) {
3360           SDValue PtrOff;
3361           // We are emitting Altivec params in order.
3362           LowerMemOpCallTo(DAG, MF, Chain, Arg, PtrOff, SPDiff, ArgOffset,
3363                            isPPC64, isTailCall, true, MemOpChains,
3364                            TailCallArguments, dl);
3365           ArgOffset += 16;
3366         }
3367       }
3368     }
3369   }
3370 
3371   if (!MemOpChains.empty())
3372     Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
3373                         &MemOpChains[0], MemOpChains.size());
3374 
3375   // Check if this is an indirect call (MTCTR/BCTRL).
3376   // See PrepareCall() for more information about calls through function
3377   // pointers in the 64-bit SVR4 ABI.
3378   if (!isTailCall && isPPC64 && PPCSubTarget.isSVR4ABI() &&
3379       !dyn_cast<GlobalAddressSDNode>(Callee) &&
3380       !dyn_cast<ExternalSymbolSDNode>(Callee) &&
3381       !isBLACompatibleAddress(Callee, DAG)) {
3382     // Load r2 into a virtual register and store it to the TOC save area.
3383     SDValue Val = DAG.getCopyFromReg(Chain, dl, PPC::X2, MVT::i64);
3384     // TOC save area offset.
3385     SDValue PtrOff = DAG.getIntPtrConstant(40);
3386     SDValue AddPtr = DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr, PtrOff);
3387     Chain = DAG.getStore(Val.getValue(1), dl, Val, AddPtr, MachinePointerInfo(),
3388                          false, false, 0);
3389   }
3390 
3391   // On Darwin, R12 must contain the address of an indirect callee.  This does
3392   // not mean the MTCTR instruction must use R12; it's easier to model this as
3393   // an extra parameter, so do that.
3394   if (!isTailCall &&
3395       !dyn_cast<GlobalAddressSDNode>(Callee) &&
3396       !dyn_cast<ExternalSymbolSDNode>(Callee) &&
3397       !isBLACompatibleAddress(Callee, DAG))
3398     RegsToPass.push_back(std::make_pair((unsigned)(isPPC64 ? PPC::X12 :
3399                                                    PPC::R12), Callee));
3400 
3401   // Build a sequence of copy-to-reg nodes chained together with token chain
3402   // and flag operands which copy the outgoing args into the appropriate regs.
3403   SDValue InFlag;
3404   for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
3405     Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
3406                              RegsToPass[i].second, InFlag);
3407     InFlag = Chain.getValue(1);
3408   }
3409 
3410   if (isTailCall)
3411     PrepareTailCall(DAG, InFlag, Chain, dl, isPPC64, SPDiff, NumBytes, LROp,
3412                     FPOp, true, TailCallArguments);
3413 
3414   return FinishCall(CallConv, dl, isTailCall, isVarArg, DAG,
3415                     RegsToPass, InFlag, Chain, Callee, SPDiff, NumBytes,
3416                     Ins, InVals);
3417 }
3418 
3419 bool
CanLowerReturn(CallingConv::ID CallConv,MachineFunction & MF,bool isVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,LLVMContext & Context) const3420 PPCTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
3421                                   MachineFunction &MF, bool isVarArg,
3422                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
3423                                   LLVMContext &Context) const {
3424   SmallVector<CCValAssign, 16> RVLocs;
3425   CCState CCInfo(CallConv, isVarArg, MF, getTargetMachine(),
3426                  RVLocs, Context);
3427   return CCInfo.CheckReturn(Outs, RetCC_PPC);
3428 }
3429 
3430 SDValue
LowerReturn(SDValue Chain,CallingConv::ID CallConv,bool isVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,DebugLoc dl,SelectionDAG & DAG) const3431 PPCTargetLowering::LowerReturn(SDValue Chain,
3432                                CallingConv::ID CallConv, bool isVarArg,
3433                                const SmallVectorImpl<ISD::OutputArg> &Outs,
3434                                const SmallVectorImpl<SDValue> &OutVals,
3435                                DebugLoc dl, SelectionDAG &DAG) const {
3436 
3437   SmallVector<CCValAssign, 16> RVLocs;
3438   CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
3439 		 getTargetMachine(), RVLocs, *DAG.getContext());
3440   CCInfo.AnalyzeReturn(Outs, RetCC_PPC);
3441 
3442   // If this is the first return lowered for this function, add the regs to the
3443   // liveout set for the function.
3444   if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
3445     for (unsigned i = 0; i != RVLocs.size(); ++i)
3446       DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
3447   }
3448 
3449   SDValue Flag;
3450 
3451   // Copy the result values into the output registers.
3452   for (unsigned i = 0; i != RVLocs.size(); ++i) {
3453     CCValAssign &VA = RVLocs[i];
3454     assert(VA.isRegLoc() && "Can only return in registers!");
3455     Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(),
3456                              OutVals[i], Flag);
3457     Flag = Chain.getValue(1);
3458   }
3459 
3460   if (Flag.getNode())
3461     return DAG.getNode(PPCISD::RET_FLAG, dl, MVT::Other, Chain, Flag);
3462   else
3463     return DAG.getNode(PPCISD::RET_FLAG, dl, MVT::Other, Chain);
3464 }
3465 
LowerSTACKRESTORE(SDValue Op,SelectionDAG & DAG,const PPCSubtarget & Subtarget) const3466 SDValue PPCTargetLowering::LowerSTACKRESTORE(SDValue Op, SelectionDAG &DAG,
3467                                    const PPCSubtarget &Subtarget) const {
3468   // When we pop the dynamic allocation we need to restore the SP link.
3469   DebugLoc dl = Op.getDebugLoc();
3470 
3471   // Get the corect type for pointers.
3472   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3473 
3474   // Construct the stack pointer operand.
3475   bool isPPC64 = Subtarget.isPPC64();
3476   unsigned SP = isPPC64 ? PPC::X1 : PPC::R1;
3477   SDValue StackPtr = DAG.getRegister(SP, PtrVT);
3478 
3479   // Get the operands for the STACKRESTORE.
3480   SDValue Chain = Op.getOperand(0);
3481   SDValue SaveSP = Op.getOperand(1);
3482 
3483   // Load the old link SP.
3484   SDValue LoadLinkSP = DAG.getLoad(PtrVT, dl, Chain, StackPtr,
3485                                    MachinePointerInfo(),
3486                                    false, false, 0);
3487 
3488   // Restore the stack pointer.
3489   Chain = DAG.getCopyToReg(LoadLinkSP.getValue(1), dl, SP, SaveSP);
3490 
3491   // Store the old link SP.
3492   return DAG.getStore(Chain, dl, LoadLinkSP, StackPtr, MachinePointerInfo(),
3493                       false, false, 0);
3494 }
3495 
3496 
3497 
3498 SDValue
getReturnAddrFrameIndex(SelectionDAG & DAG) const3499 PPCTargetLowering::getReturnAddrFrameIndex(SelectionDAG & DAG) const {
3500   MachineFunction &MF = DAG.getMachineFunction();
3501   bool isPPC64 = PPCSubTarget.isPPC64();
3502   bool isDarwinABI = PPCSubTarget.isDarwinABI();
3503   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3504 
3505   // Get current frame pointer save index.  The users of this index will be
3506   // primarily DYNALLOC instructions.
3507   PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
3508   int RASI = FI->getReturnAddrSaveIndex();
3509 
3510   // If the frame pointer save index hasn't been defined yet.
3511   if (!RASI) {
3512     // Find out what the fix offset of the frame pointer save area.
3513     int LROffset = PPCFrameLowering::getReturnSaveOffset(isPPC64, isDarwinABI);
3514     // Allocate the frame index for frame pointer save area.
3515     RASI = MF.getFrameInfo()->CreateFixedObject(isPPC64? 8 : 4, LROffset, true);
3516     // Save the result.
3517     FI->setReturnAddrSaveIndex(RASI);
3518   }
3519   return DAG.getFrameIndex(RASI, PtrVT);
3520 }
3521 
3522 SDValue
getFramePointerFrameIndex(SelectionDAG & DAG) const3523 PPCTargetLowering::getFramePointerFrameIndex(SelectionDAG & DAG) const {
3524   MachineFunction &MF = DAG.getMachineFunction();
3525   bool isPPC64 = PPCSubTarget.isPPC64();
3526   bool isDarwinABI = PPCSubTarget.isDarwinABI();
3527   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3528 
3529   // Get current frame pointer save index.  The users of this index will be
3530   // primarily DYNALLOC instructions.
3531   PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
3532   int FPSI = FI->getFramePointerSaveIndex();
3533 
3534   // If the frame pointer save index hasn't been defined yet.
3535   if (!FPSI) {
3536     // Find out what the fix offset of the frame pointer save area.
3537     int FPOffset = PPCFrameLowering::getFramePointerSaveOffset(isPPC64,
3538                                                            isDarwinABI);
3539 
3540     // Allocate the frame index for frame pointer save area.
3541     FPSI = MF.getFrameInfo()->CreateFixedObject(isPPC64? 8 : 4, FPOffset, true);
3542     // Save the result.
3543     FI->setFramePointerSaveIndex(FPSI);
3544   }
3545   return DAG.getFrameIndex(FPSI, PtrVT);
3546 }
3547 
LowerDYNAMIC_STACKALLOC(SDValue Op,SelectionDAG & DAG,const PPCSubtarget & Subtarget) const3548 SDValue PPCTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
3549                                          SelectionDAG &DAG,
3550                                          const PPCSubtarget &Subtarget) const {
3551   // Get the inputs.
3552   SDValue Chain = Op.getOperand(0);
3553   SDValue Size  = Op.getOperand(1);
3554   DebugLoc dl = Op.getDebugLoc();
3555 
3556   // Get the corect type for pointers.
3557   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3558   // Negate the size.
3559   SDValue NegSize = DAG.getNode(ISD::SUB, dl, PtrVT,
3560                                   DAG.getConstant(0, PtrVT), Size);
3561   // Construct a node for the frame pointer save index.
3562   SDValue FPSIdx = getFramePointerFrameIndex(DAG);
3563   // Build a DYNALLOC node.
3564   SDValue Ops[3] = { Chain, NegSize, FPSIdx };
3565   SDVTList VTs = DAG.getVTList(PtrVT, MVT::Other);
3566   return DAG.getNode(PPCISD::DYNALLOC, dl, VTs, Ops, 3);
3567 }
3568 
3569 /// LowerSELECT_CC - Lower floating point select_cc's into fsel instruction when
3570 /// possible.
LowerSELECT_CC(SDValue Op,SelectionDAG & DAG) const3571 SDValue PPCTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
3572   // Not FP? Not a fsel.
3573   if (!Op.getOperand(0).getValueType().isFloatingPoint() ||
3574       !Op.getOperand(2).getValueType().isFloatingPoint())
3575     return Op;
3576 
3577   ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
3578 
3579   // Cannot handle SETEQ/SETNE.
3580   if (CC == ISD::SETEQ || CC == ISD::SETNE) return Op;
3581 
3582   EVT ResVT = Op.getValueType();
3583   EVT CmpVT = Op.getOperand(0).getValueType();
3584   SDValue LHS = Op.getOperand(0), RHS = Op.getOperand(1);
3585   SDValue TV  = Op.getOperand(2), FV  = Op.getOperand(3);
3586   DebugLoc dl = Op.getDebugLoc();
3587 
3588   // If the RHS of the comparison is a 0.0, we don't need to do the
3589   // subtraction at all.
3590   if (isFloatingPointZero(RHS))
3591     switch (CC) {
3592     default: break;       // SETUO etc aren't handled by fsel.
3593     case ISD::SETULT:
3594     case ISD::SETLT:
3595       std::swap(TV, FV);  // fsel is natively setge, swap operands for setlt
3596     case ISD::SETOGE:
3597     case ISD::SETGE:
3598       if (LHS.getValueType() == MVT::f32)   // Comparison is always 64-bits
3599         LHS = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, LHS);
3600       return DAG.getNode(PPCISD::FSEL, dl, ResVT, LHS, TV, FV);
3601     case ISD::SETUGT:
3602     case ISD::SETGT:
3603       std::swap(TV, FV);  // fsel is natively setge, swap operands for setlt
3604     case ISD::SETOLE:
3605     case ISD::SETLE:
3606       if (LHS.getValueType() == MVT::f32)   // Comparison is always 64-bits
3607         LHS = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, LHS);
3608       return DAG.getNode(PPCISD::FSEL, dl, ResVT,
3609                          DAG.getNode(ISD::FNEG, dl, MVT::f64, LHS), TV, FV);
3610     }
3611 
3612   SDValue Cmp;
3613   switch (CC) {
3614   default: break;       // SETUO etc aren't handled by fsel.
3615   case ISD::SETULT:
3616   case ISD::SETLT:
3617     Cmp = DAG.getNode(ISD::FSUB, dl, CmpVT, LHS, RHS);
3618     if (Cmp.getValueType() == MVT::f32)   // Comparison is always 64-bits
3619       Cmp = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Cmp);
3620       return DAG.getNode(PPCISD::FSEL, dl, ResVT, Cmp, FV, TV);
3621   case ISD::SETOGE:
3622   case ISD::SETGE:
3623     Cmp = DAG.getNode(ISD::FSUB, dl, CmpVT, LHS, RHS);
3624     if (Cmp.getValueType() == MVT::f32)   // Comparison is always 64-bits
3625       Cmp = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Cmp);
3626       return DAG.getNode(PPCISD::FSEL, dl, ResVT, Cmp, TV, FV);
3627   case ISD::SETUGT:
3628   case ISD::SETGT:
3629     Cmp = DAG.getNode(ISD::FSUB, dl, CmpVT, RHS, LHS);
3630     if (Cmp.getValueType() == MVT::f32)   // Comparison is always 64-bits
3631       Cmp = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Cmp);
3632       return DAG.getNode(PPCISD::FSEL, dl, ResVT, Cmp, FV, TV);
3633   case ISD::SETOLE:
3634   case ISD::SETLE:
3635     Cmp = DAG.getNode(ISD::FSUB, dl, CmpVT, RHS, LHS);
3636     if (Cmp.getValueType() == MVT::f32)   // Comparison is always 64-bits
3637       Cmp = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Cmp);
3638       return DAG.getNode(PPCISD::FSEL, dl, ResVT, Cmp, TV, FV);
3639   }
3640   return Op;
3641 }
3642 
3643 // FIXME: Split this code up when LegalizeDAGTypes lands.
LowerFP_TO_INT(SDValue Op,SelectionDAG & DAG,DebugLoc dl) const3644 SDValue PPCTargetLowering::LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG,
3645                                            DebugLoc dl) const {
3646   assert(Op.getOperand(0).getValueType().isFloatingPoint());
3647   SDValue Src = Op.getOperand(0);
3648   if (Src.getValueType() == MVT::f32)
3649     Src = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Src);
3650 
3651   SDValue Tmp;
3652   switch (Op.getValueType().getSimpleVT().SimpleTy) {
3653   default: llvm_unreachable("Unhandled FP_TO_INT type in custom expander!");
3654   case MVT::i32:
3655     Tmp = DAG.getNode(Op.getOpcode()==ISD::FP_TO_SINT ? PPCISD::FCTIWZ :
3656                                                          PPCISD::FCTIDZ,
3657                       dl, MVT::f64, Src);
3658     break;
3659   case MVT::i64:
3660     Tmp = DAG.getNode(PPCISD::FCTIDZ, dl, MVT::f64, Src);
3661     break;
3662   }
3663 
3664   // Convert the FP value to an int value through memory.
3665   SDValue FIPtr = DAG.CreateStackTemporary(MVT::f64);
3666 
3667   // Emit a store to the stack slot.
3668   SDValue Chain = DAG.getStore(DAG.getEntryNode(), dl, Tmp, FIPtr,
3669                                MachinePointerInfo(), false, false, 0);
3670 
3671   // Result is a load from the stack slot.  If loading 4 bytes, make sure to
3672   // add in a bias.
3673   if (Op.getValueType() == MVT::i32)
3674     FIPtr = DAG.getNode(ISD::ADD, dl, FIPtr.getValueType(), FIPtr,
3675                         DAG.getConstant(4, FIPtr.getValueType()));
3676   return DAG.getLoad(Op.getValueType(), dl, Chain, FIPtr, MachinePointerInfo(),
3677                      false, false, 0);
3678 }
3679 
LowerSINT_TO_FP(SDValue Op,SelectionDAG & DAG) const3680 SDValue PPCTargetLowering::LowerSINT_TO_FP(SDValue Op,
3681                                            SelectionDAG &DAG) const {
3682   DebugLoc dl = Op.getDebugLoc();
3683   // Don't handle ppc_fp128 here; let it be lowered to a libcall.
3684   if (Op.getValueType() != MVT::f32 && Op.getValueType() != MVT::f64)
3685     return SDValue();
3686 
3687   if (Op.getOperand(0).getValueType() == MVT::i64) {
3688     SDValue Bits = DAG.getNode(ISD::BITCAST, dl, MVT::f64, Op.getOperand(0));
3689     SDValue FP = DAG.getNode(PPCISD::FCFID, dl, MVT::f64, Bits);
3690     if (Op.getValueType() == MVT::f32)
3691       FP = DAG.getNode(ISD::FP_ROUND, dl,
3692                        MVT::f32, FP, DAG.getIntPtrConstant(0));
3693     return FP;
3694   }
3695 
3696   assert(Op.getOperand(0).getValueType() == MVT::i32 &&
3697          "Unhandled SINT_TO_FP type in custom expander!");
3698   // Since we only generate this in 64-bit mode, we can take advantage of
3699   // 64-bit registers.  In particular, sign extend the input value into the
3700   // 64-bit register with extsw, store the WHOLE 64-bit value into the stack
3701   // then lfd it and fcfid it.
3702   MachineFunction &MF = DAG.getMachineFunction();
3703   MachineFrameInfo *FrameInfo = MF.getFrameInfo();
3704   int FrameIdx = FrameInfo->CreateStackObject(8, 8, false);
3705   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3706   SDValue FIdx = DAG.getFrameIndex(FrameIdx, PtrVT);
3707 
3708   SDValue Ext64 = DAG.getNode(PPCISD::EXTSW_32, dl, MVT::i32,
3709                                 Op.getOperand(0));
3710 
3711   // STD the extended value into the stack slot.
3712   MachineMemOperand *MMO =
3713     MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(FrameIdx),
3714                             MachineMemOperand::MOStore, 8, 8);
3715   SDValue Ops[] = { DAG.getEntryNode(), Ext64, FIdx };
3716   SDValue Store =
3717     DAG.getMemIntrinsicNode(PPCISD::STD_32, dl, DAG.getVTList(MVT::Other),
3718                             Ops, 4, MVT::i64, MMO);
3719   // Load the value as a double.
3720   SDValue Ld = DAG.getLoad(MVT::f64, dl, Store, FIdx, MachinePointerInfo(),
3721                            false, false, 0);
3722 
3723   // FCFID it and return it.
3724   SDValue FP = DAG.getNode(PPCISD::FCFID, dl, MVT::f64, Ld);
3725   if (Op.getValueType() == MVT::f32)
3726     FP = DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, FP, DAG.getIntPtrConstant(0));
3727   return FP;
3728 }
3729 
LowerFLT_ROUNDS_(SDValue Op,SelectionDAG & DAG) const3730 SDValue PPCTargetLowering::LowerFLT_ROUNDS_(SDValue Op,
3731                                             SelectionDAG &DAG) const {
3732   DebugLoc dl = Op.getDebugLoc();
3733   /*
3734    The rounding mode is in bits 30:31 of FPSR, and has the following
3735    settings:
3736      00 Round to nearest
3737      01 Round to 0
3738      10 Round to +inf
3739      11 Round to -inf
3740 
3741   FLT_ROUNDS, on the other hand, expects the following:
3742     -1 Undefined
3743      0 Round to 0
3744      1 Round to nearest
3745      2 Round to +inf
3746      3 Round to -inf
3747 
3748   To perform the conversion, we do:
3749     ((FPSCR & 0x3) ^ ((~FPSCR & 0x3) >> 1))
3750   */
3751 
3752   MachineFunction &MF = DAG.getMachineFunction();
3753   EVT VT = Op.getValueType();
3754   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
3755   std::vector<EVT> NodeTys;
3756   SDValue MFFSreg, InFlag;
3757 
3758   // Save FP Control Word to register
3759   NodeTys.push_back(MVT::f64);    // return register
3760   NodeTys.push_back(MVT::Glue);   // unused in this context
3761   SDValue Chain = DAG.getNode(PPCISD::MFFS, dl, NodeTys, &InFlag, 0);
3762 
3763   // Save FP register to stack slot
3764   int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8, false);
3765   SDValue StackSlot = DAG.getFrameIndex(SSFI, PtrVT);
3766   SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, Chain,
3767                                StackSlot, MachinePointerInfo(), false, false,0);
3768 
3769   // Load FP Control Word from low 32 bits of stack slot.
3770   SDValue Four = DAG.getConstant(4, PtrVT);
3771   SDValue Addr = DAG.getNode(ISD::ADD, dl, PtrVT, StackSlot, Four);
3772   SDValue CWD = DAG.getLoad(MVT::i32, dl, Store, Addr, MachinePointerInfo(),
3773                             false, false, 0);
3774 
3775   // Transform as necessary
3776   SDValue CWD1 =
3777     DAG.getNode(ISD::AND, dl, MVT::i32,
3778                 CWD, DAG.getConstant(3, MVT::i32));
3779   SDValue CWD2 =
3780     DAG.getNode(ISD::SRL, dl, MVT::i32,
3781                 DAG.getNode(ISD::AND, dl, MVT::i32,
3782                             DAG.getNode(ISD::XOR, dl, MVT::i32,
3783                                         CWD, DAG.getConstant(3, MVT::i32)),
3784                             DAG.getConstant(3, MVT::i32)),
3785                 DAG.getConstant(1, MVT::i32));
3786 
3787   SDValue RetVal =
3788     DAG.getNode(ISD::XOR, dl, MVT::i32, CWD1, CWD2);
3789 
3790   return DAG.getNode((VT.getSizeInBits() < 16 ?
3791                       ISD::TRUNCATE : ISD::ZERO_EXTEND), dl, VT, RetVal);
3792 }
3793 
LowerSHL_PARTS(SDValue Op,SelectionDAG & DAG) const3794 SDValue PPCTargetLowering::LowerSHL_PARTS(SDValue Op, SelectionDAG &DAG) const {
3795   EVT VT = Op.getValueType();
3796   unsigned BitWidth = VT.getSizeInBits();
3797   DebugLoc dl = Op.getDebugLoc();
3798   assert(Op.getNumOperands() == 3 &&
3799          VT == Op.getOperand(1).getValueType() &&
3800          "Unexpected SHL!");
3801 
3802   // Expand into a bunch of logical ops.  Note that these ops
3803   // depend on the PPC behavior for oversized shift amounts.
3804   SDValue Lo = Op.getOperand(0);
3805   SDValue Hi = Op.getOperand(1);
3806   SDValue Amt = Op.getOperand(2);
3807   EVT AmtVT = Amt.getValueType();
3808 
3809   SDValue Tmp1 = DAG.getNode(ISD::SUB, dl, AmtVT,
3810                              DAG.getConstant(BitWidth, AmtVT), Amt);
3811   SDValue Tmp2 = DAG.getNode(PPCISD::SHL, dl, VT, Hi, Amt);
3812   SDValue Tmp3 = DAG.getNode(PPCISD::SRL, dl, VT, Lo, Tmp1);
3813   SDValue Tmp4 = DAG.getNode(ISD::OR , dl, VT, Tmp2, Tmp3);
3814   SDValue Tmp5 = DAG.getNode(ISD::ADD, dl, AmtVT, Amt,
3815                              DAG.getConstant(-BitWidth, AmtVT));
3816   SDValue Tmp6 = DAG.getNode(PPCISD::SHL, dl, VT, Lo, Tmp5);
3817   SDValue OutHi = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp6);
3818   SDValue OutLo = DAG.getNode(PPCISD::SHL, dl, VT, Lo, Amt);
3819   SDValue OutOps[] = { OutLo, OutHi };
3820   return DAG.getMergeValues(OutOps, 2, dl);
3821 }
3822 
LowerSRL_PARTS(SDValue Op,SelectionDAG & DAG) const3823 SDValue PPCTargetLowering::LowerSRL_PARTS(SDValue Op, SelectionDAG &DAG) const {
3824   EVT VT = Op.getValueType();
3825   DebugLoc dl = Op.getDebugLoc();
3826   unsigned BitWidth = VT.getSizeInBits();
3827   assert(Op.getNumOperands() == 3 &&
3828          VT == Op.getOperand(1).getValueType() &&
3829          "Unexpected SRL!");
3830 
3831   // Expand into a bunch of logical ops.  Note that these ops
3832   // depend on the PPC behavior for oversized shift amounts.
3833   SDValue Lo = Op.getOperand(0);
3834   SDValue Hi = Op.getOperand(1);
3835   SDValue Amt = Op.getOperand(2);
3836   EVT AmtVT = Amt.getValueType();
3837 
3838   SDValue Tmp1 = DAG.getNode(ISD::SUB, dl, AmtVT,
3839                              DAG.getConstant(BitWidth, AmtVT), Amt);
3840   SDValue Tmp2 = DAG.getNode(PPCISD::SRL, dl, VT, Lo, Amt);
3841   SDValue Tmp3 = DAG.getNode(PPCISD::SHL, dl, VT, Hi, Tmp1);
3842   SDValue Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp3);
3843   SDValue Tmp5 = DAG.getNode(ISD::ADD, dl, AmtVT, Amt,
3844                              DAG.getConstant(-BitWidth, AmtVT));
3845   SDValue Tmp6 = DAG.getNode(PPCISD::SRL, dl, VT, Hi, Tmp5);
3846   SDValue OutLo = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp6);
3847   SDValue OutHi = DAG.getNode(PPCISD::SRL, dl, VT, Hi, Amt);
3848   SDValue OutOps[] = { OutLo, OutHi };
3849   return DAG.getMergeValues(OutOps, 2, dl);
3850 }
3851 
LowerSRA_PARTS(SDValue Op,SelectionDAG & DAG) const3852 SDValue PPCTargetLowering::LowerSRA_PARTS(SDValue Op, SelectionDAG &DAG) const {
3853   DebugLoc dl = Op.getDebugLoc();
3854   EVT VT = Op.getValueType();
3855   unsigned BitWidth = VT.getSizeInBits();
3856   assert(Op.getNumOperands() == 3 &&
3857          VT == Op.getOperand(1).getValueType() &&
3858          "Unexpected SRA!");
3859 
3860   // Expand into a bunch of logical ops, followed by a select_cc.
3861   SDValue Lo = Op.getOperand(0);
3862   SDValue Hi = Op.getOperand(1);
3863   SDValue Amt = Op.getOperand(2);
3864   EVT AmtVT = Amt.getValueType();
3865 
3866   SDValue Tmp1 = DAG.getNode(ISD::SUB, dl, AmtVT,
3867                              DAG.getConstant(BitWidth, AmtVT), Amt);
3868   SDValue Tmp2 = DAG.getNode(PPCISD::SRL, dl, VT, Lo, Amt);
3869   SDValue Tmp3 = DAG.getNode(PPCISD::SHL, dl, VT, Hi, Tmp1);
3870   SDValue Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp3);
3871   SDValue Tmp5 = DAG.getNode(ISD::ADD, dl, AmtVT, Amt,
3872                              DAG.getConstant(-BitWidth, AmtVT));
3873   SDValue Tmp6 = DAG.getNode(PPCISD::SRA, dl, VT, Hi, Tmp5);
3874   SDValue OutHi = DAG.getNode(PPCISD::SRA, dl, VT, Hi, Amt);
3875   SDValue OutLo = DAG.getSelectCC(dl, Tmp5, DAG.getConstant(0, AmtVT),
3876                                   Tmp4, Tmp6, ISD::SETLE);
3877   SDValue OutOps[] = { OutLo, OutHi };
3878   return DAG.getMergeValues(OutOps, 2, dl);
3879 }
3880 
3881 //===----------------------------------------------------------------------===//
3882 // Vector related lowering.
3883 //
3884 
3885 /// BuildSplatI - Build a canonical splati of Val with an element size of
3886 /// SplatSize.  Cast the result to VT.
BuildSplatI(int Val,unsigned SplatSize,EVT VT,SelectionDAG & DAG,DebugLoc dl)3887 static SDValue BuildSplatI(int Val, unsigned SplatSize, EVT VT,
3888                              SelectionDAG &DAG, DebugLoc dl) {
3889   assert(Val >= -16 && Val <= 15 && "vsplti is out of range!");
3890 
3891   static const EVT VTys[] = { // canonical VT to use for each size.
3892     MVT::v16i8, MVT::v8i16, MVT::Other, MVT::v4i32
3893   };
3894 
3895   EVT ReqVT = VT != MVT::Other ? VT : VTys[SplatSize-1];
3896 
3897   // Force vspltis[hw] -1 to vspltisb -1 to canonicalize.
3898   if (Val == -1)
3899     SplatSize = 1;
3900 
3901   EVT CanonicalVT = VTys[SplatSize-1];
3902 
3903   // Build a canonical splat for this value.
3904   SDValue Elt = DAG.getConstant(Val, MVT::i32);
3905   SmallVector<SDValue, 8> Ops;
3906   Ops.assign(CanonicalVT.getVectorNumElements(), Elt);
3907   SDValue Res = DAG.getNode(ISD::BUILD_VECTOR, dl, CanonicalVT,
3908                               &Ops[0], Ops.size());
3909   return DAG.getNode(ISD::BITCAST, dl, ReqVT, Res);
3910 }
3911 
3912 /// BuildIntrinsicOp - Return a binary operator intrinsic node with the
3913 /// specified intrinsic ID.
BuildIntrinsicOp(unsigned IID,SDValue LHS,SDValue RHS,SelectionDAG & DAG,DebugLoc dl,EVT DestVT=MVT::Other)3914 static SDValue BuildIntrinsicOp(unsigned IID, SDValue LHS, SDValue RHS,
3915                                 SelectionDAG &DAG, DebugLoc dl,
3916                                 EVT DestVT = MVT::Other) {
3917   if (DestVT == MVT::Other) DestVT = LHS.getValueType();
3918   return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, DestVT,
3919                      DAG.getConstant(IID, MVT::i32), LHS, RHS);
3920 }
3921 
3922 /// BuildIntrinsicOp - Return a ternary operator intrinsic node with the
3923 /// specified intrinsic ID.
BuildIntrinsicOp(unsigned IID,SDValue Op0,SDValue Op1,SDValue Op2,SelectionDAG & DAG,DebugLoc dl,EVT DestVT=MVT::Other)3924 static SDValue BuildIntrinsicOp(unsigned IID, SDValue Op0, SDValue Op1,
3925                                 SDValue Op2, SelectionDAG &DAG,
3926                                 DebugLoc dl, EVT DestVT = MVT::Other) {
3927   if (DestVT == MVT::Other) DestVT = Op0.getValueType();
3928   return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, DestVT,
3929                      DAG.getConstant(IID, MVT::i32), Op0, Op1, Op2);
3930 }
3931 
3932 
3933 /// BuildVSLDOI - Return a VECTOR_SHUFFLE that is a vsldoi of the specified
3934 /// amount.  The result has the specified value type.
BuildVSLDOI(SDValue LHS,SDValue RHS,unsigned Amt,EVT VT,SelectionDAG & DAG,DebugLoc dl)3935 static SDValue BuildVSLDOI(SDValue LHS, SDValue RHS, unsigned Amt,
3936                              EVT VT, SelectionDAG &DAG, DebugLoc dl) {
3937   // Force LHS/RHS to be the right type.
3938   LHS = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, LHS);
3939   RHS = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, RHS);
3940 
3941   int Ops[16];
3942   for (unsigned i = 0; i != 16; ++i)
3943     Ops[i] = i + Amt;
3944   SDValue T = DAG.getVectorShuffle(MVT::v16i8, dl, LHS, RHS, Ops);
3945   return DAG.getNode(ISD::BITCAST, dl, VT, T);
3946 }
3947 
3948 // If this is a case we can't handle, return null and let the default
3949 // expansion code take care of it.  If we CAN select this case, and if it
3950 // selects to a single instruction, return Op.  Otherwise, if we can codegen
3951 // this case more efficiently than a constant pool load, lower it to the
3952 // sequence of ops that should be used.
LowerBUILD_VECTOR(SDValue Op,SelectionDAG & DAG) const3953 SDValue PPCTargetLowering::LowerBUILD_VECTOR(SDValue Op,
3954                                              SelectionDAG &DAG) const {
3955   DebugLoc dl = Op.getDebugLoc();
3956   BuildVectorSDNode *BVN = dyn_cast<BuildVectorSDNode>(Op.getNode());
3957   assert(BVN != 0 && "Expected a BuildVectorSDNode in LowerBUILD_VECTOR");
3958 
3959   // Check if this is a splat of a constant value.
3960   APInt APSplatBits, APSplatUndef;
3961   unsigned SplatBitSize;
3962   bool HasAnyUndefs;
3963   if (! BVN->isConstantSplat(APSplatBits, APSplatUndef, SplatBitSize,
3964                              HasAnyUndefs, 0, true) || SplatBitSize > 32)
3965     return SDValue();
3966 
3967   unsigned SplatBits = APSplatBits.getZExtValue();
3968   unsigned SplatUndef = APSplatUndef.getZExtValue();
3969   unsigned SplatSize = SplatBitSize / 8;
3970 
3971   // First, handle single instruction cases.
3972 
3973   // All zeros?
3974   if (SplatBits == 0) {
3975     // Canonicalize all zero vectors to be v4i32.
3976     if (Op.getValueType() != MVT::v4i32 || HasAnyUndefs) {
3977       SDValue Z = DAG.getConstant(0, MVT::i32);
3978       Z = DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32, Z, Z, Z, Z);
3979       Op = DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Z);
3980     }
3981     return Op;
3982   }
3983 
3984   // If the sign extended value is in the range [-16,15], use VSPLTI[bhw].
3985   int32_t SextVal= (int32_t(SplatBits << (32-SplatBitSize)) >>
3986                     (32-SplatBitSize));
3987   if (SextVal >= -16 && SextVal <= 15)
3988     return BuildSplatI(SextVal, SplatSize, Op.getValueType(), DAG, dl);
3989 
3990 
3991   // Two instruction sequences.
3992 
3993   // If this value is in the range [-32,30] and is even, use:
3994   //    tmp = VSPLTI[bhw], result = add tmp, tmp
3995   if (SextVal >= -32 && SextVal <= 30 && (SextVal & 1) == 0) {
3996     SDValue Res = BuildSplatI(SextVal >> 1, SplatSize, MVT::Other, DAG, dl);
3997     Res = DAG.getNode(ISD::ADD, dl, Res.getValueType(), Res, Res);
3998     return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
3999   }
4000 
4001   // If this is 0x8000_0000 x 4, turn into vspltisw + vslw.  If it is
4002   // 0x7FFF_FFFF x 4, turn it into not(0x8000_0000).  This is important
4003   // for fneg/fabs.
4004   if (SplatSize == 4 && SplatBits == (0x7FFFFFFF&~SplatUndef)) {
4005     // Make -1 and vspltisw -1:
4006     SDValue OnesV = BuildSplatI(-1, 4, MVT::v4i32, DAG, dl);
4007 
4008     // Make the VSLW intrinsic, computing 0x8000_0000.
4009     SDValue Res = BuildIntrinsicOp(Intrinsic::ppc_altivec_vslw, OnesV,
4010                                    OnesV, DAG, dl);
4011 
4012     // xor by OnesV to invert it.
4013     Res = DAG.getNode(ISD::XOR, dl, MVT::v4i32, Res, OnesV);
4014     return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
4015   }
4016 
4017   // Check to see if this is a wide variety of vsplti*, binop self cases.
4018   static const signed char SplatCsts[] = {
4019     -1, 1, -2, 2, -3, 3, -4, 4, -5, 5, -6, 6, -7, 7,
4020     -8, 8, -9, 9, -10, 10, -11, 11, -12, 12, -13, 13, 14, -14, 15, -15, -16
4021   };
4022 
4023   for (unsigned idx = 0; idx < array_lengthof(SplatCsts); ++idx) {
4024     // Indirect through the SplatCsts array so that we favor 'vsplti -1' for
4025     // cases which are ambiguous (e.g. formation of 0x8000_0000).  'vsplti -1'
4026     int i = SplatCsts[idx];
4027 
4028     // Figure out what shift amount will be used by altivec if shifted by i in
4029     // this splat size.
4030     unsigned TypeShiftAmt = i & (SplatBitSize-1);
4031 
4032     // vsplti + shl self.
4033     if (SextVal == (i << (int)TypeShiftAmt)) {
4034       SDValue Res = BuildSplatI(i, SplatSize, MVT::Other, DAG, dl);
4035       static const unsigned IIDs[] = { // Intrinsic to use for each size.
4036         Intrinsic::ppc_altivec_vslb, Intrinsic::ppc_altivec_vslh, 0,
4037         Intrinsic::ppc_altivec_vslw
4038       };
4039       Res = BuildIntrinsicOp(IIDs[SplatSize-1], Res, Res, DAG, dl);
4040       return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
4041     }
4042 
4043     // vsplti + srl self.
4044     if (SextVal == (int)((unsigned)i >> TypeShiftAmt)) {
4045       SDValue Res = BuildSplatI(i, SplatSize, MVT::Other, DAG, dl);
4046       static const unsigned IIDs[] = { // Intrinsic to use for each size.
4047         Intrinsic::ppc_altivec_vsrb, Intrinsic::ppc_altivec_vsrh, 0,
4048         Intrinsic::ppc_altivec_vsrw
4049       };
4050       Res = BuildIntrinsicOp(IIDs[SplatSize-1], Res, Res, DAG, dl);
4051       return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
4052     }
4053 
4054     // vsplti + sra self.
4055     if (SextVal == (int)((unsigned)i >> TypeShiftAmt)) {
4056       SDValue Res = BuildSplatI(i, SplatSize, MVT::Other, DAG, dl);
4057       static const unsigned IIDs[] = { // Intrinsic to use for each size.
4058         Intrinsic::ppc_altivec_vsrab, Intrinsic::ppc_altivec_vsrah, 0,
4059         Intrinsic::ppc_altivec_vsraw
4060       };
4061       Res = BuildIntrinsicOp(IIDs[SplatSize-1], Res, Res, DAG, dl);
4062       return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
4063     }
4064 
4065     // vsplti + rol self.
4066     if (SextVal == (int)(((unsigned)i << TypeShiftAmt) |
4067                          ((unsigned)i >> (SplatBitSize-TypeShiftAmt)))) {
4068       SDValue Res = BuildSplatI(i, SplatSize, MVT::Other, DAG, dl);
4069       static const unsigned IIDs[] = { // Intrinsic to use for each size.
4070         Intrinsic::ppc_altivec_vrlb, Intrinsic::ppc_altivec_vrlh, 0,
4071         Intrinsic::ppc_altivec_vrlw
4072       };
4073       Res = BuildIntrinsicOp(IIDs[SplatSize-1], Res, Res, DAG, dl);
4074       return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Res);
4075     }
4076 
4077     // t = vsplti c, result = vsldoi t, t, 1
4078     if (SextVal == ((i << 8) | (i < 0 ? 0xFF : 0))) {
4079       SDValue T = BuildSplatI(i, SplatSize, MVT::v16i8, DAG, dl);
4080       return BuildVSLDOI(T, T, 1, Op.getValueType(), DAG, dl);
4081     }
4082     // t = vsplti c, result = vsldoi t, t, 2
4083     if (SextVal == ((i << 16) | (i < 0 ? 0xFFFF : 0))) {
4084       SDValue T = BuildSplatI(i, SplatSize, MVT::v16i8, DAG, dl);
4085       return BuildVSLDOI(T, T, 2, Op.getValueType(), DAG, dl);
4086     }
4087     // t = vsplti c, result = vsldoi t, t, 3
4088     if (SextVal == ((i << 24) | (i < 0 ? 0xFFFFFF : 0))) {
4089       SDValue T = BuildSplatI(i, SplatSize, MVT::v16i8, DAG, dl);
4090       return BuildVSLDOI(T, T, 3, Op.getValueType(), DAG, dl);
4091     }
4092   }
4093 
4094   // Three instruction sequences.
4095 
4096   // Odd, in range [17,31]:  (vsplti C)-(vsplti -16).
4097   if (SextVal >= 0 && SextVal <= 31) {
4098     SDValue LHS = BuildSplatI(SextVal-16, SplatSize, MVT::Other, DAG, dl);
4099     SDValue RHS = BuildSplatI(-16, SplatSize, MVT::Other, DAG, dl);
4100     LHS = DAG.getNode(ISD::SUB, dl, LHS.getValueType(), LHS, RHS);
4101     return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), LHS);
4102   }
4103   // Odd, in range [-31,-17]:  (vsplti C)+(vsplti -16).
4104   if (SextVal >= -31 && SextVal <= 0) {
4105     SDValue LHS = BuildSplatI(SextVal+16, SplatSize, MVT::Other, DAG, dl);
4106     SDValue RHS = BuildSplatI(-16, SplatSize, MVT::Other, DAG, dl);
4107     LHS = DAG.getNode(ISD::ADD, dl, LHS.getValueType(), LHS, RHS);
4108     return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), LHS);
4109   }
4110 
4111   return SDValue();
4112 }
4113 
4114 /// GeneratePerfectShuffle - Given an entry in the perfect-shuffle table, emit
4115 /// the specified operations to build the shuffle.
GeneratePerfectShuffle(unsigned PFEntry,SDValue LHS,SDValue RHS,SelectionDAG & DAG,DebugLoc dl)4116 static SDValue GeneratePerfectShuffle(unsigned PFEntry, SDValue LHS,
4117                                       SDValue RHS, SelectionDAG &DAG,
4118                                       DebugLoc dl) {
4119   unsigned OpNum = (PFEntry >> 26) & 0x0F;
4120   unsigned LHSID = (PFEntry >> 13) & ((1 << 13)-1);
4121   unsigned RHSID = (PFEntry >>  0) & ((1 << 13)-1);
4122 
4123   enum {
4124     OP_COPY = 0,  // Copy, used for things like <u,u,u,3> to say it is <0,1,2,3>
4125     OP_VMRGHW,
4126     OP_VMRGLW,
4127     OP_VSPLTISW0,
4128     OP_VSPLTISW1,
4129     OP_VSPLTISW2,
4130     OP_VSPLTISW3,
4131     OP_VSLDOI4,
4132     OP_VSLDOI8,
4133     OP_VSLDOI12
4134   };
4135 
4136   if (OpNum == OP_COPY) {
4137     if (LHSID == (1*9+2)*9+3) return LHS;
4138     assert(LHSID == ((4*9+5)*9+6)*9+7 && "Illegal OP_COPY!");
4139     return RHS;
4140   }
4141 
4142   SDValue OpLHS, OpRHS;
4143   OpLHS = GeneratePerfectShuffle(PerfectShuffleTable[LHSID], LHS, RHS, DAG, dl);
4144   OpRHS = GeneratePerfectShuffle(PerfectShuffleTable[RHSID], LHS, RHS, DAG, dl);
4145 
4146   int ShufIdxs[16];
4147   switch (OpNum) {
4148   default: llvm_unreachable("Unknown i32 permute!");
4149   case OP_VMRGHW:
4150     ShufIdxs[ 0] =  0; ShufIdxs[ 1] =  1; ShufIdxs[ 2] =  2; ShufIdxs[ 3] =  3;
4151     ShufIdxs[ 4] = 16; ShufIdxs[ 5] = 17; ShufIdxs[ 6] = 18; ShufIdxs[ 7] = 19;
4152     ShufIdxs[ 8] =  4; ShufIdxs[ 9] =  5; ShufIdxs[10] =  6; ShufIdxs[11] =  7;
4153     ShufIdxs[12] = 20; ShufIdxs[13] = 21; ShufIdxs[14] = 22; ShufIdxs[15] = 23;
4154     break;
4155   case OP_VMRGLW:
4156     ShufIdxs[ 0] =  8; ShufIdxs[ 1] =  9; ShufIdxs[ 2] = 10; ShufIdxs[ 3] = 11;
4157     ShufIdxs[ 4] = 24; ShufIdxs[ 5] = 25; ShufIdxs[ 6] = 26; ShufIdxs[ 7] = 27;
4158     ShufIdxs[ 8] = 12; ShufIdxs[ 9] = 13; ShufIdxs[10] = 14; ShufIdxs[11] = 15;
4159     ShufIdxs[12] = 28; ShufIdxs[13] = 29; ShufIdxs[14] = 30; ShufIdxs[15] = 31;
4160     break;
4161   case OP_VSPLTISW0:
4162     for (unsigned i = 0; i != 16; ++i)
4163       ShufIdxs[i] = (i&3)+0;
4164     break;
4165   case OP_VSPLTISW1:
4166     for (unsigned i = 0; i != 16; ++i)
4167       ShufIdxs[i] = (i&3)+4;
4168     break;
4169   case OP_VSPLTISW2:
4170     for (unsigned i = 0; i != 16; ++i)
4171       ShufIdxs[i] = (i&3)+8;
4172     break;
4173   case OP_VSPLTISW3:
4174     for (unsigned i = 0; i != 16; ++i)
4175       ShufIdxs[i] = (i&3)+12;
4176     break;
4177   case OP_VSLDOI4:
4178     return BuildVSLDOI(OpLHS, OpRHS, 4, OpLHS.getValueType(), DAG, dl);
4179   case OP_VSLDOI8:
4180     return BuildVSLDOI(OpLHS, OpRHS, 8, OpLHS.getValueType(), DAG, dl);
4181   case OP_VSLDOI12:
4182     return BuildVSLDOI(OpLHS, OpRHS, 12, OpLHS.getValueType(), DAG, dl);
4183   }
4184   EVT VT = OpLHS.getValueType();
4185   OpLHS = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, OpLHS);
4186   OpRHS = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, OpRHS);
4187   SDValue T = DAG.getVectorShuffle(MVT::v16i8, dl, OpLHS, OpRHS, ShufIdxs);
4188   return DAG.getNode(ISD::BITCAST, dl, VT, T);
4189 }
4190 
4191 /// LowerVECTOR_SHUFFLE - Return the code we lower for VECTOR_SHUFFLE.  If this
4192 /// is a shuffle we can handle in a single instruction, return it.  Otherwise,
4193 /// return the code it can be lowered into.  Worst case, it can always be
4194 /// lowered into a vperm.
LowerVECTOR_SHUFFLE(SDValue Op,SelectionDAG & DAG) const4195 SDValue PPCTargetLowering::LowerVECTOR_SHUFFLE(SDValue Op,
4196                                                SelectionDAG &DAG) const {
4197   DebugLoc dl = Op.getDebugLoc();
4198   SDValue V1 = Op.getOperand(0);
4199   SDValue V2 = Op.getOperand(1);
4200   ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(Op);
4201   EVT VT = Op.getValueType();
4202 
4203   // Cases that are handled by instructions that take permute immediates
4204   // (such as vsplt*) should be left as VECTOR_SHUFFLE nodes so they can be
4205   // selected by the instruction selector.
4206   if (V2.getOpcode() == ISD::UNDEF) {
4207     if (PPC::isSplatShuffleMask(SVOp, 1) ||
4208         PPC::isSplatShuffleMask(SVOp, 2) ||
4209         PPC::isSplatShuffleMask(SVOp, 4) ||
4210         PPC::isVPKUWUMShuffleMask(SVOp, true) ||
4211         PPC::isVPKUHUMShuffleMask(SVOp, true) ||
4212         PPC::isVSLDOIShuffleMask(SVOp, true) != -1 ||
4213         PPC::isVMRGLShuffleMask(SVOp, 1, true) ||
4214         PPC::isVMRGLShuffleMask(SVOp, 2, true) ||
4215         PPC::isVMRGLShuffleMask(SVOp, 4, true) ||
4216         PPC::isVMRGHShuffleMask(SVOp, 1, true) ||
4217         PPC::isVMRGHShuffleMask(SVOp, 2, true) ||
4218         PPC::isVMRGHShuffleMask(SVOp, 4, true)) {
4219       return Op;
4220     }
4221   }
4222 
4223   // Altivec has a variety of "shuffle immediates" that take two vector inputs
4224   // and produce a fixed permutation.  If any of these match, do not lower to
4225   // VPERM.
4226   if (PPC::isVPKUWUMShuffleMask(SVOp, false) ||
4227       PPC::isVPKUHUMShuffleMask(SVOp, false) ||
4228       PPC::isVSLDOIShuffleMask(SVOp, false) != -1 ||
4229       PPC::isVMRGLShuffleMask(SVOp, 1, false) ||
4230       PPC::isVMRGLShuffleMask(SVOp, 2, false) ||
4231       PPC::isVMRGLShuffleMask(SVOp, 4, false) ||
4232       PPC::isVMRGHShuffleMask(SVOp, 1, false) ||
4233       PPC::isVMRGHShuffleMask(SVOp, 2, false) ||
4234       PPC::isVMRGHShuffleMask(SVOp, 4, false))
4235     return Op;
4236 
4237   // Check to see if this is a shuffle of 4-byte values.  If so, we can use our
4238   // perfect shuffle table to emit an optimal matching sequence.
4239   SmallVector<int, 16> PermMask;
4240   SVOp->getMask(PermMask);
4241 
4242   unsigned PFIndexes[4];
4243   bool isFourElementShuffle = true;
4244   for (unsigned i = 0; i != 4 && isFourElementShuffle; ++i) { // Element number
4245     unsigned EltNo = 8;   // Start out undef.
4246     for (unsigned j = 0; j != 4; ++j) {  // Intra-element byte.
4247       if (PermMask[i*4+j] < 0)
4248         continue;   // Undef, ignore it.
4249 
4250       unsigned ByteSource = PermMask[i*4+j];
4251       if ((ByteSource & 3) != j) {
4252         isFourElementShuffle = false;
4253         break;
4254       }
4255 
4256       if (EltNo == 8) {
4257         EltNo = ByteSource/4;
4258       } else if (EltNo != ByteSource/4) {
4259         isFourElementShuffle = false;
4260         break;
4261       }
4262     }
4263     PFIndexes[i] = EltNo;
4264   }
4265 
4266   // If this shuffle can be expressed as a shuffle of 4-byte elements, use the
4267   // perfect shuffle vector to determine if it is cost effective to do this as
4268   // discrete instructions, or whether we should use a vperm.
4269   if (isFourElementShuffle) {
4270     // Compute the index in the perfect shuffle table.
4271     unsigned PFTableIndex =
4272       PFIndexes[0]*9*9*9+PFIndexes[1]*9*9+PFIndexes[2]*9+PFIndexes[3];
4273 
4274     unsigned PFEntry = PerfectShuffleTable[PFTableIndex];
4275     unsigned Cost  = (PFEntry >> 30);
4276 
4277     // Determining when to avoid vperm is tricky.  Many things affect the cost
4278     // of vperm, particularly how many times the perm mask needs to be computed.
4279     // For example, if the perm mask can be hoisted out of a loop or is already
4280     // used (perhaps because there are multiple permutes with the same shuffle
4281     // mask?) the vperm has a cost of 1.  OTOH, hoisting the permute mask out of
4282     // the loop requires an extra register.
4283     //
4284     // As a compromise, we only emit discrete instructions if the shuffle can be
4285     // generated in 3 or fewer operations.  When we have loop information
4286     // available, if this block is within a loop, we should avoid using vperm
4287     // for 3-operation perms and use a constant pool load instead.
4288     if (Cost < 3)
4289       return GeneratePerfectShuffle(PFEntry, V1, V2, DAG, dl);
4290   }
4291 
4292   // Lower this to a VPERM(V1, V2, V3) expression, where V3 is a constant
4293   // vector that will get spilled to the constant pool.
4294   if (V2.getOpcode() == ISD::UNDEF) V2 = V1;
4295 
4296   // The SHUFFLE_VECTOR mask is almost exactly what we want for vperm, except
4297   // that it is in input element units, not in bytes.  Convert now.
4298   EVT EltVT = V1.getValueType().getVectorElementType();
4299   unsigned BytesPerElement = EltVT.getSizeInBits()/8;
4300 
4301   SmallVector<SDValue, 16> ResultMask;
4302   for (unsigned i = 0, e = VT.getVectorNumElements(); i != e; ++i) {
4303     unsigned SrcElt = PermMask[i] < 0 ? 0 : PermMask[i];
4304 
4305     for (unsigned j = 0; j != BytesPerElement; ++j)
4306       ResultMask.push_back(DAG.getConstant(SrcElt*BytesPerElement+j,
4307                                            MVT::i32));
4308   }
4309 
4310   SDValue VPermMask = DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v16i8,
4311                                     &ResultMask[0], ResultMask.size());
4312   return DAG.getNode(PPCISD::VPERM, dl, V1.getValueType(), V1, V2, VPermMask);
4313 }
4314 
4315 /// getAltivecCompareInfo - Given an intrinsic, return false if it is not an
4316 /// altivec comparison.  If it is, return true and fill in Opc/isDot with
4317 /// information about the intrinsic.
getAltivecCompareInfo(SDValue Intrin,int & CompareOpc,bool & isDot)4318 static bool getAltivecCompareInfo(SDValue Intrin, int &CompareOpc,
4319                                   bool &isDot) {
4320   unsigned IntrinsicID =
4321     cast<ConstantSDNode>(Intrin.getOperand(0))->getZExtValue();
4322   CompareOpc = -1;
4323   isDot = false;
4324   switch (IntrinsicID) {
4325   default: return false;
4326     // Comparison predicates.
4327   case Intrinsic::ppc_altivec_vcmpbfp_p:  CompareOpc = 966; isDot = 1; break;
4328   case Intrinsic::ppc_altivec_vcmpeqfp_p: CompareOpc = 198; isDot = 1; break;
4329   case Intrinsic::ppc_altivec_vcmpequb_p: CompareOpc =   6; isDot = 1; break;
4330   case Intrinsic::ppc_altivec_vcmpequh_p: CompareOpc =  70; isDot = 1; break;
4331   case Intrinsic::ppc_altivec_vcmpequw_p: CompareOpc = 134; isDot = 1; break;
4332   case Intrinsic::ppc_altivec_vcmpgefp_p: CompareOpc = 454; isDot = 1; break;
4333   case Intrinsic::ppc_altivec_vcmpgtfp_p: CompareOpc = 710; isDot = 1; break;
4334   case Intrinsic::ppc_altivec_vcmpgtsb_p: CompareOpc = 774; isDot = 1; break;
4335   case Intrinsic::ppc_altivec_vcmpgtsh_p: CompareOpc = 838; isDot = 1; break;
4336   case Intrinsic::ppc_altivec_vcmpgtsw_p: CompareOpc = 902; isDot = 1; break;
4337   case Intrinsic::ppc_altivec_vcmpgtub_p: CompareOpc = 518; isDot = 1; break;
4338   case Intrinsic::ppc_altivec_vcmpgtuh_p: CompareOpc = 582; isDot = 1; break;
4339   case Intrinsic::ppc_altivec_vcmpgtuw_p: CompareOpc = 646; isDot = 1; break;
4340 
4341     // Normal Comparisons.
4342   case Intrinsic::ppc_altivec_vcmpbfp:    CompareOpc = 966; isDot = 0; break;
4343   case Intrinsic::ppc_altivec_vcmpeqfp:   CompareOpc = 198; isDot = 0; break;
4344   case Intrinsic::ppc_altivec_vcmpequb:   CompareOpc =   6; isDot = 0; break;
4345   case Intrinsic::ppc_altivec_vcmpequh:   CompareOpc =  70; isDot = 0; break;
4346   case Intrinsic::ppc_altivec_vcmpequw:   CompareOpc = 134; isDot = 0; break;
4347   case Intrinsic::ppc_altivec_vcmpgefp:   CompareOpc = 454; isDot = 0; break;
4348   case Intrinsic::ppc_altivec_vcmpgtfp:   CompareOpc = 710; isDot = 0; break;
4349   case Intrinsic::ppc_altivec_vcmpgtsb:   CompareOpc = 774; isDot = 0; break;
4350   case Intrinsic::ppc_altivec_vcmpgtsh:   CompareOpc = 838; isDot = 0; break;
4351   case Intrinsic::ppc_altivec_vcmpgtsw:   CompareOpc = 902; isDot = 0; break;
4352   case Intrinsic::ppc_altivec_vcmpgtub:   CompareOpc = 518; isDot = 0; break;
4353   case Intrinsic::ppc_altivec_vcmpgtuh:   CompareOpc = 582; isDot = 0; break;
4354   case Intrinsic::ppc_altivec_vcmpgtuw:   CompareOpc = 646; isDot = 0; break;
4355   }
4356   return true;
4357 }
4358 
4359 /// LowerINTRINSIC_WO_CHAIN - If this is an intrinsic that we want to custom
4360 /// lower, do it, otherwise return null.
LowerINTRINSIC_WO_CHAIN(SDValue Op,SelectionDAG & DAG) const4361 SDValue PPCTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op,
4362                                                    SelectionDAG &DAG) const {
4363   // If this is a lowered altivec predicate compare, CompareOpc is set to the
4364   // opcode number of the comparison.
4365   DebugLoc dl = Op.getDebugLoc();
4366   int CompareOpc;
4367   bool isDot;
4368   if (!getAltivecCompareInfo(Op, CompareOpc, isDot))
4369     return SDValue();    // Don't custom lower most intrinsics.
4370 
4371   // If this is a non-dot comparison, make the VCMP node and we are done.
4372   if (!isDot) {
4373     SDValue Tmp = DAG.getNode(PPCISD::VCMP, dl, Op.getOperand(2).getValueType(),
4374                               Op.getOperand(1), Op.getOperand(2),
4375                               DAG.getConstant(CompareOpc, MVT::i32));
4376     return DAG.getNode(ISD::BITCAST, dl, Op.getValueType(), Tmp);
4377   }
4378 
4379   // Create the PPCISD altivec 'dot' comparison node.
4380   SDValue Ops[] = {
4381     Op.getOperand(2),  // LHS
4382     Op.getOperand(3),  // RHS
4383     DAG.getConstant(CompareOpc, MVT::i32)
4384   };
4385   std::vector<EVT> VTs;
4386   VTs.push_back(Op.getOperand(2).getValueType());
4387   VTs.push_back(MVT::Glue);
4388   SDValue CompNode = DAG.getNode(PPCISD::VCMPo, dl, VTs, Ops, 3);
4389 
4390   // Now that we have the comparison, emit a copy from the CR to a GPR.
4391   // This is flagged to the above dot comparison.
4392   SDValue Flags = DAG.getNode(PPCISD::MFCR, dl, MVT::i32,
4393                                 DAG.getRegister(PPC::CR6, MVT::i32),
4394                                 CompNode.getValue(1));
4395 
4396   // Unpack the result based on how the target uses it.
4397   unsigned BitNo;   // Bit # of CR6.
4398   bool InvertBit;   // Invert result?
4399   switch (cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue()) {
4400   default:  // Can't happen, don't crash on invalid number though.
4401   case 0:   // Return the value of the EQ bit of CR6.
4402     BitNo = 0; InvertBit = false;
4403     break;
4404   case 1:   // Return the inverted value of the EQ bit of CR6.
4405     BitNo = 0; InvertBit = true;
4406     break;
4407   case 2:   // Return the value of the LT bit of CR6.
4408     BitNo = 2; InvertBit = false;
4409     break;
4410   case 3:   // Return the inverted value of the LT bit of CR6.
4411     BitNo = 2; InvertBit = true;
4412     break;
4413   }
4414 
4415   // Shift the bit into the low position.
4416   Flags = DAG.getNode(ISD::SRL, dl, MVT::i32, Flags,
4417                       DAG.getConstant(8-(3-BitNo), MVT::i32));
4418   // Isolate the bit.
4419   Flags = DAG.getNode(ISD::AND, dl, MVT::i32, Flags,
4420                       DAG.getConstant(1, MVT::i32));
4421 
4422   // If we are supposed to, toggle the bit.
4423   if (InvertBit)
4424     Flags = DAG.getNode(ISD::XOR, dl, MVT::i32, Flags,
4425                         DAG.getConstant(1, MVT::i32));
4426   return Flags;
4427 }
4428 
LowerSCALAR_TO_VECTOR(SDValue Op,SelectionDAG & DAG) const4429 SDValue PPCTargetLowering::LowerSCALAR_TO_VECTOR(SDValue Op,
4430                                                    SelectionDAG &DAG) const {
4431   DebugLoc dl = Op.getDebugLoc();
4432   // Create a stack slot that is 16-byte aligned.
4433   MachineFrameInfo *FrameInfo = DAG.getMachineFunction().getFrameInfo();
4434   int FrameIdx = FrameInfo->CreateStackObject(16, 16, false);
4435   EVT PtrVT = getPointerTy();
4436   SDValue FIdx = DAG.getFrameIndex(FrameIdx, PtrVT);
4437 
4438   // Store the input value into Value#0 of the stack slot.
4439   SDValue Store = DAG.getStore(DAG.getEntryNode(), dl,
4440                                Op.getOperand(0), FIdx, MachinePointerInfo(),
4441                                false, false, 0);
4442   // Load it out.
4443   return DAG.getLoad(Op.getValueType(), dl, Store, FIdx, MachinePointerInfo(),
4444                      false, false, 0);
4445 }
4446 
LowerMUL(SDValue Op,SelectionDAG & DAG) const4447 SDValue PPCTargetLowering::LowerMUL(SDValue Op, SelectionDAG &DAG) const {
4448   DebugLoc dl = Op.getDebugLoc();
4449   if (Op.getValueType() == MVT::v4i32) {
4450     SDValue LHS = Op.getOperand(0), RHS = Op.getOperand(1);
4451 
4452     SDValue Zero  = BuildSplatI(  0, 1, MVT::v4i32, DAG, dl);
4453     SDValue Neg16 = BuildSplatI(-16, 4, MVT::v4i32, DAG, dl);//+16 as shift amt.
4454 
4455     SDValue RHSSwap =   // = vrlw RHS, 16
4456       BuildIntrinsicOp(Intrinsic::ppc_altivec_vrlw, RHS, Neg16, DAG, dl);
4457 
4458     // Shrinkify inputs to v8i16.
4459     LHS = DAG.getNode(ISD::BITCAST, dl, MVT::v8i16, LHS);
4460     RHS = DAG.getNode(ISD::BITCAST, dl, MVT::v8i16, RHS);
4461     RHSSwap = DAG.getNode(ISD::BITCAST, dl, MVT::v8i16, RHSSwap);
4462 
4463     // Low parts multiplied together, generating 32-bit results (we ignore the
4464     // top parts).
4465     SDValue LoProd = BuildIntrinsicOp(Intrinsic::ppc_altivec_vmulouh,
4466                                         LHS, RHS, DAG, dl, MVT::v4i32);
4467 
4468     SDValue HiProd = BuildIntrinsicOp(Intrinsic::ppc_altivec_vmsumuhm,
4469                                       LHS, RHSSwap, Zero, DAG, dl, MVT::v4i32);
4470     // Shift the high parts up 16 bits.
4471     HiProd = BuildIntrinsicOp(Intrinsic::ppc_altivec_vslw, HiProd,
4472                               Neg16, DAG, dl);
4473     return DAG.getNode(ISD::ADD, dl, MVT::v4i32, LoProd, HiProd);
4474   } else if (Op.getValueType() == MVT::v8i16) {
4475     SDValue LHS = Op.getOperand(0), RHS = Op.getOperand(1);
4476 
4477     SDValue Zero = BuildSplatI(0, 1, MVT::v8i16, DAG, dl);
4478 
4479     return BuildIntrinsicOp(Intrinsic::ppc_altivec_vmladduhm,
4480                             LHS, RHS, Zero, DAG, dl);
4481   } else if (Op.getValueType() == MVT::v16i8) {
4482     SDValue LHS = Op.getOperand(0), RHS = Op.getOperand(1);
4483 
4484     // Multiply the even 8-bit parts, producing 16-bit sums.
4485     SDValue EvenParts = BuildIntrinsicOp(Intrinsic::ppc_altivec_vmuleub,
4486                                            LHS, RHS, DAG, dl, MVT::v8i16);
4487     EvenParts = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, EvenParts);
4488 
4489     // Multiply the odd 8-bit parts, producing 16-bit sums.
4490     SDValue OddParts = BuildIntrinsicOp(Intrinsic::ppc_altivec_vmuloub,
4491                                           LHS, RHS, DAG, dl, MVT::v8i16);
4492     OddParts = DAG.getNode(ISD::BITCAST, dl, MVT::v16i8, OddParts);
4493 
4494     // Merge the results together.
4495     int Ops[16];
4496     for (unsigned i = 0; i != 8; ++i) {
4497       Ops[i*2  ] = 2*i+1;
4498       Ops[i*2+1] = 2*i+1+16;
4499     }
4500     return DAG.getVectorShuffle(MVT::v16i8, dl, EvenParts, OddParts, Ops);
4501   } else {
4502     llvm_unreachable("Unknown mul to lower!");
4503   }
4504 }
4505 
4506 /// LowerOperation - Provide custom lowering hooks for some operations.
4507 ///
LowerOperation(SDValue Op,SelectionDAG & DAG) const4508 SDValue PPCTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
4509   switch (Op.getOpcode()) {
4510   default: llvm_unreachable("Wasn't expecting to be able to lower this!");
4511   case ISD::ConstantPool:       return LowerConstantPool(Op, DAG);
4512   case ISD::BlockAddress:       return LowerBlockAddress(Op, DAG);
4513   case ISD::GlobalAddress:      return LowerGlobalAddress(Op, DAG);
4514   case ISD::GlobalTLSAddress:   llvm_unreachable("TLS not implemented for PPC");
4515   case ISD::JumpTable:          return LowerJumpTable(Op, DAG);
4516   case ISD::SETCC:              return LowerSETCC(Op, DAG);
4517   case ISD::INIT_TRAMPOLINE:    return LowerINIT_TRAMPOLINE(Op, DAG);
4518   case ISD::ADJUST_TRAMPOLINE:  return LowerADJUST_TRAMPOLINE(Op, DAG);
4519   case ISD::VASTART:
4520     return LowerVASTART(Op, DAG, PPCSubTarget);
4521 
4522   case ISD::VAARG:
4523     return LowerVAARG(Op, DAG, PPCSubTarget);
4524 
4525   case ISD::STACKRESTORE:       return LowerSTACKRESTORE(Op, DAG, PPCSubTarget);
4526   case ISD::DYNAMIC_STACKALLOC:
4527     return LowerDYNAMIC_STACKALLOC(Op, DAG, PPCSubTarget);
4528 
4529   case ISD::SELECT_CC:          return LowerSELECT_CC(Op, DAG);
4530   case ISD::FP_TO_UINT:
4531   case ISD::FP_TO_SINT:         return LowerFP_TO_INT(Op, DAG,
4532                                                        Op.getDebugLoc());
4533   case ISD::SINT_TO_FP:         return LowerSINT_TO_FP(Op, DAG);
4534   case ISD::FLT_ROUNDS_:        return LowerFLT_ROUNDS_(Op, DAG);
4535 
4536   // Lower 64-bit shifts.
4537   case ISD::SHL_PARTS:          return LowerSHL_PARTS(Op, DAG);
4538   case ISD::SRL_PARTS:          return LowerSRL_PARTS(Op, DAG);
4539   case ISD::SRA_PARTS:          return LowerSRA_PARTS(Op, DAG);
4540 
4541   // Vector-related lowering.
4542   case ISD::BUILD_VECTOR:       return LowerBUILD_VECTOR(Op, DAG);
4543   case ISD::VECTOR_SHUFFLE:     return LowerVECTOR_SHUFFLE(Op, DAG);
4544   case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
4545   case ISD::SCALAR_TO_VECTOR:   return LowerSCALAR_TO_VECTOR(Op, DAG);
4546   case ISD::MUL:                return LowerMUL(Op, DAG);
4547 
4548   // Frame & Return address.
4549   case ISD::RETURNADDR:         return LowerRETURNADDR(Op, DAG);
4550   case ISD::FRAMEADDR:          return LowerFRAMEADDR(Op, DAG);
4551   }
4552   return SDValue();
4553 }
4554 
ReplaceNodeResults(SDNode * N,SmallVectorImpl<SDValue> & Results,SelectionDAG & DAG) const4555 void PPCTargetLowering::ReplaceNodeResults(SDNode *N,
4556                                            SmallVectorImpl<SDValue>&Results,
4557                                            SelectionDAG &DAG) const {
4558   const TargetMachine &TM = getTargetMachine();
4559   DebugLoc dl = N->getDebugLoc();
4560   switch (N->getOpcode()) {
4561   default:
4562     assert(false && "Do not know how to custom type legalize this operation!");
4563     return;
4564   case ISD::VAARG: {
4565     if (!TM.getSubtarget<PPCSubtarget>().isSVR4ABI()
4566         || TM.getSubtarget<PPCSubtarget>().isPPC64())
4567       return;
4568 
4569     EVT VT = N->getValueType(0);
4570 
4571     if (VT == MVT::i64) {
4572       SDValue NewNode = LowerVAARG(SDValue(N, 1), DAG, PPCSubTarget);
4573 
4574       Results.push_back(NewNode);
4575       Results.push_back(NewNode.getValue(1));
4576     }
4577     return;
4578   }
4579   case ISD::FP_ROUND_INREG: {
4580     assert(N->getValueType(0) == MVT::ppcf128);
4581     assert(N->getOperand(0).getValueType() == MVT::ppcf128);
4582     SDValue Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, dl,
4583                              MVT::f64, N->getOperand(0),
4584                              DAG.getIntPtrConstant(0));
4585     SDValue Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, dl,
4586                              MVT::f64, N->getOperand(0),
4587                              DAG.getIntPtrConstant(1));
4588 
4589     // This sequence changes FPSCR to do round-to-zero, adds the two halves
4590     // of the long double, and puts FPSCR back the way it was.  We do not
4591     // actually model FPSCR.
4592     std::vector<EVT> NodeTys;
4593     SDValue Ops[4], Result, MFFSreg, InFlag, FPreg;
4594 
4595     NodeTys.push_back(MVT::f64);   // Return register
4596     NodeTys.push_back(MVT::Glue);    // Returns a flag for later insns
4597     Result = DAG.getNode(PPCISD::MFFS, dl, NodeTys, &InFlag, 0);
4598     MFFSreg = Result.getValue(0);
4599     InFlag = Result.getValue(1);
4600 
4601     NodeTys.clear();
4602     NodeTys.push_back(MVT::Glue);   // Returns a flag
4603     Ops[0] = DAG.getConstant(31, MVT::i32);
4604     Ops[1] = InFlag;
4605     Result = DAG.getNode(PPCISD::MTFSB1, dl, NodeTys, Ops, 2);
4606     InFlag = Result.getValue(0);
4607 
4608     NodeTys.clear();
4609     NodeTys.push_back(MVT::Glue);   // Returns a flag
4610     Ops[0] = DAG.getConstant(30, MVT::i32);
4611     Ops[1] = InFlag;
4612     Result = DAG.getNode(PPCISD::MTFSB0, dl, NodeTys, Ops, 2);
4613     InFlag = Result.getValue(0);
4614 
4615     NodeTys.clear();
4616     NodeTys.push_back(MVT::f64);    // result of add
4617     NodeTys.push_back(MVT::Glue);   // Returns a flag
4618     Ops[0] = Lo;
4619     Ops[1] = Hi;
4620     Ops[2] = InFlag;
4621     Result = DAG.getNode(PPCISD::FADDRTZ, dl, NodeTys, Ops, 3);
4622     FPreg = Result.getValue(0);
4623     InFlag = Result.getValue(1);
4624 
4625     NodeTys.clear();
4626     NodeTys.push_back(MVT::f64);
4627     Ops[0] = DAG.getConstant(1, MVT::i32);
4628     Ops[1] = MFFSreg;
4629     Ops[2] = FPreg;
4630     Ops[3] = InFlag;
4631     Result = DAG.getNode(PPCISD::MTFSF, dl, NodeTys, Ops, 4);
4632     FPreg = Result.getValue(0);
4633 
4634     // We know the low half is about to be thrown away, so just use something
4635     // convenient.
4636     Results.push_back(DAG.getNode(ISD::BUILD_PAIR, dl, MVT::ppcf128,
4637                                 FPreg, FPreg));
4638     return;
4639   }
4640   case ISD::FP_TO_SINT:
4641     Results.push_back(LowerFP_TO_INT(SDValue(N, 0), DAG, dl));
4642     return;
4643   }
4644 }
4645 
4646 
4647 //===----------------------------------------------------------------------===//
4648 //  Other Lowering Code
4649 //===----------------------------------------------------------------------===//
4650 
4651 MachineBasicBlock *
EmitAtomicBinary(MachineInstr * MI,MachineBasicBlock * BB,bool is64bit,unsigned BinOpcode) const4652 PPCTargetLowering::EmitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
4653                                     bool is64bit, unsigned BinOpcode) const {
4654   // This also handles ATOMIC_SWAP, indicated by BinOpcode==0.
4655   const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
4656 
4657   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4658   MachineFunction *F = BB->getParent();
4659   MachineFunction::iterator It = BB;
4660   ++It;
4661 
4662   unsigned dest = MI->getOperand(0).getReg();
4663   unsigned ptrA = MI->getOperand(1).getReg();
4664   unsigned ptrB = MI->getOperand(2).getReg();
4665   unsigned incr = MI->getOperand(3).getReg();
4666   DebugLoc dl = MI->getDebugLoc();
4667 
4668   MachineBasicBlock *loopMBB = F->CreateMachineBasicBlock(LLVM_BB);
4669   MachineBasicBlock *exitMBB = F->CreateMachineBasicBlock(LLVM_BB);
4670   F->insert(It, loopMBB);
4671   F->insert(It, exitMBB);
4672   exitMBB->splice(exitMBB->begin(), BB,
4673                   llvm::next(MachineBasicBlock::iterator(MI)),
4674                   BB->end());
4675   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
4676 
4677   MachineRegisterInfo &RegInfo = F->getRegInfo();
4678   unsigned TmpReg = (!BinOpcode) ? incr :
4679     RegInfo.createVirtualRegister(
4680        is64bit ? (const TargetRegisterClass *) &PPC::G8RCRegClass :
4681                  (const TargetRegisterClass *) &PPC::GPRCRegClass);
4682 
4683   //  thisMBB:
4684   //   ...
4685   //   fallthrough --> loopMBB
4686   BB->addSuccessor(loopMBB);
4687 
4688   //  loopMBB:
4689   //   l[wd]arx dest, ptr
4690   //   add r0, dest, incr
4691   //   st[wd]cx. r0, ptr
4692   //   bne- loopMBB
4693   //   fallthrough --> exitMBB
4694   BB = loopMBB;
4695   BuildMI(BB, dl, TII->get(is64bit ? PPC::LDARX : PPC::LWARX), dest)
4696     .addReg(ptrA).addReg(ptrB);
4697   if (BinOpcode)
4698     BuildMI(BB, dl, TII->get(BinOpcode), TmpReg).addReg(incr).addReg(dest);
4699   BuildMI(BB, dl, TII->get(is64bit ? PPC::STDCX : PPC::STWCX))
4700     .addReg(TmpReg).addReg(ptrA).addReg(ptrB);
4701   BuildMI(BB, dl, TII->get(PPC::BCC))
4702     .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(loopMBB);
4703   BB->addSuccessor(loopMBB);
4704   BB->addSuccessor(exitMBB);
4705 
4706   //  exitMBB:
4707   //   ...
4708   BB = exitMBB;
4709   return BB;
4710 }
4711 
4712 MachineBasicBlock *
EmitPartwordAtomicBinary(MachineInstr * MI,MachineBasicBlock * BB,bool is8bit,unsigned BinOpcode) const4713 PPCTargetLowering::EmitPartwordAtomicBinary(MachineInstr *MI,
4714                                             MachineBasicBlock *BB,
4715                                             bool is8bit,    // operation
4716                                             unsigned BinOpcode) const {
4717   // This also handles ATOMIC_SWAP, indicated by BinOpcode==0.
4718   const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
4719   // In 64 bit mode we have to use 64 bits for addresses, even though the
4720   // lwarx/stwcx are 32 bits.  With the 32-bit atomics we can use address
4721   // registers without caring whether they're 32 or 64, but here we're
4722   // doing actual arithmetic on the addresses.
4723   bool is64bit = PPCSubTarget.isPPC64();
4724   unsigned ZeroReg = is64bit ? PPC::X0 : PPC::R0;
4725 
4726   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4727   MachineFunction *F = BB->getParent();
4728   MachineFunction::iterator It = BB;
4729   ++It;
4730 
4731   unsigned dest = MI->getOperand(0).getReg();
4732   unsigned ptrA = MI->getOperand(1).getReg();
4733   unsigned ptrB = MI->getOperand(2).getReg();
4734   unsigned incr = MI->getOperand(3).getReg();
4735   DebugLoc dl = MI->getDebugLoc();
4736 
4737   MachineBasicBlock *loopMBB = F->CreateMachineBasicBlock(LLVM_BB);
4738   MachineBasicBlock *exitMBB = F->CreateMachineBasicBlock(LLVM_BB);
4739   F->insert(It, loopMBB);
4740   F->insert(It, exitMBB);
4741   exitMBB->splice(exitMBB->begin(), BB,
4742                   llvm::next(MachineBasicBlock::iterator(MI)),
4743                   BB->end());
4744   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
4745 
4746   MachineRegisterInfo &RegInfo = F->getRegInfo();
4747   const TargetRegisterClass *RC =
4748     is64bit ? (const TargetRegisterClass *) &PPC::G8RCRegClass :
4749               (const TargetRegisterClass *) &PPC::GPRCRegClass;
4750   unsigned PtrReg = RegInfo.createVirtualRegister(RC);
4751   unsigned Shift1Reg = RegInfo.createVirtualRegister(RC);
4752   unsigned ShiftReg = RegInfo.createVirtualRegister(RC);
4753   unsigned Incr2Reg = RegInfo.createVirtualRegister(RC);
4754   unsigned MaskReg = RegInfo.createVirtualRegister(RC);
4755   unsigned Mask2Reg = RegInfo.createVirtualRegister(RC);
4756   unsigned Mask3Reg = RegInfo.createVirtualRegister(RC);
4757   unsigned Tmp2Reg = RegInfo.createVirtualRegister(RC);
4758   unsigned Tmp3Reg = RegInfo.createVirtualRegister(RC);
4759   unsigned Tmp4Reg = RegInfo.createVirtualRegister(RC);
4760   unsigned TmpDestReg = RegInfo.createVirtualRegister(RC);
4761   unsigned Ptr1Reg;
4762   unsigned TmpReg = (!BinOpcode) ? Incr2Reg : RegInfo.createVirtualRegister(RC);
4763 
4764   //  thisMBB:
4765   //   ...
4766   //   fallthrough --> loopMBB
4767   BB->addSuccessor(loopMBB);
4768 
4769   // The 4-byte load must be aligned, while a char or short may be
4770   // anywhere in the word.  Hence all this nasty bookkeeping code.
4771   //   add ptr1, ptrA, ptrB [copy if ptrA==0]
4772   //   rlwinm shift1, ptr1, 3, 27, 28 [3, 27, 27]
4773   //   xori shift, shift1, 24 [16]
4774   //   rlwinm ptr, ptr1, 0, 0, 29
4775   //   slw incr2, incr, shift
4776   //   li mask2, 255 [li mask3, 0; ori mask2, mask3, 65535]
4777   //   slw mask, mask2, shift
4778   //  loopMBB:
4779   //   lwarx tmpDest, ptr
4780   //   add tmp, tmpDest, incr2
4781   //   andc tmp2, tmpDest, mask
4782   //   and tmp3, tmp, mask
4783   //   or tmp4, tmp3, tmp2
4784   //   stwcx. tmp4, ptr
4785   //   bne- loopMBB
4786   //   fallthrough --> exitMBB
4787   //   srw dest, tmpDest, shift
4788   if (ptrA != ZeroReg) {
4789     Ptr1Reg = RegInfo.createVirtualRegister(RC);
4790     BuildMI(BB, dl, TII->get(is64bit ? PPC::ADD8 : PPC::ADD4), Ptr1Reg)
4791       .addReg(ptrA).addReg(ptrB);
4792   } else {
4793     Ptr1Reg = ptrB;
4794   }
4795   BuildMI(BB, dl, TII->get(PPC::RLWINM), Shift1Reg).addReg(Ptr1Reg)
4796       .addImm(3).addImm(27).addImm(is8bit ? 28 : 27);
4797   BuildMI(BB, dl, TII->get(is64bit ? PPC::XORI8 : PPC::XORI), ShiftReg)
4798       .addReg(Shift1Reg).addImm(is8bit ? 24 : 16);
4799   if (is64bit)
4800     BuildMI(BB, dl, TII->get(PPC::RLDICR), PtrReg)
4801       .addReg(Ptr1Reg).addImm(0).addImm(61);
4802   else
4803     BuildMI(BB, dl, TII->get(PPC::RLWINM), PtrReg)
4804       .addReg(Ptr1Reg).addImm(0).addImm(0).addImm(29);
4805   BuildMI(BB, dl, TII->get(PPC::SLW), Incr2Reg)
4806       .addReg(incr).addReg(ShiftReg);
4807   if (is8bit)
4808     BuildMI(BB, dl, TII->get(PPC::LI), Mask2Reg).addImm(255);
4809   else {
4810     BuildMI(BB, dl, TII->get(PPC::LI), Mask3Reg).addImm(0);
4811     BuildMI(BB, dl, TII->get(PPC::ORI),Mask2Reg).addReg(Mask3Reg).addImm(65535);
4812   }
4813   BuildMI(BB, dl, TII->get(PPC::SLW), MaskReg)
4814       .addReg(Mask2Reg).addReg(ShiftReg);
4815 
4816   BB = loopMBB;
4817   BuildMI(BB, dl, TII->get(PPC::LWARX), TmpDestReg)
4818     .addReg(ZeroReg).addReg(PtrReg);
4819   if (BinOpcode)
4820     BuildMI(BB, dl, TII->get(BinOpcode), TmpReg)
4821       .addReg(Incr2Reg).addReg(TmpDestReg);
4822   BuildMI(BB, dl, TII->get(is64bit ? PPC::ANDC8 : PPC::ANDC), Tmp2Reg)
4823     .addReg(TmpDestReg).addReg(MaskReg);
4824   BuildMI(BB, dl, TII->get(is64bit ? PPC::AND8 : PPC::AND), Tmp3Reg)
4825     .addReg(TmpReg).addReg(MaskReg);
4826   BuildMI(BB, dl, TII->get(is64bit ? PPC::OR8 : PPC::OR), Tmp4Reg)
4827     .addReg(Tmp3Reg).addReg(Tmp2Reg);
4828   BuildMI(BB, dl, TII->get(is64bit ? PPC::STDCX : PPC::STWCX))
4829     .addReg(Tmp4Reg).addReg(ZeroReg).addReg(PtrReg);
4830   BuildMI(BB, dl, TII->get(PPC::BCC))
4831     .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(loopMBB);
4832   BB->addSuccessor(loopMBB);
4833   BB->addSuccessor(exitMBB);
4834 
4835   //  exitMBB:
4836   //   ...
4837   BB = exitMBB;
4838   BuildMI(*BB, BB->begin(), dl, TII->get(PPC::SRW), dest).addReg(TmpDestReg)
4839     .addReg(ShiftReg);
4840   return BB;
4841 }
4842 
4843 MachineBasicBlock *
EmitInstrWithCustomInserter(MachineInstr * MI,MachineBasicBlock * BB) const4844 PPCTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
4845                                                MachineBasicBlock *BB) const {
4846   const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
4847 
4848   // To "insert" these instructions we actually have to insert their
4849   // control-flow patterns.
4850   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4851   MachineFunction::iterator It = BB;
4852   ++It;
4853 
4854   MachineFunction *F = BB->getParent();
4855 
4856   if (MI->getOpcode() == PPC::SELECT_CC_I4 ||
4857       MI->getOpcode() == PPC::SELECT_CC_I8 ||
4858       MI->getOpcode() == PPC::SELECT_CC_F4 ||
4859       MI->getOpcode() == PPC::SELECT_CC_F8 ||
4860       MI->getOpcode() == PPC::SELECT_CC_VRRC) {
4861 
4862     // The incoming instruction knows the destination vreg to set, the
4863     // condition code register to branch on, the true/false values to
4864     // select between, and a branch opcode to use.
4865 
4866     //  thisMBB:
4867     //  ...
4868     //   TrueVal = ...
4869     //   cmpTY ccX, r1, r2
4870     //   bCC copy1MBB
4871     //   fallthrough --> copy0MBB
4872     MachineBasicBlock *thisMBB = BB;
4873     MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
4874     MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
4875     unsigned SelectPred = MI->getOperand(4).getImm();
4876     DebugLoc dl = MI->getDebugLoc();
4877     F->insert(It, copy0MBB);
4878     F->insert(It, sinkMBB);
4879 
4880     // Transfer the remainder of BB and its successor edges to sinkMBB.
4881     sinkMBB->splice(sinkMBB->begin(), BB,
4882                     llvm::next(MachineBasicBlock::iterator(MI)),
4883                     BB->end());
4884     sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
4885 
4886     // Next, add the true and fallthrough blocks as its successors.
4887     BB->addSuccessor(copy0MBB);
4888     BB->addSuccessor(sinkMBB);
4889 
4890     BuildMI(BB, dl, TII->get(PPC::BCC))
4891       .addImm(SelectPred).addReg(MI->getOperand(1).getReg()).addMBB(sinkMBB);
4892 
4893     //  copy0MBB:
4894     //   %FalseValue = ...
4895     //   # fallthrough to sinkMBB
4896     BB = copy0MBB;
4897 
4898     // Update machine-CFG edges
4899     BB->addSuccessor(sinkMBB);
4900 
4901     //  sinkMBB:
4902     //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
4903     //  ...
4904     BB = sinkMBB;
4905     BuildMI(*BB, BB->begin(), dl,
4906             TII->get(PPC::PHI), MI->getOperand(0).getReg())
4907       .addReg(MI->getOperand(3).getReg()).addMBB(copy0MBB)
4908       .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
4909   }
4910   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_ADD_I8)
4911     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::ADD4);
4912   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_ADD_I16)
4913     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::ADD4);
4914   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_ADD_I32)
4915     BB = EmitAtomicBinary(MI, BB, false, PPC::ADD4);
4916   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_ADD_I64)
4917     BB = EmitAtomicBinary(MI, BB, true, PPC::ADD8);
4918 
4919   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_AND_I8)
4920     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::AND);
4921   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_AND_I16)
4922     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::AND);
4923   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_AND_I32)
4924     BB = EmitAtomicBinary(MI, BB, false, PPC::AND);
4925   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_AND_I64)
4926     BB = EmitAtomicBinary(MI, BB, true, PPC::AND8);
4927 
4928   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_OR_I8)
4929     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::OR);
4930   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_OR_I16)
4931     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::OR);
4932   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_OR_I32)
4933     BB = EmitAtomicBinary(MI, BB, false, PPC::OR);
4934   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_OR_I64)
4935     BB = EmitAtomicBinary(MI, BB, true, PPC::OR8);
4936 
4937   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_XOR_I8)
4938     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::XOR);
4939   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_XOR_I16)
4940     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::XOR);
4941   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_XOR_I32)
4942     BB = EmitAtomicBinary(MI, BB, false, PPC::XOR);
4943   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_XOR_I64)
4944     BB = EmitAtomicBinary(MI, BB, true, PPC::XOR8);
4945 
4946   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_NAND_I8)
4947     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::ANDC);
4948   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_NAND_I16)
4949     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::ANDC);
4950   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_NAND_I32)
4951     BB = EmitAtomicBinary(MI, BB, false, PPC::ANDC);
4952   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_NAND_I64)
4953     BB = EmitAtomicBinary(MI, BB, true, PPC::ANDC8);
4954 
4955   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_SUB_I8)
4956     BB = EmitPartwordAtomicBinary(MI, BB, true, PPC::SUBF);
4957   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_SUB_I16)
4958     BB = EmitPartwordAtomicBinary(MI, BB, false, PPC::SUBF);
4959   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_SUB_I32)
4960     BB = EmitAtomicBinary(MI, BB, false, PPC::SUBF);
4961   else if (MI->getOpcode() == PPC::ATOMIC_LOAD_SUB_I64)
4962     BB = EmitAtomicBinary(MI, BB, true, PPC::SUBF8);
4963 
4964   else if (MI->getOpcode() == PPC::ATOMIC_SWAP_I8)
4965     BB = EmitPartwordAtomicBinary(MI, BB, true, 0);
4966   else if (MI->getOpcode() == PPC::ATOMIC_SWAP_I16)
4967     BB = EmitPartwordAtomicBinary(MI, BB, false, 0);
4968   else if (MI->getOpcode() == PPC::ATOMIC_SWAP_I32)
4969     BB = EmitAtomicBinary(MI, BB, false, 0);
4970   else if (MI->getOpcode() == PPC::ATOMIC_SWAP_I64)
4971     BB = EmitAtomicBinary(MI, BB, true, 0);
4972 
4973   else if (MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I32 ||
4974            MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I64) {
4975     bool is64bit = MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I64;
4976 
4977     unsigned dest   = MI->getOperand(0).getReg();
4978     unsigned ptrA   = MI->getOperand(1).getReg();
4979     unsigned ptrB   = MI->getOperand(2).getReg();
4980     unsigned oldval = MI->getOperand(3).getReg();
4981     unsigned newval = MI->getOperand(4).getReg();
4982     DebugLoc dl     = MI->getDebugLoc();
4983 
4984     MachineBasicBlock *loop1MBB = F->CreateMachineBasicBlock(LLVM_BB);
4985     MachineBasicBlock *loop2MBB = F->CreateMachineBasicBlock(LLVM_BB);
4986     MachineBasicBlock *midMBB = F->CreateMachineBasicBlock(LLVM_BB);
4987     MachineBasicBlock *exitMBB = F->CreateMachineBasicBlock(LLVM_BB);
4988     F->insert(It, loop1MBB);
4989     F->insert(It, loop2MBB);
4990     F->insert(It, midMBB);
4991     F->insert(It, exitMBB);
4992     exitMBB->splice(exitMBB->begin(), BB,
4993                     llvm::next(MachineBasicBlock::iterator(MI)),
4994                     BB->end());
4995     exitMBB->transferSuccessorsAndUpdatePHIs(BB);
4996 
4997     //  thisMBB:
4998     //   ...
4999     //   fallthrough --> loopMBB
5000     BB->addSuccessor(loop1MBB);
5001 
5002     // loop1MBB:
5003     //   l[wd]arx dest, ptr
5004     //   cmp[wd] dest, oldval
5005     //   bne- midMBB
5006     // loop2MBB:
5007     //   st[wd]cx. newval, ptr
5008     //   bne- loopMBB
5009     //   b exitBB
5010     // midMBB:
5011     //   st[wd]cx. dest, ptr
5012     // exitBB:
5013     BB = loop1MBB;
5014     BuildMI(BB, dl, TII->get(is64bit ? PPC::LDARX : PPC::LWARX), dest)
5015       .addReg(ptrA).addReg(ptrB);
5016     BuildMI(BB, dl, TII->get(is64bit ? PPC::CMPD : PPC::CMPW), PPC::CR0)
5017       .addReg(oldval).addReg(dest);
5018     BuildMI(BB, dl, TII->get(PPC::BCC))
5019       .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(midMBB);
5020     BB->addSuccessor(loop2MBB);
5021     BB->addSuccessor(midMBB);
5022 
5023     BB = loop2MBB;
5024     BuildMI(BB, dl, TII->get(is64bit ? PPC::STDCX : PPC::STWCX))
5025       .addReg(newval).addReg(ptrA).addReg(ptrB);
5026     BuildMI(BB, dl, TII->get(PPC::BCC))
5027       .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(loop1MBB);
5028     BuildMI(BB, dl, TII->get(PPC::B)).addMBB(exitMBB);
5029     BB->addSuccessor(loop1MBB);
5030     BB->addSuccessor(exitMBB);
5031 
5032     BB = midMBB;
5033     BuildMI(BB, dl, TII->get(is64bit ? PPC::STDCX : PPC::STWCX))
5034       .addReg(dest).addReg(ptrA).addReg(ptrB);
5035     BB->addSuccessor(exitMBB);
5036 
5037     //  exitMBB:
5038     //   ...
5039     BB = exitMBB;
5040   } else if (MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I8 ||
5041              MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I16) {
5042     // We must use 64-bit registers for addresses when targeting 64-bit,
5043     // since we're actually doing arithmetic on them.  Other registers
5044     // can be 32-bit.
5045     bool is64bit = PPCSubTarget.isPPC64();
5046     bool is8bit = MI->getOpcode() == PPC::ATOMIC_CMP_SWAP_I8;
5047 
5048     unsigned dest   = MI->getOperand(0).getReg();
5049     unsigned ptrA   = MI->getOperand(1).getReg();
5050     unsigned ptrB   = MI->getOperand(2).getReg();
5051     unsigned oldval = MI->getOperand(3).getReg();
5052     unsigned newval = MI->getOperand(4).getReg();
5053     DebugLoc dl     = MI->getDebugLoc();
5054 
5055     MachineBasicBlock *loop1MBB = F->CreateMachineBasicBlock(LLVM_BB);
5056     MachineBasicBlock *loop2MBB = F->CreateMachineBasicBlock(LLVM_BB);
5057     MachineBasicBlock *midMBB = F->CreateMachineBasicBlock(LLVM_BB);
5058     MachineBasicBlock *exitMBB = F->CreateMachineBasicBlock(LLVM_BB);
5059     F->insert(It, loop1MBB);
5060     F->insert(It, loop2MBB);
5061     F->insert(It, midMBB);
5062     F->insert(It, exitMBB);
5063     exitMBB->splice(exitMBB->begin(), BB,
5064                     llvm::next(MachineBasicBlock::iterator(MI)),
5065                     BB->end());
5066     exitMBB->transferSuccessorsAndUpdatePHIs(BB);
5067 
5068     MachineRegisterInfo &RegInfo = F->getRegInfo();
5069     const TargetRegisterClass *RC =
5070       is64bit ? (const TargetRegisterClass *) &PPC::G8RCRegClass :
5071                 (const TargetRegisterClass *) &PPC::GPRCRegClass;
5072     unsigned PtrReg = RegInfo.createVirtualRegister(RC);
5073     unsigned Shift1Reg = RegInfo.createVirtualRegister(RC);
5074     unsigned ShiftReg = RegInfo.createVirtualRegister(RC);
5075     unsigned NewVal2Reg = RegInfo.createVirtualRegister(RC);
5076     unsigned NewVal3Reg = RegInfo.createVirtualRegister(RC);
5077     unsigned OldVal2Reg = RegInfo.createVirtualRegister(RC);
5078     unsigned OldVal3Reg = RegInfo.createVirtualRegister(RC);
5079     unsigned MaskReg = RegInfo.createVirtualRegister(RC);
5080     unsigned Mask2Reg = RegInfo.createVirtualRegister(RC);
5081     unsigned Mask3Reg = RegInfo.createVirtualRegister(RC);
5082     unsigned Tmp2Reg = RegInfo.createVirtualRegister(RC);
5083     unsigned Tmp4Reg = RegInfo.createVirtualRegister(RC);
5084     unsigned TmpDestReg = RegInfo.createVirtualRegister(RC);
5085     unsigned Ptr1Reg;
5086     unsigned TmpReg = RegInfo.createVirtualRegister(RC);
5087     unsigned ZeroReg = is64bit ? PPC::X0 : PPC::R0;
5088     //  thisMBB:
5089     //   ...
5090     //   fallthrough --> loopMBB
5091     BB->addSuccessor(loop1MBB);
5092 
5093     // The 4-byte load must be aligned, while a char or short may be
5094     // anywhere in the word.  Hence all this nasty bookkeeping code.
5095     //   add ptr1, ptrA, ptrB [copy if ptrA==0]
5096     //   rlwinm shift1, ptr1, 3, 27, 28 [3, 27, 27]
5097     //   xori shift, shift1, 24 [16]
5098     //   rlwinm ptr, ptr1, 0, 0, 29
5099     //   slw newval2, newval, shift
5100     //   slw oldval2, oldval,shift
5101     //   li mask2, 255 [li mask3, 0; ori mask2, mask3, 65535]
5102     //   slw mask, mask2, shift
5103     //   and newval3, newval2, mask
5104     //   and oldval3, oldval2, mask
5105     // loop1MBB:
5106     //   lwarx tmpDest, ptr
5107     //   and tmp, tmpDest, mask
5108     //   cmpw tmp, oldval3
5109     //   bne- midMBB
5110     // loop2MBB:
5111     //   andc tmp2, tmpDest, mask
5112     //   or tmp4, tmp2, newval3
5113     //   stwcx. tmp4, ptr
5114     //   bne- loop1MBB
5115     //   b exitBB
5116     // midMBB:
5117     //   stwcx. tmpDest, ptr
5118     // exitBB:
5119     //   srw dest, tmpDest, shift
5120     if (ptrA != ZeroReg) {
5121       Ptr1Reg = RegInfo.createVirtualRegister(RC);
5122       BuildMI(BB, dl, TII->get(is64bit ? PPC::ADD8 : PPC::ADD4), Ptr1Reg)
5123         .addReg(ptrA).addReg(ptrB);
5124     } else {
5125       Ptr1Reg = ptrB;
5126     }
5127     BuildMI(BB, dl, TII->get(PPC::RLWINM), Shift1Reg).addReg(Ptr1Reg)
5128         .addImm(3).addImm(27).addImm(is8bit ? 28 : 27);
5129     BuildMI(BB, dl, TII->get(is64bit ? PPC::XORI8 : PPC::XORI), ShiftReg)
5130         .addReg(Shift1Reg).addImm(is8bit ? 24 : 16);
5131     if (is64bit)
5132       BuildMI(BB, dl, TII->get(PPC::RLDICR), PtrReg)
5133         .addReg(Ptr1Reg).addImm(0).addImm(61);
5134     else
5135       BuildMI(BB, dl, TII->get(PPC::RLWINM), PtrReg)
5136         .addReg(Ptr1Reg).addImm(0).addImm(0).addImm(29);
5137     BuildMI(BB, dl, TII->get(PPC::SLW), NewVal2Reg)
5138         .addReg(newval).addReg(ShiftReg);
5139     BuildMI(BB, dl, TII->get(PPC::SLW), OldVal2Reg)
5140         .addReg(oldval).addReg(ShiftReg);
5141     if (is8bit)
5142       BuildMI(BB, dl, TII->get(PPC::LI), Mask2Reg).addImm(255);
5143     else {
5144       BuildMI(BB, dl, TII->get(PPC::LI), Mask3Reg).addImm(0);
5145       BuildMI(BB, dl, TII->get(PPC::ORI), Mask2Reg)
5146         .addReg(Mask3Reg).addImm(65535);
5147     }
5148     BuildMI(BB, dl, TII->get(PPC::SLW), MaskReg)
5149         .addReg(Mask2Reg).addReg(ShiftReg);
5150     BuildMI(BB, dl, TII->get(PPC::AND), NewVal3Reg)
5151         .addReg(NewVal2Reg).addReg(MaskReg);
5152     BuildMI(BB, dl, TII->get(PPC::AND), OldVal3Reg)
5153         .addReg(OldVal2Reg).addReg(MaskReg);
5154 
5155     BB = loop1MBB;
5156     BuildMI(BB, dl, TII->get(PPC::LWARX), TmpDestReg)
5157         .addReg(ZeroReg).addReg(PtrReg);
5158     BuildMI(BB, dl, TII->get(PPC::AND),TmpReg)
5159         .addReg(TmpDestReg).addReg(MaskReg);
5160     BuildMI(BB, dl, TII->get(PPC::CMPW), PPC::CR0)
5161         .addReg(TmpReg).addReg(OldVal3Reg);
5162     BuildMI(BB, dl, TII->get(PPC::BCC))
5163         .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(midMBB);
5164     BB->addSuccessor(loop2MBB);
5165     BB->addSuccessor(midMBB);
5166 
5167     BB = loop2MBB;
5168     BuildMI(BB, dl, TII->get(PPC::ANDC),Tmp2Reg)
5169         .addReg(TmpDestReg).addReg(MaskReg);
5170     BuildMI(BB, dl, TII->get(PPC::OR),Tmp4Reg)
5171         .addReg(Tmp2Reg).addReg(NewVal3Reg);
5172     BuildMI(BB, dl, TII->get(PPC::STWCX)).addReg(Tmp4Reg)
5173         .addReg(ZeroReg).addReg(PtrReg);
5174     BuildMI(BB, dl, TII->get(PPC::BCC))
5175       .addImm(PPC::PRED_NE).addReg(PPC::CR0).addMBB(loop1MBB);
5176     BuildMI(BB, dl, TII->get(PPC::B)).addMBB(exitMBB);
5177     BB->addSuccessor(loop1MBB);
5178     BB->addSuccessor(exitMBB);
5179 
5180     BB = midMBB;
5181     BuildMI(BB, dl, TII->get(PPC::STWCX)).addReg(TmpDestReg)
5182       .addReg(ZeroReg).addReg(PtrReg);
5183     BB->addSuccessor(exitMBB);
5184 
5185     //  exitMBB:
5186     //   ...
5187     BB = exitMBB;
5188     BuildMI(*BB, BB->begin(), dl, TII->get(PPC::SRW),dest).addReg(TmpReg)
5189       .addReg(ShiftReg);
5190   } else {
5191     llvm_unreachable("Unexpected instr type to insert");
5192   }
5193 
5194   MI->eraseFromParent();   // The pseudo instruction is gone now.
5195   return BB;
5196 }
5197 
5198 //===----------------------------------------------------------------------===//
5199 // Target Optimization Hooks
5200 //===----------------------------------------------------------------------===//
5201 
PerformDAGCombine(SDNode * N,DAGCombinerInfo & DCI) const5202 SDValue PPCTargetLowering::PerformDAGCombine(SDNode *N,
5203                                              DAGCombinerInfo &DCI) const {
5204   const TargetMachine &TM = getTargetMachine();
5205   SelectionDAG &DAG = DCI.DAG;
5206   DebugLoc dl = N->getDebugLoc();
5207   switch (N->getOpcode()) {
5208   default: break;
5209   case PPCISD::SHL:
5210     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(0))) {
5211       if (C->isNullValue())   // 0 << V -> 0.
5212         return N->getOperand(0);
5213     }
5214     break;
5215   case PPCISD::SRL:
5216     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(0))) {
5217       if (C->isNullValue())   // 0 >>u V -> 0.
5218         return N->getOperand(0);
5219     }
5220     break;
5221   case PPCISD::SRA:
5222     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(0))) {
5223       if (C->isNullValue() ||   //  0 >>s V -> 0.
5224           C->isAllOnesValue())    // -1 >>s V -> -1.
5225         return N->getOperand(0);
5226     }
5227     break;
5228 
5229   case ISD::SINT_TO_FP:
5230     if (TM.getSubtarget<PPCSubtarget>().has64BitSupport()) {
5231       if (N->getOperand(0).getOpcode() == ISD::FP_TO_SINT) {
5232         // Turn (sint_to_fp (fp_to_sint X)) -> fctidz/fcfid without load/stores.
5233         // We allow the src/dst to be either f32/f64, but the intermediate
5234         // type must be i64.
5235         if (N->getOperand(0).getValueType() == MVT::i64 &&
5236             N->getOperand(0).getOperand(0).getValueType() != MVT::ppcf128) {
5237           SDValue Val = N->getOperand(0).getOperand(0);
5238           if (Val.getValueType() == MVT::f32) {
5239             Val = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Val);
5240             DCI.AddToWorklist(Val.getNode());
5241           }
5242 
5243           Val = DAG.getNode(PPCISD::FCTIDZ, dl, MVT::f64, Val);
5244           DCI.AddToWorklist(Val.getNode());
5245           Val = DAG.getNode(PPCISD::FCFID, dl, MVT::f64, Val);
5246           DCI.AddToWorklist(Val.getNode());
5247           if (N->getValueType(0) == MVT::f32) {
5248             Val = DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Val,
5249                               DAG.getIntPtrConstant(0));
5250             DCI.AddToWorklist(Val.getNode());
5251           }
5252           return Val;
5253         } else if (N->getOperand(0).getValueType() == MVT::i32) {
5254           // If the intermediate type is i32, we can avoid the load/store here
5255           // too.
5256         }
5257       }
5258     }
5259     break;
5260   case ISD::STORE:
5261     // Turn STORE (FP_TO_SINT F) -> STFIWX(FCTIWZ(F)).
5262     if (TM.getSubtarget<PPCSubtarget>().hasSTFIWX() &&
5263         !cast<StoreSDNode>(N)->isTruncatingStore() &&
5264         N->getOperand(1).getOpcode() == ISD::FP_TO_SINT &&
5265         N->getOperand(1).getValueType() == MVT::i32 &&
5266         N->getOperand(1).getOperand(0).getValueType() != MVT::ppcf128) {
5267       SDValue Val = N->getOperand(1).getOperand(0);
5268       if (Val.getValueType() == MVT::f32) {
5269         Val = DAG.getNode(ISD::FP_EXTEND, dl, MVT::f64, Val);
5270         DCI.AddToWorklist(Val.getNode());
5271       }
5272       Val = DAG.getNode(PPCISD::FCTIWZ, dl, MVT::f64, Val);
5273       DCI.AddToWorklist(Val.getNode());
5274 
5275       Val = DAG.getNode(PPCISD::STFIWX, dl, MVT::Other, N->getOperand(0), Val,
5276                         N->getOperand(2), N->getOperand(3));
5277       DCI.AddToWorklist(Val.getNode());
5278       return Val;
5279     }
5280 
5281     // Turn STORE (BSWAP) -> sthbrx/stwbrx.
5282     if (cast<StoreSDNode>(N)->isUnindexed() &&
5283         N->getOperand(1).getOpcode() == ISD::BSWAP &&
5284         N->getOperand(1).getNode()->hasOneUse() &&
5285         (N->getOperand(1).getValueType() == MVT::i32 ||
5286          N->getOperand(1).getValueType() == MVT::i16)) {
5287       SDValue BSwapOp = N->getOperand(1).getOperand(0);
5288       // Do an any-extend to 32-bits if this is a half-word input.
5289       if (BSwapOp.getValueType() == MVT::i16)
5290         BSwapOp = DAG.getNode(ISD::ANY_EXTEND, dl, MVT::i32, BSwapOp);
5291 
5292       SDValue Ops[] = {
5293         N->getOperand(0), BSwapOp, N->getOperand(2),
5294         DAG.getValueType(N->getOperand(1).getValueType())
5295       };
5296       return
5297         DAG.getMemIntrinsicNode(PPCISD::STBRX, dl, DAG.getVTList(MVT::Other),
5298                                 Ops, array_lengthof(Ops),
5299                                 cast<StoreSDNode>(N)->getMemoryVT(),
5300                                 cast<StoreSDNode>(N)->getMemOperand());
5301     }
5302     break;
5303   case ISD::BSWAP:
5304     // Turn BSWAP (LOAD) -> lhbrx/lwbrx.
5305     if (ISD::isNON_EXTLoad(N->getOperand(0).getNode()) &&
5306         N->getOperand(0).hasOneUse() &&
5307         (N->getValueType(0) == MVT::i32 || N->getValueType(0) == MVT::i16)) {
5308       SDValue Load = N->getOperand(0);
5309       LoadSDNode *LD = cast<LoadSDNode>(Load);
5310       // Create the byte-swapping load.
5311       SDValue Ops[] = {
5312         LD->getChain(),    // Chain
5313         LD->getBasePtr(),  // Ptr
5314         DAG.getValueType(N->getValueType(0)) // VT
5315       };
5316       SDValue BSLoad =
5317         DAG.getMemIntrinsicNode(PPCISD::LBRX, dl,
5318                                 DAG.getVTList(MVT::i32, MVT::Other), Ops, 3,
5319                                 LD->getMemoryVT(), LD->getMemOperand());
5320 
5321       // If this is an i16 load, insert the truncate.
5322       SDValue ResVal = BSLoad;
5323       if (N->getValueType(0) == MVT::i16)
5324         ResVal = DAG.getNode(ISD::TRUNCATE, dl, MVT::i16, BSLoad);
5325 
5326       // First, combine the bswap away.  This makes the value produced by the
5327       // load dead.
5328       DCI.CombineTo(N, ResVal);
5329 
5330       // Next, combine the load away, we give it a bogus result value but a real
5331       // chain result.  The result value is dead because the bswap is dead.
5332       DCI.CombineTo(Load.getNode(), ResVal, BSLoad.getValue(1));
5333 
5334       // Return N so it doesn't get rechecked!
5335       return SDValue(N, 0);
5336     }
5337 
5338     break;
5339   case PPCISD::VCMP: {
5340     // If a VCMPo node already exists with exactly the same operands as this
5341     // node, use its result instead of this node (VCMPo computes both a CR6 and
5342     // a normal output).
5343     //
5344     if (!N->getOperand(0).hasOneUse() &&
5345         !N->getOperand(1).hasOneUse() &&
5346         !N->getOperand(2).hasOneUse()) {
5347 
5348       // Scan all of the users of the LHS, looking for VCMPo's that match.
5349       SDNode *VCMPoNode = 0;
5350 
5351       SDNode *LHSN = N->getOperand(0).getNode();
5352       for (SDNode::use_iterator UI = LHSN->use_begin(), E = LHSN->use_end();
5353            UI != E; ++UI)
5354         if (UI->getOpcode() == PPCISD::VCMPo &&
5355             UI->getOperand(1) == N->getOperand(1) &&
5356             UI->getOperand(2) == N->getOperand(2) &&
5357             UI->getOperand(0) == N->getOperand(0)) {
5358           VCMPoNode = *UI;
5359           break;
5360         }
5361 
5362       // If there is no VCMPo node, or if the flag value has a single use, don't
5363       // transform this.
5364       if (!VCMPoNode || VCMPoNode->hasNUsesOfValue(0, 1))
5365         break;
5366 
5367       // Look at the (necessarily single) use of the flag value.  If it has a
5368       // chain, this transformation is more complex.  Note that multiple things
5369       // could use the value result, which we should ignore.
5370       SDNode *FlagUser = 0;
5371       for (SDNode::use_iterator UI = VCMPoNode->use_begin();
5372            FlagUser == 0; ++UI) {
5373         assert(UI != VCMPoNode->use_end() && "Didn't find user!");
5374         SDNode *User = *UI;
5375         for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) {
5376           if (User->getOperand(i) == SDValue(VCMPoNode, 1)) {
5377             FlagUser = User;
5378             break;
5379           }
5380         }
5381       }
5382 
5383       // If the user is a MFCR instruction, we know this is safe.  Otherwise we
5384       // give up for right now.
5385       if (FlagUser->getOpcode() == PPCISD::MFCR)
5386         return SDValue(VCMPoNode, 0);
5387     }
5388     break;
5389   }
5390   case ISD::BR_CC: {
5391     // If this is a branch on an altivec predicate comparison, lower this so
5392     // that we don't have to do a MFCR: instead, branch directly on CR6.  This
5393     // lowering is done pre-legalize, because the legalizer lowers the predicate
5394     // compare down to code that is difficult to reassemble.
5395     ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(1))->get();
5396     SDValue LHS = N->getOperand(2), RHS = N->getOperand(3);
5397     int CompareOpc;
5398     bool isDot;
5399 
5400     if (LHS.getOpcode() == ISD::INTRINSIC_WO_CHAIN &&
5401         isa<ConstantSDNode>(RHS) && (CC == ISD::SETEQ || CC == ISD::SETNE) &&
5402         getAltivecCompareInfo(LHS, CompareOpc, isDot)) {
5403       assert(isDot && "Can't compare against a vector result!");
5404 
5405       // If this is a comparison against something other than 0/1, then we know
5406       // that the condition is never/always true.
5407       unsigned Val = cast<ConstantSDNode>(RHS)->getZExtValue();
5408       if (Val != 0 && Val != 1) {
5409         if (CC == ISD::SETEQ)      // Cond never true, remove branch.
5410           return N->getOperand(0);
5411         // Always !=, turn it into an unconditional branch.
5412         return DAG.getNode(ISD::BR, dl, MVT::Other,
5413                            N->getOperand(0), N->getOperand(4));
5414       }
5415 
5416       bool BranchOnWhenPredTrue = (CC == ISD::SETEQ) ^ (Val == 0);
5417 
5418       // Create the PPCISD altivec 'dot' comparison node.
5419       std::vector<EVT> VTs;
5420       SDValue Ops[] = {
5421         LHS.getOperand(2),  // LHS of compare
5422         LHS.getOperand(3),  // RHS of compare
5423         DAG.getConstant(CompareOpc, MVT::i32)
5424       };
5425       VTs.push_back(LHS.getOperand(2).getValueType());
5426       VTs.push_back(MVT::Glue);
5427       SDValue CompNode = DAG.getNode(PPCISD::VCMPo, dl, VTs, Ops, 3);
5428 
5429       // Unpack the result based on how the target uses it.
5430       PPC::Predicate CompOpc;
5431       switch (cast<ConstantSDNode>(LHS.getOperand(1))->getZExtValue()) {
5432       default:  // Can't happen, don't crash on invalid number though.
5433       case 0:   // Branch on the value of the EQ bit of CR6.
5434         CompOpc = BranchOnWhenPredTrue ? PPC::PRED_EQ : PPC::PRED_NE;
5435         break;
5436       case 1:   // Branch on the inverted value of the EQ bit of CR6.
5437         CompOpc = BranchOnWhenPredTrue ? PPC::PRED_NE : PPC::PRED_EQ;
5438         break;
5439       case 2:   // Branch on the value of the LT bit of CR6.
5440         CompOpc = BranchOnWhenPredTrue ? PPC::PRED_LT : PPC::PRED_GE;
5441         break;
5442       case 3:   // Branch on the inverted value of the LT bit of CR6.
5443         CompOpc = BranchOnWhenPredTrue ? PPC::PRED_GE : PPC::PRED_LT;
5444         break;
5445       }
5446 
5447       return DAG.getNode(PPCISD::COND_BRANCH, dl, MVT::Other, N->getOperand(0),
5448                          DAG.getConstant(CompOpc, MVT::i32),
5449                          DAG.getRegister(PPC::CR6, MVT::i32),
5450                          N->getOperand(4), CompNode.getValue(1));
5451     }
5452     break;
5453   }
5454   }
5455 
5456   return SDValue();
5457 }
5458 
5459 //===----------------------------------------------------------------------===//
5460 // Inline Assembly Support
5461 //===----------------------------------------------------------------------===//
5462 
computeMaskedBitsForTargetNode(const SDValue Op,const APInt & Mask,APInt & KnownZero,APInt & KnownOne,const SelectionDAG & DAG,unsigned Depth) const5463 void PPCTargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
5464                                                        const APInt &Mask,
5465                                                        APInt &KnownZero,
5466                                                        APInt &KnownOne,
5467                                                        const SelectionDAG &DAG,
5468                                                        unsigned Depth) const {
5469   KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);
5470   switch (Op.getOpcode()) {
5471   default: break;
5472   case PPCISD::LBRX: {
5473     // lhbrx is known to have the top bits cleared out.
5474     if (cast<VTSDNode>(Op.getOperand(2))->getVT() == MVT::i16)
5475       KnownZero = 0xFFFF0000;
5476     break;
5477   }
5478   case ISD::INTRINSIC_WO_CHAIN: {
5479     switch (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue()) {
5480     default: break;
5481     case Intrinsic::ppc_altivec_vcmpbfp_p:
5482     case Intrinsic::ppc_altivec_vcmpeqfp_p:
5483     case Intrinsic::ppc_altivec_vcmpequb_p:
5484     case Intrinsic::ppc_altivec_vcmpequh_p:
5485     case Intrinsic::ppc_altivec_vcmpequw_p:
5486     case Intrinsic::ppc_altivec_vcmpgefp_p:
5487     case Intrinsic::ppc_altivec_vcmpgtfp_p:
5488     case Intrinsic::ppc_altivec_vcmpgtsb_p:
5489     case Intrinsic::ppc_altivec_vcmpgtsh_p:
5490     case Intrinsic::ppc_altivec_vcmpgtsw_p:
5491     case Intrinsic::ppc_altivec_vcmpgtub_p:
5492     case Intrinsic::ppc_altivec_vcmpgtuh_p:
5493     case Intrinsic::ppc_altivec_vcmpgtuw_p:
5494       KnownZero = ~1U;  // All bits but the low one are known to be zero.
5495       break;
5496     }
5497   }
5498   }
5499 }
5500 
5501 
5502 /// getConstraintType - Given a constraint, return the type of
5503 /// constraint it is for this target.
5504 PPCTargetLowering::ConstraintType
getConstraintType(const std::string & Constraint) const5505 PPCTargetLowering::getConstraintType(const std::string &Constraint) const {
5506   if (Constraint.size() == 1) {
5507     switch (Constraint[0]) {
5508     default: break;
5509     case 'b':
5510     case 'r':
5511     case 'f':
5512     case 'v':
5513     case 'y':
5514       return C_RegisterClass;
5515     }
5516   }
5517   return TargetLowering::getConstraintType(Constraint);
5518 }
5519 
5520 /// Examine constraint type and operand type and determine a weight value.
5521 /// This object must already have been set up with the operand type
5522 /// and the current alternative constraint selected.
5523 TargetLowering::ConstraintWeight
getSingleConstraintMatchWeight(AsmOperandInfo & info,const char * constraint) const5524 PPCTargetLowering::getSingleConstraintMatchWeight(
5525     AsmOperandInfo &info, const char *constraint) const {
5526   ConstraintWeight weight = CW_Invalid;
5527   Value *CallOperandVal = info.CallOperandVal;
5528     // If we don't have a value, we can't do a match,
5529     // but allow it at the lowest weight.
5530   if (CallOperandVal == NULL)
5531     return CW_Default;
5532   Type *type = CallOperandVal->getType();
5533   // Look at the constraint type.
5534   switch (*constraint) {
5535   default:
5536     weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
5537     break;
5538   case 'b':
5539     if (type->isIntegerTy())
5540       weight = CW_Register;
5541     break;
5542   case 'f':
5543     if (type->isFloatTy())
5544       weight = CW_Register;
5545     break;
5546   case 'd':
5547     if (type->isDoubleTy())
5548       weight = CW_Register;
5549     break;
5550   case 'v':
5551     if (type->isVectorTy())
5552       weight = CW_Register;
5553     break;
5554   case 'y':
5555     weight = CW_Register;
5556     break;
5557   }
5558   return weight;
5559 }
5560 
5561 std::pair<unsigned, const TargetRegisterClass*>
getRegForInlineAsmConstraint(const std::string & Constraint,EVT VT) const5562 PPCTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
5563                                                 EVT VT) const {
5564   if (Constraint.size() == 1) {
5565     // GCC RS6000 Constraint Letters
5566     switch (Constraint[0]) {
5567     case 'b':   // R1-R31
5568     case 'r':   // R0-R31
5569       if (VT == MVT::i64 && PPCSubTarget.isPPC64())
5570         return std::make_pair(0U, PPC::G8RCRegisterClass);
5571       return std::make_pair(0U, PPC::GPRCRegisterClass);
5572     case 'f':
5573       if (VT == MVT::f32)
5574         return std::make_pair(0U, PPC::F4RCRegisterClass);
5575       else if (VT == MVT::f64)
5576         return std::make_pair(0U, PPC::F8RCRegisterClass);
5577       break;
5578     case 'v':
5579       return std::make_pair(0U, PPC::VRRCRegisterClass);
5580     case 'y':   // crrc
5581       return std::make_pair(0U, PPC::CRRCRegisterClass);
5582     }
5583   }
5584 
5585   return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
5586 }
5587 
5588 
5589 /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
5590 /// vector.  If it is invalid, don't add anything to Ops.
LowerAsmOperandForConstraint(SDValue Op,std::string & Constraint,std::vector<SDValue> & Ops,SelectionDAG & DAG) const5591 void PPCTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
5592                                                      std::string &Constraint,
5593                                                      std::vector<SDValue>&Ops,
5594                                                      SelectionDAG &DAG) const {
5595   SDValue Result(0,0);
5596 
5597   // Only support length 1 constraints.
5598   if (Constraint.length() > 1) return;
5599 
5600   char Letter = Constraint[0];
5601   switch (Letter) {
5602   default: break;
5603   case 'I':
5604   case 'J':
5605   case 'K':
5606   case 'L':
5607   case 'M':
5608   case 'N':
5609   case 'O':
5610   case 'P': {
5611     ConstantSDNode *CST = dyn_cast<ConstantSDNode>(Op);
5612     if (!CST) return; // Must be an immediate to match.
5613     unsigned Value = CST->getZExtValue();
5614     switch (Letter) {
5615     default: llvm_unreachable("Unknown constraint letter!");
5616     case 'I':  // "I" is a signed 16-bit constant.
5617       if ((short)Value == (int)Value)
5618         Result = DAG.getTargetConstant(Value, Op.getValueType());
5619       break;
5620     case 'J':  // "J" is a constant with only the high-order 16 bits nonzero.
5621     case 'L':  // "L" is a signed 16-bit constant shifted left 16 bits.
5622       if ((short)Value == 0)
5623         Result = DAG.getTargetConstant(Value, Op.getValueType());
5624       break;
5625     case 'K':  // "K" is a constant with only the low-order 16 bits nonzero.
5626       if ((Value >> 16) == 0)
5627         Result = DAG.getTargetConstant(Value, Op.getValueType());
5628       break;
5629     case 'M':  // "M" is a constant that is greater than 31.
5630       if (Value > 31)
5631         Result = DAG.getTargetConstant(Value, Op.getValueType());
5632       break;
5633     case 'N':  // "N" is a positive constant that is an exact power of two.
5634       if ((int)Value > 0 && isPowerOf2_32(Value))
5635         Result = DAG.getTargetConstant(Value, Op.getValueType());
5636       break;
5637     case 'O':  // "O" is the constant zero.
5638       if (Value == 0)
5639         Result = DAG.getTargetConstant(Value, Op.getValueType());
5640       break;
5641     case 'P':  // "P" is a constant whose negation is a signed 16-bit constant.
5642       if ((short)-Value == (int)-Value)
5643         Result = DAG.getTargetConstant(Value, Op.getValueType());
5644       break;
5645     }
5646     break;
5647   }
5648   }
5649 
5650   if (Result.getNode()) {
5651     Ops.push_back(Result);
5652     return;
5653   }
5654 
5655   // Handle standard constraint letters.
5656   TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
5657 }
5658 
5659 // isLegalAddressingMode - Return true if the addressing mode represented
5660 // by AM is legal for this target, for a load/store of the specified type.
isLegalAddressingMode(const AddrMode & AM,Type * Ty) const5661 bool PPCTargetLowering::isLegalAddressingMode(const AddrMode &AM,
5662                                               Type *Ty) const {
5663   // FIXME: PPC does not allow r+i addressing modes for vectors!
5664 
5665   // PPC allows a sign-extended 16-bit immediate field.
5666   if (AM.BaseOffs <= -(1LL << 16) || AM.BaseOffs >= (1LL << 16)-1)
5667     return false;
5668 
5669   // No global is ever allowed as a base.
5670   if (AM.BaseGV)
5671     return false;
5672 
5673   // PPC only support r+r,
5674   switch (AM.Scale) {
5675   case 0:  // "r+i" or just "i", depending on HasBaseReg.
5676     break;
5677   case 1:
5678     if (AM.HasBaseReg && AM.BaseOffs)  // "r+r+i" is not allowed.
5679       return false;
5680     // Otherwise we have r+r or r+i.
5681     break;
5682   case 2:
5683     if (AM.HasBaseReg || AM.BaseOffs)  // 2*r+r  or  2*r+i is not allowed.
5684       return false;
5685     // Allow 2*r as r+r.
5686     break;
5687   default:
5688     // No other scales are supported.
5689     return false;
5690   }
5691 
5692   return true;
5693 }
5694 
5695 /// isLegalAddressImmediate - Return true if the integer value can be used
5696 /// as the offset of the target addressing mode for load / store of the
5697 /// given type.
isLegalAddressImmediate(int64_t V,Type * Ty) const5698 bool PPCTargetLowering::isLegalAddressImmediate(int64_t V,Type *Ty) const{
5699   // PPC allows a sign-extended 16-bit immediate field.
5700   return (V > -(1 << 16) && V < (1 << 16)-1);
5701 }
5702 
isLegalAddressImmediate(llvm::GlobalValue * GV) const5703 bool PPCTargetLowering::isLegalAddressImmediate(llvm::GlobalValue* GV) const {
5704   return false;
5705 }
5706 
LowerRETURNADDR(SDValue Op,SelectionDAG & DAG) const5707 SDValue PPCTargetLowering::LowerRETURNADDR(SDValue Op,
5708                                            SelectionDAG &DAG) const {
5709   MachineFunction &MF = DAG.getMachineFunction();
5710   MachineFrameInfo *MFI = MF.getFrameInfo();
5711   MFI->setReturnAddressIsTaken(true);
5712 
5713   DebugLoc dl = Op.getDebugLoc();
5714   unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
5715 
5716   // Make sure the function does not optimize away the store of the RA to
5717   // the stack.
5718   PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
5719   FuncInfo->setLRStoreRequired();
5720   bool isPPC64 = PPCSubTarget.isPPC64();
5721   bool isDarwinABI = PPCSubTarget.isDarwinABI();
5722 
5723   if (Depth > 0) {
5724     SDValue FrameAddr = LowerFRAMEADDR(Op, DAG);
5725     SDValue Offset =
5726 
5727       DAG.getConstant(PPCFrameLowering::getReturnSaveOffset(isPPC64, isDarwinABI),
5728                       isPPC64? MVT::i64 : MVT::i32);
5729     return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
5730                        DAG.getNode(ISD::ADD, dl, getPointerTy(),
5731                                    FrameAddr, Offset),
5732                        MachinePointerInfo(), false, false, 0);
5733   }
5734 
5735   // Just load the return address off the stack.
5736   SDValue RetAddrFI = getReturnAddrFrameIndex(DAG);
5737   return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
5738                      RetAddrFI, MachinePointerInfo(), false, false, 0);
5739 }
5740 
LowerFRAMEADDR(SDValue Op,SelectionDAG & DAG) const5741 SDValue PPCTargetLowering::LowerFRAMEADDR(SDValue Op,
5742                                           SelectionDAG &DAG) const {
5743   DebugLoc dl = Op.getDebugLoc();
5744   unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
5745 
5746   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
5747   bool isPPC64 = PtrVT == MVT::i64;
5748 
5749   MachineFunction &MF = DAG.getMachineFunction();
5750   MachineFrameInfo *MFI = MF.getFrameInfo();
5751   MFI->setFrameAddressIsTaken(true);
5752   bool is31 = (DisableFramePointerElim(MF) || MFI->hasVarSizedObjects()) &&
5753                   MFI->getStackSize() &&
5754                   !MF.getFunction()->hasFnAttr(Attribute::Naked);
5755   unsigned FrameReg = isPPC64 ? (is31 ? PPC::X31 : PPC::X1) :
5756                                 (is31 ? PPC::R31 : PPC::R1);
5757   SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl, FrameReg,
5758                                          PtrVT);
5759   while (Depth--)
5760     FrameAddr = DAG.getLoad(Op.getValueType(), dl, DAG.getEntryNode(),
5761                             FrameAddr, MachinePointerInfo(), false, false, 0);
5762   return FrameAddr;
5763 }
5764 
5765 bool
isOffsetFoldingLegal(const GlobalAddressSDNode * GA) const5766 PPCTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
5767   // The PowerPC target isn't yet aware of offsets.
5768   return false;
5769 }
5770 
5771 /// getOptimalMemOpType - Returns the target specific optimal type for load
5772 /// and store operations as a result of memset, memcpy, and memmove
5773 /// lowering. If DstAlign is zero that means it's safe to destination
5774 /// alignment can satisfy any constraint. Similarly if SrcAlign is zero it
5775 /// means there isn't a need to check it against alignment requirement,
5776 /// probably because the source does not need to be loaded. If
5777 /// 'NonScalarIntSafe' is true, that means it's safe to return a
5778 /// non-scalar-integer type, e.g. empty string source, constant, or loaded
5779 /// from memory. 'MemcpyStrSrc' indicates whether the memcpy source is
5780 /// constant so it does not need to be loaded.
5781 /// It returns EVT::Other if the type should be determined using generic
5782 /// target-independent logic.
getOptimalMemOpType(uint64_t Size,unsigned DstAlign,unsigned SrcAlign,bool NonScalarIntSafe,bool MemcpyStrSrc,MachineFunction & MF) const5783 EVT PPCTargetLowering::getOptimalMemOpType(uint64_t Size,
5784                                            unsigned DstAlign, unsigned SrcAlign,
5785                                            bool NonScalarIntSafe,
5786                                            bool MemcpyStrSrc,
5787                                            MachineFunction &MF) const {
5788   if (this->PPCSubTarget.isPPC64()) {
5789     return MVT::i64;
5790   } else {
5791     return MVT::i32;
5792   }
5793 }
5794