• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- MipsISelLowering.h - Mips DAG Lowering Interface --------*- C++ -*-===//
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 defines the interfaces that Mips uses to lower LLVM code into a
11 // selection DAG.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef MipsISELLOWERING_H
16 #define MipsISELLOWERING_H
17 
18 #include "Mips.h"
19 #include "MipsSubtarget.h"
20 #include "llvm/CodeGen/CallingConvLower.h"
21 #include "llvm/CodeGen/SelectionDAG.h"
22 #include "llvm/IR/Function.h"
23 #include "llvm/Target/TargetLowering.h"
24 #include <deque>
25 #include <string>
26 
27 namespace llvm {
28   namespace MipsISD {
29     enum NodeType {
30       // Start the numbering from where ISD NodeType finishes.
31       FIRST_NUMBER = ISD::BUILTIN_OP_END,
32 
33       // Jump and link (call)
34       JmpLink,
35 
36       // Tail call
37       TailCall,
38 
39       // Get the Higher 16 bits from a 32-bit immediate
40       // No relation with Mips Hi register
41       Hi,
42 
43       // Get the Lower 16 bits from a 32-bit immediate
44       // No relation with Mips Lo register
45       Lo,
46 
47       // Handle gp_rel (small data/bss sections) relocation.
48       GPRel,
49 
50       // Thread Pointer
51       ThreadPointer,
52 
53       // Floating Point Branch Conditional
54       FPBrcond,
55 
56       // Floating Point Compare
57       FPCmp,
58 
59       // Floating Point Conditional Moves
60       CMovFP_T,
61       CMovFP_F,
62 
63       // Floating Point Rounding
64       FPRound,
65 
66       // Return
67       Ret,
68 
69       EH_RETURN,
70 
71       // MAdd/Sub nodes
72       MAdd,
73       MAddu,
74       MSub,
75       MSubu,
76 
77       // DivRem(u)
78       DivRem,
79       DivRemU,
80 
81       BuildPairF64,
82       ExtractElementF64,
83 
84       Wrapper,
85 
86       DynAlloc,
87 
88       Sync,
89 
90       Ext,
91       Ins,
92 
93       // EXTR.W instrinsic nodes.
94       EXTP,
95       EXTPDP,
96       EXTR_S_H,
97       EXTR_W,
98       EXTR_R_W,
99       EXTR_RS_W,
100       SHILO,
101       MTHLIP,
102 
103       // DPA.W intrinsic nodes.
104       MULSAQ_S_W_PH,
105       MAQ_S_W_PHL,
106       MAQ_S_W_PHR,
107       MAQ_SA_W_PHL,
108       MAQ_SA_W_PHR,
109       DPAU_H_QBL,
110       DPAU_H_QBR,
111       DPSU_H_QBL,
112       DPSU_H_QBR,
113       DPAQ_S_W_PH,
114       DPSQ_S_W_PH,
115       DPAQ_SA_L_W,
116       DPSQ_SA_L_W,
117       DPA_W_PH,
118       DPS_W_PH,
119       DPAQX_S_W_PH,
120       DPAQX_SA_W_PH,
121       DPAX_W_PH,
122       DPSX_W_PH,
123       DPSQX_S_W_PH,
124       DPSQX_SA_W_PH,
125       MULSA_W_PH,
126 
127       MULT,
128       MULTU,
129       MADD_DSP,
130       MADDU_DSP,
131       MSUB_DSP,
132       MSUBU_DSP,
133 
134       // Load/Store Left/Right nodes.
135       LWL = ISD::FIRST_TARGET_MEMORY_OPCODE,
136       LWR,
137       SWL,
138       SWR,
139       LDL,
140       LDR,
141       SDL,
142       SDR
143     };
144   }
145 
146   //===--------------------------------------------------------------------===//
147   // TargetLowering Implementation
148   //===--------------------------------------------------------------------===//
149   class MipsFunctionInfo;
150 
151   class MipsTargetLowering : public TargetLowering  {
152   public:
153     explicit MipsTargetLowering(MipsTargetMachine &TM);
154 
155     static const MipsTargetLowering *create(MipsTargetMachine &TM);
156 
getScalarShiftAmountTy(EVT LHSTy)157     virtual MVT getScalarShiftAmountTy(EVT LHSTy) const { return MVT::i32; }
158 
159     virtual void LowerOperationWrapper(SDNode *N,
160                                        SmallVectorImpl<SDValue> &Results,
161                                        SelectionDAG &DAG) const;
162 
163     /// LowerOperation - Provide custom lowering hooks for some operations.
164     virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const;
165 
166     /// ReplaceNodeResults - Replace the results of node with an illegal result
167     /// type with new values built out of custom code.
168     ///
169     virtual void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
170                                     SelectionDAG &DAG) const;
171 
172     /// getTargetNodeName - This method returns the name of a target specific
173     //  DAG node.
174     virtual const char *getTargetNodeName(unsigned Opcode) const;
175 
176     /// getSetCCResultType - get the ISD::SETCC result ValueType
177     EVT getSetCCResultType(EVT VT) const;
178 
179     virtual SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
180 
181     virtual MachineBasicBlock *
182     EmitInstrWithCustomInserter(MachineInstr *MI, MachineBasicBlock *MBB) const;
183 
184     struct LTStr {
operatorLTStr185       bool operator()(const char *S1, const char *S2) const {
186         return strcmp(S1, S2) < 0;
187       }
188     };
189 
190   protected:
191     SDValue getGlobalReg(SelectionDAG &DAG, EVT Ty) const;
192 
193     SDValue getAddrLocal(SDValue Op, SelectionDAG &DAG, bool HasMips64) const;
194 
195     SDValue getAddrGlobal(SDValue Op, SelectionDAG &DAG, unsigned Flag) const;
196 
197     SDValue getAddrGlobalLargeGOT(SDValue Op, SelectionDAG &DAG,
198                                   unsigned HiFlag, unsigned LoFlag) const;
199 
200     /// This function fills Ops, which is the list of operands that will later
201     /// be used when a function call node is created. It also generates
202     /// copyToReg nodes to set up argument registers.
203     virtual void
204     getOpndList(SmallVectorImpl<SDValue> &Ops,
205                 std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
206                 bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
207                 CallLoweringInfo &CLI, SDValue Callee, SDValue Chain) const;
208 
209     /// ByValArgInfo - Byval argument information.
210     struct ByValArgInfo {
211       unsigned FirstIdx; // Index of the first register used.
212       unsigned NumRegs;  // Number of registers used for this argument.
213       unsigned Address;  // Offset of the stack area used to pass this argument.
214 
ByValArgInfoByValArgInfo215       ByValArgInfo() : FirstIdx(0), NumRegs(0), Address(0) {}
216     };
217 
218     /// MipsCC - This class provides methods used to analyze formal and call
219     /// arguments and inquire about calling convention information.
220     class MipsCC {
221     public:
222       MipsCC(CallingConv::ID CallConv, bool IsO32, CCState &Info);
223 
224       void analyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
225                                bool IsVarArg, bool IsSoftFloat,
226                                const SDNode *CallNode,
227                                std::vector<ArgListEntry> &FuncArgs);
228       void analyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
229                                   bool IsSoftFloat,
230                                   Function::const_arg_iterator FuncArg);
231 
232       void analyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
233                              bool IsSoftFloat, const SDNode *CallNode,
234                              const Type *RetTy) const;
235 
236       void analyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
237                          bool IsSoftFloat, const Type *RetTy) const;
238 
getCCInfo()239       const CCState &getCCInfo() const { return CCInfo; }
240 
241       /// hasByValArg - Returns true if function has byval arguments.
hasByValArg()242       bool hasByValArg() const { return !ByValArgs.empty(); }
243 
244       /// regSize - Size (in number of bits) of integer registers.
regSize()245       unsigned regSize() const { return IsO32 ? 4 : 8; }
246 
247       /// numIntArgRegs - Number of integer registers available for calls.
248       unsigned numIntArgRegs() const;
249 
250       /// reservedArgArea - The size of the area the caller reserves for
251       /// register arguments. This is 16-byte if ABI is O32.
252       unsigned reservedArgArea() const;
253 
254       /// Return pointer to array of integer argument registers.
255       const uint16_t *intArgRegs() const;
256 
257       typedef SmallVector<ByValArgInfo, 2>::const_iterator byval_iterator;
byval_begin()258       byval_iterator byval_begin() const { return ByValArgs.begin(); }
byval_end()259       byval_iterator byval_end() const { return ByValArgs.end(); }
260 
261     private:
262       void handleByValArg(unsigned ValNo, MVT ValVT, MVT LocVT,
263                           CCValAssign::LocInfo LocInfo,
264                           ISD::ArgFlagsTy ArgFlags);
265 
266       /// useRegsForByval - Returns true if the calling convention allows the
267       /// use of registers to pass byval arguments.
useRegsForByval()268       bool useRegsForByval() const { return CallConv != CallingConv::Fast; }
269 
270       /// Return the function that analyzes fixed argument list functions.
271       llvm::CCAssignFn *fixedArgFn() const;
272 
273       /// Return the function that analyzes variable argument list functions.
274       llvm::CCAssignFn *varArgFn() const;
275 
276       const uint16_t *shadowRegs() const;
277 
278       void allocateRegs(ByValArgInfo &ByVal, unsigned ByValSize,
279                         unsigned Align);
280 
281       /// Return the type of the register which is used to pass an argument or
282       /// return a value. This function returns f64 if the argument is an i64
283       /// value which has been generated as a result of softening an f128 value.
284       /// Otherwise, it just returns VT.
285       MVT getRegVT(MVT VT, const Type *OrigTy, const SDNode *CallNode,
286                    bool IsSoftFloat) const;
287 
288       template<typename Ty>
289       void analyzeReturn(const SmallVectorImpl<Ty> &RetVals, bool IsSoftFloat,
290                          const SDNode *CallNode, const Type *RetTy) const;
291 
292       CCState &CCInfo;
293       CallingConv::ID CallConv;
294       bool IsO32;
295       SmallVector<ByValArgInfo, 2> ByValArgs;
296     };
297 
298     // Subtarget Info
299     const MipsSubtarget *Subtarget;
300 
301     bool HasMips64, IsN64, IsO32;
302 
303   private:
304     // Lower Operand helpers
305     SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
306                             CallingConv::ID CallConv, bool isVarArg,
307                             const SmallVectorImpl<ISD::InputArg> &Ins,
308                             DebugLoc dl, SelectionDAG &DAG,
309                             SmallVectorImpl<SDValue> &InVals,
310                             const SDNode *CallNode, const Type *RetTy) const;
311 
312     // Lower Operand specifics
313     SDValue lowerBR_JT(SDValue Op, SelectionDAG &DAG) const;
314     SDValue lowerBRCOND(SDValue Op, SelectionDAG &DAG) const;
315     SDValue lowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
316     SDValue lowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
317     SDValue lowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
318     SDValue lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
319     SDValue lowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
320     SDValue lowerSELECT(SDValue Op, SelectionDAG &DAG) const;
321     SDValue lowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
322     SDValue lowerSETCC(SDValue Op, SelectionDAG &DAG) const;
323     SDValue lowerVASTART(SDValue Op, SelectionDAG &DAG) const;
324     SDValue lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const;
325     SDValue lowerFABS(SDValue Op, SelectionDAG &DAG) const;
326     SDValue lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
327     SDValue lowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
328     SDValue lowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const;
329     SDValue lowerMEMBARRIER(SDValue Op, SelectionDAG& DAG) const;
330     SDValue lowerATOMIC_FENCE(SDValue Op, SelectionDAG& DAG) const;
331     SDValue lowerShiftLeftParts(SDValue Op, SelectionDAG& DAG) const;
332     SDValue lowerShiftRightParts(SDValue Op, SelectionDAG& DAG,
333                                  bool IsSRA) const;
334     SDValue lowerLOAD(SDValue Op, SelectionDAG &DAG) const;
335     SDValue lowerSTORE(SDValue Op, SelectionDAG &DAG) const;
336     SDValue lowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
337     SDValue lowerINTRINSIC_W_CHAIN(SDValue Op, SelectionDAG &DAG) const;
338     SDValue lowerADD(SDValue Op, SelectionDAG &DAG) const;
339 
340     /// isEligibleForTailCallOptimization - Check whether the call is eligible
341     /// for tail call optimization.
342     virtual bool
343     isEligibleForTailCallOptimization(const MipsCC &MipsCCInfo,
344                                       unsigned NextStackOffset,
345                                       const MipsFunctionInfo& FI) const = 0;
346 
347     /// copyByValArg - Copy argument registers which were used to pass a byval
348     /// argument to the stack. Create a stack frame object for the byval
349     /// argument.
350     void copyByValRegs(SDValue Chain, DebugLoc DL,
351                        std::vector<SDValue> &OutChains, SelectionDAG &DAG,
352                        const ISD::ArgFlagsTy &Flags,
353                        SmallVectorImpl<SDValue> &InVals,
354                        const Argument *FuncArg,
355                        const MipsCC &CC, const ByValArgInfo &ByVal) const;
356 
357     /// passByValArg - Pass a byval argument in registers or on stack.
358     void passByValArg(SDValue Chain, DebugLoc DL,
359                       std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
360                       SmallVector<SDValue, 8> &MemOpChains, SDValue StackPtr,
361                       MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
362                       const MipsCC &CC, const ByValArgInfo &ByVal,
363                       const ISD::ArgFlagsTy &Flags, bool isLittle) const;
364 
365     /// writeVarArgRegs - Write variable function arguments passed in registers
366     /// to the stack. Also create a stack frame object for the first variable
367     /// argument.
368     void writeVarArgRegs(std::vector<SDValue> &OutChains, const MipsCC &CC,
369                          SDValue Chain, DebugLoc DL, SelectionDAG &DAG) const;
370 
371     virtual SDValue
372       LowerFormalArguments(SDValue Chain,
373                            CallingConv::ID CallConv, bool isVarArg,
374                            const SmallVectorImpl<ISD::InputArg> &Ins,
375                            DebugLoc dl, SelectionDAG &DAG,
376                            SmallVectorImpl<SDValue> &InVals) const;
377 
378     SDValue passArgOnStack(SDValue StackPtr, unsigned Offset, SDValue Chain,
379                            SDValue Arg, DebugLoc DL, bool IsTailCall,
380                            SelectionDAG &DAG) const;
381 
382     virtual SDValue
383       LowerCall(TargetLowering::CallLoweringInfo &CLI,
384                 SmallVectorImpl<SDValue> &InVals) const;
385 
386     virtual bool
387       CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
388                      bool isVarArg,
389                      const SmallVectorImpl<ISD::OutputArg> &Outs,
390                      LLVMContext &Context) const;
391 
392     virtual SDValue
393       LowerReturn(SDValue Chain,
394                   CallingConv::ID CallConv, bool isVarArg,
395                   const SmallVectorImpl<ISD::OutputArg> &Outs,
396                   const SmallVectorImpl<SDValue> &OutVals,
397                   DebugLoc dl, SelectionDAG &DAG) const;
398 
399     // Inline asm support
400     ConstraintType getConstraintType(const std::string &Constraint) const;
401 
402     /// Examine constraint string and operand type and determine a weight value.
403     /// The operand object must already have been set up with the operand type.
404     ConstraintWeight getSingleConstraintMatchWeight(
405       AsmOperandInfo &info, const char *constraint) const;
406 
407     std::pair<unsigned, const TargetRegisterClass*>
408               getRegForInlineAsmConstraint(const std::string &Constraint,
409               EVT VT) const;
410 
411     /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
412     /// vector.  If it is invalid, don't add anything to Ops. If hasMemory is
413     /// true it means one of the asm constraint of the inline asm instruction
414     /// being processed is 'm'.
415     virtual void LowerAsmOperandForConstraint(SDValue Op,
416                                               std::string &Constraint,
417                                               std::vector<SDValue> &Ops,
418                                               SelectionDAG &DAG) const;
419 
420     virtual bool isLegalAddressingMode(const AddrMode &AM, Type *Ty) const;
421 
422     virtual bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const;
423 
424     virtual EVT getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
425                                     unsigned SrcAlign,
426                                     bool IsMemset, bool ZeroMemset,
427                                     bool MemcpyStrSrc,
428                                     MachineFunction &MF) const;
429 
430     /// isFPImmLegal - Returns true if the target can instruction select the
431     /// specified FP immediate natively. If false, the legalizer will
432     /// materialize the FP immediate as a load from a constant pool.
433     virtual bool isFPImmLegal(const APFloat &Imm, EVT VT) const;
434 
435     virtual unsigned getJumpTableEncoding() const;
436 
437     MachineBasicBlock *emitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
438                     unsigned Size, unsigned BinOpcode, bool Nand = false) const;
439     MachineBasicBlock *emitAtomicBinaryPartword(MachineInstr *MI,
440                     MachineBasicBlock *BB, unsigned Size, unsigned BinOpcode,
441                     bool Nand = false) const;
442     MachineBasicBlock *emitAtomicCmpSwap(MachineInstr *MI,
443                                   MachineBasicBlock *BB, unsigned Size) const;
444     MachineBasicBlock *emitAtomicCmpSwapPartword(MachineInstr *MI,
445                                   MachineBasicBlock *BB, unsigned Size) const;
446   };
447 
448   /// Create MipsTargetLowering objects.
449   const MipsTargetLowering *createMips16TargetLowering(MipsTargetMachine &TM);
450   const MipsTargetLowering *createMipsSETargetLowering(MipsTargetMachine &TM);
451 }
452 
453 #endif // MipsISELLOWERING_H
454