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1 //===-- X86AsmPrinter.cpp - Convert X86 LLVM code to AT&T assembly --------===//
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 contains a printer that converts from our internal representation
11 // of machine-dependent LLVM code to X86 machine code.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "X86AsmPrinter.h"
16 #include "InstPrinter/X86ATTInstPrinter.h"
17 #include "InstPrinter/X86IntelInstPrinter.h"
18 #include "X86MCInstLower.h"
19 #include "X86.h"
20 #include "X86COFFMachineModuleInfo.h"
21 #include "X86MachineFunctionInfo.h"
22 #include "X86TargetMachine.h"
23 #include "llvm/CallingConv.h"
24 #include "llvm/DerivedTypes.h"
25 #include "llvm/Module.h"
26 #include "llvm/Type.h"
27 #include "llvm/Analysis/DebugInfo.h"
28 #include "llvm/Assembly/Writer.h"
29 #include "llvm/MC/MCAsmInfo.h"
30 #include "llvm/MC/MCContext.h"
31 #include "llvm/MC/MCExpr.h"
32 #include "llvm/MC/MCSectionMachO.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSymbol.h"
35 #include "llvm/CodeGen/MachineJumpTableInfo.h"
36 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
37 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
38 #include "llvm/Target/Mangler.h"
39 #include "llvm/Target/TargetOptions.h"
40 #include "llvm/Support/COFF.h"
41 #include "llvm/Support/Debug.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include "llvm/Support/TargetRegistry.h"
44 #include "llvm/ADT/SmallString.h"
45 using namespace llvm;
46 
47 //===----------------------------------------------------------------------===//
48 // Primitive Helper Functions.
49 //===----------------------------------------------------------------------===//
50 
51 /// runOnMachineFunction - Emit the function body.
52 ///
runOnMachineFunction(MachineFunction & MF)53 bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
54   SetupMachineFunction(MF);
55 
56   if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
57     bool Intrn = MF.getFunction()->hasInternalLinkage();
58     OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
59     OutStreamer.EmitCOFFSymbolStorageClass(Intrn ? COFF::IMAGE_SYM_CLASS_STATIC
60                                               : COFF::IMAGE_SYM_CLASS_EXTERNAL);
61     OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
62                                                << COFF::SCT_COMPLEX_TYPE_SHIFT);
63     OutStreamer.EndCOFFSymbolDef();
64   }
65 
66   // Have common code print out the function header with linkage info etc.
67   EmitFunctionHeader();
68 
69   // Emit the rest of the function body.
70   EmitFunctionBody();
71 
72   // We didn't modify anything.
73   return false;
74 }
75 
76 /// printSymbolOperand - Print a raw symbol reference operand.  This handles
77 /// jump tables, constant pools, global address and external symbols, all of
78 /// which print to a label with various suffixes for relocation types etc.
printSymbolOperand(const MachineOperand & MO,raw_ostream & O)79 void X86AsmPrinter::printSymbolOperand(const MachineOperand &MO,
80                                        raw_ostream &O) {
81   switch (MO.getType()) {
82   default: llvm_unreachable("unknown symbol type!");
83   case MachineOperand::MO_JumpTableIndex:
84     O << *GetJTISymbol(MO.getIndex());
85     break;
86   case MachineOperand::MO_ConstantPoolIndex:
87     O << *GetCPISymbol(MO.getIndex());
88     printOffset(MO.getOffset(), O);
89     break;
90   case MachineOperand::MO_GlobalAddress: {
91     const GlobalValue *GV = MO.getGlobal();
92 
93     MCSymbol *GVSym;
94     if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
95       GVSym = GetSymbolWithGlobalValueBase(GV, "$stub");
96     else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
97              MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
98              MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
99       GVSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
100     else
101       GVSym = Mang->getSymbol(GV);
102 
103     // Handle dllimport linkage.
104     if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
105       GVSym = OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName());
106 
107     if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
108         MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) {
109       MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
110       MachineModuleInfoImpl::StubValueTy &StubSym =
111         MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym);
112       if (StubSym.getPointer() == 0)
113         StubSym = MachineModuleInfoImpl::
114           StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
115     } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){
116       MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
117       MachineModuleInfoImpl::StubValueTy &StubSym =
118         MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry(Sym);
119       if (StubSym.getPointer() == 0)
120         StubSym = MachineModuleInfoImpl::
121           StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
122     } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
123       MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
124       MachineModuleInfoImpl::StubValueTy &StubSym =
125         MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
126       if (StubSym.getPointer() == 0)
127         StubSym = MachineModuleInfoImpl::
128           StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
129     }
130 
131     // If the name begins with a dollar-sign, enclose it in parens.  We do this
132     // to avoid having it look like an integer immediate to the assembler.
133     if (GVSym->getName()[0] != '$')
134       O << *GVSym;
135     else
136       O << '(' << *GVSym << ')';
137     printOffset(MO.getOffset(), O);
138     break;
139   }
140   case MachineOperand::MO_ExternalSymbol: {
141     const MCSymbol *SymToPrint;
142     if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
143       SmallString<128> TempNameStr;
144       TempNameStr += StringRef(MO.getSymbolName());
145       TempNameStr += StringRef("$stub");
146 
147       MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
148       MachineModuleInfoImpl::StubValueTy &StubSym =
149         MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
150       if (StubSym.getPointer() == 0) {
151         TempNameStr.erase(TempNameStr.end()-5, TempNameStr.end());
152         StubSym = MachineModuleInfoImpl::
153           StubValueTy(OutContext.GetOrCreateSymbol(TempNameStr.str()),
154                       true);
155       }
156       SymToPrint = StubSym.getPointer();
157     } else {
158       SymToPrint = GetExternalSymbolSymbol(MO.getSymbolName());
159     }
160 
161     // If the name begins with a dollar-sign, enclose it in parens.  We do this
162     // to avoid having it look like an integer immediate to the assembler.
163     if (SymToPrint->getName()[0] != '$')
164       O << *SymToPrint;
165     else
166       O << '(' << *SymToPrint << '(';
167     break;
168   }
169   }
170 
171   switch (MO.getTargetFlags()) {
172   default:
173     llvm_unreachable("Unknown target flag on GV operand");
174   case X86II::MO_NO_FLAG:    // No flag.
175     break;
176   case X86II::MO_DARWIN_NONLAZY:
177   case X86II::MO_DLLIMPORT:
178   case X86II::MO_DARWIN_STUB:
179     // These affect the name of the symbol, not any suffix.
180     break;
181   case X86II::MO_GOT_ABSOLUTE_ADDRESS:
182     O << " + [.-" << *MF->getPICBaseSymbol() << ']';
183     break;
184   case X86II::MO_PIC_BASE_OFFSET:
185   case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
186   case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
187     O << '-' << *MF->getPICBaseSymbol();
188     break;
189   case X86II::MO_TLSGD:     O << "@TLSGD";     break;
190   case X86II::MO_GOTTPOFF:  O << "@GOTTPOFF";  break;
191   case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
192   case X86II::MO_TPOFF:     O << "@TPOFF";     break;
193   case X86II::MO_NTPOFF:    O << "@NTPOFF";    break;
194   case X86II::MO_GOTPCREL:  O << "@GOTPCREL";  break;
195   case X86II::MO_GOT:       O << "@GOT";       break;
196   case X86II::MO_GOTOFF:    O << "@GOTOFF";    break;
197   case X86II::MO_PLT:       O << "@PLT";       break;
198   case X86II::MO_TLVP:      O << "@TLVP";      break;
199   case X86II::MO_TLVP_PIC_BASE:
200     O << "@TLVP" << '-' << *MF->getPICBaseSymbol();
201     break;
202   }
203 }
204 
205 /// print_pcrel_imm - This is used to print an immediate value that ends up
206 /// being encoded as a pc-relative value.  These print slightly differently, for
207 /// example, a $ is not emitted.
print_pcrel_imm(const MachineInstr * MI,unsigned OpNo,raw_ostream & O)208 void X86AsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo,
209                                     raw_ostream &O) {
210   const MachineOperand &MO = MI->getOperand(OpNo);
211   switch (MO.getType()) {
212   default: llvm_unreachable("Unknown pcrel immediate operand");
213   case MachineOperand::MO_Register:
214     // pc-relativeness was handled when computing the value in the reg.
215     printOperand(MI, OpNo, O);
216     return;
217   case MachineOperand::MO_Immediate:
218     O << MO.getImm();
219     return;
220   case MachineOperand::MO_MachineBasicBlock:
221     O << *MO.getMBB()->getSymbol();
222     return;
223   case MachineOperand::MO_GlobalAddress:
224   case MachineOperand::MO_ExternalSymbol:
225     printSymbolOperand(MO, O);
226     return;
227   }
228 }
229 
230 
printOperand(const MachineInstr * MI,unsigned OpNo,raw_ostream & O,const char * Modifier)231 void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
232                                  raw_ostream &O, const char *Modifier) {
233   const MachineOperand &MO = MI->getOperand(OpNo);
234   switch (MO.getType()) {
235   default: llvm_unreachable("unknown operand type!");
236   case MachineOperand::MO_Register: {
237     O << '%';
238     unsigned Reg = MO.getReg();
239     if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
240       EVT VT = (strcmp(Modifier+6,"64") == 0) ?
241         MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
242                     ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
243       Reg = getX86SubSuperRegister(Reg, VT);
244     }
245     O << X86ATTInstPrinter::getRegisterName(Reg);
246     return;
247   }
248 
249   case MachineOperand::MO_Immediate:
250     O << '$' << MO.getImm();
251     return;
252 
253   case MachineOperand::MO_JumpTableIndex:
254   case MachineOperand::MO_ConstantPoolIndex:
255   case MachineOperand::MO_GlobalAddress:
256   case MachineOperand::MO_ExternalSymbol: {
257     O << '$';
258     printSymbolOperand(MO, O);
259     break;
260   }
261   }
262 }
263 
printSSECC(const MachineInstr * MI,unsigned Op,raw_ostream & O)264 void X86AsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op,
265                                raw_ostream &O) {
266   unsigned char value = MI->getOperand(Op).getImm();
267   assert(value <= 7 && "Invalid ssecc argument!");
268   switch (value) {
269   case 0: O << "eq"; break;
270   case 1: O << "lt"; break;
271   case 2: O << "le"; break;
272   case 3: O << "unord"; break;
273   case 4: O << "neq"; break;
274   case 5: O << "nlt"; break;
275   case 6: O << "nle"; break;
276   case 7: O << "ord"; break;
277   }
278 }
279 
printLeaMemReference(const MachineInstr * MI,unsigned Op,raw_ostream & O,const char * Modifier)280 void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
281                                          raw_ostream &O, const char *Modifier) {
282   const MachineOperand &BaseReg  = MI->getOperand(Op);
283   const MachineOperand &IndexReg = MI->getOperand(Op+2);
284   const MachineOperand &DispSpec = MI->getOperand(Op+3);
285 
286   // If we really don't want to print out (rip), don't.
287   bool HasBaseReg = BaseReg.getReg() != 0;
288   if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
289       BaseReg.getReg() == X86::RIP)
290     HasBaseReg = false;
291 
292   // HasParenPart - True if we will print out the () part of the mem ref.
293   bool HasParenPart = IndexReg.getReg() || HasBaseReg;
294 
295   if (DispSpec.isImm()) {
296     int DispVal = DispSpec.getImm();
297     if (DispVal || !HasParenPart)
298       O << DispVal;
299   } else {
300     assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
301            DispSpec.isJTI() || DispSpec.isSymbol());
302     printSymbolOperand(MI->getOperand(Op+3), O);
303   }
304 
305   if (Modifier && strcmp(Modifier, "H") == 0)
306     O << "+8";
307 
308   if (HasParenPart) {
309     assert(IndexReg.getReg() != X86::ESP &&
310            "X86 doesn't allow scaling by ESP");
311 
312     O << '(';
313     if (HasBaseReg)
314       printOperand(MI, Op, O, Modifier);
315 
316     if (IndexReg.getReg()) {
317       O << ',';
318       printOperand(MI, Op+2, O, Modifier);
319       unsigned ScaleVal = MI->getOperand(Op+1).getImm();
320       if (ScaleVal != 1)
321         O << ',' << ScaleVal;
322     }
323     O << ')';
324   }
325 }
326 
printMemReference(const MachineInstr * MI,unsigned Op,raw_ostream & O,const char * Modifier)327 void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
328                                       raw_ostream &O, const char *Modifier) {
329   assert(isMem(MI, Op) && "Invalid memory reference!");
330   const MachineOperand &Segment = MI->getOperand(Op+4);
331   if (Segment.getReg()) {
332     printOperand(MI, Op+4, O, Modifier);
333     O << ':';
334   }
335   printLeaMemReference(MI, Op, O, Modifier);
336 }
337 
printPICLabel(const MachineInstr * MI,unsigned Op,raw_ostream & O)338 void X86AsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op,
339                                   raw_ostream &O) {
340   O << *MF->getPICBaseSymbol() << '\n';
341   O << *MF->getPICBaseSymbol() << ':';
342 }
343 
printAsmMRegister(const MachineOperand & MO,char Mode,raw_ostream & O)344 bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
345                                       raw_ostream &O) {
346   unsigned Reg = MO.getReg();
347   switch (Mode) {
348   default: return true;  // Unknown mode.
349   case 'b': // Print QImode register
350     Reg = getX86SubSuperRegister(Reg, MVT::i8);
351     break;
352   case 'h': // Print QImode high register
353     Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
354     break;
355   case 'w': // Print HImode register
356     Reg = getX86SubSuperRegister(Reg, MVT::i16);
357     break;
358   case 'k': // Print SImode register
359     Reg = getX86SubSuperRegister(Reg, MVT::i32);
360     break;
361   case 'q': // Print DImode register
362     Reg = getX86SubSuperRegister(Reg, MVT::i64);
363     break;
364   }
365 
366   O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
367   return false;
368 }
369 
370 /// PrintAsmOperand - Print out an operand for an inline asm expression.
371 ///
PrintAsmOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)372 bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
373                                     unsigned AsmVariant,
374                                     const char *ExtraCode, raw_ostream &O) {
375   // Does this asm operand have a single letter operand modifier?
376   if (ExtraCode && ExtraCode[0]) {
377     if (ExtraCode[1] != 0) return true; // Unknown modifier.
378 
379     const MachineOperand &MO = MI->getOperand(OpNo);
380 
381     switch (ExtraCode[0]) {
382     default: return true;  // Unknown modifier.
383     case 'a': // This is an address.  Currently only 'i' and 'r' are expected.
384       if (MO.isImm()) {
385         O << MO.getImm();
386         return false;
387       }
388       if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
389         printSymbolOperand(MO, O);
390         if (Subtarget->isPICStyleRIPRel())
391           O << "(%rip)";
392         return false;
393       }
394       if (MO.isReg()) {
395         O << '(';
396         printOperand(MI, OpNo, O);
397         O << ')';
398         return false;
399       }
400       return true;
401 
402     case 'c': // Don't print "$" before a global var name or constant.
403       if (MO.isImm())
404         O << MO.getImm();
405       else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
406         printSymbolOperand(MO, O);
407       else
408         printOperand(MI, OpNo, O);
409       return false;
410 
411     case 'A': // Print '*' before a register (it must be a register)
412       if (MO.isReg()) {
413         O << '*';
414         printOperand(MI, OpNo, O);
415         return false;
416       }
417       return true;
418 
419     case 'b': // Print QImode register
420     case 'h': // Print QImode high register
421     case 'w': // Print HImode register
422     case 'k': // Print SImode register
423     case 'q': // Print DImode register
424       if (MO.isReg())
425         return printAsmMRegister(MO, ExtraCode[0], O);
426       printOperand(MI, OpNo, O);
427       return false;
428 
429     case 'P': // This is the operand of a call, treat specially.
430       print_pcrel_imm(MI, OpNo, O);
431       return false;
432 
433     case 'n':  // Negate the immediate or print a '-' before the operand.
434       // Note: this is a temporary solution. It should be handled target
435       // independently as part of the 'MC' work.
436       if (MO.isImm()) {
437         O << -MO.getImm();
438         return false;
439       }
440       O << '-';
441     }
442   }
443 
444   printOperand(MI, OpNo, O);
445   return false;
446 }
447 
PrintAsmMemoryOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)448 bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
449                                           unsigned OpNo, unsigned AsmVariant,
450                                           const char *ExtraCode,
451                                           raw_ostream &O) {
452   if (ExtraCode && ExtraCode[0]) {
453     if (ExtraCode[1] != 0) return true; // Unknown modifier.
454 
455     switch (ExtraCode[0]) {
456     default: return true;  // Unknown modifier.
457     case 'b': // Print QImode register
458     case 'h': // Print QImode high register
459     case 'w': // Print HImode register
460     case 'k': // Print SImode register
461     case 'q': // Print SImode register
462       // These only apply to registers, ignore on mem.
463       break;
464     case 'H':
465       printMemReference(MI, OpNo, O, "H");
466       return false;
467     case 'P': // Don't print @PLT, but do print as memory.
468       printMemReference(MI, OpNo, O, "no-rip");
469       return false;
470     }
471   }
472   printMemReference(MI, OpNo, O);
473   return false;
474 }
475 
EmitStartOfAsmFile(Module & M)476 void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
477   if (Subtarget->isTargetEnvMacho())
478     OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
479 }
480 
481 
EmitEndOfAsmFile(Module & M)482 void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
483   if (Subtarget->isTargetEnvMacho()) {
484     // All darwin targets use mach-o.
485     MachineModuleInfoMachO &MMIMacho =
486       MMI->getObjFileInfo<MachineModuleInfoMachO>();
487 
488     // Output stubs for dynamically-linked functions.
489     MachineModuleInfoMachO::SymbolListTy Stubs;
490 
491     Stubs = MMIMacho.GetFnStubList();
492     if (!Stubs.empty()) {
493       const MCSection *TheSection =
494         OutContext.getMachOSection("__IMPORT", "__jump_table",
495                                    MCSectionMachO::S_SYMBOL_STUBS |
496                                    MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
497                                    MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
498                                    5, SectionKind::getMetadata());
499       OutStreamer.SwitchSection(TheSection);
500 
501       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
502         // L_foo$stub:
503         OutStreamer.EmitLabel(Stubs[i].first);
504         //   .indirect_symbol _foo
505         OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
506                                         MCSA_IndirectSymbol);
507         // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
508         const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
509         OutStreamer.EmitBytes(StringRef(HltInsts, 5), 0/*addrspace*/);
510       }
511 
512       Stubs.clear();
513       OutStreamer.AddBlankLine();
514     }
515 
516     // Output stubs for external and common global variables.
517     Stubs = MMIMacho.GetGVStubList();
518     if (!Stubs.empty()) {
519       const MCSection *TheSection =
520         OutContext.getMachOSection("__IMPORT", "__pointers",
521                                    MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
522                                    SectionKind::getMetadata());
523       OutStreamer.SwitchSection(TheSection);
524 
525       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
526         // L_foo$non_lazy_ptr:
527         OutStreamer.EmitLabel(Stubs[i].first);
528         // .indirect_symbol _foo
529         MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
530         OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
531                                         MCSA_IndirectSymbol);
532         // .long 0
533         if (MCSym.getInt())
534           // External to current translation unit.
535           OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
536         else
537           // Internal to current translation unit.
538           //
539           // When we place the LSDA into the TEXT section, the type info
540           // pointers need to be indirect and pc-rel. We accomplish this by
541           // using NLPs.  However, sometimes the types are local to the file. So
542           // we need to fill in the value for the NLP in those cases.
543           OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
544                                                         OutContext),
545                                 4/*size*/, 0/*addrspace*/);
546       }
547       Stubs.clear();
548       OutStreamer.AddBlankLine();
549     }
550 
551     Stubs = MMIMacho.GetHiddenGVStubList();
552     if (!Stubs.empty()) {
553       OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
554       EmitAlignment(2);
555 
556       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
557         // L_foo$non_lazy_ptr:
558         OutStreamer.EmitLabel(Stubs[i].first);
559         // .long _foo
560         OutStreamer.EmitValue(MCSymbolRefExpr::
561                               Create(Stubs[i].second.getPointer(),
562                                      OutContext),
563                               4/*size*/, 0/*addrspace*/);
564       }
565       Stubs.clear();
566       OutStreamer.AddBlankLine();
567     }
568 
569     // Funny Darwin hack: This flag tells the linker that no global symbols
570     // contain code that falls through to other global symbols (e.g. the obvious
571     // implementation of multiple entry points).  If this doesn't occur, the
572     // linker can safely perform dead code stripping.  Since LLVM never
573     // generates code that does this, it is always safe to set.
574     OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
575   }
576 
577   if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
578       MMI->callsExternalVAFunctionWithFloatingPointArguments()) {
579     StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
580     MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
581     OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
582   }
583 
584   if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
585     X86COFFMachineModuleInfo &COFFMMI =
586       MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
587 
588     // Emit type information for external functions
589     typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
590     for (externals_iterator I = COFFMMI.externals_begin(),
591                             E = COFFMMI.externals_end();
592                             I != E; ++I) {
593       OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
594       OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
595       OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
596                                                << COFF::SCT_COMPLEX_TYPE_SHIFT);
597       OutStreamer.EndCOFFSymbolDef();
598     }
599 
600     // Necessary for dllexport support
601     std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
602 
603     const TargetLoweringObjectFileCOFF &TLOFCOFF =
604       static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());
605 
606     for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
607       if (I->hasDLLExportLinkage())
608         DLLExportedFns.push_back(Mang->getSymbol(I));
609 
610     for (Module::const_global_iterator I = M.global_begin(),
611            E = M.global_end(); I != E; ++I)
612       if (I->hasDLLExportLinkage())
613         DLLExportedGlobals.push_back(Mang->getSymbol(I));
614 
615     // Output linker support code for dllexported globals on windows.
616     if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
617       OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
618       SmallString<128> name;
619       for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
620         if (Subtarget->isTargetWindows())
621           name = " /EXPORT:";
622         else
623           name = " -export:";
624         name += DLLExportedGlobals[i]->getName();
625         if (Subtarget->isTargetWindows())
626           name += ",DATA";
627         else
628         name += ",data";
629         OutStreamer.EmitBytes(name, 0);
630       }
631 
632       for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
633         if (Subtarget->isTargetWindows())
634           name = " /EXPORT:";
635         else
636           name = " -export:";
637         name += DLLExportedFns[i]->getName();
638         OutStreamer.EmitBytes(name, 0);
639       }
640     }
641   }
642 
643   if (Subtarget->isTargetELF()) {
644     const TargetLoweringObjectFileELF &TLOFELF =
645       static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());
646 
647     MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
648 
649     // Output stubs for external and common global variables.
650     MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
651     if (!Stubs.empty()) {
652       OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
653       const TargetData *TD = TM.getTargetData();
654 
655       for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
656         OutStreamer.EmitLabel(Stubs[i].first);
657         OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
658                                     TD->getPointerSize(), 0);
659       }
660       Stubs.clear();
661     }
662   }
663 }
664 
665 MachineLocation
getDebugValueLocation(const MachineInstr * MI) const666 X86AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
667   MachineLocation Location;
668   assert (MI->getNumOperands() == 7 && "Invalid no. of machine operands!");
669   // Frame address.  Currently handles register +- offset only.
670 
671   if (MI->getOperand(0).isReg() && MI->getOperand(3).isImm())
672     Location.set(MI->getOperand(0).getReg(), MI->getOperand(3).getImm());
673   else {
674     DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
675   }
676   return Location;
677 }
678 
PrintDebugValueComment(const MachineInstr * MI,raw_ostream & O)679 void X86AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
680                                            raw_ostream &O) {
681   // Only the target-dependent form of DBG_VALUE should get here.
682   // Referencing the offset and metadata as NOps-2 and NOps-1 is
683   // probably portable to other targets; frame pointer location is not.
684   unsigned NOps = MI->getNumOperands();
685   assert(NOps==7);
686   O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
687   // cast away const; DIetc do not take const operands for some reason.
688   DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
689   if (V.getContext().isSubprogram())
690     O << DISubprogram(V.getContext()).getDisplayName() << ":";
691   O << V.getName();
692   O << " <- ";
693   // Frame address.  Currently handles register +- offset only.
694   O << '[';
695   if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg())
696     printOperand(MI, 0, O);
697   else
698     O << "undef";
699   O << '+'; printOperand(MI, 3, O);
700   O << ']';
701   O << "+";
702   printOperand(MI, NOps-2, O);
703 }
704 
705 
706 
707 //===----------------------------------------------------------------------===//
708 // Target Registry Stuff
709 //===----------------------------------------------------------------------===//
710 
711 // Force static initialization.
LLVMInitializeX86AsmPrinter()712 extern "C" void LLVMInitializeX86AsmPrinter() {
713   RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
714   RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
715 }
716