1 //===-- X86AsmPrinter.cpp - Convert X86 LLVM code to AT&T assembly --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains a printer that converts from our internal representation
11 // of machine-dependent LLVM code to AT&T format assembly
12 // language. This printer is the output mechanism used by `llc'.
14 //===----------------------------------------------------------------------===//
16 #define DEBUG_TYPE "asm-printer"
17 #include "X86AsmPrinter.h"
18 #include "X86ATTInstPrinter.h"
19 #include "X86IntelInstPrinter.h"
20 #include "X86MCInstLower.h"
23 #include "X86COFFMachineModuleInfo.h"
24 #include "X86MachineFunctionInfo.h"
25 #include "X86TargetMachine.h"
26 #include "llvm/CallingConv.h"
27 #include "llvm/DerivedTypes.h"
28 #include "llvm/Module.h"
29 #include "llvm/Type.h"
30 #include "llvm/Assembly/Writer.h"
31 #include "llvm/MC/MCContext.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/Support/ErrorHandling.h"
38 #include "llvm/Support/FormattedStream.h"
39 #include "llvm/MC/MCAsmInfo.h"
40 #include "llvm/Target/TargetLoweringObjectFile.h"
41 #include "llvm/Target/TargetOptions.h"
42 #include "llvm/Target/TargetRegistry.h"
43 #include "llvm/ADT/SmallString.h"
44 #include "llvm/ADT/Statistic.h"
47 STATISTIC(EmittedInsts, "Number of machine instrs printed");
49 //===----------------------------------------------------------------------===//
50 // Primitive Helper Functions.
51 //===----------------------------------------------------------------------===//
53 void X86AsmPrinter::printMCInst(const MCInst *MI) {
54 if (MAI->getAssemblerDialect() == 0)
55 X86ATTInstPrinter(O, *MAI).printInstruction(MI);
57 X86IntelInstPrinter(O, *MAI).printInstruction(MI);
60 void X86AsmPrinter::PrintPICBaseSymbol() const {
61 const TargetLowering *TLI = TM.getTargetLowering();
62 O << *static_cast<const X86TargetLowering*>(TLI)->getPICBaseSymbol(MF,
66 void X86AsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
67 unsigned FnAlign = MF.getAlignment();
68 const Function *F = MF.getFunction();
70 if (Subtarget->isTargetCygMing()) {
71 X86COFFMachineModuleInfo &COFFMMI =
72 MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
73 COFFMMI.DecorateCygMingName(CurrentFnSym, OutContext, F,
77 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
78 EmitAlignment(FnAlign, F);
80 switch (F->getLinkage()) {
81 default: llvm_unreachable("Unknown linkage type!");
82 case Function::InternalLinkage: // Symbols default to internal.
83 case Function::PrivateLinkage:
85 case Function::DLLExportLinkage:
86 case Function::ExternalLinkage:
87 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_Global);
89 case Function::LinkerPrivateLinkage:
90 case Function::LinkOnceAnyLinkage:
91 case Function::LinkOnceODRLinkage:
92 case Function::WeakAnyLinkage:
93 case Function::WeakODRLinkage:
94 if (Subtarget->isTargetDarwin()) {
95 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_Global);
96 O << MAI->getWeakDefDirective() << *CurrentFnSym << '\n';
97 } else if (Subtarget->isTargetCygMing()) {
98 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_Global);
99 // FIXME: linkonce should be a section attribute, handled by COFF Section
101 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
102 O << "\t.linkonce discard\n";
104 O << "\t.weak\t" << *CurrentFnSym << '\n';
109 printVisibility(CurrentFnSym, F->getVisibility());
111 if (MAI->hasDotTypeDotSizeDirective()) {
112 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
113 } else if (Subtarget->isTargetCygMing()) {
114 O << "\t.def\t " << *CurrentFnSym;
116 (F->hasInternalLinkage() ? COFF::C_STAT : COFF::C_EXT)
117 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
121 O << *CurrentFnSym << ':';
123 O.PadToColumn(MAI->getCommentColumn());
124 O << MAI->getCommentString() << ' ';
125 WriteAsOperand(O, F, /*PrintType=*/false, F->getParent());
129 // Add some workaround for linkonce linkage on Cygwin\MinGW
130 if (Subtarget->isTargetCygMing() &&
131 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
132 O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
135 /// runOnMachineFunction - This uses the printMachineInstruction()
136 /// method to print assembly for each instruction.
138 bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
139 const Function *F = MF.getFunction();
140 CallingConv::ID CC = F->getCallingConv();
142 SetupMachineFunction(MF);
145 if (Subtarget->isTargetCOFF()) {
146 X86COFFMachineModuleInfo &COFFMMI =
147 MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
149 // Populate function information map. Don't want to populate
150 // non-stdcall or non-fastcall functions' information right now.
151 if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
152 COFFMMI.AddFunctionInfo(F, *MF.getInfo<X86MachineFunctionInfo>());
155 // Print out constants referenced by the function
156 EmitConstantPool(MF.getConstantPool());
158 // Print the 'header' of function
159 emitFunctionHeader(MF);
161 // Emit pre-function debug and/or EH information.
162 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
163 DW->BeginFunction(&MF);
165 // Print out code for the function.
166 bool hasAnyRealCode = false;
167 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
169 // Print a label for the basic block.
170 EmitBasicBlockStart(I);
171 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
173 // Print the assembly for the instruction.
175 hasAnyRealCode = true;
176 printMachineInstruction(II);
180 if (Subtarget->isTargetDarwin() && !hasAnyRealCode) {
181 // If the function is empty, then we need to emit *something*. Otherwise,
182 // the function's label might be associated with something that it wasn't
183 // meant to be associated with. We emit a noop in this situation.
184 // We are assuming inline asms are code.
188 if (MAI->hasDotTypeDotSizeDirective())
189 O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
191 // Emit post-function debug information.
192 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
193 DW->EndFunction(&MF);
195 // Print out jump tables referenced by the function.
196 EmitJumpTableInfo(MF);
198 // We didn't modify anything.
202 /// printSymbolOperand - Print a raw symbol reference operand. This handles
203 /// jump tables, constant pools, global address and external symbols, all of
204 /// which print to a label with various suffixes for relocation types etc.
205 void X86AsmPrinter::printSymbolOperand(const MachineOperand &MO) {
206 switch (MO.getType()) {
207 default: llvm_unreachable("unknown symbol type!");
208 case MachineOperand::MO_JumpTableIndex:
209 O << *GetJTISymbol(MO.getIndex());
211 case MachineOperand::MO_ConstantPoolIndex:
212 O << *GetCPISymbol(MO.getIndex());
213 printOffset(MO.getOffset());
215 case MachineOperand::MO_GlobalAddress: {
216 const GlobalValue *GV = MO.getGlobal();
219 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
220 GVSym = GetSymbolWithGlobalValueBase(GV, "$stub");
221 else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
222 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
223 MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
224 GVSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
226 GVSym = GetGlobalValueSymbol(GV);
228 if (Subtarget->isTargetCygMing()) {
229 X86COFFMachineModuleInfo &COFFMMI =
230 MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
231 COFFMMI.DecorateCygMingName(GVSym, OutContext, GV, *TM.getTargetData());
234 // Handle dllimport linkage.
235 if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
236 GVSym = OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName());
238 if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
239 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) {
240 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
242 const MCSymbol *&StubSym =
243 MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym);
245 StubSym = GetGlobalValueSymbol(GV);
247 } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){
248 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
249 const MCSymbol *&StubSym =
250 MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry(Sym);
252 StubSym = GetGlobalValueSymbol(GV);
253 } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
254 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
255 const MCSymbol *&StubSym =
256 MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
258 StubSym = GetGlobalValueSymbol(GV);
261 // If the name begins with a dollar-sign, enclose it in parens. We do this
262 // to avoid having it look like an integer immediate to the assembler.
263 if (GVSym->getName()[0] != '$')
266 O << '(' << *GVSym << ')';
267 printOffset(MO.getOffset());
270 case MachineOperand::MO_ExternalSymbol: {
271 const MCSymbol *SymToPrint;
272 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
273 SmallString<128> TempNameStr;
274 TempNameStr += StringRef(MO.getSymbolName());
275 TempNameStr += StringRef("$stub");
277 const MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
278 const MCSymbol *&StubSym =
279 MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
281 TempNameStr.erase(TempNameStr.end()-5, TempNameStr.end());
282 StubSym = OutContext.GetOrCreateSymbol(TempNameStr.str());
284 SymToPrint = StubSym;
286 SymToPrint = GetExternalSymbolSymbol(MO.getSymbolName());
289 // If the name begins with a dollar-sign, enclose it in parens. We do this
290 // to avoid having it look like an integer immediate to the assembler.
291 if (SymToPrint->getName()[0] != '$')
294 O << '(' << *SymToPrint << '(';
299 switch (MO.getTargetFlags()) {
301 llvm_unreachable("Unknown target flag on GV operand");
302 case X86II::MO_NO_FLAG: // No flag.
304 case X86II::MO_DARWIN_NONLAZY:
305 case X86II::MO_DLLIMPORT:
306 case X86II::MO_DARWIN_STUB:
307 // These affect the name of the symbol, not any suffix.
309 case X86II::MO_GOT_ABSOLUTE_ADDRESS:
311 PrintPICBaseSymbol();
314 case X86II::MO_PIC_BASE_OFFSET:
315 case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
316 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
318 PrintPICBaseSymbol();
320 case X86II::MO_TLSGD: O << "@TLSGD"; break;
321 case X86II::MO_GOTTPOFF: O << "@GOTTPOFF"; break;
322 case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
323 case X86II::MO_TPOFF: O << "@TPOFF"; break;
324 case X86II::MO_NTPOFF: O << "@NTPOFF"; break;
325 case X86II::MO_GOTPCREL: O << "@GOTPCREL"; break;
326 case X86II::MO_GOT: O << "@GOT"; break;
327 case X86II::MO_GOTOFF: O << "@GOTOFF"; break;
328 case X86II::MO_PLT: O << "@PLT"; break;
332 /// print_pcrel_imm - This is used to print an immediate value that ends up
333 /// being encoded as a pc-relative value. These print slightly differently, for
334 /// example, a $ is not emitted.
335 void X86AsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo) {
336 const MachineOperand &MO = MI->getOperand(OpNo);
337 switch (MO.getType()) {
338 default: llvm_unreachable("Unknown pcrel immediate operand");
339 case MachineOperand::MO_Immediate:
342 case MachineOperand::MO_MachineBasicBlock:
343 O << *MO.getMBB()->getSymbol(OutContext);
345 case MachineOperand::MO_GlobalAddress:
346 case MachineOperand::MO_ExternalSymbol:
347 printSymbolOperand(MO);
353 void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
354 const char *Modifier) {
355 const MachineOperand &MO = MI->getOperand(OpNo);
356 switch (MO.getType()) {
357 default: llvm_unreachable("unknown operand type!");
358 case MachineOperand::MO_Register: {
360 unsigned Reg = MO.getReg();
361 if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
362 EVT VT = (strcmp(Modifier+6,"64") == 0) ?
363 MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
364 ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
365 Reg = getX86SubSuperRegister(Reg, VT);
367 O << X86ATTInstPrinter::getRegisterName(Reg);
371 case MachineOperand::MO_Immediate:
372 O << '$' << MO.getImm();
375 case MachineOperand::MO_JumpTableIndex:
376 case MachineOperand::MO_ConstantPoolIndex:
377 case MachineOperand::MO_GlobalAddress:
378 case MachineOperand::MO_ExternalSymbol: {
380 printSymbolOperand(MO);
386 void X86AsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
387 unsigned char value = MI->getOperand(Op).getImm();
388 assert(value <= 7 && "Invalid ssecc argument!");
390 case 0: O << "eq"; break;
391 case 1: O << "lt"; break;
392 case 2: O << "le"; break;
393 case 3: O << "unord"; break;
394 case 4: O << "neq"; break;
395 case 5: O << "nlt"; break;
396 case 6: O << "nle"; break;
397 case 7: O << "ord"; break;
401 void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
402 const char *Modifier) {
403 const MachineOperand &BaseReg = MI->getOperand(Op);
404 const MachineOperand &IndexReg = MI->getOperand(Op+2);
405 const MachineOperand &DispSpec = MI->getOperand(Op+3);
407 // If we really don't want to print out (rip), don't.
408 bool HasBaseReg = BaseReg.getReg() != 0;
409 if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
410 BaseReg.getReg() == X86::RIP)
413 // HasParenPart - True if we will print out the () part of the mem ref.
414 bool HasParenPart = IndexReg.getReg() || HasBaseReg;
416 if (DispSpec.isImm()) {
417 int DispVal = DispSpec.getImm();
418 if (DispVal || !HasParenPart)
421 assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
422 DispSpec.isJTI() || DispSpec.isSymbol());
423 printSymbolOperand(MI->getOperand(Op+3));
427 assert(IndexReg.getReg() != X86::ESP &&
428 "X86 doesn't allow scaling by ESP");
432 printOperand(MI, Op, Modifier);
434 if (IndexReg.getReg()) {
436 printOperand(MI, Op+2, Modifier);
437 unsigned ScaleVal = MI->getOperand(Op+1).getImm();
439 O << ',' << ScaleVal;
445 void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
446 const char *Modifier) {
447 assert(isMem(MI, Op) && "Invalid memory reference!");
448 const MachineOperand &Segment = MI->getOperand(Op+4);
449 if (Segment.getReg()) {
450 printOperand(MI, Op+4, Modifier);
453 printLeaMemReference(MI, Op, Modifier);
456 void X86AsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
457 PrintPICBaseSymbol();
459 PrintPICBaseSymbol();
463 bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode) {
464 unsigned Reg = MO.getReg();
466 default: return true; // Unknown mode.
467 case 'b': // Print QImode register
468 Reg = getX86SubSuperRegister(Reg, MVT::i8);
470 case 'h': // Print QImode high register
471 Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
473 case 'w': // Print HImode register
474 Reg = getX86SubSuperRegister(Reg, MVT::i16);
476 case 'k': // Print SImode register
477 Reg = getX86SubSuperRegister(Reg, MVT::i32);
479 case 'q': // Print DImode register
480 Reg = getX86SubSuperRegister(Reg, MVT::i64);
484 O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
488 /// PrintAsmOperand - Print out an operand for an inline asm expression.
490 bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
492 const char *ExtraCode) {
493 // Does this asm operand have a single letter operand modifier?
494 if (ExtraCode && ExtraCode[0]) {
495 if (ExtraCode[1] != 0) return true; // Unknown modifier.
497 const MachineOperand &MO = MI->getOperand(OpNo);
499 switch (ExtraCode[0]) {
500 default: return true; // Unknown modifier.
501 case 'a': // This is an address. Currently only 'i' and 'r' are expected.
506 if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
507 printSymbolOperand(MO);
512 printOperand(MI, OpNo);
518 case 'c': // Don't print "$" before a global var name or constant.
521 else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
522 printSymbolOperand(MO);
524 printOperand(MI, OpNo);
527 case 'A': // Print '*' before a register (it must be a register)
530 printOperand(MI, OpNo);
535 case 'b': // Print QImode register
536 case 'h': // Print QImode high register
537 case 'w': // Print HImode register
538 case 'k': // Print SImode register
539 case 'q': // Print DImode register
541 return printAsmMRegister(MO, ExtraCode[0]);
542 printOperand(MI, OpNo);
545 case 'P': // This is the operand of a call, treat specially.
546 print_pcrel_imm(MI, OpNo);
549 case 'n': // Negate the immediate or print a '-' before the operand.
550 // Note: this is a temporary solution. It should be handled target
551 // independently as part of the 'MC' work.
560 printOperand(MI, OpNo);
564 bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
565 unsigned OpNo, unsigned AsmVariant,
566 const char *ExtraCode) {
567 if (ExtraCode && ExtraCode[0]) {
568 if (ExtraCode[1] != 0) return true; // Unknown modifier.
570 switch (ExtraCode[0]) {
571 default: return true; // Unknown modifier.
572 case 'b': // Print QImode register
573 case 'h': // Print QImode high register
574 case 'w': // Print HImode register
575 case 'k': // Print SImode register
576 case 'q': // Print SImode register
577 // These only apply to registers, ignore on mem.
579 case 'P': // Don't print @PLT, but do print as memory.
580 printMemReference(MI, OpNo, "no-rip");
584 printMemReference(MI, OpNo);
590 /// printMachineInstruction -- Print out a single X86 LLVM instruction MI in
591 /// AT&T syntax to the current output stream.
593 void X86AsmPrinter::printMachineInstruction(const MachineInstr *MI) {
596 processDebugLoc(MI, true);
598 printInstructionThroughMCStreamer(MI);
604 processDebugLoc(MI, false);
607 void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
608 if (Subtarget->isTargetDarwin()) {
609 // All darwin targets use mach-o.
610 TargetLoweringObjectFileMachO &TLOFMacho =
611 static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
613 MachineModuleInfoMachO &MMIMacho =
614 MMI->getObjFileInfo<MachineModuleInfoMachO>();
616 // Output stubs for dynamically-linked functions.
617 MachineModuleInfoMachO::SymbolListTy Stubs;
619 Stubs = MMIMacho.GetFnStubList();
620 if (!Stubs.empty()) {
621 const MCSection *TheSection =
622 TLOFMacho.getMachOSection("__IMPORT", "__jump_table",
623 MCSectionMachO::S_SYMBOL_STUBS |
624 MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
625 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
626 5, SectionKind::getMetadata());
627 OutStreamer.SwitchSection(TheSection);
629 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
630 O << *Stubs[i].first << ":\n";
631 // Get the MCSymbol without the $stub suffix.
632 O << "\t.indirect_symbol " << *Stubs[i].second;
633 O << "\n\thlt ; hlt ; hlt ; hlt ; hlt\n";
640 // Output stubs for external and common global variables.
641 Stubs = MMIMacho.GetGVStubList();
642 if (!Stubs.empty()) {
643 const MCSection *TheSection =
644 TLOFMacho.getMachOSection("__IMPORT", "__pointers",
645 MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
646 SectionKind::getMetadata());
647 OutStreamer.SwitchSection(TheSection);
649 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
650 O << *Stubs[i].first << ":\n\t.indirect_symbol " << *Stubs[i].second;
651 O << "\n\t.long\t0\n";
656 Stubs = MMIMacho.GetHiddenGVStubList();
657 if (!Stubs.empty()) {
658 OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
661 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
662 O << *Stubs[i].first << ":\n" << MAI->getData32bitsDirective();
663 O << *Stubs[i].second << '\n';
668 // Funny Darwin hack: This flag tells the linker that no global symbols
669 // contain code that falls through to other global symbols (e.g. the obvious
670 // implementation of multiple entry points). If this doesn't occur, the
671 // linker can safely perform dead code stripping. Since LLVM never
672 // generates code that does this, it is always safe to set.
673 OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
676 if (Subtarget->isTargetCOFF()) {
677 X86COFFMachineModuleInfo &COFFMMI =
678 MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
680 // Emit type information for external functions
681 for (X86COFFMachineModuleInfo::stub_iterator I = COFFMMI.stub_begin(),
682 E = COFFMMI.stub_end(); I != E; ++I) {
683 O << "\t.def\t " << I->getKeyData()
684 << ";\t.scl\t" << COFF::C_EXT
685 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
689 if (Subtarget->isTargetCygMing()) {
690 // Necessary for dllexport support
691 std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
693 TargetLoweringObjectFileCOFF &TLOFCOFF =
694 static_cast<TargetLoweringObjectFileCOFF&>(getObjFileLowering());
696 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
697 if (I->hasDLLExportLinkage()) {
698 MCSymbol *Sym = GetGlobalValueSymbol(I);
699 COFFMMI.DecorateCygMingName(Sym, OutContext, I, *TM.getTargetData());
700 DLLExportedFns.push_back(Sym);
703 for (Module::const_global_iterator I = M.global_begin(),
704 E = M.global_end(); I != E; ++I)
705 if (I->hasDLLExportLinkage())
706 DLLExportedGlobals.push_back(GetGlobalValueSymbol(I));
708 // Output linker support code for dllexported globals on windows.
709 if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
710 OutStreamer.SwitchSection(TLOFCOFF.getCOFFSection(".section .drectve",
712 SectionKind::getMetadata()));
713 for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i)
714 O << "\t.ascii \" -export:" << *DLLExportedGlobals[i] << ",data\"\n";
716 for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i)
717 O << "\t.ascii \" -export:" << *DLLExportedFns[i] << "\"\n";
724 //===----------------------------------------------------------------------===//
725 // Target Registry Stuff
726 //===----------------------------------------------------------------------===//
728 static MCInstPrinter *createX86MCInstPrinter(const Target &T,
729 unsigned SyntaxVariant,
730 const MCAsmInfo &MAI,
732 if (SyntaxVariant == 0)
733 return new X86ATTInstPrinter(O, MAI);
734 if (SyntaxVariant == 1)
735 return new X86IntelInstPrinter(O, MAI);
739 // Force static initialization.
740 extern "C" void LLVMInitializeX86AsmPrinter() {
741 RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
742 RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
744 TargetRegistry::RegisterMCInstPrinter(TheX86_32Target,createX86MCInstPrinter);
745 TargetRegistry::RegisterMCInstPrinter(TheX86_64Target,createX86MCInstPrinter);