1 //===-- X86ATTAsmPrinter.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 "X86ATTAsmPrinter.h"
20 #include "X86MachineFunctionInfo.h"
21 #include "X86TargetMachine.h"
22 #include "X86TargetAsmInfo.h"
23 #include "llvm/CallingConv.h"
24 #include "llvm/DerivedTypes.h"
25 #include "llvm/Module.h"
26 #include "llvm/Type.h"
27 #include "llvm/ADT/Statistic.h"
28 #include "llvm/ADT/StringExtras.h"
29 #include "llvm/CodeGen/DwarfWriter.h"
30 #include "llvm/CodeGen/MachineJumpTableInfo.h"
31 #include "llvm/Support/Mangler.h"
32 #include "llvm/Support/raw_ostream.h"
33 #include "llvm/Target/TargetAsmInfo.h"
34 #include "llvm/Target/TargetOptions.h"
37 STATISTIC(EmittedInsts, "Number of machine instrs printed");
39 static std::string getPICLabelString(unsigned FnNum,
40 const TargetAsmInfo *TAI,
41 const X86Subtarget* Subtarget) {
43 if (Subtarget->isTargetDarwin())
44 label = "\"L" + utostr_32(FnNum) + "$pb\"";
45 else if (Subtarget->isTargetELF())
46 label = ".Lllvm$" + utostr_32(FnNum) + "." "$piclabel";
48 assert(0 && "Don't know how to print PIC label!\n");
53 static X86MachineFunctionInfo calculateFunctionInfo(const Function *F,
54 const TargetData *TD) {
55 X86MachineFunctionInfo Info;
58 switch (F->getCallingConv()) {
59 case CallingConv::X86_StdCall:
60 Info.setDecorationStyle(StdCall);
62 case CallingConv::X86_FastCall:
63 Info.setDecorationStyle(FastCall);
70 for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
71 AI != AE; ++AI, ++argNum) {
72 const Type* Ty = AI->getType();
74 // 'Dereference' type in case of byval parameter attribute
75 if (F->paramHasAttr(argNum, Attribute::ByVal))
76 Ty = cast<PointerType>(Ty)->getElementType();
78 // Size should be aligned to DWORD boundary
79 Size += ((TD->getTypePaddedSize(Ty) + 3)/4)*4;
82 // We're not supporting tooooo huge arguments :)
83 Info.setBytesToPopOnReturn((unsigned int)Size);
87 /// PrintUnmangledNameSafely - Print out the printable characters in the name.
88 /// Don't print things like \n or \0.
89 static void PrintUnmangledNameSafely(const Value *V, raw_ostream &OS) {
90 for (const char *Name = V->getNameStart(), *E = Name+V->getNameLen();
96 /// decorateName - Query FunctionInfoMap and use this information for various
98 void X86ATTAsmPrinter::decorateName(std::string &Name,
99 const GlobalValue *GV) {
100 const Function *F = dyn_cast<Function>(GV);
103 // We don't want to decorate non-stdcall or non-fastcall functions right now
104 unsigned CC = F->getCallingConv();
105 if (CC != CallingConv::X86_StdCall && CC != CallingConv::X86_FastCall)
108 // Decorate names only when we're targeting Cygwin/Mingw32 targets
109 if (!Subtarget->isTargetCygMing())
112 FMFInfoMap::const_iterator info_item = FunctionInfoMap.find(F);
114 const X86MachineFunctionInfo *Info;
115 if (info_item == FunctionInfoMap.end()) {
116 // Calculate apropriate function info and populate map
117 FunctionInfoMap[F] = calculateFunctionInfo(F, TM.getTargetData());
118 Info = &FunctionInfoMap[F];
120 Info = &info_item->second;
123 const FunctionType *FT = F->getFunctionType();
124 switch (Info->getDecorationStyle()) {
128 // "Pure" variadic functions do not receive @0 suffix.
129 if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
130 (FT->getNumParams() == 1 && F->hasStructRetAttr()))
131 Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
134 // "Pure" variadic functions do not receive @0 suffix.
135 if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
136 (FT->getNumParams() == 1 && F->hasStructRetAttr()))
137 Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
139 if (Name[0] == '_') {
146 assert(0 && "Unsupported DecorationStyle");
150 void X86ATTAsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
151 const Function *F = MF.getFunction();
153 decorateName(CurrentFnName, F);
155 SwitchToSection(TAI->SectionForGlobal(F));
157 unsigned FnAlign = 4;
158 if (F->hasFnAttr(Attribute::OptimizeForSize))
160 switch (F->getLinkage()) {
161 default: assert(0 && "Unknown linkage type!");
162 case Function::InternalLinkage: // Symbols default to internal.
163 case Function::PrivateLinkage:
164 EmitAlignment(FnAlign, F);
166 case Function::DLLExportLinkage:
167 case Function::ExternalLinkage:
168 EmitAlignment(FnAlign, F);
169 O << "\t.globl\t" << CurrentFnName << '\n';
171 case Function::LinkOnceLinkage:
172 case Function::WeakLinkage:
173 EmitAlignment(FnAlign, F);
174 if (Subtarget->isTargetDarwin()) {
175 O << "\t.globl\t" << CurrentFnName << '\n';
176 O << TAI->getWeakDefDirective() << CurrentFnName << '\n';
177 } else if (Subtarget->isTargetCygMing()) {
178 O << "\t.globl\t" << CurrentFnName << "\n"
179 "\t.linkonce discard\n";
181 O << "\t.weak\t" << CurrentFnName << '\n';
186 printVisibility(CurrentFnName, F->getVisibility());
188 if (Subtarget->isTargetELF())
189 O << "\t.type\t" << CurrentFnName << ",@function\n";
190 else if (Subtarget->isTargetCygMing()) {
191 O << "\t.def\t " << CurrentFnName
193 (F->hasInternalLinkage() ? COFF::C_STAT : COFF::C_EXT)
194 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
198 O << CurrentFnName << ":\n";
199 // Add some workaround for linkonce linkage on Cygwin\MinGW
200 if (Subtarget->isTargetCygMing() &&
201 (F->getLinkage() == Function::LinkOnceLinkage ||
202 F->getLinkage() == Function::WeakLinkage))
203 O << "Lllvm$workaround$fake$stub$" << CurrentFnName << ":\n";
206 /// runOnMachineFunction - This uses the printMachineInstruction()
207 /// method to print assembly for each instruction.
209 bool X86ATTAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
210 const Function *F = MF.getFunction();
212 unsigned CC = F->getCallingConv();
214 SetupMachineFunction(MF);
217 // Populate function information map. Actually, We don't want to populate
218 // non-stdcall or non-fastcall functions' information right now.
219 if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
220 FunctionInfoMap[F] = *MF.getInfo<X86MachineFunctionInfo>();
222 // Print out constants referenced by the function
223 EmitConstantPool(MF.getConstantPool());
225 if (F->hasDLLExportLinkage())
226 DLLExportedFns.insert(Mang->makeNameProper(F->getName(), ""));
228 // Print the 'header' of function
229 emitFunctionHeader(MF);
231 // Emit pre-function debug and/or EH information.
232 if (TAI->doesSupportDebugInformation() || TAI->doesSupportExceptionHandling())
233 DW->BeginFunction(&MF);
235 // Print out code for the function.
236 bool hasAnyRealCode = false;
237 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
239 // Print a label for the basic block.
240 if (!I->pred_empty()) {
241 printBasicBlockLabel(I, true, true);
244 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
246 // Print the assembly for the instruction.
248 hasAnyRealCode = true;
249 printMachineInstruction(II);
253 if (Subtarget->isTargetDarwin() && !hasAnyRealCode) {
254 // If the function is empty, then we need to emit *something*. Otherwise,
255 // the function's label might be associated with something that it wasn't
256 // meant to be associated with. We emit a noop in this situation.
257 // We are assuming inline asms are code.
261 if (TAI->hasDotTypeDotSizeDirective())
262 O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
264 // Emit post-function debug information.
265 if (TAI->doesSupportDebugInformation())
266 DW->EndFunction(&MF);
268 // Print out jump tables referenced by the function.
269 EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
273 // We didn't modify anything.
277 static inline bool shouldPrintGOT(TargetMachine &TM, const X86Subtarget* ST) {
278 return ST->isPICStyleGOT() && TM.getRelocationModel() == Reloc::PIC_;
281 static inline bool shouldPrintPLT(TargetMachine &TM, const X86Subtarget* ST) {
282 return ST->isTargetELF() && TM.getRelocationModel() == Reloc::PIC_ &&
283 (ST->isPICStyleRIPRel() || ST->isPICStyleGOT());
286 static inline bool shouldPrintStub(TargetMachine &TM, const X86Subtarget* ST) {
287 return ST->isPICStyleStub() && TM.getRelocationModel() != Reloc::Static;
290 void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
291 const char *Modifier, bool NotRIPRel) {
292 const MachineOperand &MO = MI->getOperand(OpNo);
293 switch (MO.getType()) {
294 case MachineOperand::MO_Register: {
295 assert(TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
296 "Virtual registers should not make it this far!");
298 unsigned Reg = MO.getReg();
299 if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
300 MVT VT = (strcmp(Modifier+6,"64") == 0) ?
301 MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
302 ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
303 Reg = getX86SubSuperRegister(Reg, VT);
305 O << TRI->getAsmName(Reg);
309 case MachineOperand::MO_Immediate:
311 (strcmp(Modifier, "debug") && strcmp(Modifier, "mem")))
315 case MachineOperand::MO_MachineBasicBlock:
316 printBasicBlockLabel(MO.getMBB());
318 case MachineOperand::MO_JumpTableIndex: {
319 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
320 if (!isMemOp) O << '$';
321 O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << '_'
324 if (TM.getRelocationModel() == Reloc::PIC_) {
325 if (Subtarget->isPICStyleStub())
326 O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
328 else if (Subtarget->isPICStyleGOT())
332 if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
336 case MachineOperand::MO_ConstantPoolIndex: {
337 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
338 if (!isMemOp) O << '$';
339 O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
342 if (TM.getRelocationModel() == Reloc::PIC_) {
343 if (Subtarget->isPICStyleStub())
344 O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
346 else if (Subtarget->isPICStyleGOT())
350 printOffset(MO.getOffset());
352 if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
356 case MachineOperand::MO_GlobalAddress: {
357 bool isCallOp = Modifier && !strcmp(Modifier, "call");
358 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
359 bool needCloseParen = false;
361 const GlobalValue *GV = MO.getGlobal();
362 const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
364 // If GV is an alias then use the aliasee for determining
366 if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV))
367 GVar = dyn_cast_or_null<GlobalVariable>(GA->resolveAliasedGlobal(false));
370 bool isThreadLocal = GVar && GVar->isThreadLocal();
372 std::string Name = Mang->getValueName(GV);
373 decorateName(Name, GV);
375 if (!isMemOp && !isCallOp)
377 else if (Name[0] == '$') {
378 // The name begins with a dollar-sign. In order to avoid having it look
379 // like an integer immediate to the assembler, enclose it in parens.
381 needCloseParen = true;
384 if (shouldPrintStub(TM, Subtarget)) {
385 // Link-once, declaration, or Weakly-linked global variables need
386 // non-lazily-resolved stubs
387 if (GV->isDeclaration() || GV->mayBeOverridden()) {
388 // Dynamically-resolved functions need a stub for the function.
389 if (isCallOp && isa<Function>(GV)) {
390 // Function stubs are no longer needed for Mac OS X 10.5 and up.
391 if (Subtarget->isTargetDarwin() && Subtarget->getDarwinVers() >= 9) {
394 FnStubs.insert(Name);
395 printSuffixedName(Name, "$stub");
397 } else if (GV->hasHiddenVisibility()) {
398 if (!GV->isDeclaration() && !GV->hasCommonLinkage())
399 // Definition is not definitely in the current translation unit.
402 HiddenGVStubs.insert(Name);
403 printSuffixedName(Name, "$non_lazy_ptr");
406 GVStubs.insert(Name);
407 printSuffixedName(Name, "$non_lazy_ptr");
410 if (GV->hasDLLImportLinkage())
415 if (!isCallOp && TM.getRelocationModel() == Reloc::PIC_)
416 O << '-' << getPICLabelString(getFunctionNumber(), TAI, Subtarget);
418 if (GV->hasDLLImportLinkage()) {
424 if (shouldPrintPLT(TM, Subtarget)) {
425 // Assemble call via PLT for externally visible symbols
426 if (!GV->hasHiddenVisibility() && !GV->hasProtectedVisibility() &&
427 !GV->hasLocalLinkage())
430 if (Subtarget->isTargetCygMing() && GV->isDeclaration())
431 // Save function name for later type emission
432 FnStubs.insert(Name);
436 if (GV->hasExternalWeakLinkage())
437 ExtWeakSymbols.insert(GV);
439 printOffset(MO.getOffset());
442 TLSModel::Model model = getTLSModel(GVar, TM.getRelocationModel());
444 case TLSModel::GeneralDynamic:
447 case TLSModel::LocalDynamic:
448 // O << "@TLSLD"; // local dynamic not implemented
451 case TLSModel::InitialExec:
452 if (Subtarget->is64Bit())
453 O << "@TLSGD"; // 64 bit intial exec not implemented
457 case TLSModel::LocalExec:
458 if (Subtarget->is64Bit())
459 O << "@TLSGD"; // 64 bit local exec not implemented
464 assert (0 && "Unknown TLS model");
466 } else if (isMemOp) {
467 if (shouldPrintGOT(TM, Subtarget)) {
468 if (Subtarget->GVRequiresExtraLoad(GV, TM, false))
472 } else if (Subtarget->isPICStyleRIPRel() && !NotRIPRel &&
473 TM.getRelocationModel() != Reloc::Static) {
474 if (Subtarget->GVRequiresExtraLoad(GV, TM, false))
477 if (needCloseParen) {
478 needCloseParen = false;
482 // Use rip when possible to reduce code size, except when
483 // index or base register are also part of the address. e.g.
484 // foo(%rip)(%rcx,%rax,4) is not legal
494 case MachineOperand::MO_ExternalSymbol: {
495 bool isCallOp = Modifier && !strcmp(Modifier, "call");
496 bool needCloseParen = false;
497 std::string Name(TAI->getGlobalPrefix());
498 Name += MO.getSymbolName();
499 // Print function stub suffix unless it's Mac OS X 10.5 and up.
500 if (isCallOp && shouldPrintStub(TM, Subtarget) &&
501 !(Subtarget->isTargetDarwin() && Subtarget->getDarwinVers() >= 9)) {
502 FnStubs.insert(Name);
503 printSuffixedName(Name, "$stub");
508 else if (Name[0] == '$') {
509 // The name begins with a dollar-sign. In order to avoid having it look
510 // like an integer immediate to the assembler, enclose it in parens.
512 needCloseParen = true;
517 if (shouldPrintPLT(TM, Subtarget)) {
518 std::string GOTName(TAI->getGlobalPrefix());
519 GOTName+="_GLOBAL_OFFSET_TABLE_";
521 // HACK! Emit extra offset to PC during printing GOT offset to
522 // compensate for the size of popl instruction. The resulting code
526 // popl %some_register
527 // addl $_GLOBAL_ADDRESS_TABLE_ + [.-piclabel], %some_register
529 << getPICLabelString(getFunctionNumber(), TAI, Subtarget) << ']';
538 if (!isCallOp && Subtarget->isPICStyleRIPRel())
544 O << "<unknown operand type>"; return;
548 void X86ATTAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
549 unsigned char value = MI->getOperand(Op).getImm();
550 assert(value <= 7 && "Invalid ssecc argument!");
552 case 0: O << "eq"; break;
553 case 1: O << "lt"; break;
554 case 2: O << "le"; break;
555 case 3: O << "unord"; break;
556 case 4: O << "neq"; break;
557 case 5: O << "nlt"; break;
558 case 6: O << "nle"; break;
559 case 7: O << "ord"; break;
563 void X86ATTAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
564 const char *Modifier){
565 assert(isMem(MI, Op) && "Invalid memory reference!");
566 MachineOperand BaseReg = MI->getOperand(Op);
567 MachineOperand IndexReg = MI->getOperand(Op+2);
568 const MachineOperand &DispSpec = MI->getOperand(Op+3);
570 bool NotRIPRel = IndexReg.getReg() || BaseReg.getReg();
571 if (DispSpec.isGlobal() ||
574 printOperand(MI, Op+3, "mem", NotRIPRel);
576 int DispVal = DispSpec.getImm();
577 if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg()))
581 if (IndexReg.getReg() || BaseReg.getReg()) {
582 unsigned ScaleVal = MI->getOperand(Op+1).getImm();
583 unsigned BaseRegOperand = 0, IndexRegOperand = 2;
585 // There are cases where we can end up with ESP/RSP in the indexreg slot.
586 // If this happens, swap the base/index register to support assemblers that
587 // don't work when the index is *SP.
588 if (IndexReg.getReg() == X86::ESP || IndexReg.getReg() == X86::RSP) {
589 assert(ScaleVal == 1 && "Scale not supported for stack pointer!");
590 std::swap(BaseReg, IndexReg);
591 std::swap(BaseRegOperand, IndexRegOperand);
595 if (BaseReg.getReg())
596 printOperand(MI, Op+BaseRegOperand, Modifier);
598 if (IndexReg.getReg()) {
600 printOperand(MI, Op+IndexRegOperand, Modifier);
602 O << ',' << ScaleVal;
608 void X86ATTAsmPrinter::printPICJumpTableSetLabel(unsigned uid,
609 const MachineBasicBlock *MBB) const {
610 if (!TAI->getSetDirective())
613 // We don't need .set machinery if we have GOT-style relocations
614 if (Subtarget->isPICStyleGOT())
617 O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
618 << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
619 printBasicBlockLabel(MBB, false, false, false);
620 if (Subtarget->isPICStyleRIPRel())
621 O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
622 << '_' << uid << '\n';
624 O << '-' << getPICLabelString(getFunctionNumber(), TAI, Subtarget) << '\n';
627 void X86ATTAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
628 std::string label = getPICLabelString(getFunctionNumber(), TAI, Subtarget);
629 O << label << '\n' << label << ':';
633 void X86ATTAsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
634 const MachineBasicBlock *MBB,
637 const char *JTEntryDirective = MJTI->getEntrySize() == 4 ?
638 TAI->getData32bitsDirective() : TAI->getData64bitsDirective();
640 O << JTEntryDirective << ' ';
642 if (TM.getRelocationModel() == Reloc::PIC_) {
643 if (Subtarget->isPICStyleRIPRel() || Subtarget->isPICStyleStub()) {
644 O << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
645 << '_' << uid << "_set_" << MBB->getNumber();
646 } else if (Subtarget->isPICStyleGOT()) {
647 printBasicBlockLabel(MBB, false, false, false);
650 assert(0 && "Don't know how to print MBB label for this PIC mode");
652 printBasicBlockLabel(MBB, false, false, false);
655 bool X86ATTAsmPrinter::printAsmMRegister(const MachineOperand &MO,
657 unsigned Reg = MO.getReg();
659 default: return true; // Unknown mode.
660 case 'b': // Print QImode register
661 Reg = getX86SubSuperRegister(Reg, MVT::i8);
663 case 'h': // Print QImode high register
664 Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
666 case 'w': // Print HImode register
667 Reg = getX86SubSuperRegister(Reg, MVT::i16);
669 case 'k': // Print SImode register
670 Reg = getX86SubSuperRegister(Reg, MVT::i32);
672 case 'q': // Print DImode register
673 Reg = getX86SubSuperRegister(Reg, MVT::i64);
677 O << '%'<< TRI->getAsmName(Reg);
681 /// PrintAsmOperand - Print out an operand for an inline asm expression.
683 bool X86ATTAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
685 const char *ExtraCode) {
686 // Does this asm operand have a single letter operand modifier?
687 if (ExtraCode && ExtraCode[0]) {
688 if (ExtraCode[1] != 0) return true; // Unknown modifier.
690 switch (ExtraCode[0]) {
691 default: return true; // Unknown modifier.
692 case 'c': // Don't print "$" before a global var name or constant.
693 printOperand(MI, OpNo, "mem");
695 case 'b': // Print QImode register
696 case 'h': // Print QImode high register
697 case 'w': // Print HImode register
698 case 'k': // Print SImode register
699 case 'q': // Print DImode register
700 if (MI->getOperand(OpNo).isReg())
701 return printAsmMRegister(MI->getOperand(OpNo), ExtraCode[0]);
702 printOperand(MI, OpNo);
705 case 'P': // Don't print @PLT, but do print as memory.
706 printOperand(MI, OpNo, "mem");
711 printOperand(MI, OpNo);
715 bool X86ATTAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
718 const char *ExtraCode) {
719 if (ExtraCode && ExtraCode[0]) {
720 if (ExtraCode[1] != 0) return true; // Unknown modifier.
722 switch (ExtraCode[0]) {
723 default: return true; // Unknown modifier.
724 case 'b': // Print QImode register
725 case 'h': // Print QImode high register
726 case 'w': // Print HImode register
727 case 'k': // Print SImode register
728 case 'q': // Print SImode register
729 // These only apply to registers, ignore on mem.
731 case 'P': // Don't print @PLT, but do print as memory.
732 printOperand(MI, OpNo, "mem");
736 printMemReference(MI, OpNo);
740 /// printMachineInstruction -- Print out a single X86 LLVM instruction MI in
741 /// AT&T syntax to the current output stream.
743 void X86ATTAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
746 // Call the autogenerated instruction printer routines.
747 printInstruction(MI);
751 bool X86ATTAsmPrinter::doInitialization(Module &M) {
753 bool Result = AsmPrinter::doInitialization(M);
755 if (TAI->doesSupportDebugInformation()) {
756 // Let PassManager know we need debug information and relay
757 // the MachineModuleInfo address on to DwarfWriter.
758 // AsmPrinter::doInitialization did this analysis.
759 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
760 DW = getAnalysisIfAvailable<DwarfWriter>();
761 DW->BeginModule(&M, MMI, O, this, TAI);
764 // Darwin wants symbols to be quoted if they have complex names.
765 if (Subtarget->isTargetDarwin())
766 Mang->setUseQuotes(true);
772 void X86ATTAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
773 const TargetData *TD = TM.getTargetData();
775 if (!GVar->hasInitializer())
776 return; // External global require no code
778 // Check to see if this is a special global used by LLVM, if so, emit it.
779 if (EmitSpecialLLVMGlobal(GVar)) {
780 if (Subtarget->isTargetDarwin() &&
781 TM.getRelocationModel() == Reloc::Static) {
782 if (GVar->getName() == "llvm.global_ctors")
783 O << ".reference .constructors_used\n";
784 else if (GVar->getName() == "llvm.global_dtors")
785 O << ".reference .destructors_used\n";
790 std::string name = Mang->getValueName(GVar);
791 Constant *C = GVar->getInitializer();
792 const Type *Type = C->getType();
793 unsigned Size = TD->getTypePaddedSize(Type);
794 unsigned Align = TD->getPreferredAlignmentLog(GVar);
796 printVisibility(name, GVar->getVisibility());
798 if (Subtarget->isTargetELF())
799 O << "\t.type\t" << name << ",@object\n";
801 SwitchToSection(TAI->SectionForGlobal(GVar));
803 if (C->isNullValue() && !GVar->hasSection() &&
804 !(Subtarget->isTargetDarwin() &&
805 TAI->SectionKindForGlobal(GVar) == SectionKind::RODataMergeStr)) {
806 // FIXME: This seems to be pretty darwin-specific
807 if (GVar->hasExternalLinkage()) {
808 if (const char *Directive = TAI->getZeroFillDirective()) {
809 O << "\t.globl " << name << '\n';
810 O << Directive << "__DATA, __common, " << name << ", "
811 << Size << ", " << Align << '\n';
816 if (!GVar->isThreadLocal() &&
817 (GVar->hasLocalLinkage() || GVar->mayBeOverridden())) {
818 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
820 if (TAI->getLCOMMDirective() != NULL) {
821 if (GVar->hasLocalLinkage()) {
822 O << TAI->getLCOMMDirective() << name << ',' << Size;
823 if (Subtarget->isTargetDarwin())
825 } else if (Subtarget->isTargetDarwin() && !GVar->hasCommonLinkage()) {
826 O << "\t.globl " << name << '\n'
827 << TAI->getWeakDefDirective() << name << '\n';
828 EmitAlignment(Align, GVar);
829 O << name << ":\t\t\t\t" << TAI->getCommentString() << ' ';
830 PrintUnmangledNameSafely(GVar, O);
832 EmitGlobalConstant(C);
835 O << TAI->getCOMMDirective() << name << ',' << Size;
836 if (TAI->getCOMMDirectiveTakesAlignment())
837 O << ',' << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
840 if (!Subtarget->isTargetCygMing()) {
841 if (GVar->hasLocalLinkage())
842 O << "\t.local\t" << name << '\n';
844 O << TAI->getCOMMDirective() << name << ',' << Size;
845 if (TAI->getCOMMDirectiveTakesAlignment())
846 O << ',' << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
848 O << "\t\t" << TAI->getCommentString() << ' ';
849 PrintUnmangledNameSafely(GVar, O);
855 switch (GVar->getLinkage()) {
856 case GlobalValue::CommonLinkage:
857 case GlobalValue::LinkOnceLinkage:
858 case GlobalValue::WeakLinkage:
859 if (Subtarget->isTargetDarwin()) {
860 O << "\t.globl " << name << '\n'
861 << TAI->getWeakDefDirective() << name << '\n';
862 } else if (Subtarget->isTargetCygMing()) {
863 O << "\t.globl\t" << name << "\n"
864 "\t.linkonce same_size\n";
866 O << "\t.weak\t" << name << '\n';
869 case GlobalValue::DLLExportLinkage:
870 case GlobalValue::AppendingLinkage:
871 // FIXME: appending linkage variables should go into a section of
872 // their name or something. For now, just emit them as external.
873 case GlobalValue::ExternalLinkage:
874 // If external or appending, declare as a global symbol
875 O << "\t.globl " << name << '\n';
877 case GlobalValue::PrivateLinkage:
878 case GlobalValue::InternalLinkage:
881 assert(0 && "Unknown linkage type!");
884 EmitAlignment(Align, GVar);
885 O << name << ":\t\t\t\t" << TAI->getCommentString() << ' ';
886 PrintUnmangledNameSafely(GVar, O);
888 if (TAI->hasDotTypeDotSizeDirective())
889 O << "\t.size\t" << name << ", " << Size << '\n';
891 EmitGlobalConstant(C);
894 /// printGVStub - Print stub for a global value.
896 void X86ATTAsmPrinter::printGVStub(const char *GV, const char *Prefix) {
897 printSuffixedName(GV, "$non_lazy_ptr", Prefix);
898 O << ":\n\t.indirect_symbol ";
899 if (Prefix) O << Prefix;
900 O << GV << "\n\t.long\t0\n";
903 /// printHiddenGVStub - Print stub for a hidden global value.
905 void X86ATTAsmPrinter::printHiddenGVStub(const char *GV, const char *Prefix) {
907 printSuffixedName(GV, "$non_lazy_ptr", Prefix);
908 if (Prefix) O << Prefix;
909 O << ":\n" << TAI->getData32bitsDirective() << GV << '\n';
913 bool X86ATTAsmPrinter::doFinalization(Module &M) {
914 // Print out module-level global variables here.
915 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
917 printModuleLevelGV(I);
919 if (I->hasDLLExportLinkage())
920 DLLExportedGVs.insert(Mang->makeNameProper(I->getName(),""));
922 // If the global is a extern weak symbol, remember to emit the weak
924 // FIXME: This is rather hacky, since we'll emit references to ALL weak stuff,
925 // not used. But currently it's the only way to deal with extern weak
926 // initializers hidden deep inside constant expressions.
927 if (I->hasExternalWeakLinkage())
928 ExtWeakSymbols.insert(I);
931 for (Module::const_iterator I = M.begin(), E = M.end();
933 // If the global is a extern weak symbol, remember to emit the weak
935 // FIXME: This is rather hacky, since we'll emit references to ALL weak stuff,
936 // not used. But currently it's the only way to deal with extern weak
937 // initializers hidden deep inside constant expressions.
938 if (I->hasExternalWeakLinkage())
939 ExtWeakSymbols.insert(I);
942 // Output linker support code for dllexported globals
943 if (!DLLExportedGVs.empty())
944 SwitchToDataSection(".section .drectve");
946 for (StringSet<>::iterator i = DLLExportedGVs.begin(),
947 e = DLLExportedGVs.end();
949 O << "\t.ascii \" -export:" << i->getKeyData() << ",data\"\n";
951 if (!DLLExportedFns.empty()) {
952 SwitchToDataSection(".section .drectve");
955 for (StringSet<>::iterator i = DLLExportedFns.begin(),
956 e = DLLExportedFns.end();
958 O << "\t.ascii \" -export:" << i->getKeyData() << "\"\n";
960 if (Subtarget->isTargetDarwin()) {
961 SwitchToDataSection("");
963 // Output stubs for dynamically-linked functions
964 for (StringSet<>::iterator i = FnStubs.begin(), e = FnStubs.end();
966 SwitchToDataSection("\t.section __IMPORT,__jump_table,symbol_stubs,"
967 "self_modifying_code+pure_instructions,5", 0);
968 const char *p = i->getKeyData();
969 printSuffixedName(p, "$stub");
971 "\t.indirect_symbol " << p << "\n"
972 "\thlt ; hlt ; hlt ; hlt ; hlt\n";
977 // Print global value stubs.
978 bool InStubSection = false;
979 if (TAI->doesSupportExceptionHandling() && MMI && !Subtarget->is64Bit()) {
980 // Add the (possibly multiple) personalities to the set of global values.
981 // Only referenced functions get into the Personalities list.
982 const std::vector<Function *>& Personalities = MMI->getPersonalities();
983 for (std::vector<Function *>::const_iterator I = Personalities.begin(),
984 E = Personalities.end(); I != E; ++I) {
987 if (!InStubSection) {
989 "\t.section __IMPORT,__pointers,non_lazy_symbol_pointers");
990 InStubSection = true;
992 printGVStub((*I)->getNameStart(), "_");
996 // Output stubs for external and common global variables.
997 if (!InStubSection && !GVStubs.empty())
999 "\t.section __IMPORT,__pointers,non_lazy_symbol_pointers");
1000 for (StringSet<>::iterator i = GVStubs.begin(), e = GVStubs.end();
1002 printGVStub(i->getKeyData());
1004 if (!HiddenGVStubs.empty()) {
1005 SwitchToSection(TAI->getDataSection());
1006 for (StringSet<>::iterator i = HiddenGVStubs.begin(), e = HiddenGVStubs.end();
1008 printHiddenGVStub(i->getKeyData());
1011 // Emit final debug information.
1012 DwarfWriter *DW = getAnalysisIfAvailable<DwarfWriter>();
1015 // Funny Darwin hack: This flag tells the linker that no global symbols
1016 // contain code that falls through to other global symbols (e.g. the obvious
1017 // implementation of multiple entry points). If this doesn't occur, the
1018 // linker can safely perform dead code stripping. Since LLVM never
1019 // generates code that does this, it is always safe to set.
1020 O << "\t.subsections_via_symbols\n";
1021 } else if (Subtarget->isTargetCygMing()) {
1022 // Emit type information for external functions
1023 for (StringSet<>::iterator i = FnStubs.begin(), e = FnStubs.end();
1025 O << "\t.def\t " << i->getKeyData()
1026 << ";\t.scl\t" << COFF::C_EXT
1027 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
1031 // Emit final debug information.
1032 DwarfWriter *DW = getAnalysisIfAvailable<DwarfWriter>();
1034 } else if (Subtarget->isTargetELF()) {
1035 // Emit final debug information.
1036 DwarfWriter *DW = getAnalysisIfAvailable<DwarfWriter>();
1040 return AsmPrinter::doFinalization(M);
1043 // Include the auto-generated portion of the assembly writer.
1044 #include "X86GenAsmWriter.inc"