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 "llvm/CallingConv.h"
23 #include "llvm/DerivedTypes.h"
24 #include "llvm/Module.h"
25 #include "llvm/Type.h"
26 #include "llvm/ADT/Statistic.h"
27 #include "llvm/ADT/StringExtras.h"
28 #include "llvm/Assembly/Writer.h"
29 #include "llvm/MC/MCStreamer.h"
30 #include "llvm/MC/MCSectionMachO.h"
31 #include "llvm/CodeGen/MachineJumpTableInfo.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Support/FormattedStream.h"
35 #include "llvm/Support/Mangler.h"
36 #include "llvm/MC/MCAsmInfo.h"
37 #include "llvm/Target/TargetLoweringObjectFile.h"
38 #include "llvm/Target/TargetOptions.h"
41 STATISTIC(EmittedInsts, "Number of machine instrs printed");
43 static cl::opt<bool> NewAsmPrinter("experimental-asm-printer",
44 cl::Hidden, cl::init(false));
46 //===----------------------------------------------------------------------===//
47 // Primitive Helper Functions.
48 //===----------------------------------------------------------------------===//
50 void X86ATTAsmPrinter::PrintPICBaseSymbol() const {
51 // FIXME: the actual label generated doesn't matter here! Just mangle in
52 // something unique (the function number) with Private prefix.
53 if (Subtarget->isTargetDarwin())
54 O << "\"L" << getFunctionNumber() << "$pb\"";
56 assert(Subtarget->isTargetELF() && "Don't know how to print PIC label!");
57 O << ".Lllvm$" << getFunctionNumber() << ".$piclabel";
61 static X86MachineFunctionInfo calculateFunctionInfo(const Function *F,
62 const TargetData *TD) {
63 X86MachineFunctionInfo Info;
66 switch (F->getCallingConv()) {
67 case CallingConv::X86_StdCall:
68 Info.setDecorationStyle(StdCall);
70 case CallingConv::X86_FastCall:
71 Info.setDecorationStyle(FastCall);
78 for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
79 AI != AE; ++AI, ++argNum) {
80 const Type* Ty = AI->getType();
82 // 'Dereference' type in case of byval parameter attribute
83 if (F->paramHasAttr(argNum, Attribute::ByVal))
84 Ty = cast<PointerType>(Ty)->getElementType();
86 // Size should be aligned to DWORD boundary
87 Size += ((TD->getTypeAllocSize(Ty) + 3)/4)*4;
90 // We're not supporting tooooo huge arguments :)
91 Info.setBytesToPopOnReturn((unsigned int)Size);
95 /// DecorateCygMingName - Query FunctionInfoMap and use this information for
96 /// various name decorations for Cygwin and MingW.
97 void X86ATTAsmPrinter::DecorateCygMingName(std::string &Name,
98 const GlobalValue *GV) {
99 assert(Subtarget->isTargetCygMing() && "This is only for cygwin and mingw");
101 const Function *F = dyn_cast<Function>(GV);
104 // Save function name for later type emission.
105 if (F->isDeclaration())
106 CygMingStubs.insert(Name);
108 // We don't want to decorate non-stdcall or non-fastcall functions right now
109 CallingConv::ID CC = F->getCallingConv();
110 if (CC != CallingConv::X86_StdCall && CC != CallingConv::X86_FastCall)
114 const X86MachineFunctionInfo *Info;
116 FMFInfoMap::const_iterator info_item = FunctionInfoMap.find(F);
117 if (info_item == FunctionInfoMap.end()) {
118 // Calculate apropriate function info and populate map
119 FunctionInfoMap[F] = calculateFunctionInfo(F, TM.getTargetData());
120 Info = &FunctionInfoMap[F];
122 Info = &info_item->second;
125 const FunctionType *FT = F->getFunctionType();
126 switch (Info->getDecorationStyle()) {
130 // "Pure" variadic functions do not receive @0 suffix.
131 if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
132 (FT->getNumParams() == 1 && F->hasStructRetAttr()))
133 Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
136 // "Pure" variadic functions do not receive @0 suffix.
137 if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
138 (FT->getNumParams() == 1 && F->hasStructRetAttr()))
139 Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
141 if (Name[0] == '_') {
148 llvm_unreachable("Unsupported DecorationStyle");
152 void X86ATTAsmPrinter::emitFunctionHeader(const MachineFunction &MF) {
153 unsigned FnAlign = MF.getAlignment();
154 const Function *F = MF.getFunction();
156 if (Subtarget->isTargetCygMing())
157 DecorateCygMingName(CurrentFnName, F);
159 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
160 EmitAlignment(FnAlign, F);
162 switch (F->getLinkage()) {
163 default: llvm_unreachable("Unknown linkage type!");
164 case Function::InternalLinkage: // Symbols default to internal.
165 case Function::PrivateLinkage:
167 case Function::DLLExportLinkage:
168 case Function::ExternalLinkage:
169 O << "\t.globl\t" << CurrentFnName << '\n';
171 case Function::LinkerPrivateLinkage:
172 case Function::LinkOnceAnyLinkage:
173 case Function::LinkOnceODRLinkage:
174 case Function::WeakAnyLinkage:
175 case Function::WeakODRLinkage:
176 if (Subtarget->isTargetDarwin()) {
177 O << "\t.globl\t" << CurrentFnName << '\n';
178 O << MAI->getWeakDefDirective() << CurrentFnName << '\n';
179 } else if (Subtarget->isTargetCygMing()) {
180 O << "\t.globl\t" << CurrentFnName << "\n"
181 "\t.linkonce discard\n";
183 O << "\t.weak\t" << CurrentFnName << '\n';
188 printVisibility(CurrentFnName, F->getVisibility());
190 if (Subtarget->isTargetELF())
191 O << "\t.type\t" << CurrentFnName << ",@function\n";
192 else if (Subtarget->isTargetCygMing()) {
193 O << "\t.def\t " << CurrentFnName
195 (F->hasInternalLinkage() ? COFF::C_STAT : COFF::C_EXT)
196 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
200 O << CurrentFnName << ':';
202 O.PadToColumn(MAI->getCommentColumn());
203 O << MAI->getCommentString() << ' ';
204 WriteAsOperand(O, F, /*PrintType=*/false, F->getParent());
208 // Add some workaround for linkonce linkage on Cygwin\MinGW
209 if (Subtarget->isTargetCygMing() &&
210 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
211 O << "Lllvm$workaround$fake$stub$" << CurrentFnName << ":\n";
214 /// runOnMachineFunction - This uses the printMachineInstruction()
215 /// method to print assembly for each instruction.
217 bool X86ATTAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
218 const Function *F = MF.getFunction();
220 CallingConv::ID CC = F->getCallingConv();
222 SetupMachineFunction(MF);
225 // Populate function information map. Actually, We don't want to populate
226 // non-stdcall or non-fastcall functions' information right now.
227 if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
228 FunctionInfoMap[F] = *MF.getInfo<X86MachineFunctionInfo>();
230 // Print out constants referenced by the function
231 EmitConstantPool(MF.getConstantPool());
233 if (F->hasDLLExportLinkage())
234 DLLExportedFns.insert(Mang->getMangledName(F));
236 // Print the 'header' of function
237 emitFunctionHeader(MF);
239 // Emit pre-function debug and/or EH information.
240 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
241 DW->BeginFunction(&MF);
243 // Print out code for the function.
244 bool hasAnyRealCode = false;
245 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
247 // Print a label for the basic block.
248 if (!VerboseAsm && (I->pred_empty() || I->isOnlyReachableByFallthrough())) {
249 // This is an entry block or a block that's only reachable via a
250 // fallthrough edge. In non-VerboseAsm mode, don't print the label.
252 printBasicBlockLabel(I, true, true, VerboseAsm);
255 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
257 // Print the assembly for the instruction.
259 hasAnyRealCode = true;
260 printMachineInstruction(II);
264 if (Subtarget->isTargetDarwin() && !hasAnyRealCode) {
265 // If the function is empty, then we need to emit *something*. Otherwise,
266 // the function's label might be associated with something that it wasn't
267 // meant to be associated with. We emit a noop in this situation.
268 // We are assuming inline asms are code.
272 if (MAI->hasDotTypeDotSizeDirective())
273 O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << '\n';
275 // Emit post-function debug information.
276 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
277 DW->EndFunction(&MF);
279 // Print out jump tables referenced by the function.
280 EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
282 // We didn't modify anything.
286 /// printSymbolOperand - Print a raw symbol reference operand. This handles
287 /// jump tables, constant pools, global address and external symbols, all of
288 /// which print to a label with various suffixes for relocation types etc.
289 void X86ATTAsmPrinter::printSymbolOperand(const MachineOperand &MO) {
290 switch (MO.getType()) {
291 default: llvm_unreachable("unknown symbol type!");
292 case MachineOperand::MO_JumpTableIndex:
293 O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << '_'
296 case MachineOperand::MO_ConstantPoolIndex:
297 O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
299 printOffset(MO.getOffset());
301 case MachineOperand::MO_GlobalAddress: {
302 const GlobalValue *GV = MO.getGlobal();
304 const char *Suffix = "";
305 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
307 else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
308 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
309 MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
310 Suffix = "$non_lazy_ptr";
312 std::string Name = Mang->getMangledName(GV, Suffix, Suffix[0] != '\0');
313 if (Subtarget->isTargetCygMing())
314 DecorateCygMingName(Name, GV);
316 // Handle dllimport linkage.
317 if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
318 Name = "__imp_" + Name;
320 if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
321 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE)
322 GVStubs[Name] = Mang->getMangledName(GV);
323 else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
324 HiddenGVStubs[Name] = Mang->getMangledName(GV);
325 else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
326 FnStubs[Name] = Mang->getMangledName(GV);
328 // If the name begins with a dollar-sign, enclose it in parens. We do this
329 // to avoid having it look like an integer immediate to the assembler.
331 O << '(' << Name << ')';
335 printOffset(MO.getOffset());
338 case MachineOperand::MO_ExternalSymbol: {
339 std::string Name = Mang->makeNameProper(MO.getSymbolName());
340 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
341 FnStubs[Name+"$stub"] = Name;
345 // If the name begins with a dollar-sign, enclose it in parens. We do this
346 // to avoid having it look like an integer immediate to the assembler.
348 O << '(' << Name << ')';
355 switch (MO.getTargetFlags()) {
357 llvm_unreachable("Unknown target flag on GV operand");
358 case X86II::MO_NO_FLAG: // No flag.
360 case X86II::MO_DARWIN_NONLAZY:
361 case X86II::MO_DLLIMPORT:
362 case X86II::MO_DARWIN_STUB:
363 // These affect the name of the symbol, not any suffix.
365 case X86II::MO_GOT_ABSOLUTE_ADDRESS:
367 PrintPICBaseSymbol();
370 case X86II::MO_PIC_BASE_OFFSET:
371 case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
372 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
374 PrintPICBaseSymbol();
376 case X86II::MO_TLSGD: O << "@TLSGD"; break;
377 case X86II::MO_GOTTPOFF: O << "@GOTTPOFF"; break;
378 case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
379 case X86II::MO_TPOFF: O << "@TPOFF"; break;
380 case X86II::MO_NTPOFF: O << "@NTPOFF"; break;
381 case X86II::MO_GOTPCREL: O << "@GOTPCREL"; break;
382 case X86II::MO_GOT: O << "@GOT"; break;
383 case X86II::MO_GOTOFF: O << "@GOTOFF"; break;
384 case X86II::MO_PLT: O << "@PLT"; break;
388 /// print_pcrel_imm - This is used to print an immediate value that ends up
389 /// being encoded as a pc-relative value. These print slightly differently, for
390 /// example, a $ is not emitted.
391 void X86ATTAsmPrinter::print_pcrel_imm(const MachineInstr *MI, unsigned OpNo) {
392 const MachineOperand &MO = MI->getOperand(OpNo);
393 switch (MO.getType()) {
394 default: llvm_unreachable("Unknown pcrel immediate operand");
395 case MachineOperand::MO_Immediate:
398 case MachineOperand::MO_MachineBasicBlock:
399 printBasicBlockLabel(MO.getMBB(), false, false, false);
401 case MachineOperand::MO_GlobalAddress:
402 case MachineOperand::MO_ExternalSymbol:
403 printSymbolOperand(MO);
410 void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
411 const char *Modifier) {
412 const MachineOperand &MO = MI->getOperand(OpNo);
413 switch (MO.getType()) {
414 default: llvm_unreachable("unknown operand type!");
415 case MachineOperand::MO_Register: {
416 assert(TargetRegisterInfo::isPhysicalRegister(MO.getReg()) &&
417 "Virtual registers should not make it this far!");
419 unsigned Reg = MO.getReg();
420 if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
421 EVT VT = (strcmp(Modifier+6,"64") == 0) ?
422 MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
423 ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
424 Reg = getX86SubSuperRegister(Reg, VT);
426 O << TRI->getAsmName(Reg);
430 case MachineOperand::MO_Immediate:
431 O << '$' << MO.getImm();
434 case MachineOperand::MO_JumpTableIndex:
435 case MachineOperand::MO_ConstantPoolIndex:
436 case MachineOperand::MO_GlobalAddress:
437 case MachineOperand::MO_ExternalSymbol: {
439 printSymbolOperand(MO);
445 void X86ATTAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
446 unsigned char value = MI->getOperand(Op).getImm();
447 assert(value <= 7 && "Invalid ssecc argument!");
449 case 0: O << "eq"; break;
450 case 1: O << "lt"; break;
451 case 2: O << "le"; break;
452 case 3: O << "unord"; break;
453 case 4: O << "neq"; break;
454 case 5: O << "nlt"; break;
455 case 6: O << "nle"; break;
456 case 7: O << "ord"; break;
460 void X86ATTAsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
461 const char *Modifier) {
462 const MachineOperand &BaseReg = MI->getOperand(Op);
463 const MachineOperand &IndexReg = MI->getOperand(Op+2);
464 const MachineOperand &DispSpec = MI->getOperand(Op+3);
466 // If we really don't want to print out (rip), don't.
467 bool HasBaseReg = BaseReg.getReg() != 0;
468 if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
469 BaseReg.getReg() == X86::RIP)
472 // HasParenPart - True if we will print out the () part of the mem ref.
473 bool HasParenPart = IndexReg.getReg() || HasBaseReg;
475 if (DispSpec.isImm()) {
476 int DispVal = DispSpec.getImm();
477 if (DispVal || !HasParenPart)
480 assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
481 DispSpec.isJTI() || DispSpec.isSymbol());
482 printSymbolOperand(MI->getOperand(Op+3));
486 assert(IndexReg.getReg() != X86::ESP &&
487 "X86 doesn't allow scaling by ESP");
491 printOperand(MI, Op, Modifier);
493 if (IndexReg.getReg()) {
495 printOperand(MI, Op+2, Modifier);
496 unsigned ScaleVal = MI->getOperand(Op+1).getImm();
498 O << ',' << ScaleVal;
504 void X86ATTAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
505 const char *Modifier) {
506 assert(isMem(MI, Op) && "Invalid memory reference!");
507 const MachineOperand &Segment = MI->getOperand(Op+4);
508 if (Segment.getReg()) {
509 printOperand(MI, Op+4, Modifier);
512 printLeaMemReference(MI, Op, Modifier);
515 void X86ATTAsmPrinter::printPICJumpTableSetLabel(unsigned uid,
516 const MachineBasicBlock *MBB) const {
517 if (!MAI->getSetDirective())
520 // We don't need .set machinery if we have GOT-style relocations
521 if (Subtarget->isPICStyleGOT())
524 O << MAI->getSetDirective() << ' ' << MAI->getPrivateGlobalPrefix()
525 << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
526 printBasicBlockLabel(MBB, false, false, false);
527 if (Subtarget->isPICStyleRIPRel())
528 O << '-' << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
529 << '_' << uid << '\n';
532 PrintPICBaseSymbol();
538 void X86ATTAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
539 PrintPICBaseSymbol();
541 PrintPICBaseSymbol();
546 void X86ATTAsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
547 const MachineBasicBlock *MBB,
548 unsigned uid) const {
549 const char *JTEntryDirective = MJTI->getEntrySize() == 4 ?
550 MAI->getData32bitsDirective() : MAI->getData64bitsDirective();
552 O << JTEntryDirective << ' ';
554 if (Subtarget->isPICStyleRIPRel() || Subtarget->isPICStyleStubPIC()) {
555 O << MAI->getPrivateGlobalPrefix() << getFunctionNumber()
556 << '_' << uid << "_set_" << MBB->getNumber();
557 } else if (Subtarget->isPICStyleGOT()) {
558 printBasicBlockLabel(MBB, false, false, false);
561 printBasicBlockLabel(MBB, false, false, false);
564 bool X86ATTAsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode) {
565 unsigned Reg = MO.getReg();
567 default: return true; // Unknown mode.
568 case 'b': // Print QImode register
569 Reg = getX86SubSuperRegister(Reg, MVT::i8);
571 case 'h': // Print QImode high register
572 Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
574 case 'w': // Print HImode register
575 Reg = getX86SubSuperRegister(Reg, MVT::i16);
577 case 'k': // Print SImode register
578 Reg = getX86SubSuperRegister(Reg, MVT::i32);
580 case 'q': // Print DImode register
581 Reg = getX86SubSuperRegister(Reg, MVT::i64);
585 O << '%'<< TRI->getAsmName(Reg);
589 /// PrintAsmOperand - Print out an operand for an inline asm expression.
591 bool X86ATTAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
593 const char *ExtraCode) {
594 // Does this asm operand have a single letter operand modifier?
595 if (ExtraCode && ExtraCode[0]) {
596 if (ExtraCode[1] != 0) return true; // Unknown modifier.
598 const MachineOperand &MO = MI->getOperand(OpNo);
600 switch (ExtraCode[0]) {
601 default: return true; // Unknown modifier.
602 case 'a': // This is an address. Currently only 'i' and 'r' are expected.
607 if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
608 printSymbolOperand(MO);
613 printOperand(MI, OpNo);
619 case 'c': // Don't print "$" before a global var name or constant.
622 else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
623 printSymbolOperand(MO);
625 printOperand(MI, OpNo);
628 case 'A': // Print '*' before a register (it must be a register)
631 printOperand(MI, OpNo);
636 case 'b': // Print QImode register
637 case 'h': // Print QImode high register
638 case 'w': // Print HImode register
639 case 'k': // Print SImode register
640 case 'q': // Print DImode register
642 return printAsmMRegister(MO, ExtraCode[0]);
643 printOperand(MI, OpNo);
646 case 'P': // This is the operand of a call, treat specially.
647 print_pcrel_imm(MI, OpNo);
650 case 'n': // Negate the immediate or print a '-' before the operand.
651 // Note: this is a temporary solution. It should be handled target
652 // independently as part of the 'MC' work.
661 printOperand(MI, OpNo);
665 bool X86ATTAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
668 const char *ExtraCode) {
669 if (ExtraCode && ExtraCode[0]) {
670 if (ExtraCode[1] != 0) return true; // Unknown modifier.
672 switch (ExtraCode[0]) {
673 default: return true; // Unknown modifier.
674 case 'b': // Print QImode register
675 case 'h': // Print QImode high register
676 case 'w': // Print HImode register
677 case 'k': // Print SImode register
678 case 'q': // Print SImode register
679 // These only apply to registers, ignore on mem.
681 case 'P': // Don't print @PLT, but do print as memory.
682 printMemReference(MI, OpNo, "no-rip");
686 printMemReference(MI, OpNo);
692 /// printMachineInstruction -- Print out a single X86 LLVM instruction MI in
693 /// AT&T syntax to the current output stream.
695 void X86ATTAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
698 processDebugLoc(MI->getDebugLoc());
700 // Call the autogenerated instruction printer routines.
702 printInstructionThroughMCStreamer(MI);
704 printInstruction(MI);
706 if (VerboseAsm && !MI->getDebugLoc().isUnknown())
711 void X86ATTAsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
712 const TargetData *TD = TM.getTargetData();
714 if (!GVar->hasInitializer())
715 return; // External global require no code
717 // Check to see if this is a special global used by LLVM, if so, emit it.
718 if (EmitSpecialLLVMGlobal(GVar)) {
719 if (Subtarget->isTargetDarwin() &&
720 TM.getRelocationModel() == Reloc::Static) {
721 if (GVar->getName() == "llvm.global_ctors")
722 O << ".reference .constructors_used\n";
723 else if (GVar->getName() == "llvm.global_dtors")
724 O << ".reference .destructors_used\n";
729 std::string name = Mang->getMangledName(GVar);
730 Constant *C = GVar->getInitializer();
731 const Type *Type = C->getType();
732 unsigned Size = TD->getTypeAllocSize(Type);
733 unsigned Align = TD->getPreferredAlignmentLog(GVar);
735 printVisibility(name, GVar->getVisibility());
737 if (Subtarget->isTargetELF())
738 O << "\t.type\t" << name << ",@object\n";
741 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GVar, TM);
742 const MCSection *TheSection =
743 getObjFileLowering().SectionForGlobal(GVar, GVKind, Mang, TM);
744 OutStreamer.SwitchSection(TheSection);
746 // FIXME: get this stuff from section kind flags.
747 if (C->isNullValue() && !GVar->hasSection() &&
748 // Don't put things that should go in the cstring section into "comm".
749 !TheSection->getKind().isMergeableCString()) {
750 if (GVar->hasExternalLinkage()) {
751 if (const char *Directive = MAI->getZeroFillDirective()) {
752 O << "\t.globl " << name << '\n';
753 O << Directive << "__DATA, __common, " << name << ", "
754 << Size << ", " << Align << '\n';
759 if (!GVar->isThreadLocal() &&
760 (GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
761 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
763 if (MAI->getLCOMMDirective() != NULL) {
764 if (GVar->hasLocalLinkage()) {
765 O << MAI->getLCOMMDirective() << name << ',' << Size;
766 if (Subtarget->isTargetDarwin())
768 } else if (Subtarget->isTargetDarwin() && !GVar->hasCommonLinkage()) {
769 O << "\t.globl " << name << '\n'
770 << MAI->getWeakDefDirective() << name << '\n';
771 EmitAlignment(Align, GVar);
774 O.PadToColumn(MAI->getCommentColumn());
775 O << MAI->getCommentString() << ' ';
776 WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
779 EmitGlobalConstant(C);
782 O << MAI->getCOMMDirective() << name << ',' << Size;
783 if (MAI->getCOMMDirectiveTakesAlignment())
784 O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
787 if (!Subtarget->isTargetCygMing()) {
788 if (GVar->hasLocalLinkage())
789 O << "\t.local\t" << name << '\n';
791 O << MAI->getCOMMDirective() << name << ',' << Size;
792 if (MAI->getCOMMDirectiveTakesAlignment())
793 O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
796 O.PadToColumn(MAI->getCommentColumn());
797 O << MAI->getCommentString() << ' ';
798 WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
805 switch (GVar->getLinkage()) {
806 case GlobalValue::CommonLinkage:
807 case GlobalValue::LinkOnceAnyLinkage:
808 case GlobalValue::LinkOnceODRLinkage:
809 case GlobalValue::WeakAnyLinkage:
810 case GlobalValue::WeakODRLinkage:
811 case GlobalValue::LinkerPrivateLinkage:
812 if (Subtarget->isTargetDarwin()) {
813 O << "\t.globl " << name << '\n'
814 << MAI->getWeakDefDirective() << name << '\n';
815 } else if (Subtarget->isTargetCygMing()) {
816 O << "\t.globl\t" << name << "\n"
817 "\t.linkonce same_size\n";
819 O << "\t.weak\t" << name << '\n';
822 case GlobalValue::DLLExportLinkage:
823 case GlobalValue::AppendingLinkage:
824 // FIXME: appending linkage variables should go into a section of
825 // their name or something. For now, just emit them as external.
826 case GlobalValue::ExternalLinkage:
827 // If external or appending, declare as a global symbol
828 O << "\t.globl " << name << '\n';
830 case GlobalValue::PrivateLinkage:
831 case GlobalValue::InternalLinkage:
834 llvm_unreachable("Unknown linkage type!");
837 EmitAlignment(Align, GVar);
840 O.PadToColumn(MAI->getCommentColumn());
841 O << MAI->getCommentString() << ' ';
842 WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
846 EmitGlobalConstant(C);
848 if (MAI->hasDotTypeDotSizeDirective())
849 O << "\t.size\t" << name << ", " << Size << '\n';
852 bool X86ATTAsmPrinter::doFinalization(Module &M) {
853 // Print out module-level global variables here.
854 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
856 if (I->hasDLLExportLinkage())
857 DLLExportedGVs.insert(Mang->getMangledName(I));
860 if (Subtarget->isTargetDarwin()) {
861 // All darwin targets use mach-o.
862 TargetLoweringObjectFileMachO &TLOFMacho =
863 static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
865 // Add the (possibly multiple) personalities to the set of global value
866 // stubs. Only referenced functions get into the Personalities list.
867 if (MAI->doesSupportExceptionHandling() && MMI && !Subtarget->is64Bit()) {
868 const std::vector<Function*> &Personalities = MMI->getPersonalities();
869 for (unsigned i = 0, e = Personalities.size(); i != e; ++i) {
870 if (Personalities[i])
871 GVStubs[Mang->getMangledName(Personalities[i], "$non_lazy_ptr",
872 true /*private label*/)] =
873 Mang->getMangledName(Personalities[i]);
877 // Output stubs for dynamically-linked functions
878 if (!FnStubs.empty()) {
879 const MCSection *TheSection =
880 TLOFMacho.getMachOSection("__IMPORT", "__jump_table",
881 MCSectionMachO::S_SYMBOL_STUBS |
882 MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
883 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
884 5, SectionKind::getMetadata());
885 OutStreamer.SwitchSection(TheSection);
886 for (StringMap<std::string>::iterator I = FnStubs.begin(),
887 E = FnStubs.end(); I != E; ++I)
888 O << I->getKeyData() << ":\n" << "\t.indirect_symbol " << I->second
889 << "\n\thlt ; hlt ; hlt ; hlt ; hlt\n";
893 // Output stubs for external and common global variables.
894 if (!GVStubs.empty()) {
895 const MCSection *TheSection =
896 TLOFMacho.getMachOSection("__IMPORT", "__pointers",
897 MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
898 SectionKind::getMetadata());
899 OutStreamer.SwitchSection(TheSection);
900 for (StringMap<std::string>::iterator I = GVStubs.begin(),
901 E = GVStubs.end(); I != E; ++I)
902 O << I->getKeyData() << ":\n\t.indirect_symbol "
903 << I->second << "\n\t.long\t0\n";
906 if (!HiddenGVStubs.empty()) {
907 OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
909 for (StringMap<std::string>::iterator I = HiddenGVStubs.begin(),
910 E = HiddenGVStubs.end(); I != E; ++I)
911 O << I->getKeyData() << ":\n" << MAI->getData32bitsDirective()
912 << I->second << '\n';
915 // Funny Darwin hack: This flag tells the linker that no global symbols
916 // contain code that falls through to other global symbols (e.g. the obvious
917 // implementation of multiple entry points). If this doesn't occur, the
918 // linker can safely perform dead code stripping. Since LLVM never
919 // generates code that does this, it is always safe to set.
920 O << "\t.subsections_via_symbols\n";
921 } else if (Subtarget->isTargetCygMing()) {
922 // Emit type information for external functions
923 for (StringSet<>::iterator i = CygMingStubs.begin(), e = CygMingStubs.end();
925 O << "\t.def\t " << i->getKeyData()
926 << ";\t.scl\t" << COFF::C_EXT
927 << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
933 // Output linker support code for dllexported globals on windows.
934 if (!DLLExportedGVs.empty() || !DLLExportedFns.empty()) {
935 // dllexport symbols only exist on coff targets.
936 TargetLoweringObjectFileCOFF &TLOFMacho =
937 static_cast<TargetLoweringObjectFileCOFF&>(getObjFileLowering());
939 OutStreamer.SwitchSection(TLOFMacho.getCOFFSection(".section .drectve",true,
940 SectionKind::getMetadata()));
942 for (StringSet<>::iterator i = DLLExportedGVs.begin(),
943 e = DLLExportedGVs.end(); i != e; ++i)
944 O << "\t.ascii \" -export:" << i->getKeyData() << ",data\"\n";
946 for (StringSet<>::iterator i = DLLExportedFns.begin(),
947 e = DLLExportedFns.end();
949 O << "\t.ascii \" -export:" << i->getKeyData() << "\"\n";
952 // Do common shutdown.
953 return AsmPrinter::doFinalization(M);
956 // Include the auto-generated portion of the assembly writer.
957 #include "X86GenAsmWriter.inc"