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 "X86.h"
18 #include "X86COFFMachineModuleInfo.h"
19 #include "X86MachineFunctionInfo.h"
20 #include "X86TargetMachine.h"
21 #include "llvm/ADT/SmallString.h"
22 #include "llvm/Assembly/Writer.h"
23 #include "llvm/CodeGen/MachineJumpTableInfo.h"
24 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
25 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
26 #include "llvm/DebugInfo.h"
27 #include "llvm/IR/CallingConv.h"
28 #include "llvm/IR/DerivedTypes.h"
29 #include "llvm/IR/Module.h"
30 #include "llvm/IR/Type.h"
31 #include "llvm/MC/MCAsmInfo.h"
32 #include "llvm/MC/MCContext.h"
33 #include "llvm/MC/MCExpr.h"
34 #include "llvm/MC/MCSectionMachO.h"
35 #include "llvm/MC/MCStreamer.h"
36 #include "llvm/MC/MCSymbol.h"
37 #include "llvm/Support/COFF.h"
38 #include "llvm/Support/Debug.h"
39 #include "llvm/Support/ErrorHandling.h"
40 #include "llvm/Support/TargetRegistry.h"
41 #include "llvm/Target/Mangler.h"
42 #include "llvm/Target/TargetOptions.h"
43 using namespace llvm;
44
45 //===----------------------------------------------------------------------===//
46 // Primitive Helper Functions.
47 //===----------------------------------------------------------------------===//
48
49 /// runOnMachineFunction - Emit the function body.
50 ///
runOnMachineFunction(MachineFunction & MF)51 bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
52 SetupMachineFunction(MF);
53
54 if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
55 bool Intrn = MF.getFunction()->hasInternalLinkage();
56 OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
57 OutStreamer.EmitCOFFSymbolStorageClass(Intrn ? COFF::IMAGE_SYM_CLASS_STATIC
58 : COFF::IMAGE_SYM_CLASS_EXTERNAL);
59 OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
60 << COFF::SCT_COMPLEX_TYPE_SHIFT);
61 OutStreamer.EndCOFFSymbolDef();
62 }
63
64 // Have common code print out the function header with linkage info etc.
65 EmitFunctionHeader();
66
67 // Emit the rest of the function body.
68 EmitFunctionBody();
69
70 // We didn't modify anything.
71 return false;
72 }
73
74 /// printSymbolOperand - Print a raw symbol reference operand. This handles
75 /// jump tables, constant pools, global address and external symbols, all of
76 /// which print to a label with various suffixes for relocation types etc.
printSymbolOperand(const MachineOperand & MO,raw_ostream & O)77 void X86AsmPrinter::printSymbolOperand(const MachineOperand &MO,
78 raw_ostream &O) {
79 switch (MO.getType()) {
80 default: llvm_unreachable("unknown symbol type!");
81 case MachineOperand::MO_JumpTableIndex:
82 O << *GetJTISymbol(MO.getIndex());
83 break;
84 case MachineOperand::MO_ConstantPoolIndex:
85 O << *GetCPISymbol(MO.getIndex());
86 printOffset(MO.getOffset(), O);
87 break;
88 case MachineOperand::MO_GlobalAddress: {
89 const GlobalValue *GV = MO.getGlobal();
90
91 MCSymbol *GVSym;
92 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB)
93 GVSym = GetSymbolWithGlobalValueBase(GV, "$stub");
94 else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
95 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
96 MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
97 GVSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
98 else
99 GVSym = Mang->getSymbol(GV);
100
101 // Handle dllimport linkage.
102 if (MO.getTargetFlags() == X86II::MO_DLLIMPORT)
103 GVSym = OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName());
104
105 if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
106 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) {
107 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
108 MachineModuleInfoImpl::StubValueTy &StubSym =
109 MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym);
110 if (StubSym.getPointer() == 0)
111 StubSym = MachineModuleInfoImpl::
112 StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
113 } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){
114 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
115 MachineModuleInfoImpl::StubValueTy &StubSym =
116 MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry(Sym);
117 if (StubSym.getPointer() == 0)
118 StubSym = MachineModuleInfoImpl::
119 StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
120 } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
121 MCSymbol *Sym = GetSymbolWithGlobalValueBase(GV, "$stub");
122 MachineModuleInfoImpl::StubValueTy &StubSym =
123 MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
124 if (StubSym.getPointer() == 0)
125 StubSym = MachineModuleInfoImpl::
126 StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
127 }
128
129 // If the name begins with a dollar-sign, enclose it in parens. We do this
130 // to avoid having it look like an integer immediate to the assembler.
131 if (GVSym->getName()[0] != '$')
132 O << *GVSym;
133 else
134 O << '(' << *GVSym << ')';
135 printOffset(MO.getOffset(), O);
136 break;
137 }
138 case MachineOperand::MO_ExternalSymbol: {
139 const MCSymbol *SymToPrint;
140 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) {
141 SmallString<128> TempNameStr;
142 TempNameStr += StringRef(MO.getSymbolName());
143 TempNameStr += StringRef("$stub");
144
145 MCSymbol *Sym = GetExternalSymbolSymbol(TempNameStr.str());
146 MachineModuleInfoImpl::StubValueTy &StubSym =
147 MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym);
148 if (StubSym.getPointer() == 0) {
149 TempNameStr.erase(TempNameStr.end()-5, TempNameStr.end());
150 StubSym = MachineModuleInfoImpl::
151 StubValueTy(OutContext.GetOrCreateSymbol(TempNameStr.str()),
152 true);
153 }
154 SymToPrint = StubSym.getPointer();
155 } else {
156 SymToPrint = GetExternalSymbolSymbol(MO.getSymbolName());
157 }
158
159 // If the name begins with a dollar-sign, enclose it in parens. We do this
160 // to avoid having it look like an integer immediate to the assembler.
161 if (SymToPrint->getName()[0] != '$')
162 O << *SymToPrint;
163 else
164 O << '(' << *SymToPrint << '(';
165 break;
166 }
167 }
168
169 switch (MO.getTargetFlags()) {
170 default:
171 llvm_unreachable("Unknown target flag on GV operand");
172 case X86II::MO_NO_FLAG: // No flag.
173 break;
174 case X86II::MO_DARWIN_NONLAZY:
175 case X86II::MO_DLLIMPORT:
176 case X86II::MO_DARWIN_STUB:
177 // These affect the name of the symbol, not any suffix.
178 break;
179 case X86II::MO_GOT_ABSOLUTE_ADDRESS:
180 O << " + [.-" << *MF->getPICBaseSymbol() << ']';
181 break;
182 case X86II::MO_PIC_BASE_OFFSET:
183 case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
184 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
185 O << '-' << *MF->getPICBaseSymbol();
186 break;
187 case X86II::MO_TLSGD: O << "@TLSGD"; break;
188 case X86II::MO_TLSLD: O << "@TLSLD"; break;
189 case X86II::MO_TLSLDM: O << "@TLSLDM"; 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_DTPOFF: O << "@DTPOFF"; break;
194 case X86II::MO_NTPOFF: O << "@NTPOFF"; break;
195 case X86II::MO_GOTNTPOFF: O << "@GOTNTPOFF"; break;
196 case X86II::MO_GOTPCREL: O << "@GOTPCREL"; break;
197 case X86II::MO_GOT: O << "@GOT"; break;
198 case X86II::MO_GOTOFF: O << "@GOTOFF"; break;
199 case X86II::MO_PLT: O << "@PLT"; break;
200 case X86II::MO_TLVP: O << "@TLVP"; break;
201 case X86II::MO_TLVP_PIC_BASE:
202 O << "@TLVP" << '-' << *MF->getPICBaseSymbol();
203 break;
204 case X86II::MO_SECREL: O << "@SECREL32"; break;
205 }
206 }
207
208 /// printPCRelImm - This is used to print an immediate value that ends up
209 /// being encoded as a pc-relative value. These print slightly differently, for
210 /// example, a $ is not emitted.
printPCRelImm(const MachineInstr * MI,unsigned OpNo,raw_ostream & O)211 void X86AsmPrinter::printPCRelImm(const MachineInstr *MI, unsigned OpNo,
212 raw_ostream &O) {
213 const MachineOperand &MO = MI->getOperand(OpNo);
214 switch (MO.getType()) {
215 default: llvm_unreachable("Unknown pcrel immediate operand");
216 case MachineOperand::MO_Register:
217 // pc-relativeness was handled when computing the value in the reg.
218 printOperand(MI, OpNo, O);
219 return;
220 case MachineOperand::MO_Immediate:
221 O << MO.getImm();
222 return;
223 case MachineOperand::MO_MachineBasicBlock:
224 O << *MO.getMBB()->getSymbol();
225 return;
226 case MachineOperand::MO_GlobalAddress:
227 case MachineOperand::MO_ExternalSymbol:
228 printSymbolOperand(MO, O);
229 return;
230 }
231 }
232
233
printOperand(const MachineInstr * MI,unsigned OpNo,raw_ostream & O,const char * Modifier,unsigned AsmVariant)234 void X86AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
235 raw_ostream &O, const char *Modifier,
236 unsigned AsmVariant) {
237 const MachineOperand &MO = MI->getOperand(OpNo);
238 switch (MO.getType()) {
239 default: llvm_unreachable("unknown operand type!");
240 case MachineOperand::MO_Register: {
241 // FIXME: Enumerating AsmVariant, so we can remove magic number.
242 if (AsmVariant == 0) O << '%';
243 unsigned Reg = MO.getReg();
244 if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
245 MVT::SimpleValueType VT = (strcmp(Modifier+6,"64") == 0) ?
246 MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
247 ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
248 Reg = getX86SubSuperRegister(Reg, VT);
249 }
250 O << X86ATTInstPrinter::getRegisterName(Reg);
251 return;
252 }
253
254 case MachineOperand::MO_Immediate:
255 if (AsmVariant == 0) O << '$';
256 O << MO.getImm();
257 return;
258
259 case MachineOperand::MO_JumpTableIndex:
260 case MachineOperand::MO_ConstantPoolIndex:
261 case MachineOperand::MO_GlobalAddress:
262 case MachineOperand::MO_ExternalSymbol: {
263 if (AsmVariant == 0) O << '$';
264 printSymbolOperand(MO, O);
265 break;
266 }
267 }
268 }
269
printLeaMemReference(const MachineInstr * MI,unsigned Op,raw_ostream & O,const char * Modifier)270 void X86AsmPrinter::printLeaMemReference(const MachineInstr *MI, unsigned Op,
271 raw_ostream &O, const char *Modifier) {
272 const MachineOperand &BaseReg = MI->getOperand(Op);
273 const MachineOperand &IndexReg = MI->getOperand(Op+2);
274 const MachineOperand &DispSpec = MI->getOperand(Op+3);
275
276 // If we really don't want to print out (rip), don't.
277 bool HasBaseReg = BaseReg.getReg() != 0;
278 if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") &&
279 BaseReg.getReg() == X86::RIP)
280 HasBaseReg = false;
281
282 // HasParenPart - True if we will print out the () part of the mem ref.
283 bool HasParenPart = IndexReg.getReg() || HasBaseReg;
284
285 if (DispSpec.isImm()) {
286 int DispVal = DispSpec.getImm();
287 if (DispVal || !HasParenPart)
288 O << DispVal;
289 } else {
290 assert(DispSpec.isGlobal() || DispSpec.isCPI() ||
291 DispSpec.isJTI() || DispSpec.isSymbol());
292 printSymbolOperand(MI->getOperand(Op+3), O);
293 }
294
295 if (Modifier && strcmp(Modifier, "H") == 0)
296 O << "+8";
297
298 if (HasParenPart) {
299 assert(IndexReg.getReg() != X86::ESP &&
300 "X86 doesn't allow scaling by ESP");
301
302 O << '(';
303 if (HasBaseReg)
304 printOperand(MI, Op, O, Modifier);
305
306 if (IndexReg.getReg()) {
307 O << ',';
308 printOperand(MI, Op+2, O, Modifier);
309 unsigned ScaleVal = MI->getOperand(Op+1).getImm();
310 if (ScaleVal != 1)
311 O << ',' << ScaleVal;
312 }
313 O << ')';
314 }
315 }
316
printMemReference(const MachineInstr * MI,unsigned Op,raw_ostream & O,const char * Modifier)317 void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
318 raw_ostream &O, const char *Modifier) {
319 assert(isMem(MI, Op) && "Invalid memory reference!");
320 const MachineOperand &Segment = MI->getOperand(Op+4);
321 if (Segment.getReg()) {
322 printOperand(MI, Op+4, O, Modifier);
323 O << ':';
324 }
325 printLeaMemReference(MI, Op, O, Modifier);
326 }
327
printIntelMemReference(const MachineInstr * MI,unsigned Op,raw_ostream & O,const char * Modifier,unsigned AsmVariant)328 void X86AsmPrinter::printIntelMemReference(const MachineInstr *MI, unsigned Op,
329 raw_ostream &O, const char *Modifier,
330 unsigned AsmVariant){
331 const MachineOperand &BaseReg = MI->getOperand(Op);
332 unsigned ScaleVal = MI->getOperand(Op+1).getImm();
333 const MachineOperand &IndexReg = MI->getOperand(Op+2);
334 const MachineOperand &DispSpec = MI->getOperand(Op+3);
335 const MachineOperand &SegReg = MI->getOperand(Op+4);
336
337 // If this has a segment register, print it.
338 if (SegReg.getReg()) {
339 printOperand(MI, Op+4, O, Modifier, AsmVariant);
340 O << ':';
341 }
342
343 O << '[';
344
345 bool NeedPlus = false;
346 if (BaseReg.getReg()) {
347 printOperand(MI, Op, O, Modifier, AsmVariant);
348 NeedPlus = true;
349 }
350
351 if (IndexReg.getReg()) {
352 if (NeedPlus) O << " + ";
353 if (ScaleVal != 1)
354 O << ScaleVal << '*';
355 printOperand(MI, Op+2, O, Modifier, AsmVariant);
356 NeedPlus = true;
357 }
358
359 if (!DispSpec.isImm()) {
360 if (NeedPlus) O << " + ";
361 printOperand(MI, Op+3, O, Modifier, AsmVariant);
362 } else {
363 int64_t DispVal = DispSpec.getImm();
364 if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg())) {
365 if (NeedPlus) {
366 if (DispVal > 0)
367 O << " + ";
368 else {
369 O << " - ";
370 DispVal = -DispVal;
371 }
372 }
373 O << DispVal;
374 }
375 }
376 O << ']';
377 }
378
printAsmMRegister(const MachineOperand & MO,char Mode,raw_ostream & O)379 bool X86AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode,
380 raw_ostream &O) {
381 unsigned Reg = MO.getReg();
382 switch (Mode) {
383 default: return true; // Unknown mode.
384 case 'b': // Print QImode register
385 Reg = getX86SubSuperRegister(Reg, MVT::i8);
386 break;
387 case 'h': // Print QImode high register
388 Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
389 break;
390 case 'w': // Print HImode register
391 Reg = getX86SubSuperRegister(Reg, MVT::i16);
392 break;
393 case 'k': // Print SImode register
394 Reg = getX86SubSuperRegister(Reg, MVT::i32);
395 break;
396 case 'q': // Print DImode register
397 Reg = getX86SubSuperRegister(Reg, MVT::i64);
398 break;
399 }
400
401 O << '%' << X86ATTInstPrinter::getRegisterName(Reg);
402 return false;
403 }
404
405 /// PrintAsmOperand - Print out an operand for an inline asm expression.
406 ///
PrintAsmOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)407 bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
408 unsigned AsmVariant,
409 const char *ExtraCode, raw_ostream &O) {
410 // Does this asm operand have a single letter operand modifier?
411 if (ExtraCode && ExtraCode[0]) {
412 if (ExtraCode[1] != 0) return true; // Unknown modifier.
413
414 const MachineOperand &MO = MI->getOperand(OpNo);
415
416 switch (ExtraCode[0]) {
417 default:
418 // See if this is a generic print operand
419 return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
420 case 'a': // This is an address. Currently only 'i' and 'r' are expected.
421 if (MO.isImm()) {
422 O << MO.getImm();
423 return false;
424 }
425 if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol()) {
426 printSymbolOperand(MO, O);
427 if (Subtarget->isPICStyleRIPRel())
428 O << "(%rip)";
429 return false;
430 }
431 if (MO.isReg()) {
432 O << '(';
433 printOperand(MI, OpNo, O);
434 O << ')';
435 return false;
436 }
437 return true;
438
439 case 'c': // Don't print "$" before a global var name or constant.
440 if (MO.isImm())
441 O << MO.getImm();
442 else if (MO.isGlobal() || MO.isCPI() || MO.isJTI() || MO.isSymbol())
443 printSymbolOperand(MO, O);
444 else
445 printOperand(MI, OpNo, O);
446 return false;
447
448 case 'A': // Print '*' before a register (it must be a register)
449 if (MO.isReg()) {
450 O << '*';
451 printOperand(MI, OpNo, O);
452 return false;
453 }
454 return true;
455
456 case 'b': // Print QImode register
457 case 'h': // Print QImode high register
458 case 'w': // Print HImode register
459 case 'k': // Print SImode register
460 case 'q': // Print DImode register
461 if (MO.isReg())
462 return printAsmMRegister(MO, ExtraCode[0], O);
463 printOperand(MI, OpNo, O);
464 return false;
465
466 case 'P': // This is the operand of a call, treat specially.
467 printPCRelImm(MI, OpNo, O);
468 return false;
469
470 case 'n': // Negate the immediate or print a '-' before the operand.
471 // Note: this is a temporary solution. It should be handled target
472 // independently as part of the 'MC' work.
473 if (MO.isImm()) {
474 O << -MO.getImm();
475 return false;
476 }
477 O << '-';
478 }
479 }
480
481 printOperand(MI, OpNo, O, /*Modifier*/ 0, AsmVariant);
482 return false;
483 }
484
PrintAsmMemoryOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)485 bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
486 unsigned OpNo, unsigned AsmVariant,
487 const char *ExtraCode,
488 raw_ostream &O) {
489 if (AsmVariant) {
490 printIntelMemReference(MI, OpNo, O);
491 return false;
492 }
493
494 if (ExtraCode && ExtraCode[0]) {
495 if (ExtraCode[1] != 0) return true; // Unknown modifier.
496
497 switch (ExtraCode[0]) {
498 default: return true; // Unknown modifier.
499 case 'b': // Print QImode register
500 case 'h': // Print QImode high register
501 case 'w': // Print HImode register
502 case 'k': // Print SImode register
503 case 'q': // Print SImode register
504 // These only apply to registers, ignore on mem.
505 break;
506 case 'H':
507 printMemReference(MI, OpNo, O, "H");
508 return false;
509 case 'P': // Don't print @PLT, but do print as memory.
510 printMemReference(MI, OpNo, O, "no-rip");
511 return false;
512 }
513 }
514 printMemReference(MI, OpNo, O);
515 return false;
516 }
517
EmitStartOfAsmFile(Module & M)518 void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
519 if (Subtarget->isTargetEnvMacho())
520 OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
521 }
522
523
EmitEndOfAsmFile(Module & M)524 void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
525 if (Subtarget->isTargetEnvMacho()) {
526 // All darwin targets use mach-o.
527 MachineModuleInfoMachO &MMIMacho =
528 MMI->getObjFileInfo<MachineModuleInfoMachO>();
529
530 // Output stubs for dynamically-linked functions.
531 MachineModuleInfoMachO::SymbolListTy Stubs;
532
533 Stubs = MMIMacho.GetFnStubList();
534 if (!Stubs.empty()) {
535 const MCSection *TheSection =
536 OutContext.getMachOSection("__IMPORT", "__jump_table",
537 MCSectionMachO::S_SYMBOL_STUBS |
538 MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
539 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
540 5, SectionKind::getMetadata());
541 OutStreamer.SwitchSection(TheSection);
542
543 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
544 // L_foo$stub:
545 OutStreamer.EmitLabel(Stubs[i].first);
546 // .indirect_symbol _foo
547 OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
548 MCSA_IndirectSymbol);
549 // hlt; hlt; hlt; hlt; hlt hlt = 0xf4.
550 const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
551 OutStreamer.EmitBytes(StringRef(HltInsts, 5));
552 }
553
554 Stubs.clear();
555 OutStreamer.AddBlankLine();
556 }
557
558 // Output stubs for external and common global variables.
559 Stubs = MMIMacho.GetGVStubList();
560 if (!Stubs.empty()) {
561 const MCSection *TheSection =
562 OutContext.getMachOSection("__IMPORT", "__pointers",
563 MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
564 SectionKind::getMetadata());
565 OutStreamer.SwitchSection(TheSection);
566
567 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
568 // L_foo$non_lazy_ptr:
569 OutStreamer.EmitLabel(Stubs[i].first);
570 // .indirect_symbol _foo
571 MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
572 OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
573 MCSA_IndirectSymbol);
574 // .long 0
575 if (MCSym.getInt())
576 // External to current translation unit.
577 OutStreamer.EmitIntValue(0, 4/*size*/);
578 else
579 // Internal to current translation unit.
580 //
581 // When we place the LSDA into the TEXT section, the type info
582 // pointers need to be indirect and pc-rel. We accomplish this by
583 // using NLPs. However, sometimes the types are local to the file. So
584 // we need to fill in the value for the NLP in those cases.
585 OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
586 OutContext), 4/*size*/);
587 }
588 Stubs.clear();
589 OutStreamer.AddBlankLine();
590 }
591
592 Stubs = MMIMacho.GetHiddenGVStubList();
593 if (!Stubs.empty()) {
594 OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
595 EmitAlignment(2);
596
597 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
598 // L_foo$non_lazy_ptr:
599 OutStreamer.EmitLabel(Stubs[i].first);
600 // .long _foo
601 OutStreamer.EmitValue(MCSymbolRefExpr::
602 Create(Stubs[i].second.getPointer(),
603 OutContext), 4/*size*/);
604 }
605 Stubs.clear();
606 OutStreamer.AddBlankLine();
607 }
608
609 // Funny Darwin hack: This flag tells the linker that no global symbols
610 // contain code that falls through to other global symbols (e.g. the obvious
611 // implementation of multiple entry points). If this doesn't occur, the
612 // linker can safely perform dead code stripping. Since LLVM never
613 // generates code that does this, it is always safe to set.
614 OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
615 }
616
617 if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
618 MMI->usesVAFloatArgument()) {
619 StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
620 MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
621 OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
622 }
623
624 if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
625 X86COFFMachineModuleInfo &COFFMMI =
626 MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
627
628 // Emit type information for external functions
629 typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
630 for (externals_iterator I = COFFMMI.externals_begin(),
631 E = COFFMMI.externals_end();
632 I != E; ++I) {
633 OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
634 OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
635 OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
636 << COFF::SCT_COMPLEX_TYPE_SHIFT);
637 OutStreamer.EndCOFFSymbolDef();
638 }
639
640 // Necessary for dllexport support
641 std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;
642
643 const TargetLoweringObjectFileCOFF &TLOFCOFF =
644 static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());
645
646 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
647 if (I->hasDLLExportLinkage())
648 DLLExportedFns.push_back(Mang->getSymbol(I));
649
650 for (Module::const_global_iterator I = M.global_begin(),
651 E = M.global_end(); I != E; ++I)
652 if (I->hasDLLExportLinkage())
653 DLLExportedGlobals.push_back(Mang->getSymbol(I));
654
655 // Output linker support code for dllexported globals on windows.
656 if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
657 OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
658 SmallString<128> name;
659 for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
660 if (Subtarget->isTargetWindows())
661 name = " /EXPORT:";
662 else
663 name = " -export:";
664 name += DLLExportedGlobals[i]->getName();
665 if (Subtarget->isTargetWindows())
666 name += ",DATA";
667 else
668 name += ",data";
669 OutStreamer.EmitBytes(name);
670 }
671
672 for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
673 if (Subtarget->isTargetWindows())
674 name = " /EXPORT:";
675 else
676 name = " -export:";
677 name += DLLExportedFns[i]->getName();
678 OutStreamer.EmitBytes(name);
679 }
680 }
681 }
682
683 if (Subtarget->isTargetELF()) {
684 const TargetLoweringObjectFileELF &TLOFELF =
685 static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());
686
687 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
688
689 // Output stubs for external and common global variables.
690 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
691 if (!Stubs.empty()) {
692 OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
693 const DataLayout *TD = TM.getDataLayout();
694
695 for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
696 OutStreamer.EmitLabel(Stubs[i].first);
697 OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
698 TD->getPointerSize());
699 }
700 Stubs.clear();
701 }
702 }
703 }
704
705 //===----------------------------------------------------------------------===//
706 // Target Registry Stuff
707 //===----------------------------------------------------------------------===//
708
709 // Force static initialization.
LLVMInitializeX86AsmPrinter()710 extern "C" void LLVMInitializeX86AsmPrinter() {
711 RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target);
712 RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target);
713 }
714