AsmPrinter.cpp revision af25768415eb280affde138e75273a8d5263041e
1//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===// 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 implements the AsmPrinter class. 11// 12//===----------------------------------------------------------------------===// 13 14#define DEBUG_TYPE "asm-printer" 15#include "llvm/CodeGen/AsmPrinter.h" 16#include "DwarfDebug.h" 17#include "DwarfException.h" 18#include "llvm/Module.h" 19#include "llvm/CodeGen/GCMetadataPrinter.h" 20#include "llvm/CodeGen/MachineConstantPool.h" 21#include "llvm/CodeGen/MachineFrameInfo.h" 22#include "llvm/CodeGen/MachineFunction.h" 23#include "llvm/CodeGen/MachineJumpTableInfo.h" 24#include "llvm/CodeGen/MachineLoopInfo.h" 25#include "llvm/CodeGen/MachineModuleInfo.h" 26#include "llvm/Analysis/ConstantFolding.h" 27#include "llvm/Analysis/DebugInfo.h" 28#include "llvm/MC/MCAsmInfo.h" 29#include "llvm/MC/MCContext.h" 30#include "llvm/MC/MCExpr.h" 31#include "llvm/MC/MCInst.h" 32#include "llvm/MC/MCSection.h" 33#include "llvm/MC/MCStreamer.h" 34#include "llvm/MC/MCSymbol.h" 35#include "llvm/Target/Mangler.h" 36#include "llvm/Target/TargetAsmInfo.h" 37#include "llvm/Target/TargetData.h" 38#include "llvm/Target/TargetInstrInfo.h" 39#include "llvm/Target/TargetLowering.h" 40#include "llvm/Target/TargetLoweringObjectFile.h" 41#include "llvm/Target/TargetOptions.h" 42#include "llvm/Target/TargetRegisterInfo.h" 43#include "llvm/Assembly/Writer.h" 44#include "llvm/ADT/SmallString.h" 45#include "llvm/ADT/Statistic.h" 46#include "llvm/Support/ErrorHandling.h" 47#include "llvm/Support/Format.h" 48#include "llvm/Support/Timer.h" 49using namespace llvm; 50 51static const char *DWARFGroupName = "DWARF Emission"; 52static const char *DbgTimerName = "DWARF Debug Writer"; 53static const char *EHTimerName = "DWARF Exception Writer"; 54 55STATISTIC(EmittedInsts, "Number of machine instrs printed"); 56 57char AsmPrinter::ID = 0; 58 59typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type; 60static gcp_map_type &getGCMap(void *&P) { 61 if (P == 0) 62 P = new gcp_map_type(); 63 return *(gcp_map_type*)P; 64} 65 66 67/// getGVAlignmentLog2 - Return the alignment to use for the specified global 68/// value in log2 form. This rounds up to the preferred alignment if possible 69/// and legal. 70static unsigned getGVAlignmentLog2(const GlobalValue *GV, const TargetData &TD, 71 unsigned InBits = 0) { 72 unsigned NumBits = 0; 73 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV)) 74 NumBits = TD.getPreferredAlignmentLog(GVar); 75 76 // If InBits is specified, round it to it. 77 if (InBits > NumBits) 78 NumBits = InBits; 79 80 // If the GV has a specified alignment, take it into account. 81 if (GV->getAlignment() == 0) 82 return NumBits; 83 84 unsigned GVAlign = Log2_32(GV->getAlignment()); 85 86 // If the GVAlign is larger than NumBits, or if we are required to obey 87 // NumBits because the GV has an assigned section, obey it. 88 if (GVAlign > NumBits || GV->hasSection()) 89 NumBits = GVAlign; 90 return NumBits; 91} 92 93 94 95 96AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer) 97 : MachineFunctionPass(ID), 98 TM(tm), MAI(tm.getMCAsmInfo()), 99 OutContext(Streamer.getContext()), 100 OutStreamer(Streamer), 101 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) { 102 DD = 0; DE = 0; MMI = 0; LI = 0; 103 GCMetadataPrinters = 0; 104 VerboseAsm = Streamer.isVerboseAsm(); 105} 106 107AsmPrinter::~AsmPrinter() { 108 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized"); 109 110 if (GCMetadataPrinters != 0) { 111 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 112 113 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I) 114 delete I->second; 115 delete &GCMap; 116 GCMetadataPrinters = 0; 117 } 118 119 delete &OutStreamer; 120} 121 122/// getFunctionNumber - Return a unique ID for the current function. 123/// 124unsigned AsmPrinter::getFunctionNumber() const { 125 return MF->getFunctionNumber(); 126} 127 128const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const { 129 return TM.getTargetLowering()->getObjFileLowering(); 130} 131 132 133/// getTargetData - Return information about data layout. 134const TargetData &AsmPrinter::getTargetData() const { 135 return *TM.getTargetData(); 136} 137 138/// getCurrentSection() - Return the current section we are emitting to. 139const MCSection *AsmPrinter::getCurrentSection() const { 140 return OutStreamer.getCurrentSection(); 141} 142 143 144 145void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const { 146 AU.setPreservesAll(); 147 MachineFunctionPass::getAnalysisUsage(AU); 148 AU.addRequired<MachineModuleInfo>(); 149 AU.addRequired<GCModuleInfo>(); 150 if (isVerbose()) 151 AU.addRequired<MachineLoopInfo>(); 152} 153 154bool AsmPrinter::doInitialization(Module &M) { 155 MMI = getAnalysisIfAvailable<MachineModuleInfo>(); 156 MMI->AnalyzeModule(M); 157 158 // Initialize TargetLoweringObjectFile. 159 const_cast<TargetLoweringObjectFile&>(getObjFileLowering()) 160 .Initialize(OutContext, TM); 161 162 Mang = new Mangler(OutContext, *TM.getTargetData()); 163 164 // Allow the target to emit any magic that it wants at the start of the file. 165 EmitStartOfAsmFile(M); 166 167 // Very minimal debug info. It is ignored if we emit actual debug info. If we 168 // don't, this at least helps the user find where a global came from. 169 if (MAI->hasSingleParameterDotFile()) { 170 // .file "foo.c" 171 OutStreamer.EmitFileDirective(M.getModuleIdentifier()); 172 } 173 174 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 175 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 176 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I) 177 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I)) 178 MP->beginAssembly(*this); 179 180 // Emit module-level inline asm if it exists. 181 if (!M.getModuleInlineAsm().empty()) { 182 OutStreamer.AddComment("Start of file scope inline assembly"); 183 OutStreamer.AddBlankLine(); 184 EmitInlineAsm(M.getModuleInlineAsm()+"\n"); 185 OutStreamer.AddComment("End of file scope inline assembly"); 186 OutStreamer.AddBlankLine(); 187 } 188 189 if (MAI->doesSupportDebugInformation()) 190 DD = new DwarfDebug(this, &M); 191 192 switch (MAI->getExceptionHandlingType()) { 193 case ExceptionHandling::None: 194 return false; 195 case ExceptionHandling::SjLj: 196 DE = new DwarfSjLjException(this); 197 return false; 198 case ExceptionHandling::DwarfCFI: 199 DE = new DwarfCFIException(this); 200 return false; 201 case ExceptionHandling::ARM: 202 DE = new ARMException(this); 203 return false; 204 } 205 206 llvm_unreachable("Unknown exception type."); 207} 208 209void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const { 210 switch ((GlobalValue::LinkageTypes)Linkage) { 211 case GlobalValue::CommonLinkage: 212 case GlobalValue::LinkOnceAnyLinkage: 213 case GlobalValue::LinkOnceODRLinkage: 214 case GlobalValue::WeakAnyLinkage: 215 case GlobalValue::WeakODRLinkage: 216 case GlobalValue::LinkerPrivateWeakLinkage: 217 case GlobalValue::LinkerPrivateWeakDefAutoLinkage: 218 if (MAI->getWeakDefDirective() != 0) { 219 // .globl _foo 220 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 221 222 if ((GlobalValue::LinkageTypes)Linkage != 223 GlobalValue::LinkerPrivateWeakDefAutoLinkage) 224 // .weak_definition _foo 225 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition); 226 else 227 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate); 228 } else if (MAI->getLinkOnceDirective() != 0) { 229 // .globl _foo 230 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 231 //NOTE: linkonce is handled by the section the symbol was assigned to. 232 } else { 233 // .weak _foo 234 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak); 235 } 236 break; 237 case GlobalValue::DLLExportLinkage: 238 case GlobalValue::AppendingLinkage: 239 // FIXME: appending linkage variables should go into a section of 240 // their name or something. For now, just emit them as external. 241 case GlobalValue::ExternalLinkage: 242 // If external or appending, declare as a global symbol. 243 // .globl _foo 244 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 245 break; 246 case GlobalValue::PrivateLinkage: 247 case GlobalValue::InternalLinkage: 248 case GlobalValue::LinkerPrivateLinkage: 249 break; 250 default: 251 llvm_unreachable("Unknown linkage type!"); 252 } 253} 254 255 256/// EmitGlobalVariable - Emit the specified global variable to the .s file. 257void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) { 258 if (GV->hasInitializer()) { 259 // Check to see if this is a special global used by LLVM, if so, emit it. 260 if (EmitSpecialLLVMGlobal(GV)) 261 return; 262 263 if (isVerbose()) { 264 WriteAsOperand(OutStreamer.GetCommentOS(), GV, 265 /*PrintType=*/false, GV->getParent()); 266 OutStreamer.GetCommentOS() << '\n'; 267 } 268 } 269 270 MCSymbol *GVSym = Mang->getSymbol(GV); 271 EmitVisibility(GVSym, GV->getVisibility()); 272 273 if (!GV->hasInitializer()) // External globals require no extra code. 274 return; 275 276 if (MAI->hasDotTypeDotSizeDirective()) 277 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject); 278 279 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM); 280 281 const TargetData *TD = TM.getTargetData(); 282 uint64_t Size = TD->getTypeAllocSize(GV->getType()->getElementType()); 283 284 // If the alignment is specified, we *must* obey it. Overaligning a global 285 // with a specified alignment is a prompt way to break globals emitted to 286 // sections and expected to be contiguous (e.g. ObjC metadata). 287 unsigned AlignLog = getGVAlignmentLog2(GV, *TD); 288 289 // Handle common and BSS local symbols (.lcomm). 290 if (GVKind.isCommon() || GVKind.isBSSLocal()) { 291 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. 292 293 // Handle common symbols. 294 if (GVKind.isCommon()) { 295 unsigned Align = 1 << AlignLog; 296 if (!getObjFileLowering().getCommDirectiveSupportsAlignment()) 297 Align = 0; 298 299 // .comm _foo, 42, 4 300 OutStreamer.EmitCommonSymbol(GVSym, Size, Align); 301 return; 302 } 303 304 // Handle local BSS symbols. 305 if (MAI->hasMachoZeroFillDirective()) { 306 const MCSection *TheSection = 307 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 308 // .zerofill __DATA, __bss, _foo, 400, 5 309 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog); 310 return; 311 } 312 313 if (MAI->hasLCOMMDirective()) { 314 // .lcomm _foo, 42 315 OutStreamer.EmitLocalCommonSymbol(GVSym, Size); 316 return; 317 } 318 319 unsigned Align = 1 << AlignLog; 320 if (!getObjFileLowering().getCommDirectiveSupportsAlignment()) 321 Align = 0; 322 323 // .local _foo 324 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local); 325 // .comm _foo, 42, 4 326 OutStreamer.EmitCommonSymbol(GVSym, Size, Align); 327 return; 328 } 329 330 const MCSection *TheSection = 331 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 332 333 // Handle the zerofill directive on darwin, which is a special form of BSS 334 // emission. 335 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) { 336 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined. 337 338 // .globl _foo 339 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 340 // .zerofill __DATA, __common, _foo, 400, 5 341 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog); 342 return; 343 } 344 345 // Handle thread local data for mach-o which requires us to output an 346 // additional structure of data and mangle the original symbol so that we 347 // can reference it later. 348 // 349 // TODO: This should become an "emit thread local global" method on TLOF. 350 // All of this macho specific stuff should be sunk down into TLOFMachO and 351 // stuff like "TLSExtraDataSection" should no longer be part of the parent 352 // TLOF class. This will also make it more obvious that stuff like 353 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho 354 // specific code. 355 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) { 356 // Emit the .tbss symbol 357 MCSymbol *MangSym = 358 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init")); 359 360 if (GVKind.isThreadBSS()) 361 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog); 362 else if (GVKind.isThreadData()) { 363 OutStreamer.SwitchSection(TheSection); 364 365 EmitAlignment(AlignLog, GV); 366 OutStreamer.EmitLabel(MangSym); 367 368 EmitGlobalConstant(GV->getInitializer()); 369 } 370 371 OutStreamer.AddBlankLine(); 372 373 // Emit the variable struct for the runtime. 374 const MCSection *TLVSect 375 = getObjFileLowering().getTLSExtraDataSection(); 376 377 OutStreamer.SwitchSection(TLVSect); 378 // Emit the linkage here. 379 EmitLinkage(GV->getLinkage(), GVSym); 380 OutStreamer.EmitLabel(GVSym); 381 382 // Three pointers in size: 383 // - __tlv_bootstrap - used to make sure support exists 384 // - spare pointer, used when mapped by the runtime 385 // - pointer to mangled symbol above with initializer 386 unsigned PtrSize = TD->getPointerSizeInBits()/8; 387 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"), 388 PtrSize, 0); 389 OutStreamer.EmitIntValue(0, PtrSize, 0); 390 OutStreamer.EmitSymbolValue(MangSym, PtrSize, 0); 391 392 OutStreamer.AddBlankLine(); 393 return; 394 } 395 396 OutStreamer.SwitchSection(TheSection); 397 398 EmitLinkage(GV->getLinkage(), GVSym); 399 EmitAlignment(AlignLog, GV); 400 401 OutStreamer.EmitLabel(GVSym); 402 403 EmitGlobalConstant(GV->getInitializer()); 404 405 if (MAI->hasDotTypeDotSizeDirective()) 406 // .size foo, 42 407 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext)); 408 409 OutStreamer.AddBlankLine(); 410} 411 412/// EmitFunctionHeader - This method emits the header for the current 413/// function. 414void AsmPrinter::EmitFunctionHeader() { 415 // Print out constants referenced by the function 416 EmitConstantPool(); 417 418 // Print the 'header' of function. 419 const Function *F = MF->getFunction(); 420 421 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM)); 422 EmitVisibility(CurrentFnSym, F->getVisibility()); 423 424 EmitLinkage(F->getLinkage(), CurrentFnSym); 425 EmitAlignment(MF->getAlignment(), F); 426 427 if (MAI->hasDotTypeDotSizeDirective()) 428 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction); 429 430 if (isVerbose()) { 431 WriteAsOperand(OutStreamer.GetCommentOS(), F, 432 /*PrintType=*/false, F->getParent()); 433 OutStreamer.GetCommentOS() << '\n'; 434 } 435 436 // Emit the CurrentFnSym. This is a virtual function to allow targets to 437 // do their wild and crazy things as required. 438 EmitFunctionEntryLabel(); 439 440 // If the function had address-taken blocks that got deleted, then we have 441 // references to the dangling symbols. Emit them at the start of the function 442 // so that we don't get references to undefined symbols. 443 std::vector<MCSymbol*> DeadBlockSyms; 444 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms); 445 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) { 446 OutStreamer.AddComment("Address taken block that was later removed"); 447 OutStreamer.EmitLabel(DeadBlockSyms[i]); 448 } 449 450 // Add some workaround for linkonce linkage on Cygwin\MinGW. 451 if (MAI->getLinkOnceDirective() != 0 && 452 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) { 453 // FIXME: What is this? 454 MCSymbol *FakeStub = 455 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+ 456 CurrentFnSym->getName()); 457 OutStreamer.EmitLabel(FakeStub); 458 } 459 460 // Emit pre-function debug and/or EH information. 461 if (DE) { 462 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 463 DE->BeginFunction(MF); 464 } 465 if (DD) { 466 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 467 DD->beginFunction(MF); 468 } 469} 470 471/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the 472/// function. This can be overridden by targets as required to do custom stuff. 473void AsmPrinter::EmitFunctionEntryLabel() { 474 // The function label could have already been emitted if two symbols end up 475 // conflicting due to asm renaming. Detect this and emit an error. 476 if (CurrentFnSym->isUndefined()) 477 return OutStreamer.EmitLabel(CurrentFnSym); 478 479 report_fatal_error("'" + Twine(CurrentFnSym->getName()) + 480 "' label emitted multiple times to assembly file"); 481} 482 483 484/// EmitComments - Pretty-print comments for instructions. 485static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) { 486 const MachineFunction *MF = MI.getParent()->getParent(); 487 const TargetMachine &TM = MF->getTarget(); 488 489 // Check for spills and reloads 490 int FI; 491 492 const MachineFrameInfo *FrameInfo = MF->getFrameInfo(); 493 494 // We assume a single instruction only has a spill or reload, not 495 // both. 496 const MachineMemOperand *MMO; 497 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) { 498 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 499 MMO = *MI.memoperands_begin(); 500 CommentOS << MMO->getSize() << "-byte Reload\n"; 501 } 502 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) { 503 if (FrameInfo->isSpillSlotObjectIndex(FI)) 504 CommentOS << MMO->getSize() << "-byte Folded Reload\n"; 505 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) { 506 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 507 MMO = *MI.memoperands_begin(); 508 CommentOS << MMO->getSize() << "-byte Spill\n"; 509 } 510 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) { 511 if (FrameInfo->isSpillSlotObjectIndex(FI)) 512 CommentOS << MMO->getSize() << "-byte Folded Spill\n"; 513 } 514 515 // Check for spill-induced copies 516 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse)) 517 CommentOS << " Reload Reuse\n"; 518} 519 520/// EmitImplicitDef - This method emits the specified machine instruction 521/// that is an implicit def. 522static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) { 523 unsigned RegNo = MI->getOperand(0).getReg(); 524 AP.OutStreamer.AddComment(Twine("implicit-def: ") + 525 AP.TM.getRegisterInfo()->getName(RegNo)); 526 AP.OutStreamer.AddBlankLine(); 527} 528 529static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) { 530 std::string Str = "kill:"; 531 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 532 const MachineOperand &Op = MI->getOperand(i); 533 assert(Op.isReg() && "KILL instruction must have only register operands"); 534 Str += ' '; 535 Str += AP.TM.getRegisterInfo()->getName(Op.getReg()); 536 Str += (Op.isDef() ? "<def>" : "<kill>"); 537 } 538 AP.OutStreamer.AddComment(Str); 539 AP.OutStreamer.AddBlankLine(); 540} 541 542/// EmitDebugValueComment - This method handles the target-independent form 543/// of DBG_VALUE, returning true if it was able to do so. A false return 544/// means the target will need to handle MI in EmitInstruction. 545static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) { 546 // This code handles only the 3-operand target-independent form. 547 if (MI->getNumOperands() != 3) 548 return false; 549 550 SmallString<128> Str; 551 raw_svector_ostream OS(Str); 552 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: "; 553 554 // cast away const; DIetc do not take const operands for some reason. 555 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata())); 556 if (V.getContext().isSubprogram()) 557 OS << DISubprogram(V.getContext()).getDisplayName() << ":"; 558 OS << V.getName() << " <- "; 559 560 // Register or immediate value. Register 0 means undef. 561 if (MI->getOperand(0).isFPImm()) { 562 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF()); 563 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) { 564 OS << (double)APF.convertToFloat(); 565 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) { 566 OS << APF.convertToDouble(); 567 } else { 568 // There is no good way to print long double. Convert a copy to 569 // double. Ah well, it's only a comment. 570 bool ignored; 571 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 572 &ignored); 573 OS << "(long double) " << APF.convertToDouble(); 574 } 575 } else if (MI->getOperand(0).isImm()) { 576 OS << MI->getOperand(0).getImm(); 577 } else { 578 assert(MI->getOperand(0).isReg() && "Unknown operand type"); 579 if (MI->getOperand(0).getReg() == 0) { 580 // Suppress offset, it is not meaningful here. 581 OS << "undef"; 582 // NOTE: Want this comment at start of line, don't emit with AddComment. 583 AP.OutStreamer.EmitRawText(OS.str()); 584 return true; 585 } 586 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg()); 587 } 588 589 OS << '+' << MI->getOperand(1).getImm(); 590 // NOTE: Want this comment at start of line, don't emit with AddComment. 591 AP.OutStreamer.EmitRawText(OS.str()); 592 return true; 593} 594 595bool AsmPrinter::needsCFIMoves() { 596 if (UnwindTablesMandatory) 597 return true; 598 599 if (MMI->hasDebugInfo()) 600 return true; 601 602 if (MF->getFunction()->doesNotThrow()) 603 return false; 604 605 return true; 606} 607 608void AsmPrinter::emitPrologLabel(const MachineInstr &MI) { 609 MCSymbol *Label = MI.getOperand(0).getMCSymbol(); 610 611 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI) 612 return; 613 614 if (!needsCFIMoves()) 615 return; 616 617 MachineModuleInfo &MMI = MF->getMMI(); 618 std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 619 bool FoundOne = false; 620 (void)FoundOne; 621 for (std::vector<MachineMove>::iterator I = Moves.begin(), 622 E = Moves.end(); I != E; ++I) { 623 if (I->getLabel() == Label) { 624 EmitCFIFrameMove(*I); 625 FoundOne = true; 626 } 627 } 628 assert(FoundOne); 629} 630 631/// EmitFunctionBody - This method emits the body and trailer for a 632/// function. 633void AsmPrinter::EmitFunctionBody() { 634 // Emit target-specific gunk before the function body. 635 EmitFunctionBodyStart(); 636 637 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo(); 638 639 // Print out code for the function. 640 bool HasAnyRealCode = false; 641 const MachineInstr *LastMI = 0; 642 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 643 I != E; ++I) { 644 // Print a label for the basic block. 645 EmitBasicBlockStart(I); 646 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 647 II != IE; ++II) { 648 LastMI = II; 649 650 // Print the assembly for the instruction. 651 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() && 652 !II->isDebugValue()) { 653 HasAnyRealCode = true; 654 ++EmittedInsts; 655 } 656 657 if (ShouldPrintDebugScopes) { 658 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 659 DD->beginInstruction(II); 660 } 661 662 if (isVerbose()) 663 EmitComments(*II, OutStreamer.GetCommentOS()); 664 665 switch (II->getOpcode()) { 666 case TargetOpcode::PROLOG_LABEL: 667 emitPrologLabel(*II); 668 break; 669 670 case TargetOpcode::EH_LABEL: 671 case TargetOpcode::GC_LABEL: 672 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol()); 673 break; 674 case TargetOpcode::INLINEASM: 675 EmitInlineAsm(II); 676 break; 677 case TargetOpcode::DBG_VALUE: 678 if (isVerbose()) { 679 if (!EmitDebugValueComment(II, *this)) 680 EmitInstruction(II); 681 } 682 break; 683 case TargetOpcode::IMPLICIT_DEF: 684 if (isVerbose()) EmitImplicitDef(II, *this); 685 break; 686 case TargetOpcode::KILL: 687 if (isVerbose()) EmitKill(II, *this); 688 break; 689 default: 690 if (!TM.hasMCUseLoc()) 691 MCLineEntry::Make(&OutStreamer, getCurrentSection()); 692 693 EmitInstruction(II); 694 break; 695 } 696 697 if (ShouldPrintDebugScopes) { 698 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 699 DD->endInstruction(II); 700 } 701 } 702 } 703 704 // If the last instruction was a prolog label, then we have a situation where 705 // we emitted a prolog but no function body. This results in the ending prolog 706 // label equaling the end of function label and an invalid "row" in the 707 // FDE. We need to emit a noop in this situation so that the FDE's rows are 708 // valid. 709 bool RequiresNoop = LastMI && LastMI->isPrologLabel(); 710 711 // If the function is empty and the object file uses .subsections_via_symbols, 712 // then we need to emit *something* to the function body to prevent the 713 // labels from collapsing together. Just emit a noop. 714 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) { 715 MCInst Noop; 716 TM.getInstrInfo()->getNoopForMachoTarget(Noop); 717 if (Noop.getOpcode()) { 718 OutStreamer.AddComment("avoids zero-length function"); 719 OutStreamer.EmitInstruction(Noop); 720 } else // Target not mc-ized yet. 721 OutStreamer.EmitRawText(StringRef("\tnop\n")); 722 } 723 724 // Emit target-specific gunk after the function body. 725 EmitFunctionBodyEnd(); 726 727 // If the target wants a .size directive for the size of the function, emit 728 // it. 729 if (MAI->hasDotTypeDotSizeDirective()) { 730 // Create a symbol for the end of function, so we can get the size as 731 // difference between the function label and the temp label. 732 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol(); 733 OutStreamer.EmitLabel(FnEndLabel); 734 735 const MCExpr *SizeExp = 736 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext), 737 MCSymbolRefExpr::Create(CurrentFnSym, OutContext), 738 OutContext); 739 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp); 740 } 741 742 // Emit post-function debug information. 743 if (DD) { 744 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 745 DD->endFunction(MF); 746 } 747 if (DE) { 748 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 749 DE->EndFunction(); 750 } 751 MMI->EndFunction(); 752 753 // Print out jump tables referenced by the function. 754 EmitJumpTableInfo(); 755 756 OutStreamer.AddBlankLine(); 757} 758 759/// getDebugValueLocation - Get location information encoded by DBG_VALUE 760/// operands. 761MachineLocation AsmPrinter:: 762getDebugValueLocation(const MachineInstr *MI) const { 763 // Target specific DBG_VALUE instructions are handled by each target. 764 return MachineLocation(); 765} 766 767/// getDwarfRegOpSize - get size required to emit given machine location using 768/// dwarf encoding. 769unsigned AsmPrinter::getDwarfRegOpSize(const MachineLocation &MLoc) const { 770 const TargetRegisterInfo *RI = TM.getRegisterInfo(); 771 unsigned DWReg = RI->getDwarfRegNum(MLoc.getReg(), false); 772 if (int Offset = MLoc.getOffset()) { 773 // If the value is at a certain offset from frame register then 774 // use DW_OP_breg. 775 if (DWReg < 32) 776 return 1 + MCAsmInfo::getSLEB128Size(Offset); 777 else 778 return 1 + MCAsmInfo::getULEB128Size(MLoc.getReg()) 779 + MCAsmInfo::getSLEB128Size(Offset); 780 } 781 if (DWReg < 32) 782 return 1; 783 784 return 1 + MCAsmInfo::getULEB128Size(DWReg); 785} 786 787/// EmitDwarfRegOp - Emit dwarf register operation. 788void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const { 789 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 790 unsigned Reg = TRI->getDwarfRegNum(MLoc.getReg(), false); 791 if (int Offset = MLoc.getOffset()) { 792 if (Reg < 32) { 793 OutStreamer.AddComment( 794 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg)); 795 EmitInt8(dwarf::DW_OP_breg0 + Reg); 796 } else { 797 OutStreamer.AddComment("DW_OP_bregx"); 798 EmitInt8(dwarf::DW_OP_bregx); 799 OutStreamer.AddComment(Twine(Reg)); 800 EmitULEB128(Reg); 801 } 802 EmitSLEB128(Offset); 803 } else { 804 if (Reg < 32) { 805 OutStreamer.AddComment( 806 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg)); 807 EmitInt8(dwarf::DW_OP_reg0 + Reg); 808 } else { 809 OutStreamer.AddComment("DW_OP_regx"); 810 EmitInt8(dwarf::DW_OP_regx); 811 OutStreamer.AddComment(Twine(Reg)); 812 EmitULEB128(Reg); 813 } 814 } 815} 816 817bool AsmPrinter::doFinalization(Module &M) { 818 // Emit global variables. 819 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 820 I != E; ++I) 821 EmitGlobalVariable(I); 822 823 // Emit visibility info for declarations 824 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 825 const Function &F = *I; 826 if (!F.isDeclaration()) 827 continue; 828 GlobalValue::VisibilityTypes V = F.getVisibility(); 829 if (V == GlobalValue::DefaultVisibility) 830 continue; 831 832 MCSymbol *Name = Mang->getSymbol(&F); 833 EmitVisibility(Name, V, false); 834 } 835 836 // Finalize debug and EH information. 837 if (DE) { 838 { 839 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 840 DE->EndModule(); 841 } 842 delete DE; DE = 0; 843 } 844 if (DD) { 845 { 846 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 847 DD->endModule(); 848 } 849 delete DD; DD = 0; 850 } 851 852 // If the target wants to know about weak references, print them all. 853 if (MAI->getWeakRefDirective()) { 854 // FIXME: This is not lazy, it would be nice to only print weak references 855 // to stuff that is actually used. Note that doing so would require targets 856 // to notice uses in operands (due to constant exprs etc). This should 857 // happen with the MC stuff eventually. 858 859 // Print out module-level global variables here. 860 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 861 I != E; ++I) { 862 if (!I->hasExternalWeakLinkage()) continue; 863 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 864 } 865 866 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 867 if (!I->hasExternalWeakLinkage()) continue; 868 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 869 } 870 } 871 872 if (MAI->hasSetDirective()) { 873 OutStreamer.AddBlankLine(); 874 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end(); 875 I != E; ++I) { 876 MCSymbol *Name = Mang->getSymbol(I); 877 878 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal()); 879 MCSymbol *Target = Mang->getSymbol(GV); 880 881 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective()) 882 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global); 883 else if (I->hasWeakLinkage()) 884 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference); 885 else 886 assert(I->hasLocalLinkage() && "Invalid alias linkage"); 887 888 EmitVisibility(Name, I->getVisibility()); 889 890 // Emit the directives as assignments aka .set: 891 OutStreamer.EmitAssignment(Name, 892 MCSymbolRefExpr::Create(Target, OutContext)); 893 } 894 } 895 896 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 897 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 898 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; ) 899 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I)) 900 MP->finishAssembly(*this); 901 902 // If we don't have any trampolines, then we don't require stack memory 903 // to be executable. Some targets have a directive to declare this. 904 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline"); 905 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty()) 906 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext)) 907 OutStreamer.SwitchSection(S); 908 909 // Allow the target to emit any magic that it wants at the end of the file, 910 // after everything else has gone out. 911 EmitEndOfAsmFile(M); 912 913 delete Mang; Mang = 0; 914 MMI = 0; 915 916 OutStreamer.Finish(); 917 return false; 918} 919 920void AsmPrinter::SetupMachineFunction(MachineFunction &MF) { 921 this->MF = &MF; 922 // Get the function symbol. 923 CurrentFnSym = Mang->getSymbol(MF.getFunction()); 924 925 if (isVerbose()) 926 LI = &getAnalysis<MachineLoopInfo>(); 927} 928 929namespace { 930 // SectionCPs - Keep track the alignment, constpool entries per Section. 931 struct SectionCPs { 932 const MCSection *S; 933 unsigned Alignment; 934 SmallVector<unsigned, 4> CPEs; 935 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {} 936 }; 937} 938 939/// EmitConstantPool - Print to the current output stream assembly 940/// representations of the constants in the constant pool MCP. This is 941/// used to print out constants which have been "spilled to memory" by 942/// the code generator. 943/// 944void AsmPrinter::EmitConstantPool() { 945 const MachineConstantPool *MCP = MF->getConstantPool(); 946 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants(); 947 if (CP.empty()) return; 948 949 // Calculate sections for constant pool entries. We collect entries to go into 950 // the same section together to reduce amount of section switch statements. 951 SmallVector<SectionCPs, 4> CPSections; 952 for (unsigned i = 0, e = CP.size(); i != e; ++i) { 953 const MachineConstantPoolEntry &CPE = CP[i]; 954 unsigned Align = CPE.getAlignment(); 955 956 SectionKind Kind; 957 switch (CPE.getRelocationInfo()) { 958 default: llvm_unreachable("Unknown section kind"); 959 case 2: Kind = SectionKind::getReadOnlyWithRel(); break; 960 case 1: 961 Kind = SectionKind::getReadOnlyWithRelLocal(); 962 break; 963 case 0: 964 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) { 965 case 4: Kind = SectionKind::getMergeableConst4(); break; 966 case 8: Kind = SectionKind::getMergeableConst8(); break; 967 case 16: Kind = SectionKind::getMergeableConst16();break; 968 default: Kind = SectionKind::getMergeableConst(); break; 969 } 970 } 971 972 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind); 973 974 // The number of sections are small, just do a linear search from the 975 // last section to the first. 976 bool Found = false; 977 unsigned SecIdx = CPSections.size(); 978 while (SecIdx != 0) { 979 if (CPSections[--SecIdx].S == S) { 980 Found = true; 981 break; 982 } 983 } 984 if (!Found) { 985 SecIdx = CPSections.size(); 986 CPSections.push_back(SectionCPs(S, Align)); 987 } 988 989 if (Align > CPSections[SecIdx].Alignment) 990 CPSections[SecIdx].Alignment = Align; 991 CPSections[SecIdx].CPEs.push_back(i); 992 } 993 994 // Now print stuff into the calculated sections. 995 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) { 996 OutStreamer.SwitchSection(CPSections[i].S); 997 EmitAlignment(Log2_32(CPSections[i].Alignment)); 998 999 unsigned Offset = 0; 1000 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) { 1001 unsigned CPI = CPSections[i].CPEs[j]; 1002 MachineConstantPoolEntry CPE = CP[CPI]; 1003 1004 // Emit inter-object padding for alignment. 1005 unsigned AlignMask = CPE.getAlignment() - 1; 1006 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask; 1007 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/); 1008 1009 const Type *Ty = CPE.getType(); 1010 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty); 1011 OutStreamer.EmitLabel(GetCPISymbol(CPI)); 1012 1013 if (CPE.isMachineConstantPoolEntry()) 1014 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal); 1015 else 1016 EmitGlobalConstant(CPE.Val.ConstVal); 1017 } 1018 } 1019} 1020 1021/// EmitJumpTableInfo - Print assembly representations of the jump tables used 1022/// by the current function to the current output stream. 1023/// 1024void AsmPrinter::EmitJumpTableInfo() { 1025 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 1026 if (MJTI == 0) return; 1027 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return; 1028 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 1029 if (JT.empty()) return; 1030 1031 // Pick the directive to use to print the jump table entries, and switch to 1032 // the appropriate section. 1033 const Function *F = MF->getFunction(); 1034 bool JTInDiffSection = false; 1035 if (// In PIC mode, we need to emit the jump table to the same section as the 1036 // function body itself, otherwise the label differences won't make sense. 1037 // FIXME: Need a better predicate for this: what about custom entries? 1038 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 || 1039 // We should also do if the section name is NULL or function is declared 1040 // in discardable section 1041 // FIXME: this isn't the right predicate, should be based on the MCSection 1042 // for the function. 1043 F->isWeakForLinker()) { 1044 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM)); 1045 } else { 1046 // Otherwise, drop it in the readonly section. 1047 const MCSection *ReadOnlySection = 1048 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly()); 1049 OutStreamer.SwitchSection(ReadOnlySection); 1050 JTInDiffSection = true; 1051 } 1052 1053 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData()))); 1054 1055 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) { 1056 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 1057 1058 // If this jump table was deleted, ignore it. 1059 if (JTBBs.empty()) continue; 1060 1061 // For the EK_LabelDifference32 entry, if the target supports .set, emit a 1062 // .set directive for each unique entry. This reduces the number of 1063 // relocations the assembler will generate for the jump table. 1064 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 && 1065 MAI->hasSetDirective()) { 1066 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets; 1067 const TargetLowering *TLI = TM.getTargetLowering(); 1068 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext); 1069 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) { 1070 const MachineBasicBlock *MBB = JTBBs[ii]; 1071 if (!EmittedSets.insert(MBB)) continue; 1072 1073 // .set LJTSet, LBB32-base 1074 const MCExpr *LHS = 1075 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1076 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()), 1077 MCBinaryExpr::CreateSub(LHS, Base, OutContext)); 1078 } 1079 } 1080 1081 // On some targets (e.g. Darwin) we want to emit two consecutive labels 1082 // before each jump table. The first label is never referenced, but tells 1083 // the assembler and linker the extents of the jump table object. The 1084 // second label is actually referenced by the code. 1085 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0]) 1086 // FIXME: This doesn't have to have any specific name, just any randomly 1087 // named and numbered 'l' label would work. Simplify GetJTISymbol. 1088 OutStreamer.EmitLabel(GetJTISymbol(JTI, true)); 1089 1090 OutStreamer.EmitLabel(GetJTISymbol(JTI)); 1091 1092 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) 1093 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI); 1094 } 1095} 1096 1097/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the 1098/// current stream. 1099void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI, 1100 const MachineBasicBlock *MBB, 1101 unsigned UID) const { 1102 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block"); 1103 const MCExpr *Value = 0; 1104 switch (MJTI->getEntryKind()) { 1105 case MachineJumpTableInfo::EK_Inline: 1106 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break; 1107 case MachineJumpTableInfo::EK_Custom32: 1108 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID, 1109 OutContext); 1110 break; 1111 case MachineJumpTableInfo::EK_BlockAddress: 1112 // EK_BlockAddress - Each entry is a plain address of block, e.g.: 1113 // .word LBB123 1114 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1115 break; 1116 case MachineJumpTableInfo::EK_GPRel32BlockAddress: { 1117 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded 1118 // with a relocation as gp-relative, e.g.: 1119 // .gprel32 LBB123 1120 MCSymbol *MBBSym = MBB->getSymbol(); 1121 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1122 return; 1123 } 1124 1125 case MachineJumpTableInfo::EK_LabelDifference32: { 1126 // EK_LabelDifference32 - Each entry is the address of the block minus 1127 // the address of the jump table. This is used for PIC jump tables where 1128 // gprel32 is not supported. e.g.: 1129 // .word LBB123 - LJTI1_2 1130 // If the .set directive is supported, this is emitted as: 1131 // .set L4_5_set_123, LBB123 - LJTI1_2 1132 // .word L4_5_set_123 1133 1134 // If we have emitted set directives for the jump table entries, print 1135 // them rather than the entries themselves. If we're emitting PIC, then 1136 // emit the table entries as differences between two text section labels. 1137 if (MAI->hasSetDirective()) { 1138 // If we used .set, reference the .set's symbol. 1139 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()), 1140 OutContext); 1141 break; 1142 } 1143 // Otherwise, use the difference as the jump table entry. 1144 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1145 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext); 1146 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext); 1147 break; 1148 } 1149 } 1150 1151 assert(Value && "Unknown entry kind!"); 1152 1153 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData()); 1154 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0); 1155} 1156 1157 1158/// EmitSpecialLLVMGlobal - Check to see if the specified global is a 1159/// special global used by LLVM. If so, emit it and return true, otherwise 1160/// do nothing and return false. 1161bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) { 1162 if (GV->getName() == "llvm.used") { 1163 if (MAI->hasNoDeadStrip()) // No need to emit this at all. 1164 EmitLLVMUsedList(GV->getInitializer()); 1165 return true; 1166 } 1167 1168 // Ignore debug and non-emitted data. This handles llvm.compiler.used. 1169 if (GV->getSection() == "llvm.metadata" || 1170 GV->hasAvailableExternallyLinkage()) 1171 return true; 1172 1173 if (!GV->hasAppendingLinkage()) return false; 1174 1175 assert(GV->hasInitializer() && "Not a special LLVM global!"); 1176 1177 const TargetData *TD = TM.getTargetData(); 1178 unsigned Align = Log2_32(TD->getPointerPrefAlignment()); 1179 if (GV->getName() == "llvm.global_ctors") { 1180 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection()); 1181 EmitAlignment(Align); 1182 EmitXXStructorList(GV->getInitializer()); 1183 1184 if (TM.getRelocationModel() == Reloc::Static && 1185 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1186 StringRef Sym(".constructors_used"); 1187 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1188 MCSA_Reference); 1189 } 1190 return true; 1191 } 1192 1193 if (GV->getName() == "llvm.global_dtors") { 1194 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection()); 1195 EmitAlignment(Align); 1196 EmitXXStructorList(GV->getInitializer()); 1197 1198 if (TM.getRelocationModel() == Reloc::Static && 1199 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1200 StringRef Sym(".destructors_used"); 1201 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1202 MCSA_Reference); 1203 } 1204 return true; 1205 } 1206 1207 return false; 1208} 1209 1210/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each 1211/// global in the specified llvm.used list for which emitUsedDirectiveFor 1212/// is true, as being used with this directive. 1213void AsmPrinter::EmitLLVMUsedList(Constant *List) { 1214 // Should be an array of 'i8*'. 1215 ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1216 if (InitList == 0) return; 1217 1218 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1219 const GlobalValue *GV = 1220 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts()); 1221 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang)) 1222 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip); 1223 } 1224} 1225 1226/// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the 1227/// function pointers, ignoring the init priority. 1228void AsmPrinter::EmitXXStructorList(Constant *List) { 1229 // Should be an array of '{ int, void ()* }' structs. The first value is the 1230 // init priority, which we ignore. 1231 if (!isa<ConstantArray>(List)) return; 1232 ConstantArray *InitList = cast<ConstantArray>(List); 1233 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 1234 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){ 1235 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs. 1236 1237 if (CS->getOperand(1)->isNullValue()) 1238 return; // Found a null terminator, exit printing. 1239 // Emit the function pointer. 1240 EmitGlobalConstant(CS->getOperand(1)); 1241 } 1242} 1243 1244//===--------------------------------------------------------------------===// 1245// Emission and print routines 1246// 1247 1248/// EmitInt8 - Emit a byte directive and value. 1249/// 1250void AsmPrinter::EmitInt8(int Value) const { 1251 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/); 1252} 1253 1254/// EmitInt16 - Emit a short directive and value. 1255/// 1256void AsmPrinter::EmitInt16(int Value) const { 1257 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/); 1258} 1259 1260/// EmitInt32 - Emit a long directive and value. 1261/// 1262void AsmPrinter::EmitInt32(int Value) const { 1263 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/); 1264} 1265 1266/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size 1267/// in bytes of the directive is specified by Size and Hi/Lo specify the 1268/// labels. This implicitly uses .set if it is available. 1269void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, 1270 unsigned Size) const { 1271 // Get the Hi-Lo expression. 1272 const MCExpr *Diff = 1273 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext), 1274 MCSymbolRefExpr::Create(Lo, OutContext), 1275 OutContext); 1276 1277 if (!MAI->hasSetDirective()) { 1278 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/); 1279 return; 1280 } 1281 1282 // Otherwise, emit with .set (aka assignment). 1283 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1284 OutStreamer.EmitAssignment(SetLabel, Diff); 1285 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/); 1286} 1287 1288/// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo" 1289/// where the size in bytes of the directive is specified by Size and Hi/Lo 1290/// specify the labels. This implicitly uses .set if it is available. 1291void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset, 1292 const MCSymbol *Lo, unsigned Size) 1293 const { 1294 1295 // Emit Hi+Offset - Lo 1296 // Get the Hi+Offset expression. 1297 const MCExpr *Plus = 1298 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext), 1299 MCConstantExpr::Create(Offset, OutContext), 1300 OutContext); 1301 1302 // Get the Hi+Offset-Lo expression. 1303 const MCExpr *Diff = 1304 MCBinaryExpr::CreateSub(Plus, 1305 MCSymbolRefExpr::Create(Lo, OutContext), 1306 OutContext); 1307 1308 if (!MAI->hasSetDirective()) 1309 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/); 1310 else { 1311 // Otherwise, emit with .set (aka assignment). 1312 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1313 OutStreamer.EmitAssignment(SetLabel, Diff); 1314 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/); 1315 } 1316} 1317 1318/// EmitLabelPlusOffset - Emit something like ".long Label+Offset" 1319/// where the size in bytes of the directive is specified by Size and Label 1320/// specifies the label. This implicitly uses .set if it is available. 1321void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset, 1322 unsigned Size) 1323 const { 1324 1325 // Emit Label+Offset 1326 const MCExpr *Plus = 1327 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Label, OutContext), 1328 MCConstantExpr::Create(Offset, OutContext), 1329 OutContext); 1330 1331 OutStreamer.EmitValue(Plus, 4, 0/*AddrSpace*/); 1332} 1333 1334 1335//===----------------------------------------------------------------------===// 1336 1337// EmitAlignment - Emit an alignment directive to the specified power of 1338// two boundary. For example, if you pass in 3 here, you will get an 8 1339// byte alignment. If a global value is specified, and if that global has 1340// an explicit alignment requested, it will override the alignment request 1341// if required for correctness. 1342// 1343void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const { 1344 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getTargetData(), NumBits); 1345 1346 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment. 1347 1348 if (getCurrentSection()->getKind().isText()) 1349 OutStreamer.EmitCodeAlignment(1 << NumBits); 1350 else 1351 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0); 1352} 1353 1354//===----------------------------------------------------------------------===// 1355// Constant emission. 1356//===----------------------------------------------------------------------===// 1357 1358/// LowerConstant - Lower the specified LLVM Constant to an MCExpr. 1359/// 1360static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) { 1361 MCContext &Ctx = AP.OutContext; 1362 1363 if (CV->isNullValue() || isa<UndefValue>(CV)) 1364 return MCConstantExpr::Create(0, Ctx); 1365 1366 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) 1367 return MCConstantExpr::Create(CI->getZExtValue(), Ctx); 1368 1369 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 1370 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx); 1371 1372 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV)) 1373 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx); 1374 1375 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV); 1376 if (CE == 0) { 1377 llvm_unreachable("Unknown constant value to lower!"); 1378 return MCConstantExpr::Create(0, Ctx); 1379 } 1380 1381 switch (CE->getOpcode()) { 1382 default: 1383 // If the code isn't optimized, there may be outstanding folding 1384 // opportunities. Attempt to fold the expression using TargetData as a 1385 // last resort before giving up. 1386 if (Constant *C = 1387 ConstantFoldConstantExpression(CE, AP.TM.getTargetData())) 1388 if (C != CE) 1389 return LowerConstant(C, AP); 1390 1391 // Otherwise report the problem to the user. 1392 { 1393 std::string S; 1394 raw_string_ostream OS(S); 1395 OS << "Unsupported expression in static initializer: "; 1396 WriteAsOperand(OS, CE, /*PrintType=*/false, 1397 !AP.MF ? 0 : AP.MF->getFunction()->getParent()); 1398 report_fatal_error(OS.str()); 1399 } 1400 return MCConstantExpr::Create(0, Ctx); 1401 case Instruction::GetElementPtr: { 1402 const TargetData &TD = *AP.TM.getTargetData(); 1403 // Generate a symbolic expression for the byte address 1404 const Constant *PtrVal = CE->getOperand(0); 1405 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end()); 1406 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0], 1407 IdxVec.size()); 1408 1409 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP); 1410 if (Offset == 0) 1411 return Base; 1412 1413 // Truncate/sext the offset to the pointer size. 1414 if (TD.getPointerSizeInBits() != 64) { 1415 int SExtAmount = 64-TD.getPointerSizeInBits(); 1416 Offset = (Offset << SExtAmount) >> SExtAmount; 1417 } 1418 1419 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx), 1420 Ctx); 1421 } 1422 1423 case Instruction::Trunc: 1424 // We emit the value and depend on the assembler to truncate the generated 1425 // expression properly. This is important for differences between 1426 // blockaddress labels. Since the two labels are in the same function, it 1427 // is reasonable to treat their delta as a 32-bit value. 1428 // FALL THROUGH. 1429 case Instruction::BitCast: 1430 return LowerConstant(CE->getOperand(0), AP); 1431 1432 case Instruction::IntToPtr: { 1433 const TargetData &TD = *AP.TM.getTargetData(); 1434 // Handle casts to pointers by changing them into casts to the appropriate 1435 // integer type. This promotes constant folding and simplifies this code. 1436 Constant *Op = CE->getOperand(0); 1437 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()), 1438 false/*ZExt*/); 1439 return LowerConstant(Op, AP); 1440 } 1441 1442 case Instruction::PtrToInt: { 1443 const TargetData &TD = *AP.TM.getTargetData(); 1444 // Support only foldable casts to/from pointers that can be eliminated by 1445 // changing the pointer to the appropriately sized integer type. 1446 Constant *Op = CE->getOperand(0); 1447 const Type *Ty = CE->getType(); 1448 1449 const MCExpr *OpExpr = LowerConstant(Op, AP); 1450 1451 // We can emit the pointer value into this slot if the slot is an 1452 // integer slot equal to the size of the pointer. 1453 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType())) 1454 return OpExpr; 1455 1456 // Otherwise the pointer is smaller than the resultant integer, mask off 1457 // the high bits so we are sure to get a proper truncation if the input is 1458 // a constant expr. 1459 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType()); 1460 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx); 1461 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx); 1462 } 1463 1464 // The MC library also has a right-shift operator, but it isn't consistently 1465 // signed or unsigned between different targets. 1466 case Instruction::Add: 1467 case Instruction::Sub: 1468 case Instruction::Mul: 1469 case Instruction::SDiv: 1470 case Instruction::SRem: 1471 case Instruction::Shl: 1472 case Instruction::And: 1473 case Instruction::Or: 1474 case Instruction::Xor: { 1475 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP); 1476 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP); 1477 switch (CE->getOpcode()) { 1478 default: llvm_unreachable("Unknown binary operator constant cast expr"); 1479 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx); 1480 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx); 1481 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx); 1482 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx); 1483 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx); 1484 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx); 1485 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx); 1486 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx); 1487 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx); 1488 } 1489 } 1490 } 1491} 1492 1493static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace, 1494 AsmPrinter &AP); 1495 1496static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace, 1497 AsmPrinter &AP) { 1498 if (AddrSpace != 0 || !CA->isString()) { 1499 // Not a string. Print the values in successive locations 1500 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1501 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP); 1502 return; 1503 } 1504 1505 // Otherwise, it can be emitted as .ascii. 1506 SmallVector<char, 128> TmpVec; 1507 TmpVec.reserve(CA->getNumOperands()); 1508 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1509 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue()); 1510 1511 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace); 1512} 1513 1514static void EmitGlobalConstantVector(const ConstantVector *CV, 1515 unsigned AddrSpace, AsmPrinter &AP) { 1516 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i) 1517 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP); 1518} 1519 1520static void EmitGlobalConstantStruct(const ConstantStruct *CS, 1521 unsigned AddrSpace, AsmPrinter &AP) { 1522 // Print the fields in successive locations. Pad to align if needed! 1523 const TargetData *TD = AP.TM.getTargetData(); 1524 unsigned Size = TD->getTypeAllocSize(CS->getType()); 1525 const StructLayout *Layout = TD->getStructLayout(CS->getType()); 1526 uint64_t SizeSoFar = 0; 1527 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 1528 const Constant *Field = CS->getOperand(i); 1529 1530 // Check if padding is needed and insert one or more 0s. 1531 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType()); 1532 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1)) 1533 - Layout->getElementOffset(i)) - FieldSize; 1534 SizeSoFar += FieldSize + PadSize; 1535 1536 // Now print the actual field value. 1537 EmitGlobalConstantImpl(Field, AddrSpace, AP); 1538 1539 // Insert padding - this may include padding to increase the size of the 1540 // current field up to the ABI size (if the struct is not packed) as well 1541 // as padding to ensure that the next field starts at the right offset. 1542 AP.OutStreamer.EmitZeros(PadSize, AddrSpace); 1543 } 1544 assert(SizeSoFar == Layout->getSizeInBytes() && 1545 "Layout of constant struct may be incorrect!"); 1546} 1547 1548static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace, 1549 AsmPrinter &AP) { 1550 // FP Constants are printed as integer constants to avoid losing 1551 // precision. 1552 if (CFP->getType()->isDoubleTy()) { 1553 if (AP.isVerbose()) { 1554 double Val = CFP->getValueAPF().convertToDouble(); 1555 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n'; 1556 } 1557 1558 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1559 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1560 return; 1561 } 1562 1563 if (CFP->getType()->isFloatTy()) { 1564 if (AP.isVerbose()) { 1565 float Val = CFP->getValueAPF().convertToFloat(); 1566 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n'; 1567 } 1568 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1569 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace); 1570 return; 1571 } 1572 1573 if (CFP->getType()->isX86_FP80Ty()) { 1574 // all long double variants are printed as hex 1575 // API needed to prevent premature destruction 1576 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1577 const uint64_t *p = API.getRawData(); 1578 if (AP.isVerbose()) { 1579 // Convert to double so we can print the approximate val as a comment. 1580 APFloat DoubleVal = CFP->getValueAPF(); 1581 bool ignored; 1582 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 1583 &ignored); 1584 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= " 1585 << DoubleVal.convertToDouble() << '\n'; 1586 } 1587 1588 if (AP.TM.getTargetData()->isBigEndian()) { 1589 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1590 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1591 } else { 1592 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1593 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1594 } 1595 1596 // Emit the tail padding for the long double. 1597 const TargetData &TD = *AP.TM.getTargetData(); 1598 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) - 1599 TD.getTypeStoreSize(CFP->getType()), AddrSpace); 1600 return; 1601 } 1602 1603 assert(CFP->getType()->isPPC_FP128Ty() && 1604 "Floating point constant type not handled"); 1605 // All long double variants are printed as hex 1606 // API needed to prevent premature destruction. 1607 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1608 const uint64_t *p = API.getRawData(); 1609 if (AP.TM.getTargetData()->isBigEndian()) { 1610 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1611 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1612 } else { 1613 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1614 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1615 } 1616} 1617 1618static void EmitGlobalConstantLargeInt(const ConstantInt *CI, 1619 unsigned AddrSpace, AsmPrinter &AP) { 1620 const TargetData *TD = AP.TM.getTargetData(); 1621 unsigned BitWidth = CI->getBitWidth(); 1622 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits"); 1623 1624 // We don't expect assemblers to support integer data directives 1625 // for more than 64 bits, so we emit the data in at most 64-bit 1626 // quantities at a time. 1627 const uint64_t *RawData = CI->getValue().getRawData(); 1628 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) { 1629 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i]; 1630 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1631 } 1632} 1633 1634static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace, 1635 AsmPrinter &AP) { 1636 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) { 1637 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1638 return AP.OutStreamer.EmitZeros(Size, AddrSpace); 1639 } 1640 1641 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { 1642 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1643 switch (Size) { 1644 case 1: 1645 case 2: 1646 case 4: 1647 case 8: 1648 if (AP.isVerbose()) 1649 AP.OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue()); 1650 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace); 1651 return; 1652 default: 1653 EmitGlobalConstantLargeInt(CI, AddrSpace, AP); 1654 return; 1655 } 1656 } 1657 1658 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) 1659 return EmitGlobalConstantArray(CVA, AddrSpace, AP); 1660 1661 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) 1662 return EmitGlobalConstantStruct(CVS, AddrSpace, AP); 1663 1664 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) 1665 return EmitGlobalConstantFP(CFP, AddrSpace, AP); 1666 1667 if (isa<ConstantPointerNull>(CV)) { 1668 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1669 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace); 1670 return; 1671 } 1672 1673 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV)) 1674 return EmitGlobalConstantVector(V, AddrSpace, AP); 1675 1676 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it 1677 // thread the streamer with EmitValue. 1678 AP.OutStreamer.EmitValue(LowerConstant(CV, AP), 1679 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()), 1680 AddrSpace); 1681} 1682 1683/// EmitGlobalConstant - Print a general LLVM constant to the .s file. 1684void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) { 1685 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1686 if (Size) 1687 EmitGlobalConstantImpl(CV, AddrSpace, *this); 1688 else if (MAI->hasSubsectionsViaSymbols()) { 1689 // If the global has zero size, emit a single byte so that two labels don't 1690 // look like they are at the same location. 1691 OutStreamer.EmitIntValue(0, 1, AddrSpace); 1692 } 1693} 1694 1695void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 1696 // Target doesn't support this yet! 1697 llvm_unreachable("Target does not support EmitMachineConstantPoolValue"); 1698} 1699 1700void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const { 1701 if (Offset > 0) 1702 OS << '+' << Offset; 1703 else if (Offset < 0) 1704 OS << Offset; 1705} 1706 1707//===----------------------------------------------------------------------===// 1708// Symbol Lowering Routines. 1709//===----------------------------------------------------------------------===// 1710 1711/// GetTempSymbol - Return the MCSymbol corresponding to the assembler 1712/// temporary label with the specified stem and unique ID. 1713MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const { 1714 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + 1715 Name + Twine(ID)); 1716} 1717 1718/// GetTempSymbol - Return an assembler temporary label with the specified 1719/// stem. 1720MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const { 1721 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+ 1722 Name); 1723} 1724 1725 1726MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const { 1727 return MMI->getAddrLabelSymbol(BA->getBasicBlock()); 1728} 1729 1730MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const { 1731 return MMI->getAddrLabelSymbol(BB); 1732} 1733 1734/// GetCPISymbol - Return the symbol for the specified constant pool entry. 1735MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const { 1736 return OutContext.GetOrCreateSymbol 1737 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber()) 1738 + "_" + Twine(CPID)); 1739} 1740 1741/// GetJTISymbol - Return the symbol for the specified jump table entry. 1742MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const { 1743 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate); 1744} 1745 1746/// GetJTSetSymbol - Return the symbol for the specified jump table .set 1747/// FIXME: privatize to AsmPrinter. 1748MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const { 1749 return OutContext.GetOrCreateSymbol 1750 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" + 1751 Twine(UID) + "_set_" + Twine(MBBID)); 1752} 1753 1754/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with 1755/// global value name as its base, with the specified suffix, and where the 1756/// symbol is forced to have private linkage if ForcePrivate is true. 1757MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV, 1758 StringRef Suffix, 1759 bool ForcePrivate) const { 1760 SmallString<60> NameStr; 1761 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate); 1762 NameStr.append(Suffix.begin(), Suffix.end()); 1763 return OutContext.GetOrCreateSymbol(NameStr.str()); 1764} 1765 1766/// GetExternalSymbolSymbol - Return the MCSymbol for the specified 1767/// ExternalSymbol. 1768MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const { 1769 SmallString<60> NameStr; 1770 Mang->getNameWithPrefix(NameStr, Sym); 1771 return OutContext.GetOrCreateSymbol(NameStr.str()); 1772} 1773 1774 1775 1776/// PrintParentLoopComment - Print comments about parent loops of this one. 1777static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1778 unsigned FunctionNumber) { 1779 if (Loop == 0) return; 1780 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber); 1781 OS.indent(Loop->getLoopDepth()*2) 1782 << "Parent Loop BB" << FunctionNumber << "_" 1783 << Loop->getHeader()->getNumber() 1784 << " Depth=" << Loop->getLoopDepth() << '\n'; 1785} 1786 1787 1788/// PrintChildLoopComment - Print comments about child loops within 1789/// the loop for this basic block, with nesting. 1790static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1791 unsigned FunctionNumber) { 1792 // Add child loop information 1793 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){ 1794 OS.indent((*CL)->getLoopDepth()*2) 1795 << "Child Loop BB" << FunctionNumber << "_" 1796 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth() 1797 << '\n'; 1798 PrintChildLoopComment(OS, *CL, FunctionNumber); 1799 } 1800} 1801 1802/// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks. 1803static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB, 1804 const MachineLoopInfo *LI, 1805 const AsmPrinter &AP) { 1806 // Add loop depth information 1807 const MachineLoop *Loop = LI->getLoopFor(&MBB); 1808 if (Loop == 0) return; 1809 1810 MachineBasicBlock *Header = Loop->getHeader(); 1811 assert(Header && "No header for loop"); 1812 1813 // If this block is not a loop header, just print out what is the loop header 1814 // and return. 1815 if (Header != &MBB) { 1816 AP.OutStreamer.AddComment(" in Loop: Header=BB" + 1817 Twine(AP.getFunctionNumber())+"_" + 1818 Twine(Loop->getHeader()->getNumber())+ 1819 " Depth="+Twine(Loop->getLoopDepth())); 1820 return; 1821 } 1822 1823 // Otherwise, it is a loop header. Print out information about child and 1824 // parent loops. 1825 raw_ostream &OS = AP.OutStreamer.GetCommentOS(); 1826 1827 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 1828 1829 OS << "=>"; 1830 OS.indent(Loop->getLoopDepth()*2-2); 1831 1832 OS << "This "; 1833 if (Loop->empty()) 1834 OS << "Inner "; 1835 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n'; 1836 1837 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber()); 1838} 1839 1840 1841/// EmitBasicBlockStart - This method prints the label for the specified 1842/// MachineBasicBlock, an alignment (if present) and a comment describing 1843/// it if appropriate. 1844void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const { 1845 // Emit an alignment directive for this block, if needed. 1846 if (unsigned Align = MBB->getAlignment()) 1847 EmitAlignment(Log2_32(Align)); 1848 1849 // If the block has its address taken, emit any labels that were used to 1850 // reference the block. It is possible that there is more than one label 1851 // here, because multiple LLVM BB's may have been RAUW'd to this block after 1852 // the references were generated. 1853 if (MBB->hasAddressTaken()) { 1854 const BasicBlock *BB = MBB->getBasicBlock(); 1855 if (isVerbose()) 1856 OutStreamer.AddComment("Block address taken"); 1857 1858 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB); 1859 1860 for (unsigned i = 0, e = Syms.size(); i != e; ++i) 1861 OutStreamer.EmitLabel(Syms[i]); 1862 } 1863 1864 // Print the main label for the block. 1865 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) { 1866 if (isVerbose() && OutStreamer.hasRawTextSupport()) { 1867 if (const BasicBlock *BB = MBB->getBasicBlock()) 1868 if (BB->hasName()) 1869 OutStreamer.AddComment("%" + BB->getName()); 1870 1871 EmitBasicBlockLoopComments(*MBB, LI, *this); 1872 1873 // NOTE: Want this comment at start of line, don't emit with AddComment. 1874 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" + 1875 Twine(MBB->getNumber()) + ":"); 1876 } 1877 } else { 1878 if (isVerbose()) { 1879 if (const BasicBlock *BB = MBB->getBasicBlock()) 1880 if (BB->hasName()) 1881 OutStreamer.AddComment("%" + BB->getName()); 1882 EmitBasicBlockLoopComments(*MBB, LI, *this); 1883 } 1884 1885 OutStreamer.EmitLabel(MBB->getSymbol()); 1886 } 1887} 1888 1889void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility, 1890 bool IsDefinition) const { 1891 MCSymbolAttr Attr = MCSA_Invalid; 1892 1893 switch (Visibility) { 1894 default: break; 1895 case GlobalValue::HiddenVisibility: 1896 if (IsDefinition) 1897 Attr = MAI->getHiddenVisibilityAttr(); 1898 else 1899 Attr = MAI->getHiddenDeclarationVisibilityAttr(); 1900 break; 1901 case GlobalValue::ProtectedVisibility: 1902 Attr = MAI->getProtectedVisibilityAttr(); 1903 break; 1904 } 1905 1906 if (Attr != MCSA_Invalid) 1907 OutStreamer.EmitSymbolAttribute(Sym, Attr); 1908} 1909 1910/// isBlockOnlyReachableByFallthough - Return true if the basic block has 1911/// exactly one predecessor and the control transfer mechanism between 1912/// the predecessor and this block is a fall-through. 1913bool AsmPrinter:: 1914isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const { 1915 // If this is a landing pad, it isn't a fall through. If it has no preds, 1916 // then nothing falls through to it. 1917 if (MBB->isLandingPad() || MBB->pred_empty()) 1918 return false; 1919 1920 // If there isn't exactly one predecessor, it can't be a fall through. 1921 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI; 1922 ++PI2; 1923 if (PI2 != MBB->pred_end()) 1924 return false; 1925 1926 // The predecessor has to be immediately before this block. 1927 const MachineBasicBlock *Pred = *PI; 1928 1929 if (!Pred->isLayoutSuccessor(MBB)) 1930 return false; 1931 1932 // If the block is completely empty, then it definitely does fall through. 1933 if (Pred->empty()) 1934 return true; 1935 1936 // Otherwise, check the last instruction. 1937 const MachineInstr &LastInst = Pred->back(); 1938 return !LastInst.getDesc().isBarrier(); 1939} 1940 1941 1942 1943GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) { 1944 if (!S->usesMetadata()) 1945 return 0; 1946 1947 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 1948 gcp_map_type::iterator GCPI = GCMap.find(S); 1949 if (GCPI != GCMap.end()) 1950 return GCPI->second; 1951 1952 const char *Name = S->getName().c_str(); 1953 1954 for (GCMetadataPrinterRegistry::iterator 1955 I = GCMetadataPrinterRegistry::begin(), 1956 E = GCMetadataPrinterRegistry::end(); I != E; ++I) 1957 if (strcmp(Name, I->getName()) == 0) { 1958 GCMetadataPrinter *GMP = I->instantiate(); 1959 GMP->S = S; 1960 GCMap.insert(std::make_pair(S, GMP)); 1961 return GMP; 1962 } 1963 1964 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name)); 1965 return 0; 1966} 1967 1968