AsmPrinter.cpp revision b464d3ff72790260e8c2068afe856fd7299a6834
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/TargetData.h" 37#include "llvm/Target/TargetInstrInfo.h" 38#include "llvm/Target/TargetLowering.h" 39#include "llvm/Target/TargetLoweringObjectFile.h" 40#include "llvm/Target/TargetOptions.h" 41#include "llvm/Target/TargetRegisterInfo.h" 42#include "llvm/Assembly/Writer.h" 43#include "llvm/ADT/SmallString.h" 44#include "llvm/ADT/Statistic.h" 45#include "llvm/Support/ErrorHandling.h" 46#include "llvm/Support/Format.h" 47#include "llvm/Support/MathExtras.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 case ExceptionHandling::DwarfCFI: 197 DE = new DwarfCFIException(this); 198 return false; 199 case ExceptionHandling::ARM: 200 DE = new ARMException(this); 201 return false; 202 case ExceptionHandling::Win64: 203 DE = new Win64Exception(this); 204 return false; 205 } 206 207 llvm_unreachable("Unknown exception type."); 208} 209 210void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const { 211 switch ((GlobalValue::LinkageTypes)Linkage) { 212 case GlobalValue::CommonLinkage: 213 case GlobalValue::LinkOnceAnyLinkage: 214 case GlobalValue::LinkOnceODRLinkage: 215 case GlobalValue::WeakAnyLinkage: 216 case GlobalValue::WeakODRLinkage: 217 case GlobalValue::LinkerPrivateWeakLinkage: 218 case GlobalValue::LinkerPrivateWeakDefAutoLinkage: 219 if (MAI->getWeakDefDirective() != 0) { 220 // .globl _foo 221 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 222 223 if ((GlobalValue::LinkageTypes)Linkage != 224 GlobalValue::LinkerPrivateWeakDefAutoLinkage) 225 // .weak_definition _foo 226 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition); 227 else 228 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate); 229 } else if (MAI->getLinkOnceDirective() != 0) { 230 // .globl _foo 231 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 232 //NOTE: linkonce is handled by the section the symbol was assigned to. 233 } else { 234 // .weak _foo 235 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak); 236 } 237 break; 238 case GlobalValue::DLLExportLinkage: 239 case GlobalValue::AppendingLinkage: 240 // FIXME: appending linkage variables should go into a section of 241 // their name or something. For now, just emit them as external. 242 case GlobalValue::ExternalLinkage: 243 // If external or appending, declare as a global symbol. 244 // .globl _foo 245 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 246 break; 247 case GlobalValue::PrivateLinkage: 248 case GlobalValue::InternalLinkage: 249 case GlobalValue::LinkerPrivateLinkage: 250 break; 251 default: 252 llvm_unreachable("Unknown linkage type!"); 253 } 254} 255 256 257/// EmitGlobalVariable - Emit the specified global variable to the .s file. 258void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) { 259 if (GV->hasInitializer()) { 260 // Check to see if this is a special global used by LLVM, if so, emit it. 261 if (EmitSpecialLLVMGlobal(GV)) 262 return; 263 264 if (isVerbose()) { 265 WriteAsOperand(OutStreamer.GetCommentOS(), GV, 266 /*PrintType=*/false, GV->getParent()); 267 OutStreamer.GetCommentOS() << '\n'; 268 } 269 } 270 271 MCSymbol *GVSym = Mang->getSymbol(GV); 272 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration()); 273 274 if (!GV->hasInitializer()) // External globals require no extra code. 275 return; 276 277 if (MAI->hasDotTypeDotSizeDirective()) 278 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject); 279 280 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM); 281 282 const TargetData *TD = TM.getTargetData(); 283 uint64_t Size = TD->getTypeAllocSize(GV->getType()->getElementType()); 284 285 // If the alignment is specified, we *must* obey it. Overaligning a global 286 // with a specified alignment is a prompt way to break globals emitted to 287 // sections and expected to be contiguous (e.g. ObjC metadata). 288 unsigned AlignLog = getGVAlignmentLog2(GV, *TD); 289 290 // Handle common and BSS local symbols (.lcomm). 291 if (GVKind.isCommon() || GVKind.isBSSLocal()) { 292 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. 293 unsigned Align = 1 << AlignLog; 294 295 // Handle common symbols. 296 if (GVKind.isCommon()) { 297 if (!getObjFileLowering().getCommDirectiveSupportsAlignment()) 298 Align = 0; 299 300 // .comm _foo, 42, 4 301 OutStreamer.EmitCommonSymbol(GVSym, Size, Align); 302 return; 303 } 304 305 // Handle local BSS symbols. 306 if (MAI->hasMachoZeroFillDirective()) { 307 const MCSection *TheSection = 308 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 309 // .zerofill __DATA, __bss, _foo, 400, 5 310 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align); 311 return; 312 } 313 314 if (MAI->getLCOMMDirectiveType() != LCOMM::None && 315 (MAI->getLCOMMDirectiveType() != LCOMM::NoAlignment || Align == 1)) { 316 // .lcomm _foo, 42 317 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align); 318 return; 319 } 320 321 if (!getObjFileLowering().getCommDirectiveSupportsAlignment()) 322 Align = 0; 323 324 // .local _foo 325 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local); 326 // .comm _foo, 42, 4 327 OutStreamer.EmitCommonSymbol(GVSym, Size, Align); 328 return; 329 } 330 331 const MCSection *TheSection = 332 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 333 334 // Handle the zerofill directive on darwin, which is a special form of BSS 335 // emission. 336 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) { 337 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined. 338 339 // .globl _foo 340 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 341 // .zerofill __DATA, __common, _foo, 400, 5 342 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog); 343 return; 344 } 345 346 // Handle thread local data for mach-o which requires us to output an 347 // additional structure of data and mangle the original symbol so that we 348 // can reference it later. 349 // 350 // TODO: This should become an "emit thread local global" method on TLOF. 351 // All of this macho specific stuff should be sunk down into TLOFMachO and 352 // stuff like "TLSExtraDataSection" should no longer be part of the parent 353 // TLOF class. This will also make it more obvious that stuff like 354 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho 355 // specific code. 356 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) { 357 // Emit the .tbss symbol 358 MCSymbol *MangSym = 359 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init")); 360 361 if (GVKind.isThreadBSS()) 362 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog); 363 else if (GVKind.isThreadData()) { 364 OutStreamer.SwitchSection(TheSection); 365 366 EmitAlignment(AlignLog, GV); 367 OutStreamer.EmitLabel(MangSym); 368 369 EmitGlobalConstant(GV->getInitializer()); 370 } 371 372 OutStreamer.AddBlankLine(); 373 374 // Emit the variable struct for the runtime. 375 const MCSection *TLVSect 376 = getObjFileLowering().getTLSExtraDataSection(); 377 378 OutStreamer.SwitchSection(TLVSect); 379 // Emit the linkage here. 380 EmitLinkage(GV->getLinkage(), GVSym); 381 OutStreamer.EmitLabel(GVSym); 382 383 // Three pointers in size: 384 // - __tlv_bootstrap - used to make sure support exists 385 // - spare pointer, used when mapped by the runtime 386 // - pointer to mangled symbol above with initializer 387 unsigned PtrSize = TD->getPointerSizeInBits()/8; 388 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"), 389 PtrSize, 0); 390 OutStreamer.EmitIntValue(0, PtrSize, 0); 391 OutStreamer.EmitSymbolValue(MangSym, PtrSize, 0); 392 393 OutStreamer.AddBlankLine(); 394 return; 395 } 396 397 OutStreamer.SwitchSection(TheSection); 398 399 EmitLinkage(GV->getLinkage(), GVSym); 400 EmitAlignment(AlignLog, GV); 401 402 OutStreamer.EmitLabel(GVSym); 403 404 EmitGlobalConstant(GV->getInitializer()); 405 406 if (MAI->hasDotTypeDotSizeDirective()) 407 // .size foo, 42 408 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext)); 409 410 OutStreamer.AddBlankLine(); 411} 412 413/// EmitFunctionHeader - This method emits the header for the current 414/// function. 415void AsmPrinter::EmitFunctionHeader() { 416 // Print out constants referenced by the function 417 EmitConstantPool(); 418 419 // Print the 'header' of function. 420 const Function *F = MF->getFunction(); 421 422 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM)); 423 EmitVisibility(CurrentFnSym, F->getVisibility()); 424 425 EmitLinkage(F->getLinkage(), CurrentFnSym); 426 EmitAlignment(MF->getAlignment(), F); 427 428 if (MAI->hasDotTypeDotSizeDirective()) 429 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction); 430 431 if (isVerbose()) { 432 WriteAsOperand(OutStreamer.GetCommentOS(), F, 433 /*PrintType=*/false, F->getParent()); 434 OutStreamer.GetCommentOS() << '\n'; 435 } 436 437 // Emit the CurrentFnSym. This is a virtual function to allow targets to 438 // do their wild and crazy things as required. 439 EmitFunctionEntryLabel(); 440 441 // If the function had address-taken blocks that got deleted, then we have 442 // references to the dangling symbols. Emit them at the start of the function 443 // so that we don't get references to undefined symbols. 444 std::vector<MCSymbol*> DeadBlockSyms; 445 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms); 446 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) { 447 OutStreamer.AddComment("Address taken block that was later removed"); 448 OutStreamer.EmitLabel(DeadBlockSyms[i]); 449 } 450 451 // Add some workaround for linkonce linkage on Cygwin\MinGW. 452 if (MAI->getLinkOnceDirective() != 0 && 453 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) { 454 // FIXME: What is this? 455 MCSymbol *FakeStub = 456 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+ 457 CurrentFnSym->getName()); 458 OutStreamer.EmitLabel(FakeStub); 459 } 460 461 // Emit pre-function debug and/or EH information. 462 if (DE) { 463 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 464 DE->BeginFunction(MF); 465 } 466 if (DD) { 467 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 468 DD->beginFunction(MF); 469 } 470} 471 472/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the 473/// function. This can be overridden by targets as required to do custom stuff. 474void AsmPrinter::EmitFunctionEntryLabel() { 475 // The function label could have already been emitted if two symbols end up 476 // conflicting due to asm renaming. Detect this and emit an error. 477 if (CurrentFnSym->isUndefined()) { 478 OutStreamer.ForceCodeRegion(); 479 return OutStreamer.EmitLabel(CurrentFnSym); 480 } 481 482 report_fatal_error("'" + Twine(CurrentFnSym->getName()) + 483 "' label emitted multiple times to assembly file"); 484} 485 486 487/// EmitComments - Pretty-print comments for instructions. 488static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) { 489 const MachineFunction *MF = MI.getParent()->getParent(); 490 const TargetMachine &TM = MF->getTarget(); 491 492 // Check for spills and reloads 493 int FI; 494 495 const MachineFrameInfo *FrameInfo = MF->getFrameInfo(); 496 497 // We assume a single instruction only has a spill or reload, not 498 // both. 499 const MachineMemOperand *MMO; 500 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) { 501 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 502 MMO = *MI.memoperands_begin(); 503 CommentOS << MMO->getSize() << "-byte Reload\n"; 504 } 505 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) { 506 if (FrameInfo->isSpillSlotObjectIndex(FI)) 507 CommentOS << MMO->getSize() << "-byte Folded Reload\n"; 508 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) { 509 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 510 MMO = *MI.memoperands_begin(); 511 CommentOS << MMO->getSize() << "-byte Spill\n"; 512 } 513 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) { 514 if (FrameInfo->isSpillSlotObjectIndex(FI)) 515 CommentOS << MMO->getSize() << "-byte Folded Spill\n"; 516 } 517 518 // Check for spill-induced copies 519 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse)) 520 CommentOS << " Reload Reuse\n"; 521} 522 523/// EmitImplicitDef - This method emits the specified machine instruction 524/// that is an implicit def. 525static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) { 526 unsigned RegNo = MI->getOperand(0).getReg(); 527 AP.OutStreamer.AddComment(Twine("implicit-def: ") + 528 AP.TM.getRegisterInfo()->getName(RegNo)); 529 AP.OutStreamer.AddBlankLine(); 530} 531 532static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) { 533 std::string Str = "kill:"; 534 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 535 const MachineOperand &Op = MI->getOperand(i); 536 assert(Op.isReg() && "KILL instruction must have only register operands"); 537 Str += ' '; 538 Str += AP.TM.getRegisterInfo()->getName(Op.getReg()); 539 Str += (Op.isDef() ? "<def>" : "<kill>"); 540 } 541 AP.OutStreamer.AddComment(Str); 542 AP.OutStreamer.AddBlankLine(); 543} 544 545/// EmitDebugValueComment - This method handles the target-independent form 546/// of DBG_VALUE, returning true if it was able to do so. A false return 547/// means the target will need to handle MI in EmitInstruction. 548static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) { 549 // This code handles only the 3-operand target-independent form. 550 if (MI->getNumOperands() != 3) 551 return false; 552 553 SmallString<128> Str; 554 raw_svector_ostream OS(Str); 555 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: "; 556 557 // cast away const; DIetc do not take const operands for some reason. 558 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata())); 559 if (V.getContext().isSubprogram()) 560 OS << DISubprogram(V.getContext()).getDisplayName() << ":"; 561 OS << V.getName() << " <- "; 562 563 // Register or immediate value. Register 0 means undef. 564 if (MI->getOperand(0).isFPImm()) { 565 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF()); 566 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) { 567 OS << (double)APF.convertToFloat(); 568 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) { 569 OS << APF.convertToDouble(); 570 } else { 571 // There is no good way to print long double. Convert a copy to 572 // double. Ah well, it's only a comment. 573 bool ignored; 574 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 575 &ignored); 576 OS << "(long double) " << APF.convertToDouble(); 577 } 578 } else if (MI->getOperand(0).isImm()) { 579 OS << MI->getOperand(0).getImm(); 580 } else if (MI->getOperand(0).isCImm()) { 581 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/); 582 } else { 583 assert(MI->getOperand(0).isReg() && "Unknown operand type"); 584 if (MI->getOperand(0).getReg() == 0) { 585 // Suppress offset, it is not meaningful here. 586 OS << "undef"; 587 // NOTE: Want this comment at start of line, don't emit with AddComment. 588 AP.OutStreamer.EmitRawText(OS.str()); 589 return true; 590 } 591 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg()); 592 } 593 594 OS << '+' << MI->getOperand(1).getImm(); 595 // NOTE: Want this comment at start of line, don't emit with AddComment. 596 AP.OutStreamer.EmitRawText(OS.str()); 597 return true; 598} 599 600AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() { 601 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI && 602 MF->getFunction()->needsUnwindTableEntry()) 603 return CFI_M_EH; 604 605 if (MMI->hasDebugInfo()) 606 return CFI_M_Debug; 607 608 return CFI_M_None; 609} 610 611bool AsmPrinter::needsSEHMoves() { 612 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 && 613 MF->getFunction()->needsUnwindTableEntry(); 614} 615 616bool AsmPrinter::needsRelocationsForDwarfStringPool() const { 617 return MAI->doesDwarfUseRelocationsForStringPool(); 618} 619 620void AsmPrinter::emitPrologLabel(const MachineInstr &MI) { 621 MCSymbol *Label = MI.getOperand(0).getMCSymbol(); 622 623 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI) 624 return; 625 626 if (needsCFIMoves() == CFI_M_None) 627 return; 628 629 if (MMI->getCompactUnwindEncoding() != 0) 630 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding()); 631 632 MachineModuleInfo &MMI = MF->getMMI(); 633 std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 634 bool FoundOne = false; 635 (void)FoundOne; 636 for (std::vector<MachineMove>::iterator I = Moves.begin(), 637 E = Moves.end(); I != E; ++I) { 638 if (I->getLabel() == Label) { 639 EmitCFIFrameMove(*I); 640 FoundOne = true; 641 } 642 } 643 assert(FoundOne); 644} 645 646/// EmitFunctionBody - This method emits the body and trailer for a 647/// function. 648void AsmPrinter::EmitFunctionBody() { 649 // Emit target-specific gunk before the function body. 650 EmitFunctionBodyStart(); 651 652 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo(); 653 654 // Print out code for the function. 655 bool HasAnyRealCode = false; 656 const MachineInstr *LastMI = 0; 657 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 658 I != E; ++I) { 659 // Print a label for the basic block. 660 EmitBasicBlockStart(I); 661 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 662 II != IE; ++II) { 663 LastMI = II; 664 665 // Print the assembly for the instruction. 666 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() && 667 !II->isDebugValue()) { 668 HasAnyRealCode = true; 669 ++EmittedInsts; 670 } 671 672 if (ShouldPrintDebugScopes) { 673 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 674 DD->beginInstruction(II); 675 } 676 677 if (isVerbose()) 678 EmitComments(*II, OutStreamer.GetCommentOS()); 679 680 switch (II->getOpcode()) { 681 case TargetOpcode::PROLOG_LABEL: 682 emitPrologLabel(*II); 683 break; 684 685 case TargetOpcode::EH_LABEL: 686 case TargetOpcode::GC_LABEL: 687 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol()); 688 break; 689 case TargetOpcode::INLINEASM: 690 EmitInlineAsm(II); 691 break; 692 case TargetOpcode::DBG_VALUE: 693 if (isVerbose()) { 694 if (!EmitDebugValueComment(II, *this)) 695 EmitInstruction(II); 696 } 697 break; 698 case TargetOpcode::IMPLICIT_DEF: 699 if (isVerbose()) EmitImplicitDef(II, *this); 700 break; 701 case TargetOpcode::KILL: 702 if (isVerbose()) EmitKill(II, *this); 703 break; 704 default: 705 if (!TM.hasMCUseLoc()) 706 MCLineEntry::Make(&OutStreamer, getCurrentSection()); 707 708 EmitInstruction(II); 709 break; 710 } 711 712 if (ShouldPrintDebugScopes) { 713 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 714 DD->endInstruction(II); 715 } 716 } 717 } 718 719 // If the last instruction was a prolog label, then we have a situation where 720 // we emitted a prolog but no function body. This results in the ending prolog 721 // label equaling the end of function label and an invalid "row" in the 722 // FDE. We need to emit a noop in this situation so that the FDE's rows are 723 // valid. 724 bool RequiresNoop = LastMI && LastMI->isPrologLabel(); 725 726 // If the function is empty and the object file uses .subsections_via_symbols, 727 // then we need to emit *something* to the function body to prevent the 728 // labels from collapsing together. Just emit a noop. 729 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) { 730 MCInst Noop; 731 TM.getInstrInfo()->getNoopForMachoTarget(Noop); 732 if (Noop.getOpcode()) { 733 OutStreamer.AddComment("avoids zero-length function"); 734 OutStreamer.EmitInstruction(Noop); 735 } else // Target not mc-ized yet. 736 OutStreamer.EmitRawText(StringRef("\tnop\n")); 737 } 738 739 const Function *F = MF->getFunction(); 740 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) { 741 const BasicBlock *BB = i; 742 if (!BB->hasAddressTaken()) 743 continue; 744 MCSymbol *Sym = GetBlockAddressSymbol(BB); 745 if (Sym->isDefined()) 746 continue; 747 OutStreamer.AddComment("Address of block that was removed by CodeGen"); 748 OutStreamer.EmitLabel(Sym); 749 } 750 751 // Emit target-specific gunk after the function body. 752 EmitFunctionBodyEnd(); 753 754 // If the target wants a .size directive for the size of the function, emit 755 // it. 756 if (MAI->hasDotTypeDotSizeDirective()) { 757 // Create a symbol for the end of function, so we can get the size as 758 // difference between the function label and the temp label. 759 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol(); 760 OutStreamer.EmitLabel(FnEndLabel); 761 762 const MCExpr *SizeExp = 763 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext), 764 MCSymbolRefExpr::Create(CurrentFnSym, OutContext), 765 OutContext); 766 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp); 767 } 768 769 // Emit post-function debug information. 770 if (DD) { 771 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 772 DD->endFunction(MF); 773 } 774 if (DE) { 775 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 776 DE->EndFunction(); 777 } 778 MMI->EndFunction(); 779 780 // Print out jump tables referenced by the function. 781 EmitJumpTableInfo(); 782 783 OutStreamer.AddBlankLine(); 784} 785 786/// getDebugValueLocation - Get location information encoded by DBG_VALUE 787/// operands. 788MachineLocation AsmPrinter:: 789getDebugValueLocation(const MachineInstr *MI) const { 790 // Target specific DBG_VALUE instructions are handled by each target. 791 return MachineLocation(); 792} 793 794/// EmitDwarfRegOp - Emit dwarf register operation. 795void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const { 796 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 797 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false); 798 799 for (const unsigned *SR = TRI->getSuperRegisters(MLoc.getReg()); 800 *SR && Reg < 0; ++SR) { 801 Reg = TRI->getDwarfRegNum(*SR, false); 802 // FIXME: Get the bit range this register uses of the superregister 803 // so that we can produce a DW_OP_bit_piece 804 } 805 806 // FIXME: Handle cases like a super register being encoded as 807 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33 808 809 // FIXME: We have no reasonable way of handling errors in here. The 810 // caller might be in the middle of an dwarf expression. We should 811 // probably assert that Reg >= 0 once debug info generation is more mature. 812 813 if (int Offset = MLoc.getOffset()) { 814 if (Reg < 32) { 815 OutStreamer.AddComment( 816 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg)); 817 EmitInt8(dwarf::DW_OP_breg0 + Reg); 818 } else { 819 OutStreamer.AddComment("DW_OP_bregx"); 820 EmitInt8(dwarf::DW_OP_bregx); 821 OutStreamer.AddComment(Twine(Reg)); 822 EmitULEB128(Reg); 823 } 824 EmitSLEB128(Offset); 825 } else { 826 if (Reg < 32) { 827 OutStreamer.AddComment( 828 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg)); 829 EmitInt8(dwarf::DW_OP_reg0 + Reg); 830 } else { 831 OutStreamer.AddComment("DW_OP_regx"); 832 EmitInt8(dwarf::DW_OP_regx); 833 OutStreamer.AddComment(Twine(Reg)); 834 EmitULEB128(Reg); 835 } 836 } 837 838 // FIXME: Produce a DW_OP_bit_piece if we used a superregister 839} 840 841bool AsmPrinter::doFinalization(Module &M) { 842 // Emit global variables. 843 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 844 I != E; ++I) 845 EmitGlobalVariable(I); 846 847 // Emit visibility info for declarations 848 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 849 const Function &F = *I; 850 if (!F.isDeclaration()) 851 continue; 852 GlobalValue::VisibilityTypes V = F.getVisibility(); 853 if (V == GlobalValue::DefaultVisibility) 854 continue; 855 856 MCSymbol *Name = Mang->getSymbol(&F); 857 EmitVisibility(Name, V, false); 858 } 859 860 // Emit module flags. 861 if (NamedMDNode *ModFlags = M.getModuleFlagsMetadata()) 862 getObjFileLowering().emitModuleFlags(OutStreamer, ModFlags, Mang, TM); 863 864 // Finalize debug and EH information. 865 if (DE) { 866 { 867 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 868 DE->EndModule(); 869 } 870 delete DE; DE = 0; 871 } 872 if (DD) { 873 { 874 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 875 DD->endModule(); 876 } 877 delete DD; DD = 0; 878 } 879 880 // If the target wants to know about weak references, print them all. 881 if (MAI->getWeakRefDirective()) { 882 // FIXME: This is not lazy, it would be nice to only print weak references 883 // to stuff that is actually used. Note that doing so would require targets 884 // to notice uses in operands (due to constant exprs etc). This should 885 // happen with the MC stuff eventually. 886 887 // Print out module-level global variables here. 888 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 889 I != E; ++I) { 890 if (!I->hasExternalWeakLinkage()) continue; 891 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 892 } 893 894 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 895 if (!I->hasExternalWeakLinkage()) continue; 896 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 897 } 898 } 899 900 if (MAI->hasSetDirective()) { 901 OutStreamer.AddBlankLine(); 902 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end(); 903 I != E; ++I) { 904 MCSymbol *Name = Mang->getSymbol(I); 905 906 const GlobalValue *GV = I->getAliasedGlobal(); 907 MCSymbol *Target = Mang->getSymbol(GV); 908 909 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective()) 910 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global); 911 else if (I->hasWeakLinkage()) 912 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference); 913 else 914 assert(I->hasLocalLinkage() && "Invalid alias linkage"); 915 916 EmitVisibility(Name, I->getVisibility()); 917 918 // Emit the directives as assignments aka .set: 919 OutStreamer.EmitAssignment(Name, 920 MCSymbolRefExpr::Create(Target, OutContext)); 921 } 922 } 923 924 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 925 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 926 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; ) 927 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I)) 928 MP->finishAssembly(*this); 929 930 // If we don't have any trampolines, then we don't require stack memory 931 // to be executable. Some targets have a directive to declare this. 932 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline"); 933 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty()) 934 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext)) 935 OutStreamer.SwitchSection(S); 936 937 // Allow the target to emit any magic that it wants at the end of the file, 938 // after everything else has gone out. 939 EmitEndOfAsmFile(M); 940 941 delete Mang; Mang = 0; 942 MMI = 0; 943 944 OutStreamer.Finish(); 945 return false; 946} 947 948void AsmPrinter::SetupMachineFunction(MachineFunction &MF) { 949 this->MF = &MF; 950 // Get the function symbol. 951 CurrentFnSym = Mang->getSymbol(MF.getFunction()); 952 953 if (isVerbose()) 954 LI = &getAnalysis<MachineLoopInfo>(); 955} 956 957namespace { 958 // SectionCPs - Keep track the alignment, constpool entries per Section. 959 struct SectionCPs { 960 const MCSection *S; 961 unsigned Alignment; 962 SmallVector<unsigned, 4> CPEs; 963 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {} 964 }; 965} 966 967/// EmitConstantPool - Print to the current output stream assembly 968/// representations of the constants in the constant pool MCP. This is 969/// used to print out constants which have been "spilled to memory" by 970/// the code generator. 971/// 972void AsmPrinter::EmitConstantPool() { 973 const MachineConstantPool *MCP = MF->getConstantPool(); 974 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants(); 975 if (CP.empty()) return; 976 977 // Calculate sections for constant pool entries. We collect entries to go into 978 // the same section together to reduce amount of section switch statements. 979 SmallVector<SectionCPs, 4> CPSections; 980 for (unsigned i = 0, e = CP.size(); i != e; ++i) { 981 const MachineConstantPoolEntry &CPE = CP[i]; 982 unsigned Align = CPE.getAlignment(); 983 984 SectionKind Kind; 985 switch (CPE.getRelocationInfo()) { 986 default: llvm_unreachable("Unknown section kind"); 987 case 2: Kind = SectionKind::getReadOnlyWithRel(); break; 988 case 1: 989 Kind = SectionKind::getReadOnlyWithRelLocal(); 990 break; 991 case 0: 992 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) { 993 case 4: Kind = SectionKind::getMergeableConst4(); break; 994 case 8: Kind = SectionKind::getMergeableConst8(); break; 995 case 16: Kind = SectionKind::getMergeableConst16();break; 996 default: Kind = SectionKind::getMergeableConst(); break; 997 } 998 } 999 1000 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind); 1001 1002 // The number of sections are small, just do a linear search from the 1003 // last section to the first. 1004 bool Found = false; 1005 unsigned SecIdx = CPSections.size(); 1006 while (SecIdx != 0) { 1007 if (CPSections[--SecIdx].S == S) { 1008 Found = true; 1009 break; 1010 } 1011 } 1012 if (!Found) { 1013 SecIdx = CPSections.size(); 1014 CPSections.push_back(SectionCPs(S, Align)); 1015 } 1016 1017 if (Align > CPSections[SecIdx].Alignment) 1018 CPSections[SecIdx].Alignment = Align; 1019 CPSections[SecIdx].CPEs.push_back(i); 1020 } 1021 1022 // Now print stuff into the calculated sections. 1023 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) { 1024 OutStreamer.SwitchSection(CPSections[i].S); 1025 EmitAlignment(Log2_32(CPSections[i].Alignment)); 1026 1027 unsigned Offset = 0; 1028 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) { 1029 unsigned CPI = CPSections[i].CPEs[j]; 1030 MachineConstantPoolEntry CPE = CP[CPI]; 1031 1032 // Emit inter-object padding for alignment. 1033 unsigned AlignMask = CPE.getAlignment() - 1; 1034 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask; 1035 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/); 1036 1037 Type *Ty = CPE.getType(); 1038 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty); 1039 OutStreamer.EmitLabel(GetCPISymbol(CPI)); 1040 1041 if (CPE.isMachineConstantPoolEntry()) 1042 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal); 1043 else 1044 EmitGlobalConstant(CPE.Val.ConstVal); 1045 } 1046 } 1047} 1048 1049/// EmitJumpTableInfo - Print assembly representations of the jump tables used 1050/// by the current function to the current output stream. 1051/// 1052void AsmPrinter::EmitJumpTableInfo() { 1053 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 1054 if (MJTI == 0) return; 1055 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return; 1056 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 1057 if (JT.empty()) return; 1058 1059 // Pick the directive to use to print the jump table entries, and switch to 1060 // the appropriate section. 1061 const Function *F = MF->getFunction(); 1062 bool JTInDiffSection = false; 1063 if (// In PIC mode, we need to emit the jump table to the same section as the 1064 // function body itself, otherwise the label differences won't make sense. 1065 // FIXME: Need a better predicate for this: what about custom entries? 1066 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 || 1067 // We should also do if the section name is NULL or function is declared 1068 // in discardable section 1069 // FIXME: this isn't the right predicate, should be based on the MCSection 1070 // for the function. 1071 F->isWeakForLinker()) { 1072 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM)); 1073 } else { 1074 // Otherwise, drop it in the readonly section. 1075 const MCSection *ReadOnlySection = 1076 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly()); 1077 OutStreamer.SwitchSection(ReadOnlySection); 1078 JTInDiffSection = true; 1079 } 1080 1081 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData()))); 1082 1083 // If we know the form of the jump table, go ahead and tag it as such. 1084 if (!JTInDiffSection) { 1085 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32) { 1086 OutStreamer.EmitJumpTable32Region(); 1087 } else { 1088 OutStreamer.EmitDataRegion(); 1089 } 1090 } 1091 1092 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) { 1093 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 1094 1095 // If this jump table was deleted, ignore it. 1096 if (JTBBs.empty()) continue; 1097 1098 // For the EK_LabelDifference32 entry, if the target supports .set, emit a 1099 // .set directive for each unique entry. This reduces the number of 1100 // relocations the assembler will generate for the jump table. 1101 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 && 1102 MAI->hasSetDirective()) { 1103 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets; 1104 const TargetLowering *TLI = TM.getTargetLowering(); 1105 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext); 1106 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) { 1107 const MachineBasicBlock *MBB = JTBBs[ii]; 1108 if (!EmittedSets.insert(MBB)) continue; 1109 1110 // .set LJTSet, LBB32-base 1111 const MCExpr *LHS = 1112 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1113 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()), 1114 MCBinaryExpr::CreateSub(LHS, Base, OutContext)); 1115 } 1116 } 1117 1118 // On some targets (e.g. Darwin) we want to emit two consecutive labels 1119 // before each jump table. The first label is never referenced, but tells 1120 // the assembler and linker the extents of the jump table object. The 1121 // second label is actually referenced by the code. 1122 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0]) 1123 // FIXME: This doesn't have to have any specific name, just any randomly 1124 // named and numbered 'l' label would work. Simplify GetJTISymbol. 1125 OutStreamer.EmitLabel(GetJTISymbol(JTI, true)); 1126 1127 OutStreamer.EmitLabel(GetJTISymbol(JTI)); 1128 1129 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) 1130 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI); 1131 } 1132} 1133 1134/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the 1135/// current stream. 1136void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI, 1137 const MachineBasicBlock *MBB, 1138 unsigned UID) const { 1139 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block"); 1140 const MCExpr *Value = 0; 1141 switch (MJTI->getEntryKind()) { 1142 case MachineJumpTableInfo::EK_Inline: 1143 llvm_unreachable("Cannot emit EK_Inline jump table entry"); 1144 case MachineJumpTableInfo::EK_Custom32: 1145 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID, 1146 OutContext); 1147 break; 1148 case MachineJumpTableInfo::EK_BlockAddress: 1149 // EK_BlockAddress - Each entry is a plain address of block, e.g.: 1150 // .word LBB123 1151 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1152 break; 1153 case MachineJumpTableInfo::EK_GPRel32BlockAddress: { 1154 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded 1155 // with a relocation as gp-relative, e.g.: 1156 // .gprel32 LBB123 1157 MCSymbol *MBBSym = MBB->getSymbol(); 1158 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1159 return; 1160 } 1161 1162 case MachineJumpTableInfo::EK_GPRel64BlockAddress: { 1163 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded 1164 // with a relocation as gp-relative, e.g.: 1165 // .gpdword LBB123 1166 MCSymbol *MBBSym = MBB->getSymbol(); 1167 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1168 return; 1169 } 1170 1171 case MachineJumpTableInfo::EK_LabelDifference32: { 1172 // EK_LabelDifference32 - Each entry is the address of the block minus 1173 // the address of the jump table. This is used for PIC jump tables where 1174 // gprel32 is not supported. e.g.: 1175 // .word LBB123 - LJTI1_2 1176 // If the .set directive is supported, this is emitted as: 1177 // .set L4_5_set_123, LBB123 - LJTI1_2 1178 // .word L4_5_set_123 1179 1180 // If we have emitted set directives for the jump table entries, print 1181 // them rather than the entries themselves. If we're emitting PIC, then 1182 // emit the table entries as differences between two text section labels. 1183 if (MAI->hasSetDirective()) { 1184 // If we used .set, reference the .set's symbol. 1185 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()), 1186 OutContext); 1187 break; 1188 } 1189 // Otherwise, use the difference as the jump table entry. 1190 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1191 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext); 1192 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext); 1193 break; 1194 } 1195 } 1196 1197 assert(Value && "Unknown entry kind!"); 1198 1199 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData()); 1200 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0); 1201} 1202 1203 1204/// EmitSpecialLLVMGlobal - Check to see if the specified global is a 1205/// special global used by LLVM. If so, emit it and return true, otherwise 1206/// do nothing and return false. 1207bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) { 1208 if (GV->getName() == "llvm.used") { 1209 if (MAI->hasNoDeadStrip()) // No need to emit this at all. 1210 EmitLLVMUsedList(GV->getInitializer()); 1211 return true; 1212 } 1213 1214 // Ignore debug and non-emitted data. This handles llvm.compiler.used. 1215 if (GV->getSection() == "llvm.metadata" || 1216 GV->hasAvailableExternallyLinkage()) 1217 return true; 1218 1219 if (!GV->hasAppendingLinkage()) return false; 1220 1221 assert(GV->hasInitializer() && "Not a special LLVM global!"); 1222 1223 if (GV->getName() == "llvm.global_ctors") { 1224 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true); 1225 1226 if (TM.getRelocationModel() == Reloc::Static && 1227 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1228 StringRef Sym(".constructors_used"); 1229 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1230 MCSA_Reference); 1231 } 1232 return true; 1233 } 1234 1235 if (GV->getName() == "llvm.global_dtors") { 1236 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false); 1237 1238 if (TM.getRelocationModel() == Reloc::Static && 1239 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1240 StringRef Sym(".destructors_used"); 1241 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1242 MCSA_Reference); 1243 } 1244 return true; 1245 } 1246 1247 return false; 1248} 1249 1250/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each 1251/// global in the specified llvm.used list for which emitUsedDirectiveFor 1252/// is true, as being used with this directive. 1253void AsmPrinter::EmitLLVMUsedList(const Constant *List) { 1254 // Should be an array of 'i8*'. 1255 const ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1256 if (InitList == 0) return; 1257 1258 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1259 const GlobalValue *GV = 1260 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts()); 1261 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang)) 1262 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip); 1263 } 1264} 1265 1266typedef std::pair<unsigned, Constant*> Structor; 1267 1268static bool priority_order(const Structor& lhs, const Structor& rhs) { 1269 return lhs.first < rhs.first; 1270} 1271 1272/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init 1273/// priority. 1274void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) { 1275 // Should be an array of '{ int, void ()* }' structs. The first value is the 1276 // init priority. 1277 if (!isa<ConstantArray>(List)) return; 1278 1279 // Sanity check the structors list. 1280 const ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1281 if (!InitList) return; // Not an array! 1282 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType()); 1283 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs! 1284 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) || 1285 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr). 1286 1287 // Gather the structors in a form that's convenient for sorting by priority. 1288 SmallVector<Structor, 8> Structors; 1289 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1290 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i)); 1291 if (!CS) continue; // Malformed. 1292 if (CS->getOperand(1)->isNullValue()) 1293 break; // Found a null terminator, skip the rest. 1294 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0)); 1295 if (!Priority) continue; // Malformed. 1296 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535), 1297 CS->getOperand(1))); 1298 } 1299 1300 // Emit the function pointers in the target-specific order 1301 const TargetData *TD = TM.getTargetData(); 1302 unsigned Align = Log2_32(TD->getPointerPrefAlignment()); 1303 std::stable_sort(Structors.begin(), Structors.end(), priority_order); 1304 for (unsigned i = 0, e = Structors.size(); i != e; ++i) { 1305 const MCSection *OutputSection = 1306 (isCtor ? 1307 getObjFileLowering().getStaticCtorSection(Structors[i].first) : 1308 getObjFileLowering().getStaticDtorSection(Structors[i].first)); 1309 OutStreamer.SwitchSection(OutputSection); 1310 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection()) 1311 EmitAlignment(Align); 1312 EmitXXStructor(Structors[i].second); 1313 } 1314} 1315 1316//===--------------------------------------------------------------------===// 1317// Emission and print routines 1318// 1319 1320/// EmitInt8 - Emit a byte directive and value. 1321/// 1322void AsmPrinter::EmitInt8(int Value) const { 1323 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/); 1324} 1325 1326/// EmitInt16 - Emit a short directive and value. 1327/// 1328void AsmPrinter::EmitInt16(int Value) const { 1329 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/); 1330} 1331 1332/// EmitInt32 - Emit a long directive and value. 1333/// 1334void AsmPrinter::EmitInt32(int Value) const { 1335 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/); 1336} 1337 1338/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size 1339/// in bytes of the directive is specified by Size and Hi/Lo specify the 1340/// labels. This implicitly uses .set if it is available. 1341void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, 1342 unsigned Size) const { 1343 // Get the Hi-Lo expression. 1344 const MCExpr *Diff = 1345 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext), 1346 MCSymbolRefExpr::Create(Lo, OutContext), 1347 OutContext); 1348 1349 if (!MAI->hasSetDirective()) { 1350 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/); 1351 return; 1352 } 1353 1354 // Otherwise, emit with .set (aka assignment). 1355 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1356 OutStreamer.EmitAssignment(SetLabel, Diff); 1357 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/); 1358} 1359 1360/// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo" 1361/// where the size in bytes of the directive is specified by Size and Hi/Lo 1362/// specify the labels. This implicitly uses .set if it is available. 1363void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset, 1364 const MCSymbol *Lo, unsigned Size) 1365 const { 1366 1367 // Emit Hi+Offset - Lo 1368 // Get the Hi+Offset expression. 1369 const MCExpr *Plus = 1370 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext), 1371 MCConstantExpr::Create(Offset, OutContext), 1372 OutContext); 1373 1374 // Get the Hi+Offset-Lo expression. 1375 const MCExpr *Diff = 1376 MCBinaryExpr::CreateSub(Plus, 1377 MCSymbolRefExpr::Create(Lo, OutContext), 1378 OutContext); 1379 1380 if (!MAI->hasSetDirective()) 1381 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/); 1382 else { 1383 // Otherwise, emit with .set (aka assignment). 1384 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1385 OutStreamer.EmitAssignment(SetLabel, Diff); 1386 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/); 1387 } 1388} 1389 1390/// EmitLabelPlusOffset - Emit something like ".long Label+Offset" 1391/// where the size in bytes of the directive is specified by Size and Label 1392/// specifies the label. This implicitly uses .set if it is available. 1393void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset, 1394 unsigned Size) 1395 const { 1396 1397 // Emit Label+Offset 1398 const MCExpr *Plus = 1399 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Label, OutContext), 1400 MCConstantExpr::Create(Offset, OutContext), 1401 OutContext); 1402 1403 OutStreamer.EmitValue(Plus, 4, 0/*AddrSpace*/); 1404} 1405 1406 1407//===----------------------------------------------------------------------===// 1408 1409// EmitAlignment - Emit an alignment directive to the specified power of 1410// two boundary. For example, if you pass in 3 here, you will get an 8 1411// byte alignment. If a global value is specified, and if that global has 1412// an explicit alignment requested, it will override the alignment request 1413// if required for correctness. 1414// 1415void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const { 1416 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getTargetData(), NumBits); 1417 1418 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment. 1419 1420 if (getCurrentSection()->getKind().isText()) 1421 OutStreamer.EmitCodeAlignment(1 << NumBits); 1422 else 1423 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0); 1424} 1425 1426//===----------------------------------------------------------------------===// 1427// Constant emission. 1428//===----------------------------------------------------------------------===// 1429 1430/// LowerConstant - Lower the specified LLVM Constant to an MCExpr. 1431/// 1432static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) { 1433 MCContext &Ctx = AP.OutContext; 1434 1435 if (CV->isNullValue() || isa<UndefValue>(CV)) 1436 return MCConstantExpr::Create(0, Ctx); 1437 1438 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) 1439 return MCConstantExpr::Create(CI->getZExtValue(), Ctx); 1440 1441 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 1442 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx); 1443 1444 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV)) 1445 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx); 1446 1447 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV); 1448 if (CE == 0) { 1449 llvm_unreachable("Unknown constant value to lower!"); 1450 } 1451 1452 switch (CE->getOpcode()) { 1453 default: 1454 // If the code isn't optimized, there may be outstanding folding 1455 // opportunities. Attempt to fold the expression using TargetData as a 1456 // last resort before giving up. 1457 if (Constant *C = 1458 ConstantFoldConstantExpression(CE, AP.TM.getTargetData())) 1459 if (C != CE) 1460 return LowerConstant(C, AP); 1461 1462 // Otherwise report the problem to the user. 1463 { 1464 std::string S; 1465 raw_string_ostream OS(S); 1466 OS << "Unsupported expression in static initializer: "; 1467 WriteAsOperand(OS, CE, /*PrintType=*/false, 1468 !AP.MF ? 0 : AP.MF->getFunction()->getParent()); 1469 report_fatal_error(OS.str()); 1470 } 1471 case Instruction::GetElementPtr: { 1472 const TargetData &TD = *AP.TM.getTargetData(); 1473 // Generate a symbolic expression for the byte address 1474 const Constant *PtrVal = CE->getOperand(0); 1475 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end()); 1476 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), IdxVec); 1477 1478 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP); 1479 if (Offset == 0) 1480 return Base; 1481 1482 // Truncate/sext the offset to the pointer size. 1483 if (TD.getPointerSizeInBits() != 64) { 1484 int SExtAmount = 64-TD.getPointerSizeInBits(); 1485 Offset = (Offset << SExtAmount) >> SExtAmount; 1486 } 1487 1488 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx), 1489 Ctx); 1490 } 1491 1492 case Instruction::Trunc: 1493 // We emit the value and depend on the assembler to truncate the generated 1494 // expression properly. This is important for differences between 1495 // blockaddress labels. Since the two labels are in the same function, it 1496 // is reasonable to treat their delta as a 32-bit value. 1497 // FALL THROUGH. 1498 case Instruction::BitCast: 1499 return LowerConstant(CE->getOperand(0), AP); 1500 1501 case Instruction::IntToPtr: { 1502 const TargetData &TD = *AP.TM.getTargetData(); 1503 // Handle casts to pointers by changing them into casts to the appropriate 1504 // integer type. This promotes constant folding and simplifies this code. 1505 Constant *Op = CE->getOperand(0); 1506 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()), 1507 false/*ZExt*/); 1508 return LowerConstant(Op, AP); 1509 } 1510 1511 case Instruction::PtrToInt: { 1512 const TargetData &TD = *AP.TM.getTargetData(); 1513 // Support only foldable casts to/from pointers that can be eliminated by 1514 // changing the pointer to the appropriately sized integer type. 1515 Constant *Op = CE->getOperand(0); 1516 Type *Ty = CE->getType(); 1517 1518 const MCExpr *OpExpr = LowerConstant(Op, AP); 1519 1520 // We can emit the pointer value into this slot if the slot is an 1521 // integer slot equal to the size of the pointer. 1522 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType())) 1523 return OpExpr; 1524 1525 // Otherwise the pointer is smaller than the resultant integer, mask off 1526 // the high bits so we are sure to get a proper truncation if the input is 1527 // a constant expr. 1528 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType()); 1529 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx); 1530 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx); 1531 } 1532 1533 // The MC library also has a right-shift operator, but it isn't consistently 1534 // signed or unsigned between different targets. 1535 case Instruction::Add: 1536 case Instruction::Sub: 1537 case Instruction::Mul: 1538 case Instruction::SDiv: 1539 case Instruction::SRem: 1540 case Instruction::Shl: 1541 case Instruction::And: 1542 case Instruction::Or: 1543 case Instruction::Xor: { 1544 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP); 1545 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP); 1546 switch (CE->getOpcode()) { 1547 default: llvm_unreachable("Unknown binary operator constant cast expr"); 1548 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx); 1549 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx); 1550 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx); 1551 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx); 1552 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx); 1553 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx); 1554 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx); 1555 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx); 1556 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx); 1557 } 1558 } 1559 } 1560} 1561 1562static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace, 1563 AsmPrinter &AP); 1564 1565/// isRepeatedByteSequence - Determine whether the given value is 1566/// composed of a repeated sequence of identical bytes and return the 1567/// byte value. If it is not a repeated sequence, return -1. 1568static int isRepeatedByteSequence(const ConstantDataSequential *V) { 1569 StringRef Data = V->getRawDataValues(); 1570 assert(!Data.empty() && "Empty aggregates should be CAZ node"); 1571 char C = Data[0]; 1572 for (unsigned i = 1, e = Data.size(); i != e; ++i) 1573 if (Data[i] != C) return -1; 1574 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1. 1575} 1576 1577 1578/// isRepeatedByteSequence - Determine whether the given value is 1579/// composed of a repeated sequence of identical bytes and return the 1580/// byte value. If it is not a repeated sequence, return -1. 1581static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) { 1582 1583 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { 1584 if (CI->getBitWidth() > 64) return -1; 1585 1586 uint64_t Size = TM.getTargetData()->getTypeAllocSize(V->getType()); 1587 uint64_t Value = CI->getZExtValue(); 1588 1589 // Make sure the constant is at least 8 bits long and has a power 1590 // of 2 bit width. This guarantees the constant bit width is 1591 // always a multiple of 8 bits, avoiding issues with padding out 1592 // to Size and other such corner cases. 1593 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1; 1594 1595 uint8_t Byte = static_cast<uint8_t>(Value); 1596 1597 for (unsigned i = 1; i < Size; ++i) { 1598 Value >>= 8; 1599 if (static_cast<uint8_t>(Value) != Byte) return -1; 1600 } 1601 return Byte; 1602 } 1603 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) { 1604 // Make sure all array elements are sequences of the same repeated 1605 // byte. 1606 assert(CA->getNumOperands() != 0 && "Should be a CAZ"); 1607 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM); 1608 if (Byte == -1) return -1; 1609 1610 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) { 1611 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM); 1612 if (ThisByte == -1) return -1; 1613 if (Byte != ThisByte) return -1; 1614 } 1615 return Byte; 1616 } 1617 1618 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V)) 1619 return isRepeatedByteSequence(CDS); 1620 1621 return -1; 1622} 1623 1624static void EmitGlobalConstantDataSequential(const ConstantDataSequential *CDS, 1625 unsigned AddrSpace,AsmPrinter &AP){ 1626 1627 // See if we can aggregate this into a .fill, if so, emit it as such. 1628 int Value = isRepeatedByteSequence(CDS, AP.TM); 1629 if (Value != -1) { 1630 uint64_t Bytes = AP.TM.getTargetData()->getTypeAllocSize(CDS->getType()); 1631 // Don't emit a 1-byte object as a .fill. 1632 if (Bytes > 1) 1633 return AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace); 1634 } 1635 1636 // If this can be emitted with .ascii/.asciz, emit it as such. 1637 if (CDS->isString()) 1638 return AP.OutStreamer.EmitBytes(CDS->getAsString(), AddrSpace); 1639 1640 // Otherwise, emit the values in successive locations. 1641 unsigned ElementByteSize = CDS->getElementByteSize(); 1642 if (isa<IntegerType>(CDS->getElementType())) { 1643 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1644 if (AP.isVerbose()) 1645 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n", 1646 CDS->getElementAsInteger(i)); 1647 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i), 1648 ElementByteSize, AddrSpace); 1649 } 1650 } else if (ElementByteSize == 4) { 1651 // FP Constants are printed as integer constants to avoid losing 1652 // precision. 1653 assert(CDS->getElementType()->isFloatTy()); 1654 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1655 union { 1656 float F; 1657 uint32_t I; 1658 }; 1659 1660 F = CDS->getElementAsFloat(i); 1661 if (AP.isVerbose()) 1662 AP.OutStreamer.GetCommentOS() << "float " << F << '\n'; 1663 AP.OutStreamer.EmitIntValue(I, 4, AddrSpace); 1664 } 1665 } else { 1666 assert(CDS->getElementType()->isDoubleTy()); 1667 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1668 union { 1669 double F; 1670 uint64_t I; 1671 }; 1672 1673 F = CDS->getElementAsDouble(i); 1674 if (AP.isVerbose()) 1675 AP.OutStreamer.GetCommentOS() << "double " << F << '\n'; 1676 AP.OutStreamer.EmitIntValue(I, 8, AddrSpace); 1677 } 1678 } 1679 1680 const TargetData &TD = *AP.TM.getTargetData(); 1681 unsigned Size = TD.getTypeAllocSize(CDS->getType()); 1682 unsigned EmittedSize = TD.getTypeAllocSize(CDS->getType()->getElementType()) * 1683 CDS->getNumElements(); 1684 if (unsigned Padding = Size - EmittedSize) 1685 AP.OutStreamer.EmitZeros(Padding, AddrSpace); 1686 1687} 1688 1689static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace, 1690 AsmPrinter &AP) { 1691 // See if we can aggregate some values. Make sure it can be 1692 // represented as a series of bytes of the constant value. 1693 int Value = isRepeatedByteSequence(CA, AP.TM); 1694 1695 if (Value != -1) { 1696 uint64_t Bytes = AP.TM.getTargetData()->getTypeAllocSize(CA->getType()); 1697 AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace); 1698 } 1699 else { 1700 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1701 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP); 1702 } 1703} 1704 1705static void EmitGlobalConstantVector(const ConstantVector *CV, 1706 unsigned AddrSpace, AsmPrinter &AP) { 1707 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i) 1708 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP); 1709 1710 const TargetData &TD = *AP.TM.getTargetData(); 1711 unsigned Size = TD.getTypeAllocSize(CV->getType()); 1712 unsigned EmittedSize = TD.getTypeAllocSize(CV->getType()->getElementType()) * 1713 CV->getType()->getNumElements(); 1714 if (unsigned Padding = Size - EmittedSize) 1715 AP.OutStreamer.EmitZeros(Padding, AddrSpace); 1716} 1717 1718static void EmitGlobalConstantStruct(const ConstantStruct *CS, 1719 unsigned AddrSpace, AsmPrinter &AP) { 1720 // Print the fields in successive locations. Pad to align if needed! 1721 const TargetData *TD = AP.TM.getTargetData(); 1722 unsigned Size = TD->getTypeAllocSize(CS->getType()); 1723 const StructLayout *Layout = TD->getStructLayout(CS->getType()); 1724 uint64_t SizeSoFar = 0; 1725 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 1726 const Constant *Field = CS->getOperand(i); 1727 1728 // Check if padding is needed and insert one or more 0s. 1729 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType()); 1730 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1)) 1731 - Layout->getElementOffset(i)) - FieldSize; 1732 SizeSoFar += FieldSize + PadSize; 1733 1734 // Now print the actual field value. 1735 EmitGlobalConstantImpl(Field, AddrSpace, AP); 1736 1737 // Insert padding - this may include padding to increase the size of the 1738 // current field up to the ABI size (if the struct is not packed) as well 1739 // as padding to ensure that the next field starts at the right offset. 1740 AP.OutStreamer.EmitZeros(PadSize, AddrSpace); 1741 } 1742 assert(SizeSoFar == Layout->getSizeInBytes() && 1743 "Layout of constant struct may be incorrect!"); 1744} 1745 1746static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace, 1747 AsmPrinter &AP) { 1748 if (CFP->getType()->isHalfTy()) { 1749 if (AP.isVerbose()) { 1750 SmallString<10> Str; 1751 CFP->getValueAPF().toString(Str); 1752 AP.OutStreamer.GetCommentOS() << "half " << Str << '\n'; 1753 } 1754 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1755 AP.OutStreamer.EmitIntValue(Val, 2, AddrSpace); 1756 return; 1757 } 1758 1759 if (CFP->getType()->isFloatTy()) { 1760 if (AP.isVerbose()) { 1761 float Val = CFP->getValueAPF().convertToFloat(); 1762 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n'; 1763 } 1764 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1765 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace); 1766 return; 1767 } 1768 1769 // FP Constants are printed as integer constants to avoid losing 1770 // precision. 1771 if (CFP->getType()->isDoubleTy()) { 1772 if (AP.isVerbose()) { 1773 double Val = CFP->getValueAPF().convertToDouble(); 1774 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n'; 1775 } 1776 1777 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1778 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1779 return; 1780 } 1781 1782 if (CFP->getType()->isX86_FP80Ty()) { 1783 // all long double variants are printed as hex 1784 // API needed to prevent premature destruction 1785 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1786 const uint64_t *p = API.getRawData(); 1787 if (AP.isVerbose()) { 1788 // Convert to double so we can print the approximate val as a comment. 1789 APFloat DoubleVal = CFP->getValueAPF(); 1790 bool ignored; 1791 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 1792 &ignored); 1793 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= " 1794 << DoubleVal.convertToDouble() << '\n'; 1795 } 1796 1797 if (AP.TM.getTargetData()->isBigEndian()) { 1798 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1799 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1800 } else { 1801 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1802 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1803 } 1804 1805 // Emit the tail padding for the long double. 1806 const TargetData &TD = *AP.TM.getTargetData(); 1807 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) - 1808 TD.getTypeStoreSize(CFP->getType()), AddrSpace); 1809 return; 1810 } 1811 1812 assert(CFP->getType()->isPPC_FP128Ty() && 1813 "Floating point constant type not handled"); 1814 // All long double variants are printed as hex 1815 // API needed to prevent premature destruction. 1816 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1817 const uint64_t *p = API.getRawData(); 1818 if (AP.TM.getTargetData()->isBigEndian()) { 1819 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1820 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1821 } else { 1822 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1823 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1824 } 1825} 1826 1827static void EmitGlobalConstantLargeInt(const ConstantInt *CI, 1828 unsigned AddrSpace, AsmPrinter &AP) { 1829 const TargetData *TD = AP.TM.getTargetData(); 1830 unsigned BitWidth = CI->getBitWidth(); 1831 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits"); 1832 1833 // We don't expect assemblers to support integer data directives 1834 // for more than 64 bits, so we emit the data in at most 64-bit 1835 // quantities at a time. 1836 const uint64_t *RawData = CI->getValue().getRawData(); 1837 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) { 1838 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i]; 1839 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1840 } 1841} 1842 1843static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace, 1844 AsmPrinter &AP) { 1845 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) { 1846 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1847 return AP.OutStreamer.EmitZeros(Size, AddrSpace); 1848 } 1849 1850 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { 1851 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1852 switch (Size) { 1853 case 1: 1854 case 2: 1855 case 4: 1856 case 8: 1857 if (AP.isVerbose()) 1858 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n", 1859 CI->getZExtValue()); 1860 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace); 1861 return; 1862 default: 1863 EmitGlobalConstantLargeInt(CI, AddrSpace, AP); 1864 return; 1865 } 1866 } 1867 1868 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) 1869 return EmitGlobalConstantFP(CFP, AddrSpace, AP); 1870 1871 if (isa<ConstantPointerNull>(CV)) { 1872 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1873 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace); 1874 return; 1875 } 1876 1877 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV)) 1878 return EmitGlobalConstantDataSequential(CDS, AddrSpace, AP); 1879 1880 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) 1881 return EmitGlobalConstantArray(CVA, AddrSpace, AP); 1882 1883 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) 1884 return EmitGlobalConstantStruct(CVS, AddrSpace, AP); 1885 1886 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of 1887 // vectors). 1888 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) 1889 if (CE->getOpcode() == Instruction::BitCast) 1890 return EmitGlobalConstantImpl(CE->getOperand(0), AddrSpace, AP); 1891 1892 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV)) 1893 return EmitGlobalConstantVector(V, AddrSpace, AP); 1894 1895 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it 1896 // thread the streamer with EmitValue. 1897 AP.OutStreamer.EmitValue(LowerConstant(CV, AP), 1898 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()), 1899 AddrSpace); 1900} 1901 1902/// EmitGlobalConstant - Print a general LLVM constant to the .s file. 1903void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) { 1904 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1905 if (Size) 1906 EmitGlobalConstantImpl(CV, AddrSpace, *this); 1907 else if (MAI->hasSubsectionsViaSymbols()) { 1908 // If the global has zero size, emit a single byte so that two labels don't 1909 // look like they are at the same location. 1910 OutStreamer.EmitIntValue(0, 1, AddrSpace); 1911 } 1912} 1913 1914void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 1915 // Target doesn't support this yet! 1916 llvm_unreachable("Target does not support EmitMachineConstantPoolValue"); 1917} 1918 1919void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const { 1920 if (Offset > 0) 1921 OS << '+' << Offset; 1922 else if (Offset < 0) 1923 OS << Offset; 1924} 1925 1926//===----------------------------------------------------------------------===// 1927// Symbol Lowering Routines. 1928//===----------------------------------------------------------------------===// 1929 1930/// GetTempSymbol - Return the MCSymbol corresponding to the assembler 1931/// temporary label with the specified stem and unique ID. 1932MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const { 1933 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + 1934 Name + Twine(ID)); 1935} 1936 1937/// GetTempSymbol - Return an assembler temporary label with the specified 1938/// stem. 1939MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const { 1940 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+ 1941 Name); 1942} 1943 1944 1945MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const { 1946 return MMI->getAddrLabelSymbol(BA->getBasicBlock()); 1947} 1948 1949MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const { 1950 return MMI->getAddrLabelSymbol(BB); 1951} 1952 1953/// GetCPISymbol - Return the symbol for the specified constant pool entry. 1954MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const { 1955 return OutContext.GetOrCreateSymbol 1956 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber()) 1957 + "_" + Twine(CPID)); 1958} 1959 1960/// GetJTISymbol - Return the symbol for the specified jump table entry. 1961MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const { 1962 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate); 1963} 1964 1965/// GetJTSetSymbol - Return the symbol for the specified jump table .set 1966/// FIXME: privatize to AsmPrinter. 1967MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const { 1968 return OutContext.GetOrCreateSymbol 1969 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" + 1970 Twine(UID) + "_set_" + Twine(MBBID)); 1971} 1972 1973/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with 1974/// global value name as its base, with the specified suffix, and where the 1975/// symbol is forced to have private linkage if ForcePrivate is true. 1976MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV, 1977 StringRef Suffix, 1978 bool ForcePrivate) const { 1979 SmallString<60> NameStr; 1980 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate); 1981 NameStr.append(Suffix.begin(), Suffix.end()); 1982 return OutContext.GetOrCreateSymbol(NameStr.str()); 1983} 1984 1985/// GetExternalSymbolSymbol - Return the MCSymbol for the specified 1986/// ExternalSymbol. 1987MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const { 1988 SmallString<60> NameStr; 1989 Mang->getNameWithPrefix(NameStr, Sym); 1990 return OutContext.GetOrCreateSymbol(NameStr.str()); 1991} 1992 1993 1994 1995/// PrintParentLoopComment - Print comments about parent loops of this one. 1996static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1997 unsigned FunctionNumber) { 1998 if (Loop == 0) return; 1999 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber); 2000 OS.indent(Loop->getLoopDepth()*2) 2001 << "Parent Loop BB" << FunctionNumber << "_" 2002 << Loop->getHeader()->getNumber() 2003 << " Depth=" << Loop->getLoopDepth() << '\n'; 2004} 2005 2006 2007/// PrintChildLoopComment - Print comments about child loops within 2008/// the loop for this basic block, with nesting. 2009static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop, 2010 unsigned FunctionNumber) { 2011 // Add child loop information 2012 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){ 2013 OS.indent((*CL)->getLoopDepth()*2) 2014 << "Child Loop BB" << FunctionNumber << "_" 2015 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth() 2016 << '\n'; 2017 PrintChildLoopComment(OS, *CL, FunctionNumber); 2018 } 2019} 2020 2021/// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks. 2022static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB, 2023 const MachineLoopInfo *LI, 2024 const AsmPrinter &AP) { 2025 // Add loop depth information 2026 const MachineLoop *Loop = LI->getLoopFor(&MBB); 2027 if (Loop == 0) return; 2028 2029 MachineBasicBlock *Header = Loop->getHeader(); 2030 assert(Header && "No header for loop"); 2031 2032 // If this block is not a loop header, just print out what is the loop header 2033 // and return. 2034 if (Header != &MBB) { 2035 AP.OutStreamer.AddComment(" in Loop: Header=BB" + 2036 Twine(AP.getFunctionNumber())+"_" + 2037 Twine(Loop->getHeader()->getNumber())+ 2038 " Depth="+Twine(Loop->getLoopDepth())); 2039 return; 2040 } 2041 2042 // Otherwise, it is a loop header. Print out information about child and 2043 // parent loops. 2044 raw_ostream &OS = AP.OutStreamer.GetCommentOS(); 2045 2046 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 2047 2048 OS << "=>"; 2049 OS.indent(Loop->getLoopDepth()*2-2); 2050 2051 OS << "This "; 2052 if (Loop->empty()) 2053 OS << "Inner "; 2054 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n'; 2055 2056 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber()); 2057} 2058 2059 2060/// EmitBasicBlockStart - This method prints the label for the specified 2061/// MachineBasicBlock, an alignment (if present) and a comment describing 2062/// it if appropriate. 2063void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const { 2064 // Emit an alignment directive for this block, if needed. 2065 if (unsigned Align = MBB->getAlignment()) 2066 EmitAlignment(Align); 2067 2068 // If the block has its address taken, emit any labels that were used to 2069 // reference the block. It is possible that there is more than one label 2070 // here, because multiple LLVM BB's may have been RAUW'd to this block after 2071 // the references were generated. 2072 if (MBB->hasAddressTaken()) { 2073 const BasicBlock *BB = MBB->getBasicBlock(); 2074 if (isVerbose()) 2075 OutStreamer.AddComment("Block address taken"); 2076 2077 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB); 2078 2079 for (unsigned i = 0, e = Syms.size(); i != e; ++i) 2080 OutStreamer.EmitLabel(Syms[i]); 2081 } 2082 2083 // Print the main label for the block. 2084 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) { 2085 if (isVerbose() && OutStreamer.hasRawTextSupport()) { 2086 if (const BasicBlock *BB = MBB->getBasicBlock()) 2087 if (BB->hasName()) 2088 OutStreamer.AddComment("%" + BB->getName()); 2089 2090 EmitBasicBlockLoopComments(*MBB, LI, *this); 2091 2092 // NOTE: Want this comment at start of line, don't emit with AddComment. 2093 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" + 2094 Twine(MBB->getNumber()) + ":"); 2095 } 2096 } else { 2097 if (isVerbose()) { 2098 if (const BasicBlock *BB = MBB->getBasicBlock()) 2099 if (BB->hasName()) 2100 OutStreamer.AddComment("%" + BB->getName()); 2101 EmitBasicBlockLoopComments(*MBB, LI, *this); 2102 } 2103 2104 OutStreamer.EmitLabel(MBB->getSymbol()); 2105 } 2106} 2107 2108void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility, 2109 bool IsDefinition) const { 2110 MCSymbolAttr Attr = MCSA_Invalid; 2111 2112 switch (Visibility) { 2113 default: break; 2114 case GlobalValue::HiddenVisibility: 2115 if (IsDefinition) 2116 Attr = MAI->getHiddenVisibilityAttr(); 2117 else 2118 Attr = MAI->getHiddenDeclarationVisibilityAttr(); 2119 break; 2120 case GlobalValue::ProtectedVisibility: 2121 Attr = MAI->getProtectedVisibilityAttr(); 2122 break; 2123 } 2124 2125 if (Attr != MCSA_Invalid) 2126 OutStreamer.EmitSymbolAttribute(Sym, Attr); 2127} 2128 2129/// isBlockOnlyReachableByFallthough - Return true if the basic block has 2130/// exactly one predecessor and the control transfer mechanism between 2131/// the predecessor and this block is a fall-through. 2132bool AsmPrinter:: 2133isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const { 2134 // If this is a landing pad, it isn't a fall through. If it has no preds, 2135 // then nothing falls through to it. 2136 if (MBB->isLandingPad() || MBB->pred_empty()) 2137 return false; 2138 2139 // If there isn't exactly one predecessor, it can't be a fall through. 2140 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI; 2141 ++PI2; 2142 if (PI2 != MBB->pred_end()) 2143 return false; 2144 2145 // The predecessor has to be immediately before this block. 2146 MachineBasicBlock *Pred = *PI; 2147 2148 if (!Pred->isLayoutSuccessor(MBB)) 2149 return false; 2150 2151 // If the block is completely empty, then it definitely does fall through. 2152 if (Pred->empty()) 2153 return true; 2154 2155 // Check the terminators in the previous blocks 2156 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(), 2157 IE = Pred->end(); II != IE; ++II) { 2158 MachineInstr &MI = *II; 2159 2160 // If it is not a simple branch, we are in a table somewhere. 2161 if (!MI.isBranch() || MI.isIndirectBranch()) 2162 return false; 2163 2164 // If we are the operands of one of the branches, this is not 2165 // a fall through. 2166 for (MachineInstr::mop_iterator OI = MI.operands_begin(), 2167 OE = MI.operands_end(); OI != OE; ++OI) { 2168 const MachineOperand& OP = *OI; 2169 if (OP.isJTI()) 2170 return false; 2171 if (OP.isMBB() && OP.getMBB() == MBB) 2172 return false; 2173 } 2174 } 2175 2176 return true; 2177} 2178 2179 2180 2181GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) { 2182 if (!S->usesMetadata()) 2183 return 0; 2184 2185 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 2186 gcp_map_type::iterator GCPI = GCMap.find(S); 2187 if (GCPI != GCMap.end()) 2188 return GCPI->second; 2189 2190 const char *Name = S->getName().c_str(); 2191 2192 for (GCMetadataPrinterRegistry::iterator 2193 I = GCMetadataPrinterRegistry::begin(), 2194 E = GCMetadataPrinterRegistry::end(); I != E; ++I) 2195 if (strcmp(Name, I->getName()) == 0) { 2196 GCMetadataPrinter *GMP = I->instantiate(); 2197 GMP->S = S; 2198 GCMap.insert(std::make_pair(S, GMP)); 2199 return GMP; 2200 } 2201 2202 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name)); 2203} 2204