AsmPrinter.cpp revision 39646d96e76aea5d20bffb386233a0dbb5932a21
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/DebugInfo.h" 19#include "llvm/Module.h" 20#include "llvm/CodeGen/GCMetadataPrinter.h" 21#include "llvm/CodeGen/MachineConstantPool.h" 22#include "llvm/CodeGen/MachineFrameInfo.h" 23#include "llvm/CodeGen/MachineFunction.h" 24#include "llvm/CodeGen/MachineJumpTableInfo.h" 25#include "llvm/CodeGen/MachineLoopInfo.h" 26#include "llvm/CodeGen/MachineModuleInfo.h" 27#include "llvm/Analysis/ConstantFolding.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 CurrentFnSym = CurrentFnSymForSize = 0; 104 GCMetadataPrinters = 0; 105 VerboseAsm = Streamer.isVerboseAsm(); 106} 107 108AsmPrinter::~AsmPrinter() { 109 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized"); 110 111 if (GCMetadataPrinters != 0) { 112 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 113 114 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I) 115 delete I->second; 116 delete &GCMap; 117 GCMetadataPrinters = 0; 118 } 119 120 delete &OutStreamer; 121} 122 123/// getFunctionNumber - Return a unique ID for the current function. 124/// 125unsigned AsmPrinter::getFunctionNumber() const { 126 return MF->getFunctionNumber(); 127} 128 129const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const { 130 return TM.getTargetLowering()->getObjFileLowering(); 131} 132 133 134/// getTargetData - Return information about data layout. 135const TargetData &AsmPrinter::getTargetData() const { 136 return *TM.getTargetData(); 137} 138 139/// getCurrentSection() - Return the current section we are emitting to. 140const MCSection *AsmPrinter::getCurrentSection() const { 141 return OutStreamer.getCurrentSection(); 142} 143 144 145 146void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const { 147 AU.setPreservesAll(); 148 MachineFunctionPass::getAnalysisUsage(AU); 149 AU.addRequired<MachineModuleInfo>(); 150 AU.addRequired<GCModuleInfo>(); 151 if (isVerbose()) 152 AU.addRequired<MachineLoopInfo>(); 153} 154 155bool AsmPrinter::doInitialization(Module &M) { 156 MMI = getAnalysisIfAvailable<MachineModuleInfo>(); 157 MMI->AnalyzeModule(M); 158 159 // Initialize TargetLoweringObjectFile. 160 const_cast<TargetLoweringObjectFile&>(getObjFileLowering()) 161 .Initialize(OutContext, TM); 162 163 Mang = new Mangler(OutContext, *TM.getTargetData()); 164 165 // Allow the target to emit any magic that it wants at the start of the file. 166 EmitStartOfAsmFile(M); 167 168 // Very minimal debug info. It is ignored if we emit actual debug info. If we 169 // don't, this at least helps the user find where a global came from. 170 if (MAI->hasSingleParameterDotFile()) { 171 // .file "foo.c" 172 OutStreamer.EmitFileDirective(M.getModuleIdentifier()); 173 } 174 175 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 176 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 177 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I) 178 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I)) 179 MP->beginAssembly(*this); 180 181 // Emit module-level inline asm if it exists. 182 if (!M.getModuleInlineAsm().empty()) { 183 OutStreamer.AddComment("Start of file scope inline assembly"); 184 OutStreamer.AddBlankLine(); 185 EmitInlineAsm(M.getModuleInlineAsm()+"\n"); 186 OutStreamer.AddComment("End of file scope inline assembly"); 187 OutStreamer.AddBlankLine(); 188 } 189 190 if (MAI->doesSupportDebugInformation()) 191 DD = new DwarfDebug(this, &M); 192 193 switch (MAI->getExceptionHandlingType()) { 194 case ExceptionHandling::None: 195 return false; 196 case ExceptionHandling::SjLj: 197 case ExceptionHandling::DwarfCFI: 198 DE = new DwarfCFIException(this); 199 return false; 200 case ExceptionHandling::ARM: 201 DE = new ARMException(this); 202 return false; 203 case ExceptionHandling::Win64: 204 DE = new Win64Exception(this); 205 return false; 206 } 207 208 llvm_unreachable("Unknown exception type."); 209} 210 211void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const { 212 switch ((GlobalValue::LinkageTypes)Linkage) { 213 case GlobalValue::CommonLinkage: 214 case GlobalValue::LinkOnceAnyLinkage: 215 case GlobalValue::LinkOnceODRLinkage: 216 case GlobalValue::LinkOnceODRAutoHideLinkage: 217 case GlobalValue::WeakAnyLinkage: 218 case GlobalValue::WeakODRLinkage: 219 case GlobalValue::LinkerPrivateWeakLinkage: 220 if (MAI->getWeakDefDirective() != 0) { 221 // .globl _foo 222 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 223 224 if ((GlobalValue::LinkageTypes)Linkage != 225 GlobalValue::LinkOnceODRAutoHideLinkage) 226 // .weak_definition _foo 227 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition); 228 else 229 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate); 230 } else if (MAI->getLinkOnceDirective() != 0) { 231 // .globl _foo 232 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 233 //NOTE: linkonce is handled by the section the symbol was assigned to. 234 } else { 235 // .weak _foo 236 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak); 237 } 238 break; 239 case GlobalValue::DLLExportLinkage: 240 case GlobalValue::AppendingLinkage: 241 // FIXME: appending linkage variables should go into a section of 242 // their name or something. For now, just emit them as external. 243 case GlobalValue::ExternalLinkage: 244 // If external or appending, declare as a global symbol. 245 // .globl _foo 246 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 247 break; 248 case GlobalValue::PrivateLinkage: 249 case GlobalValue::InternalLinkage: 250 case GlobalValue::LinkerPrivateLinkage: 251 break; 252 default: 253 llvm_unreachable("Unknown linkage type!"); 254 } 255} 256 257 258/// EmitGlobalVariable - Emit the specified global variable to the .s file. 259void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) { 260 if (GV->hasInitializer()) { 261 // Check to see if this is a special global used by LLVM, if so, emit it. 262 if (EmitSpecialLLVMGlobal(GV)) 263 return; 264 265 if (isVerbose()) { 266 WriteAsOperand(OutStreamer.GetCommentOS(), GV, 267 /*PrintType=*/false, GV->getParent()); 268 OutStreamer.GetCommentOS() << '\n'; 269 } 270 } 271 272 MCSymbol *GVSym = Mang->getSymbol(GV); 273 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration()); 274 275 if (!GV->hasInitializer()) // External globals require no extra code. 276 return; 277 278 if (MAI->hasDotTypeDotSizeDirective()) 279 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject); 280 281 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM); 282 283 const TargetData *TD = TM.getTargetData(); 284 uint64_t Size = TD->getTypeAllocSize(GV->getType()->getElementType()); 285 286 // If the alignment is specified, we *must* obey it. Overaligning a global 287 // with a specified alignment is a prompt way to break globals emitted to 288 // sections and expected to be contiguous (e.g. ObjC metadata). 289 unsigned AlignLog = getGVAlignmentLog2(GV, *TD); 290 291 // Handle common and BSS local symbols (.lcomm). 292 if (GVKind.isCommon() || GVKind.isBSSLocal()) { 293 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. 294 unsigned Align = 1 << AlignLog; 295 296 // Handle common symbols. 297 if (GVKind.isCommon()) { 298 if (!getObjFileLowering().getCommDirectiveSupportsAlignment()) 299 Align = 0; 300 301 // .comm _foo, 42, 4 302 OutStreamer.EmitCommonSymbol(GVSym, Size, Align); 303 return; 304 } 305 306 // Handle local BSS symbols. 307 if (MAI->hasMachoZeroFillDirective()) { 308 const MCSection *TheSection = 309 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 310 // .zerofill __DATA, __bss, _foo, 400, 5 311 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align); 312 return; 313 } 314 315 if (Align == 1 || MAI->getLCOMMDirectiveSupportsAlignment()) { 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 return OutStreamer.EmitLabel(CurrentFnSym); 479 480 report_fatal_error("'" + Twine(CurrentFnSym->getName()) + 481 "' label emitted multiple times to assembly file"); 482} 483 484 485/// EmitComments - Pretty-print comments for instructions. 486static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) { 487 const MachineFunction *MF = MI.getParent()->getParent(); 488 const TargetMachine &TM = MF->getTarget(); 489 490 // Check for spills and reloads 491 int FI; 492 493 const MachineFrameInfo *FrameInfo = MF->getFrameInfo(); 494 495 // We assume a single instruction only has a spill or reload, not 496 // both. 497 const MachineMemOperand *MMO; 498 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) { 499 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 500 MMO = *MI.memoperands_begin(); 501 CommentOS << MMO->getSize() << "-byte Reload\n"; 502 } 503 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) { 504 if (FrameInfo->isSpillSlotObjectIndex(FI)) 505 CommentOS << MMO->getSize() << "-byte Folded Reload\n"; 506 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) { 507 if (FrameInfo->isSpillSlotObjectIndex(FI)) { 508 MMO = *MI.memoperands_begin(); 509 CommentOS << MMO->getSize() << "-byte Spill\n"; 510 } 511 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) { 512 if (FrameInfo->isSpillSlotObjectIndex(FI)) 513 CommentOS << MMO->getSize() << "-byte Folded Spill\n"; 514 } 515 516 // Check for spill-induced copies 517 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse)) 518 CommentOS << " Reload Reuse\n"; 519} 520 521/// EmitImplicitDef - This method emits the specified machine instruction 522/// that is an implicit def. 523static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) { 524 unsigned RegNo = MI->getOperand(0).getReg(); 525 AP.OutStreamer.AddComment(Twine("implicit-def: ") + 526 AP.TM.getRegisterInfo()->getName(RegNo)); 527 AP.OutStreamer.AddBlankLine(); 528} 529 530static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) { 531 std::string Str = "kill:"; 532 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 533 const MachineOperand &Op = MI->getOperand(i); 534 assert(Op.isReg() && "KILL instruction must have only register operands"); 535 Str += ' '; 536 Str += AP.TM.getRegisterInfo()->getName(Op.getReg()); 537 Str += (Op.isDef() ? "<def>" : "<kill>"); 538 } 539 AP.OutStreamer.AddComment(Str); 540 AP.OutStreamer.AddBlankLine(); 541} 542 543/// EmitDebugValueComment - This method handles the target-independent form 544/// of DBG_VALUE, returning true if it was able to do so. A false return 545/// means the target will need to handle MI in EmitInstruction. 546static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) { 547 // This code handles only the 3-operand target-independent form. 548 if (MI->getNumOperands() != 3) 549 return false; 550 551 SmallString<128> Str; 552 raw_svector_ostream OS(Str); 553 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: "; 554 555 // cast away const; DIetc do not take const operands for some reason. 556 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata())); 557 if (V.getContext().isSubprogram()) 558 OS << DISubprogram(V.getContext()).getDisplayName() << ":"; 559 OS << V.getName() << " <- "; 560 561 // Register or immediate value. Register 0 means undef. 562 if (MI->getOperand(0).isFPImm()) { 563 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF()); 564 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) { 565 OS << (double)APF.convertToFloat(); 566 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) { 567 OS << APF.convertToDouble(); 568 } else { 569 // There is no good way to print long double. Convert a copy to 570 // double. Ah well, it's only a comment. 571 bool ignored; 572 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 573 &ignored); 574 OS << "(long double) " << APF.convertToDouble(); 575 } 576 } else if (MI->getOperand(0).isImm()) { 577 OS << MI->getOperand(0).getImm(); 578 } else if (MI->getOperand(0).isCImm()) { 579 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/); 580 } else { 581 assert(MI->getOperand(0).isReg() && "Unknown operand type"); 582 if (MI->getOperand(0).getReg() == 0) { 583 // Suppress offset, it is not meaningful here. 584 OS << "undef"; 585 // NOTE: Want this comment at start of line, don't emit with AddComment. 586 AP.OutStreamer.EmitRawText(OS.str()); 587 return true; 588 } 589 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg()); 590 } 591 592 OS << '+' << MI->getOperand(1).getImm(); 593 // NOTE: Want this comment at start of line, don't emit with AddComment. 594 AP.OutStreamer.EmitRawText(OS.str()); 595 return true; 596} 597 598AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() { 599 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI && 600 MF->getFunction()->needsUnwindTableEntry()) 601 return CFI_M_EH; 602 603 if (MMI->hasDebugInfo()) 604 return CFI_M_Debug; 605 606 return CFI_M_None; 607} 608 609bool AsmPrinter::needsSEHMoves() { 610 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 && 611 MF->getFunction()->needsUnwindTableEntry(); 612} 613 614bool AsmPrinter::needsRelocationsForDwarfStringPool() const { 615 return MAI->doesDwarfUseRelocationsAcrossSections(); 616} 617 618void AsmPrinter::emitPrologLabel(const MachineInstr &MI) { 619 MCSymbol *Label = MI.getOperand(0).getMCSymbol(); 620 621 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI) 622 return; 623 624 if (needsCFIMoves() == CFI_M_None) 625 return; 626 627 if (MMI->getCompactUnwindEncoding() != 0) 628 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding()); 629 630 MachineModuleInfo &MMI = MF->getMMI(); 631 std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 632 bool FoundOne = false; 633 (void)FoundOne; 634 for (std::vector<MachineMove>::iterator I = Moves.begin(), 635 E = Moves.end(); I != E; ++I) { 636 if (I->getLabel() == Label) { 637 EmitCFIFrameMove(*I); 638 FoundOne = true; 639 } 640 } 641 assert(FoundOne); 642} 643 644/// EmitFunctionBody - This method emits the body and trailer for a 645/// function. 646void AsmPrinter::EmitFunctionBody() { 647 // Emit target-specific gunk before the function body. 648 EmitFunctionBodyStart(); 649 650 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo(); 651 652 // Print out code for the function. 653 bool HasAnyRealCode = false; 654 const MachineInstr *LastMI = 0; 655 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 656 I != E; ++I) { 657 // Print a label for the basic block. 658 EmitBasicBlockStart(I); 659 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 660 II != IE; ++II) { 661 LastMI = II; 662 663 // Print the assembly for the instruction. 664 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() && 665 !II->isDebugValue()) { 666 HasAnyRealCode = true; 667 ++EmittedInsts; 668 } 669 670 if (ShouldPrintDebugScopes) { 671 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 672 DD->beginInstruction(II); 673 } 674 675 if (isVerbose()) 676 EmitComments(*II, OutStreamer.GetCommentOS()); 677 678 switch (II->getOpcode()) { 679 case TargetOpcode::PROLOG_LABEL: 680 emitPrologLabel(*II); 681 break; 682 683 case TargetOpcode::EH_LABEL: 684 case TargetOpcode::GC_LABEL: 685 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol()); 686 break; 687 case TargetOpcode::INLINEASM: 688 EmitInlineAsm(II); 689 break; 690 case TargetOpcode::DBG_VALUE: 691 if (isVerbose()) { 692 if (!EmitDebugValueComment(II, *this)) 693 EmitInstruction(II); 694 } 695 break; 696 case TargetOpcode::IMPLICIT_DEF: 697 if (isVerbose()) EmitImplicitDef(II, *this); 698 break; 699 case TargetOpcode::KILL: 700 if (isVerbose()) EmitKill(II, *this); 701 break; 702 default: 703 if (!TM.hasMCUseLoc()) 704 MCLineEntry::Make(&OutStreamer, getCurrentSection()); 705 706 EmitInstruction(II); 707 break; 708 } 709 710 if (ShouldPrintDebugScopes) { 711 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 712 DD->endInstruction(II); 713 } 714 } 715 } 716 717 // If the last instruction was a prolog label, then we have a situation where 718 // we emitted a prolog but no function body. This results in the ending prolog 719 // label equaling the end of function label and an invalid "row" in the 720 // FDE. We need to emit a noop in this situation so that the FDE's rows are 721 // valid. 722 bool RequiresNoop = LastMI && LastMI->isPrologLabel(); 723 724 // If the function is empty and the object file uses .subsections_via_symbols, 725 // then we need to emit *something* to the function body to prevent the 726 // labels from collapsing together. Just emit a noop. 727 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) { 728 MCInst Noop; 729 TM.getInstrInfo()->getNoopForMachoTarget(Noop); 730 if (Noop.getOpcode()) { 731 OutStreamer.AddComment("avoids zero-length function"); 732 OutStreamer.EmitInstruction(Noop); 733 } else // Target not mc-ized yet. 734 OutStreamer.EmitRawText(StringRef("\tnop\n")); 735 } 736 737 const Function *F = MF->getFunction(); 738 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) { 739 const BasicBlock *BB = i; 740 if (!BB->hasAddressTaken()) 741 continue; 742 MCSymbol *Sym = GetBlockAddressSymbol(BB); 743 if (Sym->isDefined()) 744 continue; 745 OutStreamer.AddComment("Address of block that was removed by CodeGen"); 746 OutStreamer.EmitLabel(Sym); 747 } 748 749 // Emit target-specific gunk after the function body. 750 EmitFunctionBodyEnd(); 751 752 // If the target wants a .size directive for the size of the function, emit 753 // it. 754 if (MAI->hasDotTypeDotSizeDirective()) { 755 // Create a symbol for the end of function, so we can get the size as 756 // difference between the function label and the temp label. 757 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol(); 758 OutStreamer.EmitLabel(FnEndLabel); 759 760 const MCExpr *SizeExp = 761 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext), 762 MCSymbolRefExpr::Create(CurrentFnSymForSize, 763 OutContext), 764 OutContext); 765 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp); 766 } 767 768 // Emit post-function debug information. 769 if (DD) { 770 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 771 DD->endFunction(MF); 772 } 773 if (DE) { 774 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 775 DE->EndFunction(); 776 } 777 MMI->EndFunction(); 778 779 // Print out jump tables referenced by the function. 780 EmitJumpTableInfo(); 781 782 OutStreamer.AddBlankLine(); 783} 784 785/// getDebugValueLocation - Get location information encoded by DBG_VALUE 786/// operands. 787MachineLocation AsmPrinter:: 788getDebugValueLocation(const MachineInstr *MI) const { 789 // Target specific DBG_VALUE instructions are handled by each target. 790 return MachineLocation(); 791} 792 793/// EmitDwarfRegOp - Emit dwarf register operation. 794void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const { 795 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 796 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false); 797 798 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0; 799 ++SR) { 800 Reg = TRI->getDwarfRegNum(*SR, false); 801 // FIXME: Get the bit range this register uses of the superregister 802 // so that we can produce a DW_OP_bit_piece 803 } 804 805 // FIXME: Handle cases like a super register being encoded as 806 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33 807 808 // FIXME: We have no reasonable way of handling errors in here. The 809 // caller might be in the middle of an dwarf expression. We should 810 // probably assert that Reg >= 0 once debug info generation is more mature. 811 812 if (int Offset = MLoc.getOffset()) { 813 if (Reg < 32) { 814 OutStreamer.AddComment( 815 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg)); 816 EmitInt8(dwarf::DW_OP_breg0 + Reg); 817 } else { 818 OutStreamer.AddComment("DW_OP_bregx"); 819 EmitInt8(dwarf::DW_OP_bregx); 820 OutStreamer.AddComment(Twine(Reg)); 821 EmitULEB128(Reg); 822 } 823 EmitSLEB128(Offset); 824 } else { 825 if (Reg < 32) { 826 OutStreamer.AddComment( 827 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg)); 828 EmitInt8(dwarf::DW_OP_reg0 + Reg); 829 } else { 830 OutStreamer.AddComment("DW_OP_regx"); 831 EmitInt8(dwarf::DW_OP_regx); 832 OutStreamer.AddComment(Twine(Reg)); 833 EmitULEB128(Reg); 834 } 835 } 836 837 // FIXME: Produce a DW_OP_bit_piece if we used a superregister 838} 839 840bool AsmPrinter::doFinalization(Module &M) { 841 // Emit global variables. 842 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 843 I != E; ++I) 844 EmitGlobalVariable(I); 845 846 // Emit visibility info for declarations 847 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 848 const Function &F = *I; 849 if (!F.isDeclaration()) 850 continue; 851 GlobalValue::VisibilityTypes V = F.getVisibility(); 852 if (V == GlobalValue::DefaultVisibility) 853 continue; 854 855 MCSymbol *Name = Mang->getSymbol(&F); 856 EmitVisibility(Name, V, false); 857 } 858 859 // Emit module flags. 860 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags; 861 M.getModuleFlagsMetadata(ModuleFlags); 862 if (!ModuleFlags.empty()) 863 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM); 864 865 // Finalize debug and EH information. 866 if (DE) { 867 { 868 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 869 DE->EndModule(); 870 } 871 delete DE; DE = 0; 872 } 873 if (DD) { 874 { 875 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 876 DD->endModule(); 877 } 878 delete DD; DD = 0; 879 } 880 881 // If the target wants to know about weak references, print them all. 882 if (MAI->getWeakRefDirective()) { 883 // FIXME: This is not lazy, it would be nice to only print weak references 884 // to stuff that is actually used. Note that doing so would require targets 885 // to notice uses in operands (due to constant exprs etc). This should 886 // happen with the MC stuff eventually. 887 888 // Print out module-level global variables here. 889 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 890 I != E; ++I) { 891 if (!I->hasExternalWeakLinkage()) continue; 892 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 893 } 894 895 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 896 if (!I->hasExternalWeakLinkage()) continue; 897 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 898 } 899 } 900 901 if (MAI->hasSetDirective()) { 902 OutStreamer.AddBlankLine(); 903 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end(); 904 I != E; ++I) { 905 MCSymbol *Name = Mang->getSymbol(I); 906 907 const GlobalValue *GV = I->getAliasedGlobal(); 908 MCSymbol *Target = Mang->getSymbol(GV); 909 910 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective()) 911 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global); 912 else if (I->hasWeakLinkage()) 913 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference); 914 else 915 assert(I->hasLocalLinkage() && "Invalid alias linkage"); 916 917 EmitVisibility(Name, I->getVisibility()); 918 919 // Emit the directives as assignments aka .set: 920 OutStreamer.EmitAssignment(Name, 921 MCSymbolRefExpr::Create(Target, OutContext)); 922 } 923 } 924 925 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 926 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 927 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; ) 928 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I)) 929 MP->finishAssembly(*this); 930 931 // If we don't have any trampolines, then we don't require stack memory 932 // to be executable. Some targets have a directive to declare this. 933 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline"); 934 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty()) 935 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext)) 936 OutStreamer.SwitchSection(S); 937 938 // Allow the target to emit any magic that it wants at the end of the file, 939 // after everything else has gone out. 940 EmitEndOfAsmFile(M); 941 942 delete Mang; Mang = 0; 943 MMI = 0; 944 945 OutStreamer.Finish(); 946 return false; 947} 948 949void AsmPrinter::SetupMachineFunction(MachineFunction &MF) { 950 this->MF = &MF; 951 // Get the function symbol. 952 CurrentFnSym = Mang->getSymbol(MF.getFunction()); 953 CurrentFnSymForSize = CurrentFnSym; 954 955 if (isVerbose()) 956 LI = &getAnalysis<MachineLoopInfo>(); 957} 958 959namespace { 960 // SectionCPs - Keep track the alignment, constpool entries per Section. 961 struct SectionCPs { 962 const MCSection *S; 963 unsigned Alignment; 964 SmallVector<unsigned, 4> CPEs; 965 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {} 966 }; 967} 968 969/// EmitConstantPool - Print to the current output stream assembly 970/// representations of the constants in the constant pool MCP. This is 971/// used to print out constants which have been "spilled to memory" by 972/// the code generator. 973/// 974void AsmPrinter::EmitConstantPool() { 975 const MachineConstantPool *MCP = MF->getConstantPool(); 976 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants(); 977 if (CP.empty()) return; 978 979 // Calculate sections for constant pool entries. We collect entries to go into 980 // the same section together to reduce amount of section switch statements. 981 SmallVector<SectionCPs, 4> CPSections; 982 for (unsigned i = 0, e = CP.size(); i != e; ++i) { 983 const MachineConstantPoolEntry &CPE = CP[i]; 984 unsigned Align = CPE.getAlignment(); 985 986 SectionKind Kind; 987 switch (CPE.getRelocationInfo()) { 988 default: llvm_unreachable("Unknown section kind"); 989 case 2: Kind = SectionKind::getReadOnlyWithRel(); break; 990 case 1: 991 Kind = SectionKind::getReadOnlyWithRelLocal(); 992 break; 993 case 0: 994 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) { 995 case 4: Kind = SectionKind::getMergeableConst4(); break; 996 case 8: Kind = SectionKind::getMergeableConst8(); break; 997 case 16: Kind = SectionKind::getMergeableConst16();break; 998 default: Kind = SectionKind::getMergeableConst(); break; 999 } 1000 } 1001 1002 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind); 1003 1004 // The number of sections are small, just do a linear search from the 1005 // last section to the first. 1006 bool Found = false; 1007 unsigned SecIdx = CPSections.size(); 1008 while (SecIdx != 0) { 1009 if (CPSections[--SecIdx].S == S) { 1010 Found = true; 1011 break; 1012 } 1013 } 1014 if (!Found) { 1015 SecIdx = CPSections.size(); 1016 CPSections.push_back(SectionCPs(S, Align)); 1017 } 1018 1019 if (Align > CPSections[SecIdx].Alignment) 1020 CPSections[SecIdx].Alignment = Align; 1021 CPSections[SecIdx].CPEs.push_back(i); 1022 } 1023 1024 // Now print stuff into the calculated sections. 1025 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) { 1026 OutStreamer.SwitchSection(CPSections[i].S); 1027 EmitAlignment(Log2_32(CPSections[i].Alignment)); 1028 1029 unsigned Offset = 0; 1030 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) { 1031 unsigned CPI = CPSections[i].CPEs[j]; 1032 MachineConstantPoolEntry CPE = CP[CPI]; 1033 1034 // Emit inter-object padding for alignment. 1035 unsigned AlignMask = CPE.getAlignment() - 1; 1036 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask; 1037 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/); 1038 1039 Type *Ty = CPE.getType(); 1040 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty); 1041 OutStreamer.EmitLabel(GetCPISymbol(CPI)); 1042 1043 if (CPE.isMachineConstantPoolEntry()) 1044 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal); 1045 else 1046 EmitGlobalConstant(CPE.Val.ConstVal); 1047 } 1048 } 1049} 1050 1051/// EmitJumpTableInfo - Print assembly representations of the jump tables used 1052/// by the current function to the current output stream. 1053/// 1054void AsmPrinter::EmitJumpTableInfo() { 1055 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 1056 if (MJTI == 0) return; 1057 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return; 1058 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 1059 if (JT.empty()) return; 1060 1061 // Pick the directive to use to print the jump table entries, and switch to 1062 // the appropriate section. 1063 const Function *F = MF->getFunction(); 1064 bool JTInDiffSection = false; 1065 if (// In PIC mode, we need to emit the jump table to the same section as the 1066 // function body itself, otherwise the label differences won't make sense. 1067 // FIXME: Need a better predicate for this: what about custom entries? 1068 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 || 1069 // We should also do if the section name is NULL or function is declared 1070 // in discardable section 1071 // FIXME: this isn't the right predicate, should be based on the MCSection 1072 // for the function. 1073 F->isWeakForLinker()) { 1074 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM)); 1075 } else { 1076 // Otherwise, drop it in the readonly section. 1077 const MCSection *ReadOnlySection = 1078 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly()); 1079 OutStreamer.SwitchSection(ReadOnlySection); 1080 JTInDiffSection = true; 1081 } 1082 1083 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData()))); 1084 1085 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) { 1086 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 1087 1088 // If this jump table was deleted, ignore it. 1089 if (JTBBs.empty()) continue; 1090 1091 // For the EK_LabelDifference32 entry, if the target supports .set, emit a 1092 // .set directive for each unique entry. This reduces the number of 1093 // relocations the assembler will generate for the jump table. 1094 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 && 1095 MAI->hasSetDirective()) { 1096 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets; 1097 const TargetLowering *TLI = TM.getTargetLowering(); 1098 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext); 1099 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) { 1100 const MachineBasicBlock *MBB = JTBBs[ii]; 1101 if (!EmittedSets.insert(MBB)) continue; 1102 1103 // .set LJTSet, LBB32-base 1104 const MCExpr *LHS = 1105 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1106 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()), 1107 MCBinaryExpr::CreateSub(LHS, Base, OutContext)); 1108 } 1109 } 1110 1111 // On some targets (e.g. Darwin) we want to emit two consecutive labels 1112 // before each jump table. The first label is never referenced, but tells 1113 // the assembler and linker the extents of the jump table object. The 1114 // second label is actually referenced by the code. 1115 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0]) 1116 // FIXME: This doesn't have to have any specific name, just any randomly 1117 // named and numbered 'l' label would work. Simplify GetJTISymbol. 1118 OutStreamer.EmitLabel(GetJTISymbol(JTI, true)); 1119 1120 OutStreamer.EmitLabel(GetJTISymbol(JTI)); 1121 1122 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) 1123 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI); 1124 } 1125} 1126 1127/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the 1128/// current stream. 1129void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI, 1130 const MachineBasicBlock *MBB, 1131 unsigned UID) const { 1132 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block"); 1133 const MCExpr *Value = 0; 1134 switch (MJTI->getEntryKind()) { 1135 case MachineJumpTableInfo::EK_Inline: 1136 llvm_unreachable("Cannot emit EK_Inline jump table entry"); 1137 case MachineJumpTableInfo::EK_Custom32: 1138 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID, 1139 OutContext); 1140 break; 1141 case MachineJumpTableInfo::EK_BlockAddress: 1142 // EK_BlockAddress - Each entry is a plain address of block, e.g.: 1143 // .word LBB123 1144 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1145 break; 1146 case MachineJumpTableInfo::EK_GPRel32BlockAddress: { 1147 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded 1148 // with a relocation as gp-relative, e.g.: 1149 // .gprel32 LBB123 1150 MCSymbol *MBBSym = MBB->getSymbol(); 1151 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1152 return; 1153 } 1154 1155 case MachineJumpTableInfo::EK_GPRel64BlockAddress: { 1156 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded 1157 // with a relocation as gp-relative, e.g.: 1158 // .gpdword LBB123 1159 MCSymbol *MBBSym = MBB->getSymbol(); 1160 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1161 return; 1162 } 1163 1164 case MachineJumpTableInfo::EK_LabelDifference32: { 1165 // EK_LabelDifference32 - Each entry is the address of the block minus 1166 // the address of the jump table. This is used for PIC jump tables where 1167 // gprel32 is not supported. e.g.: 1168 // .word LBB123 - LJTI1_2 1169 // If the .set directive is supported, this is emitted as: 1170 // .set L4_5_set_123, LBB123 - LJTI1_2 1171 // .word L4_5_set_123 1172 1173 // If we have emitted set directives for the jump table entries, print 1174 // them rather than the entries themselves. If we're emitting PIC, then 1175 // emit the table entries as differences between two text section labels. 1176 if (MAI->hasSetDirective()) { 1177 // If we used .set, reference the .set's symbol. 1178 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()), 1179 OutContext); 1180 break; 1181 } 1182 // Otherwise, use the difference as the jump table entry. 1183 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1184 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext); 1185 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext); 1186 break; 1187 } 1188 } 1189 1190 assert(Value && "Unknown entry kind!"); 1191 1192 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData()); 1193 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0); 1194} 1195 1196 1197/// EmitSpecialLLVMGlobal - Check to see if the specified global is a 1198/// special global used by LLVM. If so, emit it and return true, otherwise 1199/// do nothing and return false. 1200bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) { 1201 if (GV->getName() == "llvm.used") { 1202 if (MAI->hasNoDeadStrip()) // No need to emit this at all. 1203 EmitLLVMUsedList(GV->getInitializer()); 1204 return true; 1205 } 1206 1207 // Ignore debug and non-emitted data. This handles llvm.compiler.used. 1208 if (GV->getSection() == "llvm.metadata" || 1209 GV->hasAvailableExternallyLinkage()) 1210 return true; 1211 1212 if (!GV->hasAppendingLinkage()) return false; 1213 1214 assert(GV->hasInitializer() && "Not a special LLVM global!"); 1215 1216 if (GV->getName() == "llvm.global_ctors") { 1217 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true); 1218 1219 if (TM.getRelocationModel() == Reloc::Static && 1220 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1221 StringRef Sym(".constructors_used"); 1222 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1223 MCSA_Reference); 1224 } 1225 return true; 1226 } 1227 1228 if (GV->getName() == "llvm.global_dtors") { 1229 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false); 1230 1231 if (TM.getRelocationModel() == Reloc::Static && 1232 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1233 StringRef Sym(".destructors_used"); 1234 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1235 MCSA_Reference); 1236 } 1237 return true; 1238 } 1239 1240 return false; 1241} 1242 1243/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each 1244/// global in the specified llvm.used list for which emitUsedDirectiveFor 1245/// is true, as being used with this directive. 1246void AsmPrinter::EmitLLVMUsedList(const Constant *List) { 1247 // Should be an array of 'i8*'. 1248 const ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1249 if (InitList == 0) return; 1250 1251 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1252 const GlobalValue *GV = 1253 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts()); 1254 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang)) 1255 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip); 1256 } 1257} 1258 1259typedef std::pair<unsigned, Constant*> Structor; 1260 1261static bool priority_order(const Structor& lhs, const Structor& rhs) { 1262 return lhs.first < rhs.first; 1263} 1264 1265/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init 1266/// priority. 1267void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) { 1268 // Should be an array of '{ int, void ()* }' structs. The first value is the 1269 // init priority. 1270 if (!isa<ConstantArray>(List)) return; 1271 1272 // Sanity check the structors list. 1273 const ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1274 if (!InitList) return; // Not an array! 1275 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType()); 1276 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs! 1277 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) || 1278 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr). 1279 1280 // Gather the structors in a form that's convenient for sorting by priority. 1281 SmallVector<Structor, 8> Structors; 1282 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1283 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i)); 1284 if (!CS) continue; // Malformed. 1285 if (CS->getOperand(1)->isNullValue()) 1286 break; // Found a null terminator, skip the rest. 1287 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0)); 1288 if (!Priority) continue; // Malformed. 1289 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535), 1290 CS->getOperand(1))); 1291 } 1292 1293 // Emit the function pointers in the target-specific order 1294 const TargetData *TD = TM.getTargetData(); 1295 unsigned Align = Log2_32(TD->getPointerPrefAlignment()); 1296 std::stable_sort(Structors.begin(), Structors.end(), priority_order); 1297 for (unsigned i = 0, e = Structors.size(); i != e; ++i) { 1298 const MCSection *OutputSection = 1299 (isCtor ? 1300 getObjFileLowering().getStaticCtorSection(Structors[i].first) : 1301 getObjFileLowering().getStaticDtorSection(Structors[i].first)); 1302 OutStreamer.SwitchSection(OutputSection); 1303 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection()) 1304 EmitAlignment(Align); 1305 EmitXXStructor(Structors[i].second); 1306 } 1307} 1308 1309//===--------------------------------------------------------------------===// 1310// Emission and print routines 1311// 1312 1313/// EmitInt8 - Emit a byte directive and value. 1314/// 1315void AsmPrinter::EmitInt8(int Value) const { 1316 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/); 1317} 1318 1319/// EmitInt16 - Emit a short directive and value. 1320/// 1321void AsmPrinter::EmitInt16(int Value) const { 1322 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/); 1323} 1324 1325/// EmitInt32 - Emit a long directive and value. 1326/// 1327void AsmPrinter::EmitInt32(int Value) const { 1328 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/); 1329} 1330 1331/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size 1332/// in bytes of the directive is specified by Size and Hi/Lo specify the 1333/// labels. This implicitly uses .set if it is available. 1334void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, 1335 unsigned Size) const { 1336 // Get the Hi-Lo expression. 1337 const MCExpr *Diff = 1338 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext), 1339 MCSymbolRefExpr::Create(Lo, OutContext), 1340 OutContext); 1341 1342 if (!MAI->hasSetDirective()) { 1343 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/); 1344 return; 1345 } 1346 1347 // Otherwise, emit with .set (aka assignment). 1348 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1349 OutStreamer.EmitAssignment(SetLabel, Diff); 1350 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/); 1351} 1352 1353/// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo" 1354/// where the size in bytes of the directive is specified by Size and Hi/Lo 1355/// specify the labels. This implicitly uses .set if it is available. 1356void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset, 1357 const MCSymbol *Lo, unsigned Size) 1358 const { 1359 1360 // Emit Hi+Offset - Lo 1361 // Get the Hi+Offset expression. 1362 const MCExpr *Plus = 1363 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext), 1364 MCConstantExpr::Create(Offset, OutContext), 1365 OutContext); 1366 1367 // Get the Hi+Offset-Lo expression. 1368 const MCExpr *Diff = 1369 MCBinaryExpr::CreateSub(Plus, 1370 MCSymbolRefExpr::Create(Lo, OutContext), 1371 OutContext); 1372 1373 if (!MAI->hasSetDirective()) 1374 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/); 1375 else { 1376 // Otherwise, emit with .set (aka assignment). 1377 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1378 OutStreamer.EmitAssignment(SetLabel, Diff); 1379 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/); 1380 } 1381} 1382 1383/// EmitLabelPlusOffset - Emit something like ".long Label+Offset" 1384/// where the size in bytes of the directive is specified by Size and Label 1385/// specifies the label. This implicitly uses .set if it is available. 1386void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset, 1387 unsigned Size) 1388 const { 1389 1390 // Emit Label+Offset (or just Label if Offset is zero) 1391 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext); 1392 if (Offset) 1393 Expr = MCBinaryExpr::CreateAdd(Expr, 1394 MCConstantExpr::Create(Offset, OutContext), 1395 OutContext); 1396 1397 OutStreamer.EmitValue(Expr, Size, 0/*AddrSpace*/); 1398} 1399 1400 1401//===----------------------------------------------------------------------===// 1402 1403// EmitAlignment - Emit an alignment directive to the specified power of 1404// two boundary. For example, if you pass in 3 here, you will get an 8 1405// byte alignment. If a global value is specified, and if that global has 1406// an explicit alignment requested, it will override the alignment request 1407// if required for correctness. 1408// 1409void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const { 1410 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getTargetData(), NumBits); 1411 1412 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment. 1413 1414 if (getCurrentSection()->getKind().isText()) 1415 OutStreamer.EmitCodeAlignment(1 << NumBits); 1416 else 1417 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0); 1418} 1419 1420//===----------------------------------------------------------------------===// 1421// Constant emission. 1422//===----------------------------------------------------------------------===// 1423 1424/// LowerConstant - Lower the specified LLVM Constant to an MCExpr. 1425/// 1426static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) { 1427 MCContext &Ctx = AP.OutContext; 1428 1429 if (CV->isNullValue() || isa<UndefValue>(CV)) 1430 return MCConstantExpr::Create(0, Ctx); 1431 1432 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) 1433 return MCConstantExpr::Create(CI->getZExtValue(), Ctx); 1434 1435 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 1436 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx); 1437 1438 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV)) 1439 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx); 1440 1441 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV); 1442 if (CE == 0) { 1443 llvm_unreachable("Unknown constant value to lower!"); 1444 } 1445 1446 switch (CE->getOpcode()) { 1447 default: 1448 // If the code isn't optimized, there may be outstanding folding 1449 // opportunities. Attempt to fold the expression using TargetData as a 1450 // last resort before giving up. 1451 if (Constant *C = 1452 ConstantFoldConstantExpression(CE, AP.TM.getTargetData())) 1453 if (C != CE) 1454 return LowerConstant(C, AP); 1455 1456 // Otherwise report the problem to the user. 1457 { 1458 std::string S; 1459 raw_string_ostream OS(S); 1460 OS << "Unsupported expression in static initializer: "; 1461 WriteAsOperand(OS, CE, /*PrintType=*/false, 1462 !AP.MF ? 0 : AP.MF->getFunction()->getParent()); 1463 report_fatal_error(OS.str()); 1464 } 1465 case Instruction::GetElementPtr: { 1466 const TargetData &TD = *AP.TM.getTargetData(); 1467 // Generate a symbolic expression for the byte address 1468 const Constant *PtrVal = CE->getOperand(0); 1469 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end()); 1470 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), IdxVec); 1471 1472 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP); 1473 if (Offset == 0) 1474 return Base; 1475 1476 // Truncate/sext the offset to the pointer size. 1477 unsigned Width = TD.getPointerSizeInBits(); 1478 if (Width < 64) 1479 Offset = SignExtend64(Offset, Width); 1480 1481 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx), 1482 Ctx); 1483 } 1484 1485 case Instruction::Trunc: 1486 // We emit the value and depend on the assembler to truncate the generated 1487 // expression properly. This is important for differences between 1488 // blockaddress labels. Since the two labels are in the same function, it 1489 // is reasonable to treat their delta as a 32-bit value. 1490 // FALL THROUGH. 1491 case Instruction::BitCast: 1492 return LowerConstant(CE->getOperand(0), AP); 1493 1494 case Instruction::IntToPtr: { 1495 const TargetData &TD = *AP.TM.getTargetData(); 1496 // Handle casts to pointers by changing them into casts to the appropriate 1497 // integer type. This promotes constant folding and simplifies this code. 1498 Constant *Op = CE->getOperand(0); 1499 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()), 1500 false/*ZExt*/); 1501 return LowerConstant(Op, AP); 1502 } 1503 1504 case Instruction::PtrToInt: { 1505 const TargetData &TD = *AP.TM.getTargetData(); 1506 // Support only foldable casts to/from pointers that can be eliminated by 1507 // changing the pointer to the appropriately sized integer type. 1508 Constant *Op = CE->getOperand(0); 1509 Type *Ty = CE->getType(); 1510 1511 const MCExpr *OpExpr = LowerConstant(Op, AP); 1512 1513 // We can emit the pointer value into this slot if the slot is an 1514 // integer slot equal to the size of the pointer. 1515 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType())) 1516 return OpExpr; 1517 1518 // Otherwise the pointer is smaller than the resultant integer, mask off 1519 // the high bits so we are sure to get a proper truncation if the input is 1520 // a constant expr. 1521 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType()); 1522 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx); 1523 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx); 1524 } 1525 1526 // The MC library also has a right-shift operator, but it isn't consistently 1527 // signed or unsigned between different targets. 1528 case Instruction::Add: 1529 case Instruction::Sub: 1530 case Instruction::Mul: 1531 case Instruction::SDiv: 1532 case Instruction::SRem: 1533 case Instruction::Shl: 1534 case Instruction::And: 1535 case Instruction::Or: 1536 case Instruction::Xor: { 1537 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP); 1538 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP); 1539 switch (CE->getOpcode()) { 1540 default: llvm_unreachable("Unknown binary operator constant cast expr"); 1541 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx); 1542 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx); 1543 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx); 1544 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx); 1545 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx); 1546 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx); 1547 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx); 1548 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx); 1549 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx); 1550 } 1551 } 1552 } 1553} 1554 1555static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace, 1556 AsmPrinter &AP); 1557 1558/// isRepeatedByteSequence - Determine whether the given value is 1559/// composed of a repeated sequence of identical bytes and return the 1560/// byte value. If it is not a repeated sequence, return -1. 1561static int isRepeatedByteSequence(const ConstantDataSequential *V) { 1562 StringRef Data = V->getRawDataValues(); 1563 assert(!Data.empty() && "Empty aggregates should be CAZ node"); 1564 char C = Data[0]; 1565 for (unsigned i = 1, e = Data.size(); i != e; ++i) 1566 if (Data[i] != C) return -1; 1567 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1. 1568} 1569 1570 1571/// isRepeatedByteSequence - Determine whether the given value is 1572/// composed of a repeated sequence of identical bytes and return the 1573/// byte value. If it is not a repeated sequence, return -1. 1574static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) { 1575 1576 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { 1577 if (CI->getBitWidth() > 64) return -1; 1578 1579 uint64_t Size = TM.getTargetData()->getTypeAllocSize(V->getType()); 1580 uint64_t Value = CI->getZExtValue(); 1581 1582 // Make sure the constant is at least 8 bits long and has a power 1583 // of 2 bit width. This guarantees the constant bit width is 1584 // always a multiple of 8 bits, avoiding issues with padding out 1585 // to Size and other such corner cases. 1586 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1; 1587 1588 uint8_t Byte = static_cast<uint8_t>(Value); 1589 1590 for (unsigned i = 1; i < Size; ++i) { 1591 Value >>= 8; 1592 if (static_cast<uint8_t>(Value) != Byte) return -1; 1593 } 1594 return Byte; 1595 } 1596 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) { 1597 // Make sure all array elements are sequences of the same repeated 1598 // byte. 1599 assert(CA->getNumOperands() != 0 && "Should be a CAZ"); 1600 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM); 1601 if (Byte == -1) return -1; 1602 1603 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) { 1604 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM); 1605 if (ThisByte == -1) return -1; 1606 if (Byte != ThisByte) return -1; 1607 } 1608 return Byte; 1609 } 1610 1611 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V)) 1612 return isRepeatedByteSequence(CDS); 1613 1614 return -1; 1615} 1616 1617static void EmitGlobalConstantDataSequential(const ConstantDataSequential *CDS, 1618 unsigned AddrSpace,AsmPrinter &AP){ 1619 1620 // See if we can aggregate this into a .fill, if so, emit it as such. 1621 int Value = isRepeatedByteSequence(CDS, AP.TM); 1622 if (Value != -1) { 1623 uint64_t Bytes = AP.TM.getTargetData()->getTypeAllocSize(CDS->getType()); 1624 // Don't emit a 1-byte object as a .fill. 1625 if (Bytes > 1) 1626 return AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace); 1627 } 1628 1629 // If this can be emitted with .ascii/.asciz, emit it as such. 1630 if (CDS->isString()) 1631 return AP.OutStreamer.EmitBytes(CDS->getAsString(), AddrSpace); 1632 1633 // Otherwise, emit the values in successive locations. 1634 unsigned ElementByteSize = CDS->getElementByteSize(); 1635 if (isa<IntegerType>(CDS->getElementType())) { 1636 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1637 if (AP.isVerbose()) 1638 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n", 1639 CDS->getElementAsInteger(i)); 1640 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i), 1641 ElementByteSize, AddrSpace); 1642 } 1643 } else if (ElementByteSize == 4) { 1644 // FP Constants are printed as integer constants to avoid losing 1645 // precision. 1646 assert(CDS->getElementType()->isFloatTy()); 1647 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1648 union { 1649 float F; 1650 uint32_t I; 1651 }; 1652 1653 F = CDS->getElementAsFloat(i); 1654 if (AP.isVerbose()) 1655 AP.OutStreamer.GetCommentOS() << "float " << F << '\n'; 1656 AP.OutStreamer.EmitIntValue(I, 4, AddrSpace); 1657 } 1658 } else { 1659 assert(CDS->getElementType()->isDoubleTy()); 1660 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { 1661 union { 1662 double F; 1663 uint64_t I; 1664 }; 1665 1666 F = CDS->getElementAsDouble(i); 1667 if (AP.isVerbose()) 1668 AP.OutStreamer.GetCommentOS() << "double " << F << '\n'; 1669 AP.OutStreamer.EmitIntValue(I, 8, AddrSpace); 1670 } 1671 } 1672 1673 const TargetData &TD = *AP.TM.getTargetData(); 1674 unsigned Size = TD.getTypeAllocSize(CDS->getType()); 1675 unsigned EmittedSize = TD.getTypeAllocSize(CDS->getType()->getElementType()) * 1676 CDS->getNumElements(); 1677 if (unsigned Padding = Size - EmittedSize) 1678 AP.OutStreamer.EmitZeros(Padding, AddrSpace); 1679 1680} 1681 1682static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace, 1683 AsmPrinter &AP) { 1684 // See if we can aggregate some values. Make sure it can be 1685 // represented as a series of bytes of the constant value. 1686 int Value = isRepeatedByteSequence(CA, AP.TM); 1687 1688 if (Value != -1) { 1689 uint64_t Bytes = AP.TM.getTargetData()->getTypeAllocSize(CA->getType()); 1690 AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace); 1691 } 1692 else { 1693 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1694 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP); 1695 } 1696} 1697 1698static void EmitGlobalConstantVector(const ConstantVector *CV, 1699 unsigned AddrSpace, AsmPrinter &AP) { 1700 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i) 1701 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP); 1702 1703 const TargetData &TD = *AP.TM.getTargetData(); 1704 unsigned Size = TD.getTypeAllocSize(CV->getType()); 1705 unsigned EmittedSize = TD.getTypeAllocSize(CV->getType()->getElementType()) * 1706 CV->getType()->getNumElements(); 1707 if (unsigned Padding = Size - EmittedSize) 1708 AP.OutStreamer.EmitZeros(Padding, AddrSpace); 1709} 1710 1711static void EmitGlobalConstantStruct(const ConstantStruct *CS, 1712 unsigned AddrSpace, AsmPrinter &AP) { 1713 // Print the fields in successive locations. Pad to align if needed! 1714 const TargetData *TD = AP.TM.getTargetData(); 1715 unsigned Size = TD->getTypeAllocSize(CS->getType()); 1716 const StructLayout *Layout = TD->getStructLayout(CS->getType()); 1717 uint64_t SizeSoFar = 0; 1718 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 1719 const Constant *Field = CS->getOperand(i); 1720 1721 // Check if padding is needed and insert one or more 0s. 1722 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType()); 1723 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1)) 1724 - Layout->getElementOffset(i)) - FieldSize; 1725 SizeSoFar += FieldSize + PadSize; 1726 1727 // Now print the actual field value. 1728 EmitGlobalConstantImpl(Field, AddrSpace, AP); 1729 1730 // Insert padding - this may include padding to increase the size of the 1731 // current field up to the ABI size (if the struct is not packed) as well 1732 // as padding to ensure that the next field starts at the right offset. 1733 AP.OutStreamer.EmitZeros(PadSize, AddrSpace); 1734 } 1735 assert(SizeSoFar == Layout->getSizeInBytes() && 1736 "Layout of constant struct may be incorrect!"); 1737} 1738 1739static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace, 1740 AsmPrinter &AP) { 1741 if (CFP->getType()->isHalfTy()) { 1742 if (AP.isVerbose()) { 1743 SmallString<10> Str; 1744 CFP->getValueAPF().toString(Str); 1745 AP.OutStreamer.GetCommentOS() << "half " << Str << '\n'; 1746 } 1747 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1748 AP.OutStreamer.EmitIntValue(Val, 2, AddrSpace); 1749 return; 1750 } 1751 1752 if (CFP->getType()->isFloatTy()) { 1753 if (AP.isVerbose()) { 1754 float Val = CFP->getValueAPF().convertToFloat(); 1755 uint64_t IntVal = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1756 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n' 1757 << " (" << format("0x%x", IntVal) << ")\n"; 1758 } 1759 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1760 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace); 1761 return; 1762 } 1763 1764 // FP Constants are printed as integer constants to avoid losing 1765 // precision. 1766 if (CFP->getType()->isDoubleTy()) { 1767 if (AP.isVerbose()) { 1768 double Val = CFP->getValueAPF().convertToDouble(); 1769 uint64_t IntVal = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1770 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n' 1771 << " (" << format("0x%lx", IntVal) << ")\n"; 1772 } 1773 1774 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1775 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1776 return; 1777 } 1778 1779 if (CFP->getType()->isX86_FP80Ty()) { 1780 // all long double variants are printed as hex 1781 // API needed to prevent premature destruction 1782 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1783 const uint64_t *p = API.getRawData(); 1784 if (AP.isVerbose()) { 1785 // Convert to double so we can print the approximate val as a comment. 1786 APFloat DoubleVal = CFP->getValueAPF(); 1787 bool ignored; 1788 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 1789 &ignored); 1790 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= " 1791 << DoubleVal.convertToDouble() << '\n'; 1792 } 1793 1794 if (AP.TM.getTargetData()->isBigEndian()) { 1795 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1796 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1797 } else { 1798 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1799 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1800 } 1801 1802 // Emit the tail padding for the long double. 1803 const TargetData &TD = *AP.TM.getTargetData(); 1804 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) - 1805 TD.getTypeStoreSize(CFP->getType()), AddrSpace); 1806 return; 1807 } 1808 1809 assert(CFP->getType()->isPPC_FP128Ty() && 1810 "Floating point constant type not handled"); 1811 // All long double variants are printed as hex 1812 // API needed to prevent premature destruction. 1813 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1814 const uint64_t *p = API.getRawData(); 1815 if (AP.TM.getTargetData()->isBigEndian()) { 1816 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1817 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1818 } else { 1819 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1820 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1821 } 1822} 1823 1824static void EmitGlobalConstantLargeInt(const ConstantInt *CI, 1825 unsigned AddrSpace, AsmPrinter &AP) { 1826 const TargetData *TD = AP.TM.getTargetData(); 1827 unsigned BitWidth = CI->getBitWidth(); 1828 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits"); 1829 1830 // We don't expect assemblers to support integer data directives 1831 // for more than 64 bits, so we emit the data in at most 64-bit 1832 // quantities at a time. 1833 const uint64_t *RawData = CI->getValue().getRawData(); 1834 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) { 1835 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i]; 1836 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1837 } 1838} 1839 1840static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace, 1841 AsmPrinter &AP) { 1842 const TargetData *TD = AP.TM.getTargetData(); 1843 uint64_t Size = TD->getTypeAllocSize(CV->getType()); 1844 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) 1845 return AP.OutStreamer.EmitZeros(Size, AddrSpace); 1846 1847 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { 1848 switch (Size) { 1849 case 1: 1850 case 2: 1851 case 4: 1852 case 8: 1853 if (AP.isVerbose()) 1854 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n", 1855 CI->getZExtValue()); 1856 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace); 1857 return; 1858 default: 1859 EmitGlobalConstantLargeInt(CI, AddrSpace, AP); 1860 return; 1861 } 1862 } 1863 1864 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) 1865 return EmitGlobalConstantFP(CFP, AddrSpace, AP); 1866 1867 if (isa<ConstantPointerNull>(CV)) { 1868 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace); 1869 return; 1870 } 1871 1872 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV)) 1873 return EmitGlobalConstantDataSequential(CDS, AddrSpace, AP); 1874 1875 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) 1876 return EmitGlobalConstantArray(CVA, AddrSpace, AP); 1877 1878 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) 1879 return EmitGlobalConstantStruct(CVS, AddrSpace, AP); 1880 1881 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) { 1882 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of 1883 // vectors). 1884 if (CE->getOpcode() == Instruction::BitCast) 1885 return EmitGlobalConstantImpl(CE->getOperand(0), AddrSpace, AP); 1886 1887 if (Size > 8) { 1888 // If the constant expression's size is greater than 64-bits, then we have 1889 // to emit the value in chunks. Try to constant fold the value and emit it 1890 // that way. 1891 Constant *New = ConstantFoldConstantExpression(CE, TD); 1892 if (New && New != CE) 1893 return EmitGlobalConstantImpl(New, AddrSpace, AP); 1894 } 1895 } 1896 1897 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV)) 1898 return EmitGlobalConstantVector(V, AddrSpace, AP); 1899 1900 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it 1901 // thread the streamer with EmitValue. 1902 AP.OutStreamer.EmitValue(LowerConstant(CV, AP), Size, AddrSpace); 1903} 1904 1905/// EmitGlobalConstant - Print a general LLVM constant to the .s file. 1906void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) { 1907 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1908 if (Size) 1909 EmitGlobalConstantImpl(CV, AddrSpace, *this); 1910 else if (MAI->hasSubsectionsViaSymbols()) { 1911 // If the global has zero size, emit a single byte so that two labels don't 1912 // look like they are at the same location. 1913 OutStreamer.EmitIntValue(0, 1, AddrSpace); 1914 } 1915} 1916 1917void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 1918 // Target doesn't support this yet! 1919 llvm_unreachable("Target does not support EmitMachineConstantPoolValue"); 1920} 1921 1922void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const { 1923 if (Offset > 0) 1924 OS << '+' << Offset; 1925 else if (Offset < 0) 1926 OS << Offset; 1927} 1928 1929//===----------------------------------------------------------------------===// 1930// Symbol Lowering Routines. 1931//===----------------------------------------------------------------------===// 1932 1933/// GetTempSymbol - Return the MCSymbol corresponding to the assembler 1934/// temporary label with the specified stem and unique ID. 1935MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const { 1936 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + 1937 Name + Twine(ID)); 1938} 1939 1940/// GetTempSymbol - Return an assembler temporary label with the specified 1941/// stem. 1942MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const { 1943 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+ 1944 Name); 1945} 1946 1947 1948MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const { 1949 return MMI->getAddrLabelSymbol(BA->getBasicBlock()); 1950} 1951 1952MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const { 1953 return MMI->getAddrLabelSymbol(BB); 1954} 1955 1956/// GetCPISymbol - Return the symbol for the specified constant pool entry. 1957MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const { 1958 return OutContext.GetOrCreateSymbol 1959 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber()) 1960 + "_" + Twine(CPID)); 1961} 1962 1963/// GetJTISymbol - Return the symbol for the specified jump table entry. 1964MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const { 1965 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate); 1966} 1967 1968/// GetJTSetSymbol - Return the symbol for the specified jump table .set 1969/// FIXME: privatize to AsmPrinter. 1970MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const { 1971 return OutContext.GetOrCreateSymbol 1972 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" + 1973 Twine(UID) + "_set_" + Twine(MBBID)); 1974} 1975 1976/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with 1977/// global value name as its base, with the specified suffix, and where the 1978/// symbol is forced to have private linkage if ForcePrivate is true. 1979MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV, 1980 StringRef Suffix, 1981 bool ForcePrivate) const { 1982 SmallString<60> NameStr; 1983 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate); 1984 NameStr.append(Suffix.begin(), Suffix.end()); 1985 return OutContext.GetOrCreateSymbol(NameStr.str()); 1986} 1987 1988/// GetExternalSymbolSymbol - Return the MCSymbol for the specified 1989/// ExternalSymbol. 1990MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const { 1991 SmallString<60> NameStr; 1992 Mang->getNameWithPrefix(NameStr, Sym); 1993 return OutContext.GetOrCreateSymbol(NameStr.str()); 1994} 1995 1996 1997 1998/// PrintParentLoopComment - Print comments about parent loops of this one. 1999static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop, 2000 unsigned FunctionNumber) { 2001 if (Loop == 0) return; 2002 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber); 2003 OS.indent(Loop->getLoopDepth()*2) 2004 << "Parent Loop BB" << FunctionNumber << "_" 2005 << Loop->getHeader()->getNumber() 2006 << " Depth=" << Loop->getLoopDepth() << '\n'; 2007} 2008 2009 2010/// PrintChildLoopComment - Print comments about child loops within 2011/// the loop for this basic block, with nesting. 2012static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop, 2013 unsigned FunctionNumber) { 2014 // Add child loop information 2015 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){ 2016 OS.indent((*CL)->getLoopDepth()*2) 2017 << "Child Loop BB" << FunctionNumber << "_" 2018 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth() 2019 << '\n'; 2020 PrintChildLoopComment(OS, *CL, FunctionNumber); 2021 } 2022} 2023 2024/// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks. 2025static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB, 2026 const MachineLoopInfo *LI, 2027 const AsmPrinter &AP) { 2028 // Add loop depth information 2029 const MachineLoop *Loop = LI->getLoopFor(&MBB); 2030 if (Loop == 0) return; 2031 2032 MachineBasicBlock *Header = Loop->getHeader(); 2033 assert(Header && "No header for loop"); 2034 2035 // If this block is not a loop header, just print out what is the loop header 2036 // and return. 2037 if (Header != &MBB) { 2038 AP.OutStreamer.AddComment(" in Loop: Header=BB" + 2039 Twine(AP.getFunctionNumber())+"_" + 2040 Twine(Loop->getHeader()->getNumber())+ 2041 " Depth="+Twine(Loop->getLoopDepth())); 2042 return; 2043 } 2044 2045 // Otherwise, it is a loop header. Print out information about child and 2046 // parent loops. 2047 raw_ostream &OS = AP.OutStreamer.GetCommentOS(); 2048 2049 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 2050 2051 OS << "=>"; 2052 OS.indent(Loop->getLoopDepth()*2-2); 2053 2054 OS << "This "; 2055 if (Loop->empty()) 2056 OS << "Inner "; 2057 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n'; 2058 2059 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber()); 2060} 2061 2062 2063/// EmitBasicBlockStart - This method prints the label for the specified 2064/// MachineBasicBlock, an alignment (if present) and a comment describing 2065/// it if appropriate. 2066void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const { 2067 // Emit an alignment directive for this block, if needed. 2068 if (unsigned Align = MBB->getAlignment()) 2069 EmitAlignment(Align); 2070 2071 // If the block has its address taken, emit any labels that were used to 2072 // reference the block. It is possible that there is more than one label 2073 // here, because multiple LLVM BB's may have been RAUW'd to this block after 2074 // the references were generated. 2075 if (MBB->hasAddressTaken()) { 2076 const BasicBlock *BB = MBB->getBasicBlock(); 2077 if (isVerbose()) 2078 OutStreamer.AddComment("Block address taken"); 2079 2080 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB); 2081 2082 for (unsigned i = 0, e = Syms.size(); i != e; ++i) 2083 OutStreamer.EmitLabel(Syms[i]); 2084 } 2085 2086 // Print some verbose block comments. 2087 if (isVerbose()) { 2088 if (const BasicBlock *BB = MBB->getBasicBlock()) 2089 if (BB->hasName()) 2090 OutStreamer.AddComment("%" + BB->getName()); 2091 EmitBasicBlockLoopComments(*MBB, LI, *this); 2092 } 2093 2094 // Print the main label for the block. 2095 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) { 2096 if (isVerbose() && OutStreamer.hasRawTextSupport()) { 2097 // NOTE: Want this comment at start of line, don't emit with AddComment. 2098 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" + 2099 Twine(MBB->getNumber()) + ":"); 2100 } 2101 } else { 2102 OutStreamer.EmitLabel(MBB->getSymbol()); 2103 } 2104} 2105 2106void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility, 2107 bool IsDefinition) const { 2108 MCSymbolAttr Attr = MCSA_Invalid; 2109 2110 switch (Visibility) { 2111 default: break; 2112 case GlobalValue::HiddenVisibility: 2113 if (IsDefinition) 2114 Attr = MAI->getHiddenVisibilityAttr(); 2115 else 2116 Attr = MAI->getHiddenDeclarationVisibilityAttr(); 2117 break; 2118 case GlobalValue::ProtectedVisibility: 2119 Attr = MAI->getProtectedVisibilityAttr(); 2120 break; 2121 } 2122 2123 if (Attr != MCSA_Invalid) 2124 OutStreamer.EmitSymbolAttribute(Sym, Attr); 2125} 2126 2127/// isBlockOnlyReachableByFallthough - Return true if the basic block has 2128/// exactly one predecessor and the control transfer mechanism between 2129/// the predecessor and this block is a fall-through. 2130bool AsmPrinter:: 2131isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const { 2132 // If this is a landing pad, it isn't a fall through. If it has no preds, 2133 // then nothing falls through to it. 2134 if (MBB->isLandingPad() || MBB->pred_empty()) 2135 return false; 2136 2137 // If there isn't exactly one predecessor, it can't be a fall through. 2138 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI; 2139 ++PI2; 2140 if (PI2 != MBB->pred_end()) 2141 return false; 2142 2143 // The predecessor has to be immediately before this block. 2144 MachineBasicBlock *Pred = *PI; 2145 2146 if (!Pred->isLayoutSuccessor(MBB)) 2147 return false; 2148 2149 // If the block is completely empty, then it definitely does fall through. 2150 if (Pred->empty()) 2151 return true; 2152 2153 // Check the terminators in the previous blocks 2154 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(), 2155 IE = Pred->end(); II != IE; ++II) { 2156 MachineInstr &MI = *II; 2157 2158 // If it is not a simple branch, we are in a table somewhere. 2159 if (!MI.isBranch() || MI.isIndirectBranch()) 2160 return false; 2161 2162 // If we are the operands of one of the branches, this is not 2163 // a fall through. 2164 for (MachineInstr::mop_iterator OI = MI.operands_begin(), 2165 OE = MI.operands_end(); OI != OE; ++OI) { 2166 const MachineOperand& OP = *OI; 2167 if (OP.isJTI()) 2168 return false; 2169 if (OP.isMBB() && OP.getMBB() == MBB) 2170 return false; 2171 } 2172 } 2173 2174 return true; 2175} 2176 2177 2178 2179GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) { 2180 if (!S->usesMetadata()) 2181 return 0; 2182 2183 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 2184 gcp_map_type::iterator GCPI = GCMap.find(S); 2185 if (GCPI != GCMap.end()) 2186 return GCPI->second; 2187 2188 const char *Name = S->getName().c_str(); 2189 2190 for (GCMetadataPrinterRegistry::iterator 2191 I = GCMetadataPrinterRegistry::begin(), 2192 E = GCMetadataPrinterRegistry::end(); I != E; ++I) 2193 if (strcmp(Name, I->getName()) == 0) { 2194 GCMetadataPrinter *GMP = I->instantiate(); 2195 GMP->S = S; 2196 GCMap.insert(std::make_pair(S, GMP)); 2197 return GMP; 2198 } 2199 2200 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name)); 2201} 2202