AsmPrinter.cpp revision d652b1368b1e381382951f450e5eeca870d91dd6
1//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements the AsmPrinter class. 11// 12//===----------------------------------------------------------------------===// 13 14#define DEBUG_TYPE "asm-printer" 15#include "llvm/CodeGen/AsmPrinter.h" 16#include "DwarfDebug.h" 17#include "DwarfException.h" 18#include "llvm/Module.h" 19#include "llvm/CodeGen/GCMetadataPrinter.h" 20#include "llvm/CodeGen/MachineConstantPool.h" 21#include "llvm/CodeGen/MachineFrameInfo.h" 22#include "llvm/CodeGen/MachineFunction.h" 23#include "llvm/CodeGen/MachineJumpTableInfo.h" 24#include "llvm/CodeGen/MachineLoopInfo.h" 25#include "llvm/CodeGen/MachineModuleInfo.h" 26#include "llvm/Analysis/ConstantFolding.h" 27#include "llvm/Analysis/DebugInfo.h" 28#include "llvm/MC/MCAsmInfo.h" 29#include "llvm/MC/MCContext.h" 30#include "llvm/MC/MCExpr.h" 31#include "llvm/MC/MCInst.h" 32#include "llvm/MC/MCSection.h" 33#include "llvm/MC/MCStreamer.h" 34#include "llvm/MC/MCSymbol.h" 35#include "llvm/Target/Mangler.h" 36#include "llvm/Target/TargetAsmInfo.h" 37#include "llvm/Target/TargetData.h" 38#include "llvm/Target/TargetInstrInfo.h" 39#include "llvm/Target/TargetLowering.h" 40#include "llvm/Target/TargetLoweringObjectFile.h" 41#include "llvm/Target/TargetOptions.h" 42#include "llvm/Target/TargetRegisterInfo.h" 43#include "llvm/Assembly/Writer.h" 44#include "llvm/ADT/SmallString.h" 45#include "llvm/ADT/Statistic.h" 46#include "llvm/Support/ErrorHandling.h" 47#include "llvm/Support/Format.h" 48#include "llvm/Support/Timer.h" 49using namespace llvm; 50 51static const char *DWARFGroupName = "DWARF Emission"; 52static const char *DbgTimerName = "DWARF Debug Writer"; 53static const char *EHTimerName = "DWARF Exception Writer"; 54 55STATISTIC(EmittedInsts, "Number of machine instrs printed"); 56 57char AsmPrinter::ID = 0; 58 59typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type; 60static gcp_map_type &getGCMap(void *&P) { 61 if (P == 0) 62 P = new gcp_map_type(); 63 return *(gcp_map_type*)P; 64} 65 66 67/// getGVAlignmentLog2 - Return the alignment to use for the specified global 68/// value in log2 form. This rounds up to the preferred alignment if possible 69/// and legal. 70static unsigned getGVAlignmentLog2(const GlobalValue *GV, const TargetData &TD, 71 unsigned InBits = 0) { 72 unsigned NumBits = 0; 73 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV)) 74 NumBits = TD.getPreferredAlignmentLog(GVar); 75 76 // If InBits is specified, round it to it. 77 if (InBits > NumBits) 78 NumBits = InBits; 79 80 // If the GV has a specified alignment, take it into account. 81 if (GV->getAlignment() == 0) 82 return NumBits; 83 84 unsigned GVAlign = Log2_32(GV->getAlignment()); 85 86 // If the GVAlign is larger than NumBits, or if we are required to obey 87 // NumBits because the GV has an assigned section, obey it. 88 if (GVAlign > NumBits || GV->hasSection()) 89 NumBits = GVAlign; 90 return NumBits; 91} 92 93 94 95 96AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer) 97 : MachineFunctionPass(ID), 98 TM(tm), MAI(tm.getMCAsmInfo()), 99 OutContext(Streamer.getContext()), 100 OutStreamer(Streamer), 101 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) { 102 DD = 0; DE = 0; MMI = 0; LI = 0; 103 GCMetadataPrinters = 0; 104 VerboseAsm = Streamer.isVerboseAsm(); 105} 106 107AsmPrinter::~AsmPrinter() { 108 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized"); 109 110 if (GCMetadataPrinters != 0) { 111 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 112 113 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I) 114 delete I->second; 115 delete &GCMap; 116 GCMetadataPrinters = 0; 117 } 118 119 delete &OutStreamer; 120} 121 122/// getFunctionNumber - Return a unique ID for the current function. 123/// 124unsigned AsmPrinter::getFunctionNumber() const { 125 return MF->getFunctionNumber(); 126} 127 128const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const { 129 return TM.getTargetLowering()->getObjFileLowering(); 130} 131 132 133/// getTargetData - Return information about data layout. 134const TargetData &AsmPrinter::getTargetData() const { 135 return *TM.getTargetData(); 136} 137 138/// getCurrentSection() - Return the current section we are emitting to. 139const MCSection *AsmPrinter::getCurrentSection() const { 140 return OutStreamer.getCurrentSection(); 141} 142 143 144 145void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const { 146 AU.setPreservesAll(); 147 MachineFunctionPass::getAnalysisUsage(AU); 148 AU.addRequired<MachineModuleInfo>(); 149 AU.addRequired<GCModuleInfo>(); 150 if (isVerbose()) 151 AU.addRequired<MachineLoopInfo>(); 152} 153 154bool AsmPrinter::doInitialization(Module &M) { 155 MMI = getAnalysisIfAvailable<MachineModuleInfo>(); 156 MMI->AnalyzeModule(M); 157 158 // Initialize TargetLoweringObjectFile. 159 const_cast<TargetLoweringObjectFile&>(getObjFileLowering()) 160 .Initialize(OutContext, TM); 161 162 Mang = new Mangler(OutContext, *TM.getTargetData()); 163 164 // Allow the target to emit any magic that it wants at the start of the file. 165 EmitStartOfAsmFile(M); 166 167 // Very minimal debug info. It is ignored if we emit actual debug info. If we 168 // don't, this at least helps the user find where a global came from. 169 if (MAI->hasSingleParameterDotFile()) { 170 // .file "foo.c" 171 OutStreamer.EmitFileDirective(M.getModuleIdentifier()); 172 } 173 174 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 175 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 176 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I) 177 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I)) 178 MP->beginAssembly(*this); 179 180 // Emit module-level inline asm if it exists. 181 if (!M.getModuleInlineAsm().empty()) { 182 OutStreamer.AddComment("Start of file scope inline assembly"); 183 OutStreamer.AddBlankLine(); 184 EmitInlineAsm(M.getModuleInlineAsm()+"\n"); 185 OutStreamer.AddComment("End of file scope inline assembly"); 186 OutStreamer.AddBlankLine(); 187 } 188 189 if (MAI->doesSupportDebugInformation()) 190 DD = new DwarfDebug(this, &M); 191 192 switch (MAI->getExceptionHandlingType()) { 193 case ExceptionHandling::None: 194 return false; 195 case ExceptionHandling::SjLj: 196 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()); 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. 293 294 // Handle common symbols. 295 if (GVKind.isCommon()) { 296 unsigned Align = 1 << AlignLog; 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, 1 << AlignLog); 311 return; 312 } 313 314 if (MAI->hasLCOMMDirective()) { 315 // .lcomm _foo, 42 316 OutStreamer.EmitLocalCommonSymbol(GVSym, Size); 317 return; 318 } 319 320 unsigned Align = 1 << AlignLog; 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 { 579 assert(MI->getOperand(0).isReg() && "Unknown operand type"); 580 if (MI->getOperand(0).getReg() == 0) { 581 // Suppress offset, it is not meaningful here. 582 OS << "undef"; 583 // NOTE: Want this comment at start of line, don't emit with AddComment. 584 AP.OutStreamer.EmitRawText(OS.str()); 585 return true; 586 } 587 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg()); 588 } 589 590 OS << '+' << MI->getOperand(1).getImm(); 591 // NOTE: Want this comment at start of line, don't emit with AddComment. 592 AP.OutStreamer.EmitRawText(OS.str()); 593 return true; 594} 595 596AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() { 597 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI && 598 MF->getFunction()->needsUnwindTableEntry()) 599 return CFI_M_EH; 600 601 if (MMI->hasDebugInfo()) 602 return CFI_M_Debug; 603 604 return CFI_M_None; 605} 606 607void AsmPrinter::emitPrologLabel(const MachineInstr &MI) { 608 MCSymbol *Label = MI.getOperand(0).getMCSymbol(); 609 610 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI) 611 return; 612 613 if (needsCFIMoves() == CFI_M_None) 614 return; 615 616 MachineModuleInfo &MMI = MF->getMMI(); 617 std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 618 bool FoundOne = false; 619 (void)FoundOne; 620 for (std::vector<MachineMove>::iterator I = Moves.begin(), 621 E = Moves.end(); I != E; ++I) { 622 if (I->getLabel() == Label) { 623 EmitCFIFrameMove(*I); 624 FoundOne = true; 625 } 626 } 627 assert(FoundOne); 628} 629 630/// EmitFunctionBody - This method emits the body and trailer for a 631/// function. 632void AsmPrinter::EmitFunctionBody() { 633 // Emit target-specific gunk before the function body. 634 EmitFunctionBodyStart(); 635 636 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo(); 637 638 // Print out code for the function. 639 bool HasAnyRealCode = false; 640 const MachineInstr *LastMI = 0; 641 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 642 I != E; ++I) { 643 // Print a label for the basic block. 644 EmitBasicBlockStart(I); 645 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 646 II != IE; ++II) { 647 LastMI = II; 648 649 // Print the assembly for the instruction. 650 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() && 651 !II->isDebugValue()) { 652 HasAnyRealCode = true; 653 ++EmittedInsts; 654 } 655 656 if (ShouldPrintDebugScopes) { 657 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 658 DD->beginInstruction(II); 659 } 660 661 if (isVerbose()) 662 EmitComments(*II, OutStreamer.GetCommentOS()); 663 664 switch (II->getOpcode()) { 665 case TargetOpcode::PROLOG_LABEL: 666 emitPrologLabel(*II); 667 break; 668 669 case TargetOpcode::EH_LABEL: 670 case TargetOpcode::GC_LABEL: 671 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol()); 672 break; 673 case TargetOpcode::INLINEASM: 674 EmitInlineAsm(II); 675 break; 676 case TargetOpcode::DBG_VALUE: 677 if (isVerbose()) { 678 if (!EmitDebugValueComment(II, *this)) 679 EmitInstruction(II); 680 } 681 break; 682 case TargetOpcode::IMPLICIT_DEF: 683 if (isVerbose()) EmitImplicitDef(II, *this); 684 break; 685 case TargetOpcode::KILL: 686 if (isVerbose()) EmitKill(II, *this); 687 break; 688 default: 689 if (!TM.hasMCUseLoc()) 690 MCLineEntry::Make(&OutStreamer, getCurrentSection()); 691 692 EmitInstruction(II); 693 break; 694 } 695 696 if (ShouldPrintDebugScopes) { 697 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 698 DD->endInstruction(II); 699 } 700 } 701 } 702 703 // If the last instruction was a prolog label, then we have a situation where 704 // we emitted a prolog but no function body. This results in the ending prolog 705 // label equaling the end of function label and an invalid "row" in the 706 // FDE. We need to emit a noop in this situation so that the FDE's rows are 707 // valid. 708 bool RequiresNoop = LastMI && LastMI->isPrologLabel(); 709 710 // If the function is empty and the object file uses .subsections_via_symbols, 711 // then we need to emit *something* to the function body to prevent the 712 // labels from collapsing together. Just emit a noop. 713 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) { 714 MCInst Noop; 715 TM.getInstrInfo()->getNoopForMachoTarget(Noop); 716 if (Noop.getOpcode()) { 717 OutStreamer.AddComment("avoids zero-length function"); 718 OutStreamer.EmitInstruction(Noop); 719 } else // Target not mc-ized yet. 720 OutStreamer.EmitRawText(StringRef("\tnop\n")); 721 } 722 723 // Emit target-specific gunk after the function body. 724 EmitFunctionBodyEnd(); 725 726 // If the target wants a .size directive for the size of the function, emit 727 // it. 728 if (MAI->hasDotTypeDotSizeDirective()) { 729 // Create a symbol for the end of function, so we can get the size as 730 // difference between the function label and the temp label. 731 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol(); 732 OutStreamer.EmitLabel(FnEndLabel); 733 734 const MCExpr *SizeExp = 735 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext), 736 MCSymbolRefExpr::Create(CurrentFnSym, OutContext), 737 OutContext); 738 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp); 739 } 740 741 // Emit post-function debug information. 742 if (DD) { 743 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 744 DD->endFunction(MF); 745 } 746 if (DE) { 747 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 748 DE->EndFunction(); 749 } 750 MMI->EndFunction(); 751 752 // Print out jump tables referenced by the function. 753 EmitJumpTableInfo(); 754 755 OutStreamer.AddBlankLine(); 756} 757 758/// getDebugValueLocation - Get location information encoded by DBG_VALUE 759/// operands. 760MachineLocation AsmPrinter:: 761getDebugValueLocation(const MachineInstr *MI) const { 762 // Target specific DBG_VALUE instructions are handled by each target. 763 return MachineLocation(); 764} 765 766/// EmitDwarfRegOp - Emit dwarf register operation. 767void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const { 768 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 769 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false); 770 771 for (const unsigned *SR = TRI->getSuperRegisters(MLoc.getReg()); 772 *SR && Reg == -1; ++SR) { 773 Reg = TRI->getDwarfRegNum(*SR, false); 774 // FIXME: Get the bit range this register uses of the superregister 775 // so that we can produce a DW_OP_bit_piece 776 } 777 778 // FIXME: Handle cases like a super register being encoded as 779 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33 780 781 // FIXME: We have no reasonable way of handling errors in here. The 782 // caller might be in the middle of an dwarf expression. We should 783 // probably assert that Reg >= 0 once debug info generation is more mature. 784 785 if (int Offset = MLoc.getOffset()) { 786 if (Reg < 32) { 787 OutStreamer.AddComment( 788 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg)); 789 EmitInt8(dwarf::DW_OP_breg0 + Reg); 790 } else { 791 OutStreamer.AddComment("DW_OP_bregx"); 792 EmitInt8(dwarf::DW_OP_bregx); 793 OutStreamer.AddComment(Twine(Reg)); 794 EmitULEB128(Reg); 795 } 796 EmitSLEB128(Offset); 797 } else { 798 if (Reg < 32) { 799 OutStreamer.AddComment( 800 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg)); 801 EmitInt8(dwarf::DW_OP_reg0 + Reg); 802 } else { 803 OutStreamer.AddComment("DW_OP_regx"); 804 EmitInt8(dwarf::DW_OP_regx); 805 OutStreamer.AddComment(Twine(Reg)); 806 EmitULEB128(Reg); 807 } 808 } 809 810 // FIXME: Produce a DW_OP_bit_piece if we used a superregister 811} 812 813bool AsmPrinter::doFinalization(Module &M) { 814 // Emit global variables. 815 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 816 I != E; ++I) 817 EmitGlobalVariable(I); 818 819 // Emit visibility info for declarations 820 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 821 const Function &F = *I; 822 if (!F.isDeclaration()) 823 continue; 824 GlobalValue::VisibilityTypes V = F.getVisibility(); 825 if (V == GlobalValue::DefaultVisibility) 826 continue; 827 828 MCSymbol *Name = Mang->getSymbol(&F); 829 EmitVisibility(Name, V, false); 830 } 831 832 // Finalize debug and EH information. 833 if (DE) { 834 { 835 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled); 836 DE->EndModule(); 837 } 838 delete DE; DE = 0; 839 } 840 if (DD) { 841 { 842 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 843 DD->endModule(); 844 } 845 delete DD; DD = 0; 846 } 847 848 // If the target wants to know about weak references, print them all. 849 if (MAI->getWeakRefDirective()) { 850 // FIXME: This is not lazy, it would be nice to only print weak references 851 // to stuff that is actually used. Note that doing so would require targets 852 // to notice uses in operands (due to constant exprs etc). This should 853 // happen with the MC stuff eventually. 854 855 // Print out module-level global variables here. 856 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 857 I != E; ++I) { 858 if (!I->hasExternalWeakLinkage()) continue; 859 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 860 } 861 862 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 863 if (!I->hasExternalWeakLinkage()) continue; 864 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 865 } 866 } 867 868 if (MAI->hasSetDirective()) { 869 OutStreamer.AddBlankLine(); 870 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end(); 871 I != E; ++I) { 872 MCSymbol *Name = Mang->getSymbol(I); 873 874 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal()); 875 MCSymbol *Target = Mang->getSymbol(GV); 876 877 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective()) 878 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global); 879 else if (I->hasWeakLinkage()) 880 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference); 881 else 882 assert(I->hasLocalLinkage() && "Invalid alias linkage"); 883 884 EmitVisibility(Name, I->getVisibility()); 885 886 // Emit the directives as assignments aka .set: 887 OutStreamer.EmitAssignment(Name, 888 MCSymbolRefExpr::Create(Target, OutContext)); 889 } 890 } 891 892 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 893 assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 894 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; ) 895 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I)) 896 MP->finishAssembly(*this); 897 898 // If we don't have any trampolines, then we don't require stack memory 899 // to be executable. Some targets have a directive to declare this. 900 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline"); 901 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty()) 902 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext)) 903 OutStreamer.SwitchSection(S); 904 905 // Allow the target to emit any magic that it wants at the end of the file, 906 // after everything else has gone out. 907 EmitEndOfAsmFile(M); 908 909 delete Mang; Mang = 0; 910 MMI = 0; 911 912 OutStreamer.Finish(); 913 return false; 914} 915 916void AsmPrinter::SetupMachineFunction(MachineFunction &MF) { 917 this->MF = &MF; 918 // Get the function symbol. 919 CurrentFnSym = Mang->getSymbol(MF.getFunction()); 920 921 if (isVerbose()) 922 LI = &getAnalysis<MachineLoopInfo>(); 923} 924 925namespace { 926 // SectionCPs - Keep track the alignment, constpool entries per Section. 927 struct SectionCPs { 928 const MCSection *S; 929 unsigned Alignment; 930 SmallVector<unsigned, 4> CPEs; 931 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {} 932 }; 933} 934 935/// EmitConstantPool - Print to the current output stream assembly 936/// representations of the constants in the constant pool MCP. This is 937/// used to print out constants which have been "spilled to memory" by 938/// the code generator. 939/// 940void AsmPrinter::EmitConstantPool() { 941 const MachineConstantPool *MCP = MF->getConstantPool(); 942 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants(); 943 if (CP.empty()) return; 944 945 // Calculate sections for constant pool entries. We collect entries to go into 946 // the same section together to reduce amount of section switch statements. 947 SmallVector<SectionCPs, 4> CPSections; 948 for (unsigned i = 0, e = CP.size(); i != e; ++i) { 949 const MachineConstantPoolEntry &CPE = CP[i]; 950 unsigned Align = CPE.getAlignment(); 951 952 SectionKind Kind; 953 switch (CPE.getRelocationInfo()) { 954 default: llvm_unreachable("Unknown section kind"); 955 case 2: Kind = SectionKind::getReadOnlyWithRel(); break; 956 case 1: 957 Kind = SectionKind::getReadOnlyWithRelLocal(); 958 break; 959 case 0: 960 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) { 961 case 4: Kind = SectionKind::getMergeableConst4(); break; 962 case 8: Kind = SectionKind::getMergeableConst8(); break; 963 case 16: Kind = SectionKind::getMergeableConst16();break; 964 default: Kind = SectionKind::getMergeableConst(); break; 965 } 966 } 967 968 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind); 969 970 // The number of sections are small, just do a linear search from the 971 // last section to the first. 972 bool Found = false; 973 unsigned SecIdx = CPSections.size(); 974 while (SecIdx != 0) { 975 if (CPSections[--SecIdx].S == S) { 976 Found = true; 977 break; 978 } 979 } 980 if (!Found) { 981 SecIdx = CPSections.size(); 982 CPSections.push_back(SectionCPs(S, Align)); 983 } 984 985 if (Align > CPSections[SecIdx].Alignment) 986 CPSections[SecIdx].Alignment = Align; 987 CPSections[SecIdx].CPEs.push_back(i); 988 } 989 990 // Now print stuff into the calculated sections. 991 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) { 992 OutStreamer.SwitchSection(CPSections[i].S); 993 EmitAlignment(Log2_32(CPSections[i].Alignment)); 994 995 unsigned Offset = 0; 996 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) { 997 unsigned CPI = CPSections[i].CPEs[j]; 998 MachineConstantPoolEntry CPE = CP[CPI]; 999 1000 // Emit inter-object padding for alignment. 1001 unsigned AlignMask = CPE.getAlignment() - 1; 1002 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask; 1003 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/); 1004 1005 const Type *Ty = CPE.getType(); 1006 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty); 1007 OutStreamer.EmitLabel(GetCPISymbol(CPI)); 1008 1009 if (CPE.isMachineConstantPoolEntry()) 1010 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal); 1011 else 1012 EmitGlobalConstant(CPE.Val.ConstVal); 1013 } 1014 } 1015} 1016 1017/// EmitJumpTableInfo - Print assembly representations of the jump tables used 1018/// by the current function to the current output stream. 1019/// 1020void AsmPrinter::EmitJumpTableInfo() { 1021 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 1022 if (MJTI == 0) return; 1023 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return; 1024 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 1025 if (JT.empty()) return; 1026 1027 // Pick the directive to use to print the jump table entries, and switch to 1028 // the appropriate section. 1029 const Function *F = MF->getFunction(); 1030 bool JTInDiffSection = false; 1031 if (// In PIC mode, we need to emit the jump table to the same section as the 1032 // function body itself, otherwise the label differences won't make sense. 1033 // FIXME: Need a better predicate for this: what about custom entries? 1034 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 || 1035 // We should also do if the section name is NULL or function is declared 1036 // in discardable section 1037 // FIXME: this isn't the right predicate, should be based on the MCSection 1038 // for the function. 1039 F->isWeakForLinker()) { 1040 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM)); 1041 } else { 1042 // Otherwise, drop it in the readonly section. 1043 const MCSection *ReadOnlySection = 1044 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly()); 1045 OutStreamer.SwitchSection(ReadOnlySection); 1046 JTInDiffSection = true; 1047 } 1048 1049 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData()))); 1050 1051 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) { 1052 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 1053 1054 // If this jump table was deleted, ignore it. 1055 if (JTBBs.empty()) continue; 1056 1057 // For the EK_LabelDifference32 entry, if the target supports .set, emit a 1058 // .set directive for each unique entry. This reduces the number of 1059 // relocations the assembler will generate for the jump table. 1060 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 && 1061 MAI->hasSetDirective()) { 1062 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets; 1063 const TargetLowering *TLI = TM.getTargetLowering(); 1064 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext); 1065 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) { 1066 const MachineBasicBlock *MBB = JTBBs[ii]; 1067 if (!EmittedSets.insert(MBB)) continue; 1068 1069 // .set LJTSet, LBB32-base 1070 const MCExpr *LHS = 1071 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1072 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()), 1073 MCBinaryExpr::CreateSub(LHS, Base, OutContext)); 1074 } 1075 } 1076 1077 // On some targets (e.g. Darwin) we want to emit two consecutive labels 1078 // before each jump table. The first label is never referenced, but tells 1079 // the assembler and linker the extents of the jump table object. The 1080 // second label is actually referenced by the code. 1081 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0]) 1082 // FIXME: This doesn't have to have any specific name, just any randomly 1083 // named and numbered 'l' label would work. Simplify GetJTISymbol. 1084 OutStreamer.EmitLabel(GetJTISymbol(JTI, true)); 1085 1086 OutStreamer.EmitLabel(GetJTISymbol(JTI)); 1087 1088 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) 1089 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI); 1090 } 1091} 1092 1093/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the 1094/// current stream. 1095void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI, 1096 const MachineBasicBlock *MBB, 1097 unsigned UID) const { 1098 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block"); 1099 const MCExpr *Value = 0; 1100 switch (MJTI->getEntryKind()) { 1101 case MachineJumpTableInfo::EK_Inline: 1102 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break; 1103 case MachineJumpTableInfo::EK_Custom32: 1104 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID, 1105 OutContext); 1106 break; 1107 case MachineJumpTableInfo::EK_BlockAddress: 1108 // EK_BlockAddress - Each entry is a plain address of block, e.g.: 1109 // .word LBB123 1110 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1111 break; 1112 case MachineJumpTableInfo::EK_GPRel32BlockAddress: { 1113 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded 1114 // with a relocation as gp-relative, e.g.: 1115 // .gprel32 LBB123 1116 MCSymbol *MBBSym = MBB->getSymbol(); 1117 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 1118 return; 1119 } 1120 1121 case MachineJumpTableInfo::EK_LabelDifference32: { 1122 // EK_LabelDifference32 - Each entry is the address of the block minus 1123 // the address of the jump table. This is used for PIC jump tables where 1124 // gprel32 is not supported. e.g.: 1125 // .word LBB123 - LJTI1_2 1126 // If the .set directive is supported, this is emitted as: 1127 // .set L4_5_set_123, LBB123 - LJTI1_2 1128 // .word L4_5_set_123 1129 1130 // If we have emitted set directives for the jump table entries, print 1131 // them rather than the entries themselves. If we're emitting PIC, then 1132 // emit the table entries as differences between two text section labels. 1133 if (MAI->hasSetDirective()) { 1134 // If we used .set, reference the .set's symbol. 1135 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()), 1136 OutContext); 1137 break; 1138 } 1139 // Otherwise, use the difference as the jump table entry. 1140 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 1141 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext); 1142 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext); 1143 break; 1144 } 1145 } 1146 1147 assert(Value && "Unknown entry kind!"); 1148 1149 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData()); 1150 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0); 1151} 1152 1153 1154/// EmitSpecialLLVMGlobal - Check to see if the specified global is a 1155/// special global used by LLVM. If so, emit it and return true, otherwise 1156/// do nothing and return false. 1157bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) { 1158 if (GV->getName() == "llvm.used") { 1159 if (MAI->hasNoDeadStrip()) // No need to emit this at all. 1160 EmitLLVMUsedList(GV->getInitializer()); 1161 return true; 1162 } 1163 1164 // Ignore debug and non-emitted data. This handles llvm.compiler.used. 1165 if (GV->getSection() == "llvm.metadata" || 1166 GV->hasAvailableExternallyLinkage()) 1167 return true; 1168 1169 if (!GV->hasAppendingLinkage()) return false; 1170 1171 assert(GV->hasInitializer() && "Not a special LLVM global!"); 1172 1173 const TargetData *TD = TM.getTargetData(); 1174 unsigned Align = Log2_32(TD->getPointerPrefAlignment()); 1175 if (GV->getName() == "llvm.global_ctors") { 1176 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection()); 1177 EmitAlignment(Align); 1178 EmitXXStructorList(GV->getInitializer()); 1179 1180 if (TM.getRelocationModel() == Reloc::Static && 1181 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1182 StringRef Sym(".constructors_used"); 1183 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1184 MCSA_Reference); 1185 } 1186 return true; 1187 } 1188 1189 if (GV->getName() == "llvm.global_dtors") { 1190 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection()); 1191 EmitAlignment(Align); 1192 EmitXXStructorList(GV->getInitializer()); 1193 1194 if (TM.getRelocationModel() == Reloc::Static && 1195 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 1196 StringRef Sym(".destructors_used"); 1197 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 1198 MCSA_Reference); 1199 } 1200 return true; 1201 } 1202 1203 return false; 1204} 1205 1206/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each 1207/// global in the specified llvm.used list for which emitUsedDirectiveFor 1208/// is true, as being used with this directive. 1209void AsmPrinter::EmitLLVMUsedList(Constant *List) { 1210 // Should be an array of 'i8*'. 1211 ConstantArray *InitList = dyn_cast<ConstantArray>(List); 1212 if (InitList == 0) return; 1213 1214 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 1215 const GlobalValue *GV = 1216 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts()); 1217 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang)) 1218 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip); 1219 } 1220} 1221 1222/// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the 1223/// function pointers, ignoring the init priority. 1224void AsmPrinter::EmitXXStructorList(Constant *List) { 1225 // Should be an array of '{ int, void ()* }' structs. The first value is the 1226 // init priority, which we ignore. 1227 if (!isa<ConstantArray>(List)) return; 1228 ConstantArray *InitList = cast<ConstantArray>(List); 1229 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 1230 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){ 1231 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs. 1232 1233 if (CS->getOperand(1)->isNullValue()) 1234 return; // Found a null terminator, exit printing. 1235 // Emit the function pointer. 1236 EmitGlobalConstant(CS->getOperand(1)); 1237 } 1238} 1239 1240//===--------------------------------------------------------------------===// 1241// Emission and print routines 1242// 1243 1244/// EmitInt8 - Emit a byte directive and value. 1245/// 1246void AsmPrinter::EmitInt8(int Value) const { 1247 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/); 1248} 1249 1250/// EmitInt16 - Emit a short directive and value. 1251/// 1252void AsmPrinter::EmitInt16(int Value) const { 1253 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/); 1254} 1255 1256/// EmitInt32 - Emit a long directive and value. 1257/// 1258void AsmPrinter::EmitInt32(int Value) const { 1259 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/); 1260} 1261 1262/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size 1263/// in bytes of the directive is specified by Size and Hi/Lo specify the 1264/// labels. This implicitly uses .set if it is available. 1265void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, 1266 unsigned Size) const { 1267 // Get the Hi-Lo expression. 1268 const MCExpr *Diff = 1269 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext), 1270 MCSymbolRefExpr::Create(Lo, OutContext), 1271 OutContext); 1272 1273 if (!MAI->hasSetDirective()) { 1274 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/); 1275 return; 1276 } 1277 1278 // Otherwise, emit with .set (aka assignment). 1279 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1280 OutStreamer.EmitAssignment(SetLabel, Diff); 1281 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/); 1282} 1283 1284/// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo" 1285/// where the size in bytes of the directive is specified by Size and Hi/Lo 1286/// specify the labels. This implicitly uses .set if it is available. 1287void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset, 1288 const MCSymbol *Lo, unsigned Size) 1289 const { 1290 1291 // Emit Hi+Offset - Lo 1292 // Get the Hi+Offset expression. 1293 const MCExpr *Plus = 1294 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext), 1295 MCConstantExpr::Create(Offset, OutContext), 1296 OutContext); 1297 1298 // Get the Hi+Offset-Lo expression. 1299 const MCExpr *Diff = 1300 MCBinaryExpr::CreateSub(Plus, 1301 MCSymbolRefExpr::Create(Lo, OutContext), 1302 OutContext); 1303 1304 if (!MAI->hasSetDirective()) 1305 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/); 1306 else { 1307 // Otherwise, emit with .set (aka assignment). 1308 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++); 1309 OutStreamer.EmitAssignment(SetLabel, Diff); 1310 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/); 1311 } 1312} 1313 1314/// EmitLabelPlusOffset - Emit something like ".long Label+Offset" 1315/// where the size in bytes of the directive is specified by Size and Label 1316/// specifies the label. This implicitly uses .set if it is available. 1317void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset, 1318 unsigned Size) 1319 const { 1320 1321 // Emit Label+Offset 1322 const MCExpr *Plus = 1323 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Label, OutContext), 1324 MCConstantExpr::Create(Offset, OutContext), 1325 OutContext); 1326 1327 OutStreamer.EmitValue(Plus, 4, 0/*AddrSpace*/); 1328} 1329 1330 1331//===----------------------------------------------------------------------===// 1332 1333// EmitAlignment - Emit an alignment directive to the specified power of 1334// two boundary. For example, if you pass in 3 here, you will get an 8 1335// byte alignment. If a global value is specified, and if that global has 1336// an explicit alignment requested, it will override the alignment request 1337// if required for correctness. 1338// 1339void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const { 1340 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getTargetData(), NumBits); 1341 1342 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment. 1343 1344 if (getCurrentSection()->getKind().isText()) 1345 OutStreamer.EmitCodeAlignment(1 << NumBits); 1346 else 1347 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0); 1348} 1349 1350//===----------------------------------------------------------------------===// 1351// Constant emission. 1352//===----------------------------------------------------------------------===// 1353 1354/// LowerConstant - Lower the specified LLVM Constant to an MCExpr. 1355/// 1356static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) { 1357 MCContext &Ctx = AP.OutContext; 1358 1359 if (CV->isNullValue() || isa<UndefValue>(CV)) 1360 return MCConstantExpr::Create(0, Ctx); 1361 1362 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) 1363 return MCConstantExpr::Create(CI->getZExtValue(), Ctx); 1364 1365 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 1366 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx); 1367 1368 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV)) 1369 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx); 1370 1371 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV); 1372 if (CE == 0) { 1373 llvm_unreachable("Unknown constant value to lower!"); 1374 return MCConstantExpr::Create(0, Ctx); 1375 } 1376 1377 switch (CE->getOpcode()) { 1378 default: 1379 // If the code isn't optimized, there may be outstanding folding 1380 // opportunities. Attempt to fold the expression using TargetData as a 1381 // last resort before giving up. 1382 if (Constant *C = 1383 ConstantFoldConstantExpression(CE, AP.TM.getTargetData())) 1384 if (C != CE) 1385 return LowerConstant(C, AP); 1386 1387 // Otherwise report the problem to the user. 1388 { 1389 std::string S; 1390 raw_string_ostream OS(S); 1391 OS << "Unsupported expression in static initializer: "; 1392 WriteAsOperand(OS, CE, /*PrintType=*/false, 1393 !AP.MF ? 0 : AP.MF->getFunction()->getParent()); 1394 report_fatal_error(OS.str()); 1395 } 1396 return MCConstantExpr::Create(0, Ctx); 1397 case Instruction::GetElementPtr: { 1398 const TargetData &TD = *AP.TM.getTargetData(); 1399 // Generate a symbolic expression for the byte address 1400 const Constant *PtrVal = CE->getOperand(0); 1401 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end()); 1402 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0], 1403 IdxVec.size()); 1404 1405 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP); 1406 if (Offset == 0) 1407 return Base; 1408 1409 // Truncate/sext the offset to the pointer size. 1410 if (TD.getPointerSizeInBits() != 64) { 1411 int SExtAmount = 64-TD.getPointerSizeInBits(); 1412 Offset = (Offset << SExtAmount) >> SExtAmount; 1413 } 1414 1415 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx), 1416 Ctx); 1417 } 1418 1419 case Instruction::Trunc: 1420 // We emit the value and depend on the assembler to truncate the generated 1421 // expression properly. This is important for differences between 1422 // blockaddress labels. Since the two labels are in the same function, it 1423 // is reasonable to treat their delta as a 32-bit value. 1424 // FALL THROUGH. 1425 case Instruction::BitCast: 1426 return LowerConstant(CE->getOperand(0), AP); 1427 1428 case Instruction::IntToPtr: { 1429 const TargetData &TD = *AP.TM.getTargetData(); 1430 // Handle casts to pointers by changing them into casts to the appropriate 1431 // integer type. This promotes constant folding and simplifies this code. 1432 Constant *Op = CE->getOperand(0); 1433 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()), 1434 false/*ZExt*/); 1435 return LowerConstant(Op, AP); 1436 } 1437 1438 case Instruction::PtrToInt: { 1439 const TargetData &TD = *AP.TM.getTargetData(); 1440 // Support only foldable casts to/from pointers that can be eliminated by 1441 // changing the pointer to the appropriately sized integer type. 1442 Constant *Op = CE->getOperand(0); 1443 const Type *Ty = CE->getType(); 1444 1445 const MCExpr *OpExpr = LowerConstant(Op, AP); 1446 1447 // We can emit the pointer value into this slot if the slot is an 1448 // integer slot equal to the size of the pointer. 1449 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType())) 1450 return OpExpr; 1451 1452 // Otherwise the pointer is smaller than the resultant integer, mask off 1453 // the high bits so we are sure to get a proper truncation if the input is 1454 // a constant expr. 1455 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType()); 1456 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx); 1457 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx); 1458 } 1459 1460 // The MC library also has a right-shift operator, but it isn't consistently 1461 // signed or unsigned between different targets. 1462 case Instruction::Add: 1463 case Instruction::Sub: 1464 case Instruction::Mul: 1465 case Instruction::SDiv: 1466 case Instruction::SRem: 1467 case Instruction::Shl: 1468 case Instruction::And: 1469 case Instruction::Or: 1470 case Instruction::Xor: { 1471 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP); 1472 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP); 1473 switch (CE->getOpcode()) { 1474 default: llvm_unreachable("Unknown binary operator constant cast expr"); 1475 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx); 1476 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx); 1477 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx); 1478 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx); 1479 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx); 1480 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx); 1481 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx); 1482 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx); 1483 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx); 1484 } 1485 } 1486 } 1487} 1488 1489static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace, 1490 AsmPrinter &AP); 1491 1492static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace, 1493 AsmPrinter &AP) { 1494 if (AddrSpace != 0 || !CA->isString()) { 1495 // Not a string. Print the values in successive locations 1496 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1497 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP); 1498 return; 1499 } 1500 1501 // Otherwise, it can be emitted as .ascii. 1502 SmallVector<char, 128> TmpVec; 1503 TmpVec.reserve(CA->getNumOperands()); 1504 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1505 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue()); 1506 1507 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace); 1508} 1509 1510static void EmitGlobalConstantVector(const ConstantVector *CV, 1511 unsigned AddrSpace, AsmPrinter &AP) { 1512 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i) 1513 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP); 1514} 1515 1516static void EmitGlobalConstantStruct(const ConstantStruct *CS, 1517 unsigned AddrSpace, AsmPrinter &AP) { 1518 // Print the fields in successive locations. Pad to align if needed! 1519 const TargetData *TD = AP.TM.getTargetData(); 1520 unsigned Size = TD->getTypeAllocSize(CS->getType()); 1521 const StructLayout *Layout = TD->getStructLayout(CS->getType()); 1522 uint64_t SizeSoFar = 0; 1523 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 1524 const Constant *Field = CS->getOperand(i); 1525 1526 // Check if padding is needed and insert one or more 0s. 1527 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType()); 1528 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1)) 1529 - Layout->getElementOffset(i)) - FieldSize; 1530 SizeSoFar += FieldSize + PadSize; 1531 1532 // Now print the actual field value. 1533 EmitGlobalConstantImpl(Field, AddrSpace, AP); 1534 1535 // Insert padding - this may include padding to increase the size of the 1536 // current field up to the ABI size (if the struct is not packed) as well 1537 // as padding to ensure that the next field starts at the right offset. 1538 AP.OutStreamer.EmitZeros(PadSize, AddrSpace); 1539 } 1540 assert(SizeSoFar == Layout->getSizeInBytes() && 1541 "Layout of constant struct may be incorrect!"); 1542} 1543 1544static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace, 1545 AsmPrinter &AP) { 1546 // FP Constants are printed as integer constants to avoid losing 1547 // precision. 1548 if (CFP->getType()->isDoubleTy()) { 1549 if (AP.isVerbose()) { 1550 double Val = CFP->getValueAPF().convertToDouble(); 1551 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n'; 1552 } 1553 1554 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1555 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1556 return; 1557 } 1558 1559 if (CFP->getType()->isFloatTy()) { 1560 if (AP.isVerbose()) { 1561 float Val = CFP->getValueAPF().convertToFloat(); 1562 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n'; 1563 } 1564 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1565 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace); 1566 return; 1567 } 1568 1569 if (CFP->getType()->isX86_FP80Ty()) { 1570 // all long double variants are printed as hex 1571 // API needed to prevent premature destruction 1572 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1573 const uint64_t *p = API.getRawData(); 1574 if (AP.isVerbose()) { 1575 // Convert to double so we can print the approximate val as a comment. 1576 APFloat DoubleVal = CFP->getValueAPF(); 1577 bool ignored; 1578 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 1579 &ignored); 1580 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= " 1581 << DoubleVal.convertToDouble() << '\n'; 1582 } 1583 1584 if (AP.TM.getTargetData()->isBigEndian()) { 1585 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1586 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1587 } else { 1588 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1589 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1590 } 1591 1592 // Emit the tail padding for the long double. 1593 const TargetData &TD = *AP.TM.getTargetData(); 1594 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) - 1595 TD.getTypeStoreSize(CFP->getType()), AddrSpace); 1596 return; 1597 } 1598 1599 assert(CFP->getType()->isPPC_FP128Ty() && 1600 "Floating point constant type not handled"); 1601 // All long double variants are printed as hex 1602 // API needed to prevent premature destruction. 1603 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1604 const uint64_t *p = API.getRawData(); 1605 if (AP.TM.getTargetData()->isBigEndian()) { 1606 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1607 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1608 } else { 1609 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1610 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1611 } 1612} 1613 1614static void EmitGlobalConstantLargeInt(const ConstantInt *CI, 1615 unsigned AddrSpace, AsmPrinter &AP) { 1616 const TargetData *TD = AP.TM.getTargetData(); 1617 unsigned BitWidth = CI->getBitWidth(); 1618 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits"); 1619 1620 // We don't expect assemblers to support integer data directives 1621 // for more than 64 bits, so we emit the data in at most 64-bit 1622 // quantities at a time. 1623 const uint64_t *RawData = CI->getValue().getRawData(); 1624 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) { 1625 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i]; 1626 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1627 } 1628} 1629 1630static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace, 1631 AsmPrinter &AP) { 1632 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) { 1633 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1634 return AP.OutStreamer.EmitZeros(Size, AddrSpace); 1635 } 1636 1637 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { 1638 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1639 switch (Size) { 1640 case 1: 1641 case 2: 1642 case 4: 1643 case 8: 1644 if (AP.isVerbose()) 1645 AP.OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue()); 1646 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace); 1647 return; 1648 default: 1649 EmitGlobalConstantLargeInt(CI, AddrSpace, AP); 1650 return; 1651 } 1652 } 1653 1654 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) 1655 return EmitGlobalConstantArray(CVA, AddrSpace, AP); 1656 1657 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) 1658 return EmitGlobalConstantStruct(CVS, AddrSpace, AP); 1659 1660 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) 1661 return EmitGlobalConstantFP(CFP, AddrSpace, AP); 1662 1663 if (isa<ConstantPointerNull>(CV)) { 1664 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType()); 1665 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace); 1666 return; 1667 } 1668 1669 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV)) 1670 return EmitGlobalConstantVector(V, AddrSpace, AP); 1671 1672 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it 1673 // thread the streamer with EmitValue. 1674 AP.OutStreamer.EmitValue(LowerConstant(CV, AP), 1675 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()), 1676 AddrSpace); 1677} 1678 1679/// EmitGlobalConstant - Print a general LLVM constant to the .s file. 1680void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) { 1681 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1682 if (Size) 1683 EmitGlobalConstantImpl(CV, AddrSpace, *this); 1684 else if (MAI->hasSubsectionsViaSymbols()) { 1685 // If the global has zero size, emit a single byte so that two labels don't 1686 // look like they are at the same location. 1687 OutStreamer.EmitIntValue(0, 1, AddrSpace); 1688 } 1689} 1690 1691void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 1692 // Target doesn't support this yet! 1693 llvm_unreachable("Target does not support EmitMachineConstantPoolValue"); 1694} 1695 1696void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const { 1697 if (Offset > 0) 1698 OS << '+' << Offset; 1699 else if (Offset < 0) 1700 OS << Offset; 1701} 1702 1703//===----------------------------------------------------------------------===// 1704// Symbol Lowering Routines. 1705//===----------------------------------------------------------------------===// 1706 1707/// GetTempSymbol - Return the MCSymbol corresponding to the assembler 1708/// temporary label with the specified stem and unique ID. 1709MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const { 1710 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + 1711 Name + Twine(ID)); 1712} 1713 1714/// GetTempSymbol - Return an assembler temporary label with the specified 1715/// stem. 1716MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const { 1717 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+ 1718 Name); 1719} 1720 1721 1722MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const { 1723 return MMI->getAddrLabelSymbol(BA->getBasicBlock()); 1724} 1725 1726MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const { 1727 return MMI->getAddrLabelSymbol(BB); 1728} 1729 1730/// GetCPISymbol - Return the symbol for the specified constant pool entry. 1731MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const { 1732 return OutContext.GetOrCreateSymbol 1733 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber()) 1734 + "_" + Twine(CPID)); 1735} 1736 1737/// GetJTISymbol - Return the symbol for the specified jump table entry. 1738MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const { 1739 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate); 1740} 1741 1742/// GetJTSetSymbol - Return the symbol for the specified jump table .set 1743/// FIXME: privatize to AsmPrinter. 1744MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const { 1745 return OutContext.GetOrCreateSymbol 1746 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" + 1747 Twine(UID) + "_set_" + Twine(MBBID)); 1748} 1749 1750/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with 1751/// global value name as its base, with the specified suffix, and where the 1752/// symbol is forced to have private linkage if ForcePrivate is true. 1753MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV, 1754 StringRef Suffix, 1755 bool ForcePrivate) const { 1756 SmallString<60> NameStr; 1757 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate); 1758 NameStr.append(Suffix.begin(), Suffix.end()); 1759 return OutContext.GetOrCreateSymbol(NameStr.str()); 1760} 1761 1762/// GetExternalSymbolSymbol - Return the MCSymbol for the specified 1763/// ExternalSymbol. 1764MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const { 1765 SmallString<60> NameStr; 1766 Mang->getNameWithPrefix(NameStr, Sym); 1767 return OutContext.GetOrCreateSymbol(NameStr.str()); 1768} 1769 1770 1771 1772/// PrintParentLoopComment - Print comments about parent loops of this one. 1773static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1774 unsigned FunctionNumber) { 1775 if (Loop == 0) return; 1776 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber); 1777 OS.indent(Loop->getLoopDepth()*2) 1778 << "Parent Loop BB" << FunctionNumber << "_" 1779 << Loop->getHeader()->getNumber() 1780 << " Depth=" << Loop->getLoopDepth() << '\n'; 1781} 1782 1783 1784/// PrintChildLoopComment - Print comments about child loops within 1785/// the loop for this basic block, with nesting. 1786static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1787 unsigned FunctionNumber) { 1788 // Add child loop information 1789 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){ 1790 OS.indent((*CL)->getLoopDepth()*2) 1791 << "Child Loop BB" << FunctionNumber << "_" 1792 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth() 1793 << '\n'; 1794 PrintChildLoopComment(OS, *CL, FunctionNumber); 1795 } 1796} 1797 1798/// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks. 1799static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB, 1800 const MachineLoopInfo *LI, 1801 const AsmPrinter &AP) { 1802 // Add loop depth information 1803 const MachineLoop *Loop = LI->getLoopFor(&MBB); 1804 if (Loop == 0) return; 1805 1806 MachineBasicBlock *Header = Loop->getHeader(); 1807 assert(Header && "No header for loop"); 1808 1809 // If this block is not a loop header, just print out what is the loop header 1810 // and return. 1811 if (Header != &MBB) { 1812 AP.OutStreamer.AddComment(" in Loop: Header=BB" + 1813 Twine(AP.getFunctionNumber())+"_" + 1814 Twine(Loop->getHeader()->getNumber())+ 1815 " Depth="+Twine(Loop->getLoopDepth())); 1816 return; 1817 } 1818 1819 // Otherwise, it is a loop header. Print out information about child and 1820 // parent loops. 1821 raw_ostream &OS = AP.OutStreamer.GetCommentOS(); 1822 1823 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 1824 1825 OS << "=>"; 1826 OS.indent(Loop->getLoopDepth()*2-2); 1827 1828 OS << "This "; 1829 if (Loop->empty()) 1830 OS << "Inner "; 1831 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n'; 1832 1833 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber()); 1834} 1835 1836 1837/// EmitBasicBlockStart - This method prints the label for the specified 1838/// MachineBasicBlock, an alignment (if present) and a comment describing 1839/// it if appropriate. 1840void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const { 1841 // Emit an alignment directive for this block, if needed. 1842 if (unsigned Align = MBB->getAlignment()) 1843 EmitAlignment(Log2_32(Align)); 1844 1845 // If the block has its address taken, emit any labels that were used to 1846 // reference the block. It is possible that there is more than one label 1847 // here, because multiple LLVM BB's may have been RAUW'd to this block after 1848 // the references were generated. 1849 if (MBB->hasAddressTaken()) { 1850 const BasicBlock *BB = MBB->getBasicBlock(); 1851 if (isVerbose()) 1852 OutStreamer.AddComment("Block address taken"); 1853 1854 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB); 1855 1856 for (unsigned i = 0, e = Syms.size(); i != e; ++i) 1857 OutStreamer.EmitLabel(Syms[i]); 1858 } 1859 1860 // Print the main label for the block. 1861 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) { 1862 if (isVerbose() && OutStreamer.hasRawTextSupport()) { 1863 if (const BasicBlock *BB = MBB->getBasicBlock()) 1864 if (BB->hasName()) 1865 OutStreamer.AddComment("%" + BB->getName()); 1866 1867 EmitBasicBlockLoopComments(*MBB, LI, *this); 1868 1869 // NOTE: Want this comment at start of line, don't emit with AddComment. 1870 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" + 1871 Twine(MBB->getNumber()) + ":"); 1872 } 1873 } else { 1874 if (isVerbose()) { 1875 if (const BasicBlock *BB = MBB->getBasicBlock()) 1876 if (BB->hasName()) 1877 OutStreamer.AddComment("%" + BB->getName()); 1878 EmitBasicBlockLoopComments(*MBB, LI, *this); 1879 } 1880 1881 OutStreamer.EmitLabel(MBB->getSymbol()); 1882 } 1883} 1884 1885void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility, 1886 bool IsDefinition) const { 1887 MCSymbolAttr Attr = MCSA_Invalid; 1888 1889 switch (Visibility) { 1890 default: break; 1891 case GlobalValue::HiddenVisibility: 1892 if (IsDefinition) 1893 Attr = MAI->getHiddenVisibilityAttr(); 1894 else 1895 Attr = MAI->getHiddenDeclarationVisibilityAttr(); 1896 break; 1897 case GlobalValue::ProtectedVisibility: 1898 Attr = MAI->getProtectedVisibilityAttr(); 1899 break; 1900 } 1901 1902 if (Attr != MCSA_Invalid) 1903 OutStreamer.EmitSymbolAttribute(Sym, Attr); 1904} 1905 1906/// isBlockOnlyReachableByFallthough - Return true if the basic block has 1907/// exactly one predecessor and the control transfer mechanism between 1908/// the predecessor and this block is a fall-through. 1909bool AsmPrinter:: 1910isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const { 1911 // If this is a landing pad, it isn't a fall through. If it has no preds, 1912 // then nothing falls through to it. 1913 if (MBB->isLandingPad() || MBB->pred_empty()) 1914 return false; 1915 1916 // If there isn't exactly one predecessor, it can't be a fall through. 1917 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI; 1918 ++PI2; 1919 if (PI2 != MBB->pred_end()) 1920 return false; 1921 1922 // The predecessor has to be immediately before this block. 1923 const MachineBasicBlock *Pred = *PI; 1924 1925 if (!Pred->isLayoutSuccessor(MBB)) 1926 return false; 1927 1928 // If the block is completely empty, then it definitely does fall through. 1929 if (Pred->empty()) 1930 return true; 1931 1932 // Otherwise, check the last instruction. 1933 const MachineInstr &LastInst = Pred->back(); 1934 return !LastInst.getDesc().isBarrier(); 1935} 1936 1937 1938 1939GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) { 1940 if (!S->usesMetadata()) 1941 return 0; 1942 1943 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters); 1944 gcp_map_type::iterator GCPI = GCMap.find(S); 1945 if (GCPI != GCMap.end()) 1946 return GCPI->second; 1947 1948 const char *Name = S->getName().c_str(); 1949 1950 for (GCMetadataPrinterRegistry::iterator 1951 I = GCMetadataPrinterRegistry::begin(), 1952 E = GCMetadataPrinterRegistry::end(); I != E; ++I) 1953 if (strcmp(Name, I->getName()) == 0) { 1954 GCMetadataPrinter *GMP = I->instantiate(); 1955 GMP->S = S; 1956 GCMap.insert(std::make_pair(S, GMP)); 1957 return GMP; 1958 } 1959 1960 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name)); 1961 return 0; 1962} 1963 1964