1 //===- lib/MC/MCAssembler.cpp - Assembler Backend Implementation ----------===// 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 #include "llvm/MC/MCAssembler.h" 11 #include "llvm/ADT/Statistic.h" 12 #include "llvm/ADT/StringExtras.h" 13 #include "llvm/ADT/Twine.h" 14 #include "llvm/MC/MCAsmBackend.h" 15 #include "llvm/MC/MCAsmInfo.h" 16 #include "llvm/MC/MCAsmLayout.h" 17 #include "llvm/MC/MCCodeEmitter.h" 18 #include "llvm/MC/MCContext.h" 19 #include "llvm/MC/MCDwarf.h" 20 #include "llvm/MC/MCExpr.h" 21 #include "llvm/MC/MCFixupKindInfo.h" 22 #include "llvm/MC/MCObjectWriter.h" 23 #include "llvm/MC/MCSection.h" 24 #include "llvm/MC/MCSectionELF.h" 25 #include "llvm/MC/MCSymbol.h" 26 #include "llvm/MC/MCValue.h" 27 #include "llvm/Support/Debug.h" 28 #include "llvm/Support/ErrorHandling.h" 29 #include "llvm/Support/LEB128.h" 30 #include "llvm/Support/TargetRegistry.h" 31 #include "llvm/Support/raw_ostream.h" 32 #include <tuple> 33 using namespace llvm; 34 35 #define DEBUG_TYPE "assembler" 36 37 namespace { 38 namespace stats { 39 STATISTIC(EmittedFragments, "Number of emitted assembler fragments - total"); 40 STATISTIC(EmittedRelaxableFragments, 41 "Number of emitted assembler fragments - relaxable"); 42 STATISTIC(EmittedDataFragments, 43 "Number of emitted assembler fragments - data"); 44 STATISTIC(EmittedCompactEncodedInstFragments, 45 "Number of emitted assembler fragments - compact encoded inst"); 46 STATISTIC(EmittedAlignFragments, 47 "Number of emitted assembler fragments - align"); 48 STATISTIC(EmittedFillFragments, 49 "Number of emitted assembler fragments - fill"); 50 STATISTIC(EmittedOrgFragments, 51 "Number of emitted assembler fragments - org"); 52 STATISTIC(evaluateFixup, "Number of evaluated fixups"); 53 STATISTIC(FragmentLayouts, "Number of fragment layouts"); 54 STATISTIC(ObjectBytes, "Number of emitted object file bytes"); 55 STATISTIC(RelaxationSteps, "Number of assembler layout and relaxation steps"); 56 STATISTIC(RelaxedInstructions, "Number of relaxed instructions"); 57 } 58 } 59 60 // FIXME FIXME FIXME: There are number of places in this file where we convert 61 // what is a 64-bit assembler value used for computation into a value in the 62 // object file, which may truncate it. We should detect that truncation where 63 // invalid and report errors back. 64 65 /* *** */ 66 67 MCAsmLayout::MCAsmLayout(MCAssembler &Asm) 68 : Assembler(Asm), LastValidFragment() 69 { 70 // Compute the section layout order. Virtual sections must go last. 71 for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) 72 if (!it->getSection().isVirtualSection()) 73 SectionOrder.push_back(&*it); 74 for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) 75 if (it->getSection().isVirtualSection()) 76 SectionOrder.push_back(&*it); 77 } 78 79 bool MCAsmLayout::isFragmentValid(const MCFragment *F) const { 80 const MCSectionData &SD = *F->getParent(); 81 const MCFragment *LastValid = LastValidFragment.lookup(&SD); 82 if (!LastValid) 83 return false; 84 assert(LastValid->getParent() == F->getParent()); 85 return F->getLayoutOrder() <= LastValid->getLayoutOrder(); 86 } 87 88 void MCAsmLayout::invalidateFragmentsFrom(MCFragment *F) { 89 // If this fragment wasn't already valid, we don't need to do anything. 90 if (!isFragmentValid(F)) 91 return; 92 93 // Otherwise, reset the last valid fragment to the previous fragment 94 // (if this is the first fragment, it will be NULL). 95 const MCSectionData &SD = *F->getParent(); 96 LastValidFragment[&SD] = F->getPrevNode(); 97 } 98 99 void MCAsmLayout::ensureValid(const MCFragment *F) const { 100 MCSectionData &SD = *F->getParent(); 101 102 MCFragment *Cur = LastValidFragment[&SD]; 103 if (!Cur) 104 Cur = &*SD.begin(); 105 else 106 Cur = Cur->getNextNode(); 107 108 // Advance the layout position until the fragment is valid. 109 while (!isFragmentValid(F)) { 110 assert(Cur && "Layout bookkeeping error"); 111 const_cast<MCAsmLayout*>(this)->layoutFragment(Cur); 112 Cur = Cur->getNextNode(); 113 } 114 } 115 116 uint64_t MCAsmLayout::getFragmentOffset(const MCFragment *F) const { 117 ensureValid(F); 118 assert(F->Offset != ~UINT64_C(0) && "Address not set!"); 119 return F->Offset; 120 } 121 122 // Simple getSymbolOffset helper for the non-varibale case. 123 static bool getLabelOffset(const MCAsmLayout &Layout, const MCSymbolData &SD, 124 bool ReportError, uint64_t &Val) { 125 if (!SD.getFragment()) { 126 if (ReportError) 127 report_fatal_error("unable to evaluate offset to undefined symbol '" + 128 SD.getSymbol().getName() + "'"); 129 return false; 130 } 131 Val = Layout.getFragmentOffset(SD.getFragment()) + SD.getOffset(); 132 return true; 133 } 134 135 static bool getSymbolOffsetImpl(const MCAsmLayout &Layout, 136 const MCSymbolData *SD, bool ReportError, 137 uint64_t &Val) { 138 const MCSymbol &S = SD->getSymbol(); 139 140 if (!S.isVariable()) 141 return getLabelOffset(Layout, *SD, ReportError, Val); 142 143 // If SD is a variable, evaluate it. 144 MCValue Target; 145 if (!S.getVariableValue()->EvaluateAsRelocatable(Target, &Layout, nullptr)) 146 report_fatal_error("unable to evaluate offset for variable '" + 147 S.getName() + "'"); 148 149 uint64_t Offset = Target.getConstant(); 150 151 const MCAssembler &Asm = Layout.getAssembler(); 152 153 const MCSymbolRefExpr *A = Target.getSymA(); 154 if (A) { 155 uint64_t ValA; 156 if (!getLabelOffset(Layout, Asm.getSymbolData(A->getSymbol()), ReportError, 157 ValA)) 158 return false; 159 Offset += ValA; 160 } 161 162 const MCSymbolRefExpr *B = Target.getSymB(); 163 if (B) { 164 uint64_t ValB; 165 if (!getLabelOffset(Layout, Asm.getSymbolData(B->getSymbol()), ReportError, 166 ValB)) 167 return false; 168 Offset -= ValB; 169 } 170 171 Val = Offset; 172 return true; 173 } 174 175 bool MCAsmLayout::getSymbolOffset(const MCSymbolData *SD, uint64_t &Val) const { 176 return getSymbolOffsetImpl(*this, SD, false, Val); 177 } 178 179 uint64_t MCAsmLayout::getSymbolOffset(const MCSymbolData *SD) const { 180 uint64_t Val; 181 getSymbolOffsetImpl(*this, SD, true, Val); 182 return Val; 183 } 184 185 const MCSymbol *MCAsmLayout::getBaseSymbol(const MCSymbol &Symbol) const { 186 if (!Symbol.isVariable()) 187 return &Symbol; 188 189 const MCExpr *Expr = Symbol.getVariableValue(); 190 MCValue Value; 191 if (!Expr->evaluateAsValue(Value, *this)) 192 llvm_unreachable("Invalid Expression"); 193 194 const MCSymbolRefExpr *RefB = Value.getSymB(); 195 if (RefB) 196 Assembler.getContext().FatalError( 197 SMLoc(), Twine("symbol '") + RefB->getSymbol().getName() + 198 "' could not be evaluated in a subtraction expression"); 199 200 const MCSymbolRefExpr *A = Value.getSymA(); 201 if (!A) 202 return nullptr; 203 204 const MCSymbol &ASym = A->getSymbol(); 205 const MCAssembler &Asm = getAssembler(); 206 const MCSymbolData &ASD = Asm.getSymbolData(ASym); 207 if (ASD.isCommon()) { 208 // FIXME: we should probably add a SMLoc to MCExpr. 209 Asm.getContext().FatalError(SMLoc(), 210 "Common symbol " + ASym.getName() + 211 " cannot be used in assignment expr"); 212 } 213 214 return &ASym; 215 } 216 217 uint64_t MCAsmLayout::getSectionAddressSize(const MCSectionData *SD) const { 218 // The size is the last fragment's end offset. 219 const MCFragment &F = SD->getFragmentList().back(); 220 return getFragmentOffset(&F) + getAssembler().computeFragmentSize(*this, F); 221 } 222 223 uint64_t MCAsmLayout::getSectionFileSize(const MCSectionData *SD) const { 224 // Virtual sections have no file size. 225 if (SD->getSection().isVirtualSection()) 226 return 0; 227 228 // Otherwise, the file size is the same as the address space size. 229 return getSectionAddressSize(SD); 230 } 231 232 uint64_t llvm::computeBundlePadding(const MCAssembler &Assembler, 233 const MCFragment *F, 234 uint64_t FOffset, uint64_t FSize) { 235 uint64_t BundleSize = Assembler.getBundleAlignSize(); 236 assert(BundleSize > 0 && 237 "computeBundlePadding should only be called if bundling is enabled"); 238 uint64_t BundleMask = BundleSize - 1; 239 uint64_t OffsetInBundle = FOffset & BundleMask; 240 uint64_t EndOfFragment = OffsetInBundle + FSize; 241 242 // There are two kinds of bundling restrictions: 243 // 244 // 1) For alignToBundleEnd(), add padding to ensure that the fragment will 245 // *end* on a bundle boundary. 246 // 2) Otherwise, check if the fragment would cross a bundle boundary. If it 247 // would, add padding until the end of the bundle so that the fragment 248 // will start in a new one. 249 if (F->alignToBundleEnd()) { 250 // Three possibilities here: 251 // 252 // A) The fragment just happens to end at a bundle boundary, so we're good. 253 // B) The fragment ends before the current bundle boundary: pad it just 254 // enough to reach the boundary. 255 // C) The fragment ends after the current bundle boundary: pad it until it 256 // reaches the end of the next bundle boundary. 257 // 258 // Note: this code could be made shorter with some modulo trickery, but it's 259 // intentionally kept in its more explicit form for simplicity. 260 if (EndOfFragment == BundleSize) 261 return 0; 262 else if (EndOfFragment < BundleSize) 263 return BundleSize - EndOfFragment; 264 else { // EndOfFragment > BundleSize 265 return 2 * BundleSize - EndOfFragment; 266 } 267 } else if (EndOfFragment > BundleSize) 268 return BundleSize - OffsetInBundle; 269 else 270 return 0; 271 } 272 273 /* *** */ 274 275 MCFragment::MCFragment() : Kind(FragmentType(~0)) { 276 } 277 278 MCFragment::~MCFragment() { 279 } 280 281 MCFragment::MCFragment(FragmentType Kind, MCSectionData *Parent) 282 : Kind(Kind), Parent(Parent), Atom(nullptr), Offset(~UINT64_C(0)) { 283 if (Parent) 284 Parent->getFragmentList().push_back(this); 285 } 286 287 /* *** */ 288 289 MCEncodedFragment::~MCEncodedFragment() { 290 } 291 292 /* *** */ 293 294 MCEncodedFragmentWithFixups::~MCEncodedFragmentWithFixups() { 295 } 296 297 /* *** */ 298 299 MCSectionData::MCSectionData() : Section(nullptr) {} 300 301 MCSectionData::MCSectionData(const MCSection &Section, MCAssembler *A) 302 : Section(&Section), Ordinal(~UINT32_C(0)), Alignment(1), 303 BundleLockState(NotBundleLocked), BundleLockNestingDepth(0), 304 BundleGroupBeforeFirstInst(false), HasInstructions(false) { 305 if (A) 306 A->getSectionList().push_back(this); 307 } 308 309 MCSectionData::iterator 310 MCSectionData::getSubsectionInsertionPoint(unsigned Subsection) { 311 if (Subsection == 0 && SubsectionFragmentMap.empty()) 312 return end(); 313 314 SmallVectorImpl<std::pair<unsigned, MCFragment *> >::iterator MI = 315 std::lower_bound(SubsectionFragmentMap.begin(), SubsectionFragmentMap.end(), 316 std::make_pair(Subsection, (MCFragment *)nullptr)); 317 bool ExactMatch = false; 318 if (MI != SubsectionFragmentMap.end()) { 319 ExactMatch = MI->first == Subsection; 320 if (ExactMatch) 321 ++MI; 322 } 323 iterator IP; 324 if (MI == SubsectionFragmentMap.end()) 325 IP = end(); 326 else 327 IP = MI->second; 328 if (!ExactMatch && Subsection != 0) { 329 // The GNU as documentation claims that subsections have an alignment of 4, 330 // although this appears not to be the case. 331 MCFragment *F = new MCDataFragment(); 332 SubsectionFragmentMap.insert(MI, std::make_pair(Subsection, F)); 333 getFragmentList().insert(IP, F); 334 F->setParent(this); 335 } 336 337 return IP; 338 } 339 340 void MCSectionData::setBundleLockState(BundleLockStateType NewState) { 341 if (NewState == NotBundleLocked) { 342 if (BundleLockNestingDepth == 0) { 343 report_fatal_error("Mismatched bundle_lock/unlock directives"); 344 } 345 if (--BundleLockNestingDepth == 0) { 346 BundleLockState = NotBundleLocked; 347 } 348 return; 349 } 350 351 // If any of the directives is an align_to_end directive, the whole nested 352 // group is align_to_end. So don't downgrade from align_to_end to just locked. 353 if (BundleLockState != BundleLockedAlignToEnd) { 354 BundleLockState = NewState; 355 } 356 ++BundleLockNestingDepth; 357 } 358 359 /* *** */ 360 361 MCSymbolData::MCSymbolData() : Symbol(nullptr) {} 362 363 MCSymbolData::MCSymbolData(const MCSymbol &Symbol, MCFragment *Fragment, 364 uint64_t Offset, MCAssembler *A) 365 : Symbol(&Symbol), Fragment(Fragment), Offset(Offset), SymbolSize(nullptr), 366 CommonAlign(-1U), Flags(0), Index(0) { 367 if (A) 368 A->getSymbolList().push_back(this); 369 } 370 371 /* *** */ 372 373 MCAssembler::MCAssembler(MCContext &Context_, MCAsmBackend &Backend_, 374 MCCodeEmitter &Emitter_, MCObjectWriter &Writer_, 375 raw_ostream &OS_) 376 : Context(Context_), Backend(Backend_), Emitter(Emitter_), Writer(Writer_), 377 OS(OS_), BundleAlignSize(0), RelaxAll(false), 378 SubsectionsViaSymbols(false), ELFHeaderEFlags(0) { 379 VersionMinInfo.Major = 0; // Major version == 0 for "none specified" 380 } 381 382 MCAssembler::~MCAssembler() { 383 } 384 385 void MCAssembler::reset() { 386 Sections.clear(); 387 Symbols.clear(); 388 SectionMap.clear(); 389 SymbolMap.clear(); 390 IndirectSymbols.clear(); 391 DataRegions.clear(); 392 LinkerOptions.clear(); 393 FileNames.clear(); 394 ThumbFuncs.clear(); 395 BundleAlignSize = 0; 396 RelaxAll = false; 397 SubsectionsViaSymbols = false; 398 ELFHeaderEFlags = 0; 399 LOHContainer.reset(); 400 VersionMinInfo.Major = 0; 401 402 // reset objects owned by us 403 getBackend().reset(); 404 getEmitter().reset(); 405 getWriter().reset(); 406 getLOHContainer().reset(); 407 } 408 409 bool MCAssembler::isThumbFunc(const MCSymbol *Symbol) const { 410 if (ThumbFuncs.count(Symbol)) 411 return true; 412 413 if (!Symbol->isVariable()) 414 return false; 415 416 // FIXME: It looks like gas supports some cases of the form "foo + 2". It 417 // is not clear if that is a bug or a feature. 418 const MCExpr *Expr = Symbol->getVariableValue(); 419 const MCSymbolRefExpr *Ref = dyn_cast<MCSymbolRefExpr>(Expr); 420 if (!Ref) 421 return false; 422 423 if (Ref->getKind() != MCSymbolRefExpr::VK_None) 424 return false; 425 426 const MCSymbol &Sym = Ref->getSymbol(); 427 if (!isThumbFunc(&Sym)) 428 return false; 429 430 ThumbFuncs.insert(Symbol); // Cache it. 431 return true; 432 } 433 434 void MCAssembler::addLocalUsedInReloc(const MCSymbol &Sym) { 435 assert(Sym.isTemporary()); 436 LocalsUsedInReloc.insert(&Sym); 437 } 438 439 bool MCAssembler::isLocalUsedInReloc(const MCSymbol &Sym) const { 440 assert(Sym.isTemporary()); 441 return LocalsUsedInReloc.count(&Sym); 442 } 443 444 bool MCAssembler::isSymbolLinkerVisible(const MCSymbol &Symbol) const { 445 // Non-temporary labels should always be visible to the linker. 446 if (!Symbol.isTemporary()) 447 return true; 448 449 // Absolute temporary labels are never visible. 450 if (!Symbol.isInSection()) 451 return false; 452 453 if (isLocalUsedInReloc(Symbol)) 454 return true; 455 456 return false; 457 } 458 459 const MCSymbolData *MCAssembler::getAtom(const MCSymbolData *SD) const { 460 // Linker visible symbols define atoms. 461 if (isSymbolLinkerVisible(SD->getSymbol())) 462 return SD; 463 464 // Absolute and undefined symbols have no defining atom. 465 if (!SD->getFragment()) 466 return nullptr; 467 468 // Non-linker visible symbols in sections which can't be atomized have no 469 // defining atom. 470 if (!getContext().getAsmInfo()->isSectionAtomizableBySymbols( 471 SD->getFragment()->getParent()->getSection())) 472 return nullptr; 473 474 // Otherwise, return the atom for the containing fragment. 475 return SD->getFragment()->getAtom(); 476 } 477 478 bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout, 479 const MCFixup &Fixup, const MCFragment *DF, 480 MCValue &Target, uint64_t &Value) const { 481 ++stats::evaluateFixup; 482 483 // FIXME: This code has some duplication with RecordRelocation. We should 484 // probably merge the two into a single callback that tries to evaluate a 485 // fixup and records a relocation if one is needed. 486 const MCExpr *Expr = Fixup.getValue(); 487 if (!Expr->EvaluateAsRelocatable(Target, &Layout, &Fixup)) 488 getContext().FatalError(Fixup.getLoc(), "expected relocatable expression"); 489 490 bool IsPCRel = Backend.getFixupKindInfo( 491 Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel; 492 493 bool IsResolved; 494 if (IsPCRel) { 495 if (Target.getSymB()) { 496 IsResolved = false; 497 } else if (!Target.getSymA()) { 498 IsResolved = false; 499 } else { 500 const MCSymbolRefExpr *A = Target.getSymA(); 501 const MCSymbol &SA = A->getSymbol(); 502 if (A->getKind() != MCSymbolRefExpr::VK_None || SA.isUndefined()) { 503 IsResolved = false; 504 } else { 505 const MCSymbolData &DataA = getSymbolData(SA); 506 IsResolved = getWriter().IsSymbolRefDifferenceFullyResolvedImpl( 507 *this, DataA, nullptr, *DF, false, true); 508 } 509 } 510 } else { 511 IsResolved = Target.isAbsolute(); 512 } 513 514 Value = Target.getConstant(); 515 516 if (const MCSymbolRefExpr *A = Target.getSymA()) { 517 const MCSymbol &Sym = A->getSymbol(); 518 if (Sym.isDefined()) 519 Value += Layout.getSymbolOffset(&getSymbolData(Sym)); 520 } 521 if (const MCSymbolRefExpr *B = Target.getSymB()) { 522 const MCSymbol &Sym = B->getSymbol(); 523 if (Sym.isDefined()) 524 Value -= Layout.getSymbolOffset(&getSymbolData(Sym)); 525 } 526 527 528 bool ShouldAlignPC = Backend.getFixupKindInfo(Fixup.getKind()).Flags & 529 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits; 530 assert((ShouldAlignPC ? IsPCRel : true) && 531 "FKF_IsAlignedDownTo32Bits is only allowed on PC-relative fixups!"); 532 533 if (IsPCRel) { 534 uint32_t Offset = Layout.getFragmentOffset(DF) + Fixup.getOffset(); 535 536 // A number of ARM fixups in Thumb mode require that the effective PC 537 // address be determined as the 32-bit aligned version of the actual offset. 538 if (ShouldAlignPC) Offset &= ~0x3; 539 Value -= Offset; 540 } 541 542 // Let the backend adjust the fixup value if necessary, including whether 543 // we need a relocation. 544 Backend.processFixupValue(*this, Layout, Fixup, DF, Target, Value, 545 IsResolved); 546 547 return IsResolved; 548 } 549 550 uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout, 551 const MCFragment &F) const { 552 switch (F.getKind()) { 553 case MCFragment::FT_Data: 554 case MCFragment::FT_Relaxable: 555 case MCFragment::FT_CompactEncodedInst: 556 return cast<MCEncodedFragment>(F).getContents().size(); 557 case MCFragment::FT_Fill: 558 return cast<MCFillFragment>(F).getSize(); 559 560 case MCFragment::FT_LEB: 561 return cast<MCLEBFragment>(F).getContents().size(); 562 563 case MCFragment::FT_Align: { 564 const MCAlignFragment &AF = cast<MCAlignFragment>(F); 565 unsigned Offset = Layout.getFragmentOffset(&AF); 566 unsigned Size = OffsetToAlignment(Offset, AF.getAlignment()); 567 // If we are padding with nops, force the padding to be larger than the 568 // minimum nop size. 569 if (Size > 0 && AF.hasEmitNops()) { 570 while (Size % getBackend().getMinimumNopSize()) 571 Size += AF.getAlignment(); 572 } 573 if (Size > AF.getMaxBytesToEmit()) 574 return 0; 575 return Size; 576 } 577 578 case MCFragment::FT_Org: { 579 const MCOrgFragment &OF = cast<MCOrgFragment>(F); 580 int64_t TargetLocation; 581 if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, Layout)) 582 report_fatal_error("expected assembly-time absolute expression"); 583 584 // FIXME: We need a way to communicate this error. 585 uint64_t FragmentOffset = Layout.getFragmentOffset(&OF); 586 int64_t Size = TargetLocation - FragmentOffset; 587 if (Size < 0 || Size >= 0x40000000) 588 report_fatal_error("invalid .org offset '" + Twine(TargetLocation) + 589 "' (at offset '" + Twine(FragmentOffset) + "')"); 590 return Size; 591 } 592 593 case MCFragment::FT_Dwarf: 594 return cast<MCDwarfLineAddrFragment>(F).getContents().size(); 595 case MCFragment::FT_DwarfFrame: 596 return cast<MCDwarfCallFrameFragment>(F).getContents().size(); 597 } 598 599 llvm_unreachable("invalid fragment kind"); 600 } 601 602 void MCAsmLayout::layoutFragment(MCFragment *F) { 603 MCFragment *Prev = F->getPrevNode(); 604 605 // We should never try to recompute something which is valid. 606 assert(!isFragmentValid(F) && "Attempt to recompute a valid fragment!"); 607 // We should never try to compute the fragment layout if its predecessor 608 // isn't valid. 609 assert((!Prev || isFragmentValid(Prev)) && 610 "Attempt to compute fragment before its predecessor!"); 611 612 ++stats::FragmentLayouts; 613 614 // Compute fragment offset and size. 615 if (Prev) 616 F->Offset = Prev->Offset + getAssembler().computeFragmentSize(*this, *Prev); 617 else 618 F->Offset = 0; 619 LastValidFragment[F->getParent()] = F; 620 621 // If bundling is enabled and this fragment has instructions in it, it has to 622 // obey the bundling restrictions. With padding, we'll have: 623 // 624 // 625 // BundlePadding 626 // ||| 627 // ------------------------------------- 628 // Prev |##########| F | 629 // ------------------------------------- 630 // ^ 631 // | 632 // F->Offset 633 // 634 // The fragment's offset will point to after the padding, and its computed 635 // size won't include the padding. 636 // 637 // When the -mc-relax-all flag is used, we optimize bundling by writting the 638 // bundle padding directly into fragments when the instructions are emitted 639 // inside the streamer. 640 // 641 if (Assembler.isBundlingEnabled() && !Assembler.getRelaxAll() && 642 F->hasInstructions()) { 643 assert(isa<MCEncodedFragment>(F) && 644 "Only MCEncodedFragment implementations have instructions"); 645 uint64_t FSize = Assembler.computeFragmentSize(*this, *F); 646 647 if (FSize > Assembler.getBundleAlignSize()) 648 report_fatal_error("Fragment can't be larger than a bundle size"); 649 650 uint64_t RequiredBundlePadding = computeBundlePadding(Assembler, F, 651 F->Offset, FSize); 652 if (RequiredBundlePadding > UINT8_MAX) 653 report_fatal_error("Padding cannot exceed 255 bytes"); 654 F->setBundlePadding(static_cast<uint8_t>(RequiredBundlePadding)); 655 F->Offset += RequiredBundlePadding; 656 } 657 } 658 659 /// \brief Write the contents of a fragment to the given object writer. Expects 660 /// a MCEncodedFragment. 661 static void writeFragmentContents(const MCFragment &F, MCObjectWriter *OW) { 662 const MCEncodedFragment &EF = cast<MCEncodedFragment>(F); 663 OW->WriteBytes(EF.getContents()); 664 } 665 666 void MCAssembler::writeFragmentPadding(const MCFragment &F, uint64_t FSize, 667 MCObjectWriter *OW) const { 668 // Should NOP padding be written out before this fragment? 669 unsigned BundlePadding = F.getBundlePadding(); 670 if (BundlePadding > 0) { 671 assert(isBundlingEnabled() && 672 "Writing bundle padding with disabled bundling"); 673 assert(F.hasInstructions() && 674 "Writing bundle padding for a fragment without instructions"); 675 676 unsigned TotalLength = BundlePadding + static_cast<unsigned>(FSize); 677 if (F.alignToBundleEnd() && TotalLength > getBundleAlignSize()) { 678 // If the padding itself crosses a bundle boundary, it must be emitted 679 // in 2 pieces, since even nop instructions must not cross boundaries. 680 // v--------------v <- BundleAlignSize 681 // v---------v <- BundlePadding 682 // ---------------------------- 683 // | Prev |####|####| F | 684 // ---------------------------- 685 // ^-------------------^ <- TotalLength 686 unsigned DistanceToBoundary = TotalLength - getBundleAlignSize(); 687 if (!getBackend().writeNopData(DistanceToBoundary, OW)) 688 report_fatal_error("unable to write NOP sequence of " + 689 Twine(DistanceToBoundary) + " bytes"); 690 BundlePadding -= DistanceToBoundary; 691 } 692 if (!getBackend().writeNopData(BundlePadding, OW)) 693 report_fatal_error("unable to write NOP sequence of " + 694 Twine(BundlePadding) + " bytes"); 695 } 696 } 697 698 /// \brief Write the fragment \p F to the output file. 699 static void writeFragment(const MCAssembler &Asm, const MCAsmLayout &Layout, 700 const MCFragment &F) { 701 MCObjectWriter *OW = &Asm.getWriter(); 702 703 // FIXME: Embed in fragments instead? 704 uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F); 705 706 Asm.writeFragmentPadding(F, FragmentSize, OW); 707 708 // This variable (and its dummy usage) is to participate in the assert at 709 // the end of the function. 710 uint64_t Start = OW->getStream().tell(); 711 (void) Start; 712 713 ++stats::EmittedFragments; 714 715 switch (F.getKind()) { 716 case MCFragment::FT_Align: { 717 ++stats::EmittedAlignFragments; 718 const MCAlignFragment &AF = cast<MCAlignFragment>(F); 719 assert(AF.getValueSize() && "Invalid virtual align in concrete fragment!"); 720 721 uint64_t Count = FragmentSize / AF.getValueSize(); 722 723 // FIXME: This error shouldn't actually occur (the front end should emit 724 // multiple .align directives to enforce the semantics it wants), but is 725 // severe enough that we want to report it. How to handle this? 726 if (Count * AF.getValueSize() != FragmentSize) 727 report_fatal_error("undefined .align directive, value size '" + 728 Twine(AF.getValueSize()) + 729 "' is not a divisor of padding size '" + 730 Twine(FragmentSize) + "'"); 731 732 // See if we are aligning with nops, and if so do that first to try to fill 733 // the Count bytes. Then if that did not fill any bytes or there are any 734 // bytes left to fill use the Value and ValueSize to fill the rest. 735 // If we are aligning with nops, ask that target to emit the right data. 736 if (AF.hasEmitNops()) { 737 if (!Asm.getBackend().writeNopData(Count, OW)) 738 report_fatal_error("unable to write nop sequence of " + 739 Twine(Count) + " bytes"); 740 break; 741 } 742 743 // Otherwise, write out in multiples of the value size. 744 for (uint64_t i = 0; i != Count; ++i) { 745 switch (AF.getValueSize()) { 746 default: llvm_unreachable("Invalid size!"); 747 case 1: OW->Write8 (uint8_t (AF.getValue())); break; 748 case 2: OW->Write16(uint16_t(AF.getValue())); break; 749 case 4: OW->Write32(uint32_t(AF.getValue())); break; 750 case 8: OW->Write64(uint64_t(AF.getValue())); break; 751 } 752 } 753 break; 754 } 755 756 case MCFragment::FT_Data: 757 ++stats::EmittedDataFragments; 758 writeFragmentContents(F, OW); 759 break; 760 761 case MCFragment::FT_Relaxable: 762 ++stats::EmittedRelaxableFragments; 763 writeFragmentContents(F, OW); 764 break; 765 766 case MCFragment::FT_CompactEncodedInst: 767 ++stats::EmittedCompactEncodedInstFragments; 768 writeFragmentContents(F, OW); 769 break; 770 771 case MCFragment::FT_Fill: { 772 ++stats::EmittedFillFragments; 773 const MCFillFragment &FF = cast<MCFillFragment>(F); 774 775 assert(FF.getValueSize() && "Invalid virtual align in concrete fragment!"); 776 777 for (uint64_t i = 0, e = FF.getSize() / FF.getValueSize(); i != e; ++i) { 778 switch (FF.getValueSize()) { 779 default: llvm_unreachable("Invalid size!"); 780 case 1: OW->Write8 (uint8_t (FF.getValue())); break; 781 case 2: OW->Write16(uint16_t(FF.getValue())); break; 782 case 4: OW->Write32(uint32_t(FF.getValue())); break; 783 case 8: OW->Write64(uint64_t(FF.getValue())); break; 784 } 785 } 786 break; 787 } 788 789 case MCFragment::FT_LEB: { 790 const MCLEBFragment &LF = cast<MCLEBFragment>(F); 791 OW->WriteBytes(LF.getContents()); 792 break; 793 } 794 795 case MCFragment::FT_Org: { 796 ++stats::EmittedOrgFragments; 797 const MCOrgFragment &OF = cast<MCOrgFragment>(F); 798 799 for (uint64_t i = 0, e = FragmentSize; i != e; ++i) 800 OW->Write8(uint8_t(OF.getValue())); 801 802 break; 803 } 804 805 case MCFragment::FT_Dwarf: { 806 const MCDwarfLineAddrFragment &OF = cast<MCDwarfLineAddrFragment>(F); 807 OW->WriteBytes(OF.getContents()); 808 break; 809 } 810 case MCFragment::FT_DwarfFrame: { 811 const MCDwarfCallFrameFragment &CF = cast<MCDwarfCallFrameFragment>(F); 812 OW->WriteBytes(CF.getContents()); 813 break; 814 } 815 } 816 817 assert(OW->getStream().tell() - Start == FragmentSize && 818 "The stream should advance by fragment size"); 819 } 820 821 void MCAssembler::writeSectionData(const MCSectionData *SD, 822 const MCAsmLayout &Layout) const { 823 // Ignore virtual sections. 824 if (SD->getSection().isVirtualSection()) { 825 assert(Layout.getSectionFileSize(SD) == 0 && "Invalid size for section!"); 826 827 // Check that contents are only things legal inside a virtual section. 828 for (MCSectionData::const_iterator it = SD->begin(), 829 ie = SD->end(); it != ie; ++it) { 830 switch (it->getKind()) { 831 default: llvm_unreachable("Invalid fragment in virtual section!"); 832 case MCFragment::FT_Data: { 833 // Check that we aren't trying to write a non-zero contents (or fixups) 834 // into a virtual section. This is to support clients which use standard 835 // directives to fill the contents of virtual sections. 836 const MCDataFragment &DF = cast<MCDataFragment>(*it); 837 assert(DF.fixup_begin() == DF.fixup_end() && 838 "Cannot have fixups in virtual section!"); 839 for (unsigned i = 0, e = DF.getContents().size(); i != e; ++i) 840 if (DF.getContents()[i]) { 841 if (auto *ELFSec = dyn_cast<const MCSectionELF>(&SD->getSection())) 842 report_fatal_error("non-zero initializer found in section '" + 843 ELFSec->getSectionName() + "'"); 844 else 845 report_fatal_error("non-zero initializer found in virtual section"); 846 } 847 break; 848 } 849 case MCFragment::FT_Align: 850 // Check that we aren't trying to write a non-zero value into a virtual 851 // section. 852 assert((cast<MCAlignFragment>(it)->getValueSize() == 0 || 853 cast<MCAlignFragment>(it)->getValue() == 0) && 854 "Invalid align in virtual section!"); 855 break; 856 case MCFragment::FT_Fill: 857 assert((cast<MCFillFragment>(it)->getValueSize() == 0 || 858 cast<MCFillFragment>(it)->getValue() == 0) && 859 "Invalid fill in virtual section!"); 860 break; 861 } 862 } 863 864 return; 865 } 866 867 uint64_t Start = getWriter().getStream().tell(); 868 (void)Start; 869 870 for (MCSectionData::const_iterator it = SD->begin(), ie = SD->end(); 871 it != ie; ++it) 872 writeFragment(*this, Layout, *it); 873 874 assert(getWriter().getStream().tell() - Start == 875 Layout.getSectionAddressSize(SD)); 876 } 877 878 std::pair<uint64_t, bool> MCAssembler::handleFixup(const MCAsmLayout &Layout, 879 MCFragment &F, 880 const MCFixup &Fixup) { 881 // Evaluate the fixup. 882 MCValue Target; 883 uint64_t FixedValue; 884 bool IsPCRel = Backend.getFixupKindInfo(Fixup.getKind()).Flags & 885 MCFixupKindInfo::FKF_IsPCRel; 886 if (!evaluateFixup(Layout, Fixup, &F, Target, FixedValue)) { 887 // The fixup was unresolved, we need a relocation. Inform the object 888 // writer of the relocation, and give it an opportunity to adjust the 889 // fixup value if need be. 890 getWriter().RecordRelocation(*this, Layout, &F, Fixup, Target, IsPCRel, 891 FixedValue); 892 } 893 return std::make_pair(FixedValue, IsPCRel); 894 } 895 896 void MCAssembler::Finish() { 897 DEBUG_WITH_TYPE("mc-dump", { 898 llvm::errs() << "assembler backend - pre-layout\n--\n"; 899 dump(); }); 900 901 // Create the layout object. 902 MCAsmLayout Layout(*this); 903 904 // Create dummy fragments and assign section ordinals. 905 unsigned SectionIndex = 0; 906 for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { 907 // Create dummy fragments to eliminate any empty sections, this simplifies 908 // layout. 909 if (it->getFragmentList().empty()) 910 new MCDataFragment(it); 911 912 it->setOrdinal(SectionIndex++); 913 } 914 915 // Assign layout order indices to sections and fragments. 916 for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) { 917 MCSectionData *SD = Layout.getSectionOrder()[i]; 918 SD->setLayoutOrder(i); 919 920 unsigned FragmentIndex = 0; 921 for (MCSectionData::iterator iFrag = SD->begin(), iFragEnd = SD->end(); 922 iFrag != iFragEnd; ++iFrag) 923 iFrag->setLayoutOrder(FragmentIndex++); 924 } 925 926 // Layout until everything fits. 927 while (layoutOnce(Layout)) 928 continue; 929 930 DEBUG_WITH_TYPE("mc-dump", { 931 llvm::errs() << "assembler backend - post-relaxation\n--\n"; 932 dump(); }); 933 934 // Finalize the layout, including fragment lowering. 935 finishLayout(Layout); 936 937 DEBUG_WITH_TYPE("mc-dump", { 938 llvm::errs() << "assembler backend - final-layout\n--\n"; 939 dump(); }); 940 941 uint64_t StartOffset = OS.tell(); 942 943 // Allow the object writer a chance to perform post-layout binding (for 944 // example, to set the index fields in the symbol data). 945 getWriter().ExecutePostLayoutBinding(*this, Layout); 946 947 // Evaluate and apply the fixups, generating relocation entries as necessary. 948 for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { 949 for (MCSectionData::iterator it2 = it->begin(), 950 ie2 = it->end(); it2 != ie2; ++it2) { 951 MCEncodedFragmentWithFixups *F = 952 dyn_cast<MCEncodedFragmentWithFixups>(it2); 953 if (F) { 954 for (MCEncodedFragmentWithFixups::fixup_iterator it3 = F->fixup_begin(), 955 ie3 = F->fixup_end(); it3 != ie3; ++it3) { 956 MCFixup &Fixup = *it3; 957 uint64_t FixedValue; 958 bool IsPCRel; 959 std::tie(FixedValue, IsPCRel) = handleFixup(Layout, *F, Fixup); 960 getBackend().applyFixup(Fixup, F->getContents().data(), 961 F->getContents().size(), FixedValue, IsPCRel); 962 } 963 } 964 } 965 } 966 967 // Write the object file. 968 getWriter().WriteObject(*this, Layout); 969 970 stats::ObjectBytes += OS.tell() - StartOffset; 971 } 972 973 bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup, 974 const MCRelaxableFragment *DF, 975 const MCAsmLayout &Layout) const { 976 // If we cannot resolve the fixup value, it requires relaxation. 977 MCValue Target; 978 uint64_t Value; 979 if (!evaluateFixup(Layout, Fixup, DF, Target, Value)) 980 return true; 981 982 return getBackend().fixupNeedsRelaxation(Fixup, Value, DF, Layout); 983 } 984 985 bool MCAssembler::fragmentNeedsRelaxation(const MCRelaxableFragment *F, 986 const MCAsmLayout &Layout) const { 987 // If this inst doesn't ever need relaxation, ignore it. This occurs when we 988 // are intentionally pushing out inst fragments, or because we relaxed a 989 // previous instruction to one that doesn't need relaxation. 990 if (!getBackend().mayNeedRelaxation(F->getInst())) 991 return false; 992 993 for (MCRelaxableFragment::const_fixup_iterator it = F->fixup_begin(), 994 ie = F->fixup_end(); it != ie; ++it) 995 if (fixupNeedsRelaxation(*it, F, Layout)) 996 return true; 997 998 return false; 999 } 1000 1001 bool MCAssembler::relaxInstruction(MCAsmLayout &Layout, 1002 MCRelaxableFragment &F) { 1003 if (!fragmentNeedsRelaxation(&F, Layout)) 1004 return false; 1005 1006 ++stats::RelaxedInstructions; 1007 1008 // FIXME-PERF: We could immediately lower out instructions if we can tell 1009 // they are fully resolved, to avoid retesting on later passes. 1010 1011 // Relax the fragment. 1012 1013 MCInst Relaxed; 1014 getBackend().relaxInstruction(F.getInst(), Relaxed); 1015 1016 // Encode the new instruction. 1017 // 1018 // FIXME-PERF: If it matters, we could let the target do this. It can 1019 // probably do so more efficiently in many cases. 1020 SmallVector<MCFixup, 4> Fixups; 1021 SmallString<256> Code; 1022 raw_svector_ostream VecOS(Code); 1023 getEmitter().EncodeInstruction(Relaxed, VecOS, Fixups, F.getSubtargetInfo()); 1024 VecOS.flush(); 1025 1026 // Update the fragment. 1027 F.setInst(Relaxed); 1028 F.getContents() = Code; 1029 F.getFixups() = Fixups; 1030 1031 return true; 1032 } 1033 1034 bool MCAssembler::relaxLEB(MCAsmLayout &Layout, MCLEBFragment &LF) { 1035 uint64_t OldSize = LF.getContents().size(); 1036 int64_t Value; 1037 bool Abs = LF.getValue().evaluateKnownAbsolute(Value, Layout); 1038 if (!Abs) 1039 report_fatal_error("sleb128 and uleb128 expressions must be absolute"); 1040 SmallString<8> &Data = LF.getContents(); 1041 Data.clear(); 1042 raw_svector_ostream OSE(Data); 1043 if (LF.isSigned()) 1044 encodeSLEB128(Value, OSE); 1045 else 1046 encodeULEB128(Value, OSE); 1047 OSE.flush(); 1048 return OldSize != LF.getContents().size(); 1049 } 1050 1051 bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout, 1052 MCDwarfLineAddrFragment &DF) { 1053 MCContext &Context = Layout.getAssembler().getContext(); 1054 uint64_t OldSize = DF.getContents().size(); 1055 int64_t AddrDelta; 1056 bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout); 1057 assert(Abs && "We created a line delta with an invalid expression"); 1058 (void) Abs; 1059 int64_t LineDelta; 1060 LineDelta = DF.getLineDelta(); 1061 SmallString<8> &Data = DF.getContents(); 1062 Data.clear(); 1063 raw_svector_ostream OSE(Data); 1064 MCDwarfLineAddr::Encode(Context, LineDelta, AddrDelta, OSE); 1065 OSE.flush(); 1066 return OldSize != Data.size(); 1067 } 1068 1069 bool MCAssembler::relaxDwarfCallFrameFragment(MCAsmLayout &Layout, 1070 MCDwarfCallFrameFragment &DF) { 1071 MCContext &Context = Layout.getAssembler().getContext(); 1072 uint64_t OldSize = DF.getContents().size(); 1073 int64_t AddrDelta; 1074 bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout); 1075 assert(Abs && "We created call frame with an invalid expression"); 1076 (void) Abs; 1077 SmallString<8> &Data = DF.getContents(); 1078 Data.clear(); 1079 raw_svector_ostream OSE(Data); 1080 MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE); 1081 OSE.flush(); 1082 return OldSize != Data.size(); 1083 } 1084 1085 bool MCAssembler::layoutSectionOnce(MCAsmLayout &Layout, MCSectionData &SD) { 1086 // Holds the first fragment which needed relaxing during this layout. It will 1087 // remain NULL if none were relaxed. 1088 // When a fragment is relaxed, all the fragments following it should get 1089 // invalidated because their offset is going to change. 1090 MCFragment *FirstRelaxedFragment = nullptr; 1091 1092 // Attempt to relax all the fragments in the section. 1093 for (MCSectionData::iterator I = SD.begin(), IE = SD.end(); I != IE; ++I) { 1094 // Check if this is a fragment that needs relaxation. 1095 bool RelaxedFrag = false; 1096 switch(I->getKind()) { 1097 default: 1098 break; 1099 case MCFragment::FT_Relaxable: 1100 assert(!getRelaxAll() && 1101 "Did not expect a MCRelaxableFragment in RelaxAll mode"); 1102 RelaxedFrag = relaxInstruction(Layout, *cast<MCRelaxableFragment>(I)); 1103 break; 1104 case MCFragment::FT_Dwarf: 1105 RelaxedFrag = relaxDwarfLineAddr(Layout, 1106 *cast<MCDwarfLineAddrFragment>(I)); 1107 break; 1108 case MCFragment::FT_DwarfFrame: 1109 RelaxedFrag = 1110 relaxDwarfCallFrameFragment(Layout, 1111 *cast<MCDwarfCallFrameFragment>(I)); 1112 break; 1113 case MCFragment::FT_LEB: 1114 RelaxedFrag = relaxLEB(Layout, *cast<MCLEBFragment>(I)); 1115 break; 1116 } 1117 if (RelaxedFrag && !FirstRelaxedFragment) 1118 FirstRelaxedFragment = I; 1119 } 1120 if (FirstRelaxedFragment) { 1121 Layout.invalidateFragmentsFrom(FirstRelaxedFragment); 1122 return true; 1123 } 1124 return false; 1125 } 1126 1127 bool MCAssembler::layoutOnce(MCAsmLayout &Layout) { 1128 ++stats::RelaxationSteps; 1129 1130 bool WasRelaxed = false; 1131 for (iterator it = begin(), ie = end(); it != ie; ++it) { 1132 MCSectionData &SD = *it; 1133 while (layoutSectionOnce(Layout, SD)) 1134 WasRelaxed = true; 1135 } 1136 1137 return WasRelaxed; 1138 } 1139 1140 void MCAssembler::finishLayout(MCAsmLayout &Layout) { 1141 // The layout is done. Mark every fragment as valid. 1142 for (unsigned int i = 0, n = Layout.getSectionOrder().size(); i != n; ++i) { 1143 Layout.getFragmentOffset(&*Layout.getSectionOrder()[i]->rbegin()); 1144 } 1145 } 1146 1147 // Debugging methods 1148 1149 namespace llvm { 1150 1151 raw_ostream &operator<<(raw_ostream &OS, const MCFixup &AF) { 1152 OS << "<MCFixup" << " Offset:" << AF.getOffset() 1153 << " Value:" << *AF.getValue() 1154 << " Kind:" << AF.getKind() << ">"; 1155 return OS; 1156 } 1157 1158 } 1159 1160 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 1161 void MCFragment::dump() { 1162 raw_ostream &OS = llvm::errs(); 1163 1164 OS << "<"; 1165 switch (getKind()) { 1166 case MCFragment::FT_Align: OS << "MCAlignFragment"; break; 1167 case MCFragment::FT_Data: OS << "MCDataFragment"; break; 1168 case MCFragment::FT_CompactEncodedInst: 1169 OS << "MCCompactEncodedInstFragment"; break; 1170 case MCFragment::FT_Fill: OS << "MCFillFragment"; break; 1171 case MCFragment::FT_Relaxable: OS << "MCRelaxableFragment"; break; 1172 case MCFragment::FT_Org: OS << "MCOrgFragment"; break; 1173 case MCFragment::FT_Dwarf: OS << "MCDwarfFragment"; break; 1174 case MCFragment::FT_DwarfFrame: OS << "MCDwarfCallFrameFragment"; break; 1175 case MCFragment::FT_LEB: OS << "MCLEBFragment"; break; 1176 } 1177 1178 OS << "<MCFragment " << (void*) this << " LayoutOrder:" << LayoutOrder 1179 << " Offset:" << Offset 1180 << " HasInstructions:" << hasInstructions() 1181 << " BundlePadding:" << static_cast<unsigned>(getBundlePadding()) << ">"; 1182 1183 switch (getKind()) { 1184 case MCFragment::FT_Align: { 1185 const MCAlignFragment *AF = cast<MCAlignFragment>(this); 1186 if (AF->hasEmitNops()) 1187 OS << " (emit nops)"; 1188 OS << "\n "; 1189 OS << " Alignment:" << AF->getAlignment() 1190 << " Value:" << AF->getValue() << " ValueSize:" << AF->getValueSize() 1191 << " MaxBytesToEmit:" << AF->getMaxBytesToEmit() << ">"; 1192 break; 1193 } 1194 case MCFragment::FT_Data: { 1195 const MCDataFragment *DF = cast<MCDataFragment>(this); 1196 OS << "\n "; 1197 OS << " Contents:["; 1198 const SmallVectorImpl<char> &Contents = DF->getContents(); 1199 for (unsigned i = 0, e = Contents.size(); i != e; ++i) { 1200 if (i) OS << ","; 1201 OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); 1202 } 1203 OS << "] (" << Contents.size() << " bytes)"; 1204 1205 if (DF->fixup_begin() != DF->fixup_end()) { 1206 OS << ",\n "; 1207 OS << " Fixups:["; 1208 for (MCDataFragment::const_fixup_iterator it = DF->fixup_begin(), 1209 ie = DF->fixup_end(); it != ie; ++it) { 1210 if (it != DF->fixup_begin()) OS << ",\n "; 1211 OS << *it; 1212 } 1213 OS << "]"; 1214 } 1215 break; 1216 } 1217 case MCFragment::FT_CompactEncodedInst: { 1218 const MCCompactEncodedInstFragment *CEIF = 1219 cast<MCCompactEncodedInstFragment>(this); 1220 OS << "\n "; 1221 OS << " Contents:["; 1222 const SmallVectorImpl<char> &Contents = CEIF->getContents(); 1223 for (unsigned i = 0, e = Contents.size(); i != e; ++i) { 1224 if (i) OS << ","; 1225 OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); 1226 } 1227 OS << "] (" << Contents.size() << " bytes)"; 1228 break; 1229 } 1230 case MCFragment::FT_Fill: { 1231 const MCFillFragment *FF = cast<MCFillFragment>(this); 1232 OS << " Value:" << FF->getValue() << " ValueSize:" << FF->getValueSize() 1233 << " Size:" << FF->getSize(); 1234 break; 1235 } 1236 case MCFragment::FT_Relaxable: { 1237 const MCRelaxableFragment *F = cast<MCRelaxableFragment>(this); 1238 OS << "\n "; 1239 OS << " Inst:"; 1240 F->getInst().dump_pretty(OS); 1241 break; 1242 } 1243 case MCFragment::FT_Org: { 1244 const MCOrgFragment *OF = cast<MCOrgFragment>(this); 1245 OS << "\n "; 1246 OS << " Offset:" << OF->getOffset() << " Value:" << OF->getValue(); 1247 break; 1248 } 1249 case MCFragment::FT_Dwarf: { 1250 const MCDwarfLineAddrFragment *OF = cast<MCDwarfLineAddrFragment>(this); 1251 OS << "\n "; 1252 OS << " AddrDelta:" << OF->getAddrDelta() 1253 << " LineDelta:" << OF->getLineDelta(); 1254 break; 1255 } 1256 case MCFragment::FT_DwarfFrame: { 1257 const MCDwarfCallFrameFragment *CF = cast<MCDwarfCallFrameFragment>(this); 1258 OS << "\n "; 1259 OS << " AddrDelta:" << CF->getAddrDelta(); 1260 break; 1261 } 1262 case MCFragment::FT_LEB: { 1263 const MCLEBFragment *LF = cast<MCLEBFragment>(this); 1264 OS << "\n "; 1265 OS << " Value:" << LF->getValue() << " Signed:" << LF->isSigned(); 1266 break; 1267 } 1268 } 1269 OS << ">"; 1270 } 1271 1272 void MCSectionData::dump() { 1273 raw_ostream &OS = llvm::errs(); 1274 1275 OS << "<MCSectionData"; 1276 OS << " Alignment:" << getAlignment() 1277 << " Fragments:[\n "; 1278 for (iterator it = begin(), ie = end(); it != ie; ++it) { 1279 if (it != begin()) OS << ",\n "; 1280 it->dump(); 1281 } 1282 OS << "]>"; 1283 } 1284 1285 void MCSymbolData::dump() const { 1286 raw_ostream &OS = llvm::errs(); 1287 1288 OS << "<MCSymbolData Symbol:" << getSymbol() 1289 << " Fragment:" << getFragment(); 1290 if (!isCommon()) 1291 OS << " Offset:" << getOffset(); 1292 OS << " Flags:" << getFlags() << " Index:" << getIndex(); 1293 if (isCommon()) 1294 OS << " (common, size:" << getCommonSize() 1295 << " align: " << getCommonAlignment() << ")"; 1296 if (isExternal()) 1297 OS << " (external)"; 1298 if (isPrivateExtern()) 1299 OS << " (private extern)"; 1300 OS << ">"; 1301 } 1302 1303 void MCAssembler::dump() { 1304 raw_ostream &OS = llvm::errs(); 1305 1306 OS << "<MCAssembler\n"; 1307 OS << " Sections:[\n "; 1308 for (iterator it = begin(), ie = end(); it != ie; ++it) { 1309 if (it != begin()) OS << ",\n "; 1310 it->dump(); 1311 } 1312 OS << "],\n"; 1313 OS << " Symbols:["; 1314 1315 for (symbol_iterator it = symbol_begin(), ie = symbol_end(); it != ie; ++it) { 1316 if (it != symbol_begin()) OS << ",\n "; 1317 it->dump(); 1318 } 1319 OS << "]>\n"; 1320 } 1321 #endif 1322 1323 // anchors for MC*Fragment vtables 1324 void MCEncodedFragment::anchor() { } 1325 void MCEncodedFragmentWithFixups::anchor() { } 1326 void MCDataFragment::anchor() { } 1327 void MCCompactEncodedInstFragment::anchor() { } 1328 void MCRelaxableFragment::anchor() { } 1329 void MCAlignFragment::anchor() { } 1330 void MCFillFragment::anchor() { } 1331 void MCOrgFragment::anchor() { } 1332 void MCLEBFragment::anchor() { } 1333 void MCDwarfLineAddrFragment::anchor() { } 1334 void MCDwarfCallFrameFragment::anchor() { } 1335