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 (MCSection &Sec : Asm) 72 if (!Sec.isVirtualSection()) 73 SectionOrder.push_back(&Sec); 74 for (MCSection &Sec : Asm) 75 if (Sec.isVirtualSection()) 76 SectionOrder.push_back(&Sec); 77 } 78 79 bool MCAsmLayout::isFragmentValid(const MCFragment *F) const { 80 const MCSection *Sec = F->getParent(); 81 const MCFragment *LastValid = LastValidFragment.lookup(Sec); 82 if (!LastValid) 83 return false; 84 assert(LastValid->getParent() == Sec); 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 LastValidFragment[F->getParent()] = F->getPrevNode(); 96 } 97 98 void MCAsmLayout::ensureValid(const MCFragment *F) const { 99 MCSection *Sec = F->getParent(); 100 MCSection::iterator I; 101 if (MCFragment *Cur = LastValidFragment[Sec]) 102 I = ++MCSection::iterator(Cur); 103 else 104 I = Sec->begin(); 105 106 // Advance the layout position until the fragment is valid. 107 while (!isFragmentValid(F)) { 108 assert(I != Sec->end() && "Layout bookkeeping error"); 109 const_cast<MCAsmLayout *>(this)->layoutFragment(&*I); 110 ++I; 111 } 112 } 113 114 uint64_t MCAsmLayout::getFragmentOffset(const MCFragment *F) const { 115 ensureValid(F); 116 assert(F->Offset != ~UINT64_C(0) && "Address not set!"); 117 return F->Offset; 118 } 119 120 // Simple getSymbolOffset helper for the non-varibale case. 121 static bool getLabelOffset(const MCAsmLayout &Layout, const MCSymbol &S, 122 bool ReportError, uint64_t &Val) { 123 if (!S.getFragment()) { 124 if (ReportError) 125 report_fatal_error("unable to evaluate offset to undefined symbol '" + 126 S.getName() + "'"); 127 return false; 128 } 129 Val = Layout.getFragmentOffset(S.getFragment()) + S.getOffset(); 130 return true; 131 } 132 133 static bool getSymbolOffsetImpl(const MCAsmLayout &Layout, const MCSymbol &S, 134 bool ReportError, uint64_t &Val) { 135 if (!S.isVariable()) 136 return getLabelOffset(Layout, S, ReportError, Val); 137 138 // If SD is a variable, evaluate it. 139 MCValue Target; 140 if (!S.getVariableValue()->evaluateAsValue(Target, Layout)) 141 report_fatal_error("unable to evaluate offset for variable '" + 142 S.getName() + "'"); 143 144 uint64_t Offset = Target.getConstant(); 145 146 const MCSymbolRefExpr *A = Target.getSymA(); 147 if (A) { 148 uint64_t ValA; 149 if (!getLabelOffset(Layout, A->getSymbol(), ReportError, ValA)) 150 return false; 151 Offset += ValA; 152 } 153 154 const MCSymbolRefExpr *B = Target.getSymB(); 155 if (B) { 156 uint64_t ValB; 157 if (!getLabelOffset(Layout, B->getSymbol(), ReportError, ValB)) 158 return false; 159 Offset -= ValB; 160 } 161 162 Val = Offset; 163 return true; 164 } 165 166 bool MCAsmLayout::getSymbolOffset(const MCSymbol &S, uint64_t &Val) const { 167 return getSymbolOffsetImpl(*this, S, false, Val); 168 } 169 170 uint64_t MCAsmLayout::getSymbolOffset(const MCSymbol &S) const { 171 uint64_t Val; 172 getSymbolOffsetImpl(*this, S, true, Val); 173 return Val; 174 } 175 176 const MCSymbol *MCAsmLayout::getBaseSymbol(const MCSymbol &Symbol) const { 177 if (!Symbol.isVariable()) 178 return &Symbol; 179 180 const MCExpr *Expr = Symbol.getVariableValue(); 181 MCValue Value; 182 if (!Expr->evaluateAsValue(Value, *this)) { 183 Assembler.getContext().reportError( 184 SMLoc(), "expression could not be evaluated"); 185 return nullptr; 186 } 187 188 const MCSymbolRefExpr *RefB = Value.getSymB(); 189 if (RefB) { 190 Assembler.getContext().reportError( 191 SMLoc(), Twine("symbol '") + RefB->getSymbol().getName() + 192 "' could not be evaluated in a subtraction expression"); 193 return nullptr; 194 } 195 196 const MCSymbolRefExpr *A = Value.getSymA(); 197 if (!A) 198 return nullptr; 199 200 const MCSymbol &ASym = A->getSymbol(); 201 const MCAssembler &Asm = getAssembler(); 202 if (ASym.isCommon()) { 203 // FIXME: we should probably add a SMLoc to MCExpr. 204 Asm.getContext().reportError(SMLoc(), 205 "Common symbol '" + ASym.getName() + 206 "' cannot be used in assignment expr"); 207 return nullptr; 208 } 209 210 return &ASym; 211 } 212 213 uint64_t MCAsmLayout::getSectionAddressSize(const MCSection *Sec) const { 214 // The size is the last fragment's end offset. 215 const MCFragment &F = Sec->getFragmentList().back(); 216 return getFragmentOffset(&F) + getAssembler().computeFragmentSize(*this, F); 217 } 218 219 uint64_t MCAsmLayout::getSectionFileSize(const MCSection *Sec) const { 220 // Virtual sections have no file size. 221 if (Sec->isVirtualSection()) 222 return 0; 223 224 // Otherwise, the file size is the same as the address space size. 225 return getSectionAddressSize(Sec); 226 } 227 228 uint64_t llvm::computeBundlePadding(const MCAssembler &Assembler, 229 const MCFragment *F, 230 uint64_t FOffset, uint64_t FSize) { 231 uint64_t BundleSize = Assembler.getBundleAlignSize(); 232 assert(BundleSize > 0 && 233 "computeBundlePadding should only be called if bundling is enabled"); 234 uint64_t BundleMask = BundleSize - 1; 235 uint64_t OffsetInBundle = FOffset & BundleMask; 236 uint64_t EndOfFragment = OffsetInBundle + FSize; 237 238 // There are two kinds of bundling restrictions: 239 // 240 // 1) For alignToBundleEnd(), add padding to ensure that the fragment will 241 // *end* on a bundle boundary. 242 // 2) Otherwise, check if the fragment would cross a bundle boundary. If it 243 // would, add padding until the end of the bundle so that the fragment 244 // will start in a new one. 245 if (F->alignToBundleEnd()) { 246 // Three possibilities here: 247 // 248 // A) The fragment just happens to end at a bundle boundary, so we're good. 249 // B) The fragment ends before the current bundle boundary: pad it just 250 // enough to reach the boundary. 251 // C) The fragment ends after the current bundle boundary: pad it until it 252 // reaches the end of the next bundle boundary. 253 // 254 // Note: this code could be made shorter with some modulo trickery, but it's 255 // intentionally kept in its more explicit form for simplicity. 256 if (EndOfFragment == BundleSize) 257 return 0; 258 else if (EndOfFragment < BundleSize) 259 return BundleSize - EndOfFragment; 260 else { // EndOfFragment > BundleSize 261 return 2 * BundleSize - EndOfFragment; 262 } 263 } else if (OffsetInBundle > 0 && EndOfFragment > BundleSize) 264 return BundleSize - OffsetInBundle; 265 else 266 return 0; 267 } 268 269 /* *** */ 270 271 void ilist_node_traits<MCFragment>::deleteNode(MCFragment *V) { 272 V->destroy(); 273 } 274 275 MCFragment::MCFragment() : Kind(FragmentType(~0)), HasInstructions(false), 276 AlignToBundleEnd(false), BundlePadding(0) { 277 } 278 279 MCFragment::~MCFragment() { } 280 281 MCFragment::MCFragment(FragmentType Kind, bool HasInstructions, 282 uint8_t BundlePadding, MCSection *Parent) 283 : Kind(Kind), HasInstructions(HasInstructions), AlignToBundleEnd(false), 284 BundlePadding(BundlePadding), Parent(Parent), Atom(nullptr), 285 Offset(~UINT64_C(0)) { 286 if (Parent && !isDummy()) 287 Parent->getFragmentList().push_back(this); 288 } 289 290 void MCFragment::destroy() { 291 // First check if we are the sentinal. 292 if (Kind == FragmentType(~0)) { 293 delete this; 294 return; 295 } 296 297 switch (Kind) { 298 case FT_Align: 299 delete cast<MCAlignFragment>(this); 300 return; 301 case FT_Data: 302 delete cast<MCDataFragment>(this); 303 return; 304 case FT_CompactEncodedInst: 305 delete cast<MCCompactEncodedInstFragment>(this); 306 return; 307 case FT_Fill: 308 delete cast<MCFillFragment>(this); 309 return; 310 case FT_Relaxable: 311 delete cast<MCRelaxableFragment>(this); 312 return; 313 case FT_Org: 314 delete cast<MCOrgFragment>(this); 315 return; 316 case FT_Dwarf: 317 delete cast<MCDwarfLineAddrFragment>(this); 318 return; 319 case FT_DwarfFrame: 320 delete cast<MCDwarfCallFrameFragment>(this); 321 return; 322 case FT_LEB: 323 delete cast<MCLEBFragment>(this); 324 return; 325 case FT_SafeSEH: 326 delete cast<MCSafeSEHFragment>(this); 327 return; 328 case FT_Dummy: 329 delete cast<MCDummyFragment>(this); 330 return; 331 } 332 } 333 334 /* *** */ 335 336 MCAssembler::MCAssembler(MCContext &Context_, MCAsmBackend &Backend_, 337 MCCodeEmitter &Emitter_, MCObjectWriter &Writer_) 338 : Context(Context_), Backend(Backend_), Emitter(Emitter_), Writer(Writer_), 339 BundleAlignSize(0), RelaxAll(false), SubsectionsViaSymbols(false), 340 IncrementalLinkerCompatible(false), ELFHeaderEFlags(0) { 341 VersionMinInfo.Major = 0; // Major version == 0 for "none specified" 342 } 343 344 MCAssembler::~MCAssembler() { 345 } 346 347 void MCAssembler::reset() { 348 Sections.clear(); 349 Symbols.clear(); 350 IndirectSymbols.clear(); 351 DataRegions.clear(); 352 LinkerOptions.clear(); 353 FileNames.clear(); 354 ThumbFuncs.clear(); 355 BundleAlignSize = 0; 356 RelaxAll = false; 357 SubsectionsViaSymbols = false; 358 IncrementalLinkerCompatible = false; 359 ELFHeaderEFlags = 0; 360 LOHContainer.reset(); 361 VersionMinInfo.Major = 0; 362 363 // reset objects owned by us 364 getBackend().reset(); 365 getEmitter().reset(); 366 getWriter().reset(); 367 getLOHContainer().reset(); 368 } 369 370 bool MCAssembler::registerSection(MCSection &Section) { 371 if (Section.isRegistered()) 372 return false; 373 Sections.push_back(&Section); 374 Section.setIsRegistered(true); 375 return true; 376 } 377 378 bool MCAssembler::isThumbFunc(const MCSymbol *Symbol) const { 379 if (ThumbFuncs.count(Symbol)) 380 return true; 381 382 if (!Symbol->isVariable()) 383 return false; 384 385 // FIXME: It looks like gas supports some cases of the form "foo + 2". It 386 // is not clear if that is a bug or a feature. 387 const MCExpr *Expr = Symbol->getVariableValue(); 388 const MCSymbolRefExpr *Ref = dyn_cast<MCSymbolRefExpr>(Expr); 389 if (!Ref) 390 return false; 391 392 if (Ref->getKind() != MCSymbolRefExpr::VK_None) 393 return false; 394 395 const MCSymbol &Sym = Ref->getSymbol(); 396 if (!isThumbFunc(&Sym)) 397 return false; 398 399 ThumbFuncs.insert(Symbol); // Cache it. 400 return true; 401 } 402 403 bool MCAssembler::isSymbolLinkerVisible(const MCSymbol &Symbol) const { 404 // Non-temporary labels should always be visible to the linker. 405 if (!Symbol.isTemporary()) 406 return true; 407 408 // Absolute temporary labels are never visible. 409 if (!Symbol.isInSection()) 410 return false; 411 412 if (Symbol.isUsedInReloc()) 413 return true; 414 415 return false; 416 } 417 418 const MCSymbol *MCAssembler::getAtom(const MCSymbol &S) const { 419 // Linker visible symbols define atoms. 420 if (isSymbolLinkerVisible(S)) 421 return &S; 422 423 // Absolute and undefined symbols have no defining atom. 424 if (!S.isInSection()) 425 return nullptr; 426 427 // Non-linker visible symbols in sections which can't be atomized have no 428 // defining atom. 429 if (!getContext().getAsmInfo()->isSectionAtomizableBySymbols( 430 *S.getFragment()->getParent())) 431 return nullptr; 432 433 // Otherwise, return the atom for the containing fragment. 434 return S.getFragment()->getAtom(); 435 } 436 437 bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout, 438 const MCFixup &Fixup, const MCFragment *DF, 439 MCValue &Target, uint64_t &Value) const { 440 ++stats::evaluateFixup; 441 442 // FIXME: This code has some duplication with recordRelocation. We should 443 // probably merge the two into a single callback that tries to evaluate a 444 // fixup and records a relocation if one is needed. 445 const MCExpr *Expr = Fixup.getValue(); 446 if (!Expr->evaluateAsRelocatable(Target, &Layout, &Fixup)) { 447 getContext().reportError(Fixup.getLoc(), "expected relocatable expression"); 448 // Claim to have completely evaluated the fixup, to prevent any further 449 // processing from being done. 450 Value = 0; 451 return true; 452 } 453 454 bool IsPCRel = Backend.getFixupKindInfo( 455 Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel; 456 457 bool IsResolved; 458 if (IsPCRel) { 459 if (Target.getSymB()) { 460 IsResolved = false; 461 } else if (!Target.getSymA()) { 462 IsResolved = false; 463 } else { 464 const MCSymbolRefExpr *A = Target.getSymA(); 465 const MCSymbol &SA = A->getSymbol(); 466 if (A->getKind() != MCSymbolRefExpr::VK_None || SA.isUndefined()) { 467 IsResolved = false; 468 } else { 469 IsResolved = getWriter().isSymbolRefDifferenceFullyResolvedImpl( 470 *this, SA, *DF, false, true); 471 } 472 } 473 } else { 474 IsResolved = Target.isAbsolute(); 475 } 476 477 Value = Target.getConstant(); 478 479 if (const MCSymbolRefExpr *A = Target.getSymA()) { 480 const MCSymbol &Sym = A->getSymbol(); 481 if (Sym.isDefined()) 482 Value += Layout.getSymbolOffset(Sym); 483 } 484 if (const MCSymbolRefExpr *B = Target.getSymB()) { 485 const MCSymbol &Sym = B->getSymbol(); 486 if (Sym.isDefined()) 487 Value -= Layout.getSymbolOffset(Sym); 488 } 489 490 491 bool ShouldAlignPC = Backend.getFixupKindInfo(Fixup.getKind()).Flags & 492 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits; 493 assert((ShouldAlignPC ? IsPCRel : true) && 494 "FKF_IsAlignedDownTo32Bits is only allowed on PC-relative fixups!"); 495 496 if (IsPCRel) { 497 uint32_t Offset = Layout.getFragmentOffset(DF) + Fixup.getOffset(); 498 499 // A number of ARM fixups in Thumb mode require that the effective PC 500 // address be determined as the 32-bit aligned version of the actual offset. 501 if (ShouldAlignPC) Offset &= ~0x3; 502 Value -= Offset; 503 } 504 505 // Let the backend adjust the fixup value if necessary, including whether 506 // we need a relocation. 507 Backend.processFixupValue(*this, Layout, Fixup, DF, Target, Value, 508 IsResolved); 509 510 return IsResolved; 511 } 512 513 uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout, 514 const MCFragment &F) const { 515 switch (F.getKind()) { 516 case MCFragment::FT_Data: 517 return cast<MCDataFragment>(F).getContents().size(); 518 case MCFragment::FT_Relaxable: 519 return cast<MCRelaxableFragment>(F).getContents().size(); 520 case MCFragment::FT_CompactEncodedInst: 521 return cast<MCCompactEncodedInstFragment>(F).getContents().size(); 522 case MCFragment::FT_Fill: 523 return cast<MCFillFragment>(F).getSize(); 524 525 case MCFragment::FT_LEB: 526 return cast<MCLEBFragment>(F).getContents().size(); 527 528 case MCFragment::FT_SafeSEH: 529 return 4; 530 531 case MCFragment::FT_Align: { 532 const MCAlignFragment &AF = cast<MCAlignFragment>(F); 533 unsigned Offset = Layout.getFragmentOffset(&AF); 534 unsigned Size = OffsetToAlignment(Offset, AF.getAlignment()); 535 // If we are padding with nops, force the padding to be larger than the 536 // minimum nop size. 537 if (Size > 0 && AF.hasEmitNops()) { 538 while (Size % getBackend().getMinimumNopSize()) 539 Size += AF.getAlignment(); 540 } 541 if (Size > AF.getMaxBytesToEmit()) 542 return 0; 543 return Size; 544 } 545 546 case MCFragment::FT_Org: { 547 const MCOrgFragment &OF = cast<MCOrgFragment>(F); 548 MCValue Value; 549 if (!OF.getOffset().evaluateAsValue(Value, Layout)) 550 report_fatal_error("expected assembly-time absolute expression"); 551 552 // FIXME: We need a way to communicate this error. 553 uint64_t FragmentOffset = Layout.getFragmentOffset(&OF); 554 int64_t TargetLocation = Value.getConstant(); 555 if (const MCSymbolRefExpr *A = Value.getSymA()) { 556 uint64_t Val; 557 if (!Layout.getSymbolOffset(A->getSymbol(), Val)) 558 report_fatal_error("expected absolute expression"); 559 TargetLocation += Val; 560 } 561 int64_t Size = TargetLocation - FragmentOffset; 562 if (Size < 0 || Size >= 0x40000000) 563 report_fatal_error("invalid .org offset '" + Twine(TargetLocation) + 564 "' (at offset '" + Twine(FragmentOffset) + "')"); 565 return Size; 566 } 567 568 case MCFragment::FT_Dwarf: 569 return cast<MCDwarfLineAddrFragment>(F).getContents().size(); 570 case MCFragment::FT_DwarfFrame: 571 return cast<MCDwarfCallFrameFragment>(F).getContents().size(); 572 case MCFragment::FT_Dummy: 573 llvm_unreachable("Should not have been added"); 574 } 575 576 llvm_unreachable("invalid fragment kind"); 577 } 578 579 void MCAsmLayout::layoutFragment(MCFragment *F) { 580 MCFragment *Prev = F->getPrevNode(); 581 582 // We should never try to recompute something which is valid. 583 assert(!isFragmentValid(F) && "Attempt to recompute a valid fragment!"); 584 // We should never try to compute the fragment layout if its predecessor 585 // isn't valid. 586 assert((!Prev || isFragmentValid(Prev)) && 587 "Attempt to compute fragment before its predecessor!"); 588 589 ++stats::FragmentLayouts; 590 591 // Compute fragment offset and size. 592 if (Prev) 593 F->Offset = Prev->Offset + getAssembler().computeFragmentSize(*this, *Prev); 594 else 595 F->Offset = 0; 596 LastValidFragment[F->getParent()] = F; 597 598 // If bundling is enabled and this fragment has instructions in it, it has to 599 // obey the bundling restrictions. With padding, we'll have: 600 // 601 // 602 // BundlePadding 603 // ||| 604 // ------------------------------------- 605 // Prev |##########| F | 606 // ------------------------------------- 607 // ^ 608 // | 609 // F->Offset 610 // 611 // The fragment's offset will point to after the padding, and its computed 612 // size won't include the padding. 613 // 614 // When the -mc-relax-all flag is used, we optimize bundling by writting the 615 // padding directly into fragments when the instructions are emitted inside 616 // the streamer. When the fragment is larger than the bundle size, we need to 617 // ensure that it's bundle aligned. This means that if we end up with 618 // multiple fragments, we must emit bundle padding between fragments. 619 // 620 // ".align N" is an example of a directive that introduces multiple 621 // fragments. We could add a special case to handle ".align N" by emitting 622 // within-fragment padding (which would produce less padding when N is less 623 // than the bundle size), but for now we don't. 624 // 625 if (Assembler.isBundlingEnabled() && F->hasInstructions()) { 626 assert(isa<MCEncodedFragment>(F) && 627 "Only MCEncodedFragment implementations have instructions"); 628 uint64_t FSize = Assembler.computeFragmentSize(*this, *F); 629 630 if (!Assembler.getRelaxAll() && FSize > Assembler.getBundleAlignSize()) 631 report_fatal_error("Fragment can't be larger than a bundle size"); 632 633 uint64_t RequiredBundlePadding = computeBundlePadding(Assembler, F, 634 F->Offset, FSize); 635 if (RequiredBundlePadding > UINT8_MAX) 636 report_fatal_error("Padding cannot exceed 255 bytes"); 637 F->setBundlePadding(static_cast<uint8_t>(RequiredBundlePadding)); 638 F->Offset += RequiredBundlePadding; 639 } 640 } 641 642 void MCAssembler::registerSymbol(const MCSymbol &Symbol, bool *Created) { 643 bool New = !Symbol.isRegistered(); 644 if (Created) 645 *Created = New; 646 if (New) { 647 Symbol.setIsRegistered(true); 648 Symbols.push_back(&Symbol); 649 } 650 } 651 652 void MCAssembler::writeFragmentPadding(const MCFragment &F, uint64_t FSize, 653 MCObjectWriter *OW) const { 654 // Should NOP padding be written out before this fragment? 655 unsigned BundlePadding = F.getBundlePadding(); 656 if (BundlePadding > 0) { 657 assert(isBundlingEnabled() && 658 "Writing bundle padding with disabled bundling"); 659 assert(F.hasInstructions() && 660 "Writing bundle padding for a fragment without instructions"); 661 662 unsigned TotalLength = BundlePadding + static_cast<unsigned>(FSize); 663 if (F.alignToBundleEnd() && TotalLength > getBundleAlignSize()) { 664 // If the padding itself crosses a bundle boundary, it must be emitted 665 // in 2 pieces, since even nop instructions must not cross boundaries. 666 // v--------------v <- BundleAlignSize 667 // v---------v <- BundlePadding 668 // ---------------------------- 669 // | Prev |####|####| F | 670 // ---------------------------- 671 // ^-------------------^ <- TotalLength 672 unsigned DistanceToBoundary = TotalLength - getBundleAlignSize(); 673 if (!getBackend().writeNopData(DistanceToBoundary, OW)) 674 report_fatal_error("unable to write NOP sequence of " + 675 Twine(DistanceToBoundary) + " bytes"); 676 BundlePadding -= DistanceToBoundary; 677 } 678 if (!getBackend().writeNopData(BundlePadding, OW)) 679 report_fatal_error("unable to write NOP sequence of " + 680 Twine(BundlePadding) + " bytes"); 681 } 682 } 683 684 /// \brief Write the fragment \p F to the output file. 685 static void writeFragment(const MCAssembler &Asm, const MCAsmLayout &Layout, 686 const MCFragment &F) { 687 MCObjectWriter *OW = &Asm.getWriter(); 688 689 // FIXME: Embed in fragments instead? 690 uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F); 691 692 Asm.writeFragmentPadding(F, FragmentSize, OW); 693 694 // This variable (and its dummy usage) is to participate in the assert at 695 // the end of the function. 696 uint64_t Start = OW->getStream().tell(); 697 (void) Start; 698 699 ++stats::EmittedFragments; 700 701 switch (F.getKind()) { 702 case MCFragment::FT_Align: { 703 ++stats::EmittedAlignFragments; 704 const MCAlignFragment &AF = cast<MCAlignFragment>(F); 705 assert(AF.getValueSize() && "Invalid virtual align in concrete fragment!"); 706 707 uint64_t Count = FragmentSize / AF.getValueSize(); 708 709 // FIXME: This error shouldn't actually occur (the front end should emit 710 // multiple .align directives to enforce the semantics it wants), but is 711 // severe enough that we want to report it. How to handle this? 712 if (Count * AF.getValueSize() != FragmentSize) 713 report_fatal_error("undefined .align directive, value size '" + 714 Twine(AF.getValueSize()) + 715 "' is not a divisor of padding size '" + 716 Twine(FragmentSize) + "'"); 717 718 // See if we are aligning with nops, and if so do that first to try to fill 719 // the Count bytes. Then if that did not fill any bytes or there are any 720 // bytes left to fill use the Value and ValueSize to fill the rest. 721 // If we are aligning with nops, ask that target to emit the right data. 722 if (AF.hasEmitNops()) { 723 if (!Asm.getBackend().writeNopData(Count, OW)) 724 report_fatal_error("unable to write nop sequence of " + 725 Twine(Count) + " bytes"); 726 break; 727 } 728 729 // Otherwise, write out in multiples of the value size. 730 for (uint64_t i = 0; i != Count; ++i) { 731 switch (AF.getValueSize()) { 732 default: llvm_unreachable("Invalid size!"); 733 case 1: OW->write8 (uint8_t (AF.getValue())); break; 734 case 2: OW->write16(uint16_t(AF.getValue())); break; 735 case 4: OW->write32(uint32_t(AF.getValue())); break; 736 case 8: OW->write64(uint64_t(AF.getValue())); break; 737 } 738 } 739 break; 740 } 741 742 case MCFragment::FT_Data: 743 ++stats::EmittedDataFragments; 744 OW->writeBytes(cast<MCDataFragment>(F).getContents()); 745 break; 746 747 case MCFragment::FT_Relaxable: 748 ++stats::EmittedRelaxableFragments; 749 OW->writeBytes(cast<MCRelaxableFragment>(F).getContents()); 750 break; 751 752 case MCFragment::FT_CompactEncodedInst: 753 ++stats::EmittedCompactEncodedInstFragments; 754 OW->writeBytes(cast<MCCompactEncodedInstFragment>(F).getContents()); 755 break; 756 757 case MCFragment::FT_Fill: { 758 ++stats::EmittedFillFragments; 759 const MCFillFragment &FF = cast<MCFillFragment>(F); 760 761 assert(FF.getValueSize() && "Invalid virtual align in concrete fragment!"); 762 763 for (uint64_t i = 0, e = FF.getSize() / FF.getValueSize(); i != e; ++i) { 764 switch (FF.getValueSize()) { 765 default: llvm_unreachable("Invalid size!"); 766 case 1: OW->write8 (uint8_t (FF.getValue())); break; 767 case 2: OW->write16(uint16_t(FF.getValue())); break; 768 case 4: OW->write32(uint32_t(FF.getValue())); break; 769 case 8: OW->write64(uint64_t(FF.getValue())); break; 770 } 771 } 772 break; 773 } 774 775 case MCFragment::FT_LEB: { 776 const MCLEBFragment &LF = cast<MCLEBFragment>(F); 777 OW->writeBytes(LF.getContents()); 778 break; 779 } 780 781 case MCFragment::FT_SafeSEH: { 782 const MCSafeSEHFragment &SF = cast<MCSafeSEHFragment>(F); 783 OW->write32(SF.getSymbol()->getIndex()); 784 break; 785 } 786 787 case MCFragment::FT_Org: { 788 ++stats::EmittedOrgFragments; 789 const MCOrgFragment &OF = cast<MCOrgFragment>(F); 790 791 for (uint64_t i = 0, e = FragmentSize; i != e; ++i) 792 OW->write8(uint8_t(OF.getValue())); 793 794 break; 795 } 796 797 case MCFragment::FT_Dwarf: { 798 const MCDwarfLineAddrFragment &OF = cast<MCDwarfLineAddrFragment>(F); 799 OW->writeBytes(OF.getContents()); 800 break; 801 } 802 case MCFragment::FT_DwarfFrame: { 803 const MCDwarfCallFrameFragment &CF = cast<MCDwarfCallFrameFragment>(F); 804 OW->writeBytes(CF.getContents()); 805 break; 806 } 807 case MCFragment::FT_Dummy: 808 llvm_unreachable("Should not have been added"); 809 } 810 811 assert(OW->getStream().tell() - Start == FragmentSize && 812 "The stream should advance by fragment size"); 813 } 814 815 void MCAssembler::writeSectionData(const MCSection *Sec, 816 const MCAsmLayout &Layout) const { 817 // Ignore virtual sections. 818 if (Sec->isVirtualSection()) { 819 assert(Layout.getSectionFileSize(Sec) == 0 && "Invalid size for section!"); 820 821 // Check that contents are only things legal inside a virtual section. 822 for (const MCFragment &F : *Sec) { 823 switch (F.getKind()) { 824 default: llvm_unreachable("Invalid fragment in virtual section!"); 825 case MCFragment::FT_Data: { 826 // Check that we aren't trying to write a non-zero contents (or fixups) 827 // into a virtual section. This is to support clients which use standard 828 // directives to fill the contents of virtual sections. 829 const MCDataFragment &DF = cast<MCDataFragment>(F); 830 assert(DF.fixup_begin() == DF.fixup_end() && 831 "Cannot have fixups in virtual section!"); 832 for (unsigned i = 0, e = DF.getContents().size(); i != e; ++i) 833 if (DF.getContents()[i]) { 834 if (auto *ELFSec = dyn_cast<const MCSectionELF>(Sec)) 835 report_fatal_error("non-zero initializer found in section '" + 836 ELFSec->getSectionName() + "'"); 837 else 838 report_fatal_error("non-zero initializer found in virtual section"); 839 } 840 break; 841 } 842 case MCFragment::FT_Align: 843 // Check that we aren't trying to write a non-zero value into a virtual 844 // section. 845 assert((cast<MCAlignFragment>(F).getValueSize() == 0 || 846 cast<MCAlignFragment>(F).getValue() == 0) && 847 "Invalid align in virtual section!"); 848 break; 849 case MCFragment::FT_Fill: 850 assert((cast<MCFillFragment>(F).getValueSize() == 0 || 851 cast<MCFillFragment>(F).getValue() == 0) && 852 "Invalid fill in virtual section!"); 853 break; 854 } 855 } 856 857 return; 858 } 859 860 uint64_t Start = getWriter().getStream().tell(); 861 (void)Start; 862 863 for (const MCFragment &F : *Sec) 864 writeFragment(*this, Layout, F); 865 866 assert(getWriter().getStream().tell() - Start == 867 Layout.getSectionAddressSize(Sec)); 868 } 869 870 std::pair<uint64_t, bool> MCAssembler::handleFixup(const MCAsmLayout &Layout, 871 MCFragment &F, 872 const MCFixup &Fixup) { 873 // Evaluate the fixup. 874 MCValue Target; 875 uint64_t FixedValue; 876 bool IsPCRel = Backend.getFixupKindInfo(Fixup.getKind()).Flags & 877 MCFixupKindInfo::FKF_IsPCRel; 878 if (!evaluateFixup(Layout, Fixup, &F, Target, FixedValue)) { 879 // The fixup was unresolved, we need a relocation. Inform the object 880 // writer of the relocation, and give it an opportunity to adjust the 881 // fixup value if need be. 882 getWriter().recordRelocation(*this, Layout, &F, Fixup, Target, IsPCRel, 883 FixedValue); 884 } 885 return std::make_pair(FixedValue, IsPCRel); 886 } 887 888 void MCAssembler::layout(MCAsmLayout &Layout) { 889 DEBUG_WITH_TYPE("mc-dump", { 890 llvm::errs() << "assembler backend - pre-layout\n--\n"; 891 dump(); }); 892 893 // Create dummy fragments and assign section ordinals. 894 unsigned SectionIndex = 0; 895 for (MCSection &Sec : *this) { 896 // Create dummy fragments to eliminate any empty sections, this simplifies 897 // layout. 898 if (Sec.getFragmentList().empty()) 899 new MCDataFragment(&Sec); 900 901 Sec.setOrdinal(SectionIndex++); 902 } 903 904 // Assign layout order indices to sections and fragments. 905 for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) { 906 MCSection *Sec = Layout.getSectionOrder()[i]; 907 Sec->setLayoutOrder(i); 908 909 unsigned FragmentIndex = 0; 910 for (MCFragment &Frag : *Sec) 911 Frag.setLayoutOrder(FragmentIndex++); 912 } 913 914 // Layout until everything fits. 915 while (layoutOnce(Layout)) 916 continue; 917 918 DEBUG_WITH_TYPE("mc-dump", { 919 llvm::errs() << "assembler backend - post-relaxation\n--\n"; 920 dump(); }); 921 922 // Finalize the layout, including fragment lowering. 923 finishLayout(Layout); 924 925 DEBUG_WITH_TYPE("mc-dump", { 926 llvm::errs() << "assembler backend - final-layout\n--\n"; 927 dump(); }); 928 929 // Allow the object writer a chance to perform post-layout binding (for 930 // example, to set the index fields in the symbol data). 931 getWriter().executePostLayoutBinding(*this, Layout); 932 933 // Evaluate and apply the fixups, generating relocation entries as necessary. 934 for (MCSection &Sec : *this) { 935 for (MCFragment &Frag : Sec) { 936 MCEncodedFragment *F = dyn_cast<MCEncodedFragment>(&Frag); 937 // Data and relaxable fragments both have fixups. So only process 938 // those here. 939 // FIXME: Is there a better way to do this? MCEncodedFragmentWithFixups 940 // being templated makes this tricky. 941 if (!F || isa<MCCompactEncodedInstFragment>(F)) 942 continue; 943 ArrayRef<MCFixup> Fixups; 944 MutableArrayRef<char> Contents; 945 if (auto *FragWithFixups = dyn_cast<MCDataFragment>(F)) { 946 Fixups = FragWithFixups->getFixups(); 947 Contents = FragWithFixups->getContents(); 948 } else if (auto *FragWithFixups = dyn_cast<MCRelaxableFragment>(F)) { 949 Fixups = FragWithFixups->getFixups(); 950 Contents = FragWithFixups->getContents(); 951 } else 952 llvm_unreachable("Unknown fragment with fixups!"); 953 for (const MCFixup &Fixup : Fixups) { 954 uint64_t FixedValue; 955 bool IsPCRel; 956 std::tie(FixedValue, IsPCRel) = handleFixup(Layout, *F, Fixup); 957 getBackend().applyFixup(Fixup, Contents.data(), 958 Contents.size(), FixedValue, IsPCRel); 959 } 960 } 961 } 962 } 963 964 void MCAssembler::Finish() { 965 // Create the layout object. 966 MCAsmLayout Layout(*this); 967 layout(Layout); 968 969 raw_ostream &OS = getWriter().getStream(); 970 uint64_t StartOffset = OS.tell(); 971 972 // Write the object file. 973 getWriter().writeObject(*this, Layout); 974 975 stats::ObjectBytes += OS.tell() - StartOffset; 976 } 977 978 bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup, 979 const MCRelaxableFragment *DF, 980 const MCAsmLayout &Layout) const { 981 MCValue Target; 982 uint64_t Value; 983 bool Resolved = evaluateFixup(Layout, Fixup, DF, Target, Value); 984 return getBackend().fixupNeedsRelaxationAdvanced(Fixup, Resolved, Value, DF, 985 Layout); 986 } 987 988 bool MCAssembler::fragmentNeedsRelaxation(const MCRelaxableFragment *F, 989 const MCAsmLayout &Layout) const { 990 // If this inst doesn't ever need relaxation, ignore it. This occurs when we 991 // are intentionally pushing out inst fragments, or because we relaxed a 992 // previous instruction to one that doesn't need relaxation. 993 if (!getBackend().mayNeedRelaxation(F->getInst())) 994 return false; 995 996 for (const MCFixup &Fixup : F->getFixups()) 997 if (fixupNeedsRelaxation(Fixup, F, Layout)) 998 return true; 999 1000 return false; 1001 } 1002 1003 bool MCAssembler::relaxInstruction(MCAsmLayout &Layout, 1004 MCRelaxableFragment &F) { 1005 if (!fragmentNeedsRelaxation(&F, Layout)) 1006 return false; 1007 1008 ++stats::RelaxedInstructions; 1009 1010 // FIXME-PERF: We could immediately lower out instructions if we can tell 1011 // they are fully resolved, to avoid retesting on later passes. 1012 1013 // Relax the fragment. 1014 1015 MCInst Relaxed; 1016 getBackend().relaxInstruction(F.getInst(), Relaxed); 1017 1018 // Encode the new instruction. 1019 // 1020 // FIXME-PERF: If it matters, we could let the target do this. It can 1021 // probably do so more efficiently in many cases. 1022 SmallVector<MCFixup, 4> Fixups; 1023 SmallString<256> Code; 1024 raw_svector_ostream VecOS(Code); 1025 getEmitter().encodeInstruction(Relaxed, VecOS, Fixups, F.getSubtargetInfo()); 1026 1027 // Update the fragment. 1028 F.setInst(Relaxed); 1029 F.getContents() = Code; 1030 F.getFixups() = Fixups; 1031 1032 return true; 1033 } 1034 1035 bool MCAssembler::relaxLEB(MCAsmLayout &Layout, MCLEBFragment &LF) { 1036 uint64_t OldSize = LF.getContents().size(); 1037 int64_t Value; 1038 bool Abs = LF.getValue().evaluateKnownAbsolute(Value, Layout); 1039 if (!Abs) 1040 report_fatal_error("sleb128 and uleb128 expressions must be absolute"); 1041 SmallString<8> &Data = LF.getContents(); 1042 Data.clear(); 1043 raw_svector_ostream OSE(Data); 1044 if (LF.isSigned()) 1045 encodeSLEB128(Value, OSE); 1046 else 1047 encodeULEB128(Value, OSE); 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, getDWARFLinetableParams(), LineDelta, 1065 AddrDelta, OSE); 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 return OldSize != Data.size(); 1082 } 1083 1084 bool MCAssembler::layoutSectionOnce(MCAsmLayout &Layout, MCSection &Sec) { 1085 // Holds the first fragment which needed relaxing during this layout. It will 1086 // remain NULL if none were relaxed. 1087 // When a fragment is relaxed, all the fragments following it should get 1088 // invalidated because their offset is going to change. 1089 MCFragment *FirstRelaxedFragment = nullptr; 1090 1091 // Attempt to relax all the fragments in the section. 1092 for (MCSection::iterator I = Sec.begin(), IE = Sec.end(); I != IE; ++I) { 1093 // Check if this is a fragment that needs relaxation. 1094 bool RelaxedFrag = false; 1095 switch(I->getKind()) { 1096 default: 1097 break; 1098 case MCFragment::FT_Relaxable: 1099 assert(!getRelaxAll() && 1100 "Did not expect a MCRelaxableFragment in RelaxAll mode"); 1101 RelaxedFrag = relaxInstruction(Layout, *cast<MCRelaxableFragment>(I)); 1102 break; 1103 case MCFragment::FT_Dwarf: 1104 RelaxedFrag = relaxDwarfLineAddr(Layout, 1105 *cast<MCDwarfLineAddrFragment>(I)); 1106 break; 1107 case MCFragment::FT_DwarfFrame: 1108 RelaxedFrag = 1109 relaxDwarfCallFrameFragment(Layout, 1110 *cast<MCDwarfCallFrameFragment>(I)); 1111 break; 1112 case MCFragment::FT_LEB: 1113 RelaxedFrag = relaxLEB(Layout, *cast<MCLEBFragment>(I)); 1114 break; 1115 } 1116 if (RelaxedFrag && !FirstRelaxedFragment) 1117 FirstRelaxedFragment = &*I; 1118 } 1119 if (FirstRelaxedFragment) { 1120 Layout.invalidateFragmentsFrom(FirstRelaxedFragment); 1121 return true; 1122 } 1123 return false; 1124 } 1125 1126 bool MCAssembler::layoutOnce(MCAsmLayout &Layout) { 1127 ++stats::RelaxationSteps; 1128 1129 bool WasRelaxed = false; 1130 for (iterator it = begin(), ie = end(); it != ie; ++it) { 1131 MCSection &Sec = *it; 1132 while (layoutSectionOnce(Layout, Sec)) 1133 WasRelaxed = true; 1134 } 1135 1136 return WasRelaxed; 1137 } 1138 1139 void MCAssembler::finishLayout(MCAsmLayout &Layout) { 1140 // The layout is done. Mark every fragment as valid. 1141 for (unsigned int i = 0, n = Layout.getSectionOrder().size(); i != n; ++i) { 1142 Layout.getFragmentOffset(&*Layout.getSectionOrder()[i]->rbegin()); 1143 } 1144 } 1145 1146 // Debugging methods 1147 1148 namespace llvm { 1149 1150 raw_ostream &operator<<(raw_ostream &OS, const MCFixup &AF) { 1151 OS << "<MCFixup" << " Offset:" << AF.getOffset() 1152 << " Value:" << *AF.getValue() 1153 << " Kind:" << AF.getKind() << ">"; 1154 return OS; 1155 } 1156 1157 } 1158 1159 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 1160 void MCFragment::dump() { 1161 raw_ostream &OS = llvm::errs(); 1162 1163 OS << "<"; 1164 switch (getKind()) { 1165 case MCFragment::FT_Align: OS << "MCAlignFragment"; break; 1166 case MCFragment::FT_Data: OS << "MCDataFragment"; break; 1167 case MCFragment::FT_CompactEncodedInst: 1168 OS << "MCCompactEncodedInstFragment"; break; 1169 case MCFragment::FT_Fill: OS << "MCFillFragment"; break; 1170 case MCFragment::FT_Relaxable: OS << "MCRelaxableFragment"; break; 1171 case MCFragment::FT_Org: OS << "MCOrgFragment"; break; 1172 case MCFragment::FT_Dwarf: OS << "MCDwarfFragment"; break; 1173 case MCFragment::FT_DwarfFrame: OS << "MCDwarfCallFrameFragment"; break; 1174 case MCFragment::FT_LEB: OS << "MCLEBFragment"; break; 1175 case MCFragment::FT_SafeSEH: OS << "MCSafeSEHFragment"; break; 1176 case MCFragment::FT_Dummy: 1177 OS << "MCDummyFragment"; 1178 break; 1179 } 1180 1181 OS << "<MCFragment " << (void*) this << " LayoutOrder:" << LayoutOrder 1182 << " Offset:" << Offset 1183 << " HasInstructions:" << hasInstructions() 1184 << " BundlePadding:" << static_cast<unsigned>(getBundlePadding()) << ">"; 1185 1186 switch (getKind()) { 1187 case MCFragment::FT_Align: { 1188 const MCAlignFragment *AF = cast<MCAlignFragment>(this); 1189 if (AF->hasEmitNops()) 1190 OS << " (emit nops)"; 1191 OS << "\n "; 1192 OS << " Alignment:" << AF->getAlignment() 1193 << " Value:" << AF->getValue() << " ValueSize:" << AF->getValueSize() 1194 << " MaxBytesToEmit:" << AF->getMaxBytesToEmit() << ">"; 1195 break; 1196 } 1197 case MCFragment::FT_Data: { 1198 const MCDataFragment *DF = cast<MCDataFragment>(this); 1199 OS << "\n "; 1200 OS << " Contents:["; 1201 const SmallVectorImpl<char> &Contents = DF->getContents(); 1202 for (unsigned i = 0, e = Contents.size(); i != e; ++i) { 1203 if (i) OS << ","; 1204 OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); 1205 } 1206 OS << "] (" << Contents.size() << " bytes)"; 1207 1208 if (DF->fixup_begin() != DF->fixup_end()) { 1209 OS << ",\n "; 1210 OS << " Fixups:["; 1211 for (MCDataFragment::const_fixup_iterator it = DF->fixup_begin(), 1212 ie = DF->fixup_end(); it != ie; ++it) { 1213 if (it != DF->fixup_begin()) OS << ",\n "; 1214 OS << *it; 1215 } 1216 OS << "]"; 1217 } 1218 break; 1219 } 1220 case MCFragment::FT_CompactEncodedInst: { 1221 const MCCompactEncodedInstFragment *CEIF = 1222 cast<MCCompactEncodedInstFragment>(this); 1223 OS << "\n "; 1224 OS << " Contents:["; 1225 const SmallVectorImpl<char> &Contents = CEIF->getContents(); 1226 for (unsigned i = 0, e = Contents.size(); i != e; ++i) { 1227 if (i) OS << ","; 1228 OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF); 1229 } 1230 OS << "] (" << Contents.size() << " bytes)"; 1231 break; 1232 } 1233 case MCFragment::FT_Fill: { 1234 const MCFillFragment *FF = cast<MCFillFragment>(this); 1235 OS << " Value:" << FF->getValue() << " ValueSize:" << FF->getValueSize() 1236 << " Size:" << FF->getSize(); 1237 break; 1238 } 1239 case MCFragment::FT_Relaxable: { 1240 const MCRelaxableFragment *F = cast<MCRelaxableFragment>(this); 1241 OS << "\n "; 1242 OS << " Inst:"; 1243 F->getInst().dump_pretty(OS); 1244 break; 1245 } 1246 case MCFragment::FT_Org: { 1247 const MCOrgFragment *OF = cast<MCOrgFragment>(this); 1248 OS << "\n "; 1249 OS << " Offset:" << OF->getOffset() << " Value:" << OF->getValue(); 1250 break; 1251 } 1252 case MCFragment::FT_Dwarf: { 1253 const MCDwarfLineAddrFragment *OF = cast<MCDwarfLineAddrFragment>(this); 1254 OS << "\n "; 1255 OS << " AddrDelta:" << OF->getAddrDelta() 1256 << " LineDelta:" << OF->getLineDelta(); 1257 break; 1258 } 1259 case MCFragment::FT_DwarfFrame: { 1260 const MCDwarfCallFrameFragment *CF = cast<MCDwarfCallFrameFragment>(this); 1261 OS << "\n "; 1262 OS << " AddrDelta:" << CF->getAddrDelta(); 1263 break; 1264 } 1265 case MCFragment::FT_LEB: { 1266 const MCLEBFragment *LF = cast<MCLEBFragment>(this); 1267 OS << "\n "; 1268 OS << " Value:" << LF->getValue() << " Signed:" << LF->isSigned(); 1269 break; 1270 } 1271 case MCFragment::FT_SafeSEH: { 1272 const MCSafeSEHFragment *F = cast<MCSafeSEHFragment>(this); 1273 OS << "\n "; 1274 OS << " Sym:" << F->getSymbol(); 1275 break; 1276 } 1277 case MCFragment::FT_Dummy: 1278 break; 1279 } 1280 OS << ">"; 1281 } 1282 1283 void MCAssembler::dump() { 1284 raw_ostream &OS = llvm::errs(); 1285 1286 OS << "<MCAssembler\n"; 1287 OS << " Sections:[\n "; 1288 for (iterator it = begin(), ie = end(); it != ie; ++it) { 1289 if (it != begin()) OS << ",\n "; 1290 it->dump(); 1291 } 1292 OS << "],\n"; 1293 OS << " Symbols:["; 1294 1295 for (symbol_iterator it = symbol_begin(), ie = symbol_end(); it != ie; ++it) { 1296 if (it != symbol_begin()) OS << ",\n "; 1297 OS << "("; 1298 it->dump(); 1299 OS << ", Index:" << it->getIndex() << ", "; 1300 OS << ")"; 1301 } 1302 OS << "]>\n"; 1303 } 1304 #endif 1305