X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMCAssembler.cpp;h=66ba9b81f3aa5c0c567118b20238aef0fd5bd09b;hb=46aaf69e37287a9696b6cc5c49d10d0937ff052b;hp=6558a1b927b6ac5e5e4b9cb99045fb084275db50;hpb=187ce544b2c6fa5ee6545390f2d07bc471e4159b;p=oota-llvm.git diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp index 6558a1b927b..66ba9b81f3a 100644 --- a/lib/MC/MCAssembler.cpp +++ b/lib/MC/MCAssembler.cpp @@ -11,34 +11,33 @@ #include "llvm/MC/MCAssembler.h" #include "llvm/MC/MCAsmLayout.h" #include "llvm/MC/MCCodeEmitter.h" +#include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCFixupKindInfo.h" #include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSection.h" #include "llvm/MC/MCSymbol.h" #include "llvm/MC/MCValue.h" #include "llvm/MC/MCDwarf.h" -#include "llvm/ADT/OwningPtr.h" +#include "llvm/MC/MCAsmBackend.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/StringExtras.h" #include "llvm/ADT/Twine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/Target/TargetRegistry.h" -#include "llvm/Target/TargetAsmBackend.h" +#include "llvm/Support/TargetRegistry.h" -#include using namespace llvm; namespace { namespace stats { STATISTIC(EmittedFragments, "Number of emitted assembler fragments"); -STATISTIC(EvaluateFixup, "Number of evaluated fixups"); +STATISTIC(evaluateFixup, "Number of evaluated fixups"); STATISTIC(FragmentLayouts, "Number of fragment layouts"); STATISTIC(ObjectBytes, "Number of emitted object file bytes"); STATISTIC(RelaxationSteps, "Number of assembler layout and relaxation steps"); STATISTIC(RelaxedInstructions, "Number of relaxed instructions"); -STATISTIC(SectionLayouts, "Number of section layouts"); } } @@ -50,131 +49,105 @@ STATISTIC(SectionLayouts, "Number of section layouts"); /* *** */ MCAsmLayout::MCAsmLayout(MCAssembler &Asm) - : Assembler(Asm), LastValidFragment(0) + : Assembler(Asm), LastValidFragment() { // Compute the section layout order. Virtual sections must go last. for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) - if (!Asm.getBackend().isVirtualSection(it->getSection())) + if (!it->getSection().isVirtualSection()) SectionOrder.push_back(&*it); for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) - if (Asm.getBackend().isVirtualSection(it->getSection())) + if (it->getSection().isVirtualSection()) SectionOrder.push_back(&*it); } -bool MCAsmLayout::isSectionUpToDate(const MCSectionData *SD) const { - // The first section is always up-to-date. - unsigned Index = SD->getLayoutOrder(); - if (!Index) - return true; - - // Otherwise, sections are always implicitly computed when the preceeding - // fragment is layed out. - const MCSectionData *Prev = getSectionOrder()[Index - 1]; - return isFragmentUpToDate(&(Prev->getFragmentList().back())); -} - bool MCAsmLayout::isFragmentUpToDate(const MCFragment *F) const { - return (LastValidFragment && - F->getLayoutOrder() <= LastValidFragment->getLayoutOrder()); + const MCSectionData &SD = *F->getParent(); + const MCFragment *LastValid = LastValidFragment.lookup(&SD); + if (!LastValid) + return false; + assert(LastValid->getParent() == F->getParent()); + return F->getLayoutOrder() <= LastValid->getLayoutOrder(); } -void MCAsmLayout::UpdateForSlide(MCFragment *F, int SlideAmount) { +void MCAsmLayout::Invalidate(MCFragment *F) { // If this fragment wasn't already up-to-date, we don't need to do anything. if (!isFragmentUpToDate(F)) return; - // Otherwise, reset the last valid fragment to the predecessor of the - // invalidated fragment. - LastValidFragment = F->getPrevNode(); - if (!LastValidFragment) { - unsigned Index = F->getParent()->getLayoutOrder(); - if (Index != 0) { - MCSectionData *Prev = getSectionOrder()[Index - 1]; - LastValidFragment = &(Prev->getFragmentList().back()); - } - } + // Otherwise, reset the last valid fragment to this fragment. + const MCSectionData &SD = *F->getParent(); + LastValidFragment[&SD] = F; } void MCAsmLayout::EnsureValid(const MCFragment *F) const { + MCSectionData &SD = *F->getParent(); + + MCFragment *Cur = LastValidFragment[&SD]; + if (!Cur) + Cur = &*SD.begin(); + else + Cur = Cur->getNextNode(); + // Advance the layout position until the fragment is up-to-date. while (!isFragmentUpToDate(F)) { - // Advance to the next fragment. - MCFragment *Cur = LastValidFragment; - if (Cur) - Cur = Cur->getNextNode(); - if (!Cur) { - unsigned NextIndex = 0; - if (LastValidFragment) - NextIndex = LastValidFragment->getParent()->getLayoutOrder() + 1; - Cur = SectionOrder[NextIndex]->begin(); - } - const_cast(this)->LayoutFragment(Cur); + Cur = Cur->getNextNode(); } } -void MCAsmLayout::FragmentReplaced(MCFragment *Src, MCFragment *Dst) { - if (LastValidFragment == Src) - LastValidFragment = Dst; - - Dst->Offset = Src->Offset; - Dst->EffectiveSize = Src->EffectiveSize; -} - -uint64_t MCAsmLayout::getFragmentAddress(const MCFragment *F) const { - assert(F->getParent() && "Missing section()!"); - return getSectionAddress(F->getParent()) + getFragmentOffset(F); -} - -uint64_t MCAsmLayout::getFragmentEffectiveSize(const MCFragment *F) const { - EnsureValid(F); - assert(F->EffectiveSize != ~UINT64_C(0) && "Address not set!"); - return F->EffectiveSize; -} - uint64_t MCAsmLayout::getFragmentOffset(const MCFragment *F) const { EnsureValid(F); assert(F->Offset != ~UINT64_C(0) && "Address not set!"); return F->Offset; } -uint64_t MCAsmLayout::getSymbolAddress(const MCSymbolData *SD) const { - assert(SD->getFragment() && "Invalid getAddress() on undefined symbol!"); - return getFragmentAddress(SD->getFragment()) + SD->getOffset(); -} +uint64_t MCAsmLayout::getSymbolOffset(const MCSymbolData *SD) const { + const MCSymbol &S = SD->getSymbol(); + + // If this is a variable, then recursively evaluate now. + if (S.isVariable()) { + MCValue Target; + if (!S.getVariableValue()->EvaluateAsRelocatable(Target, *this)) + report_fatal_error("unable to evaluate offset for variable '" + + S.getName() + "'"); + + // Verify that any used symbols are defined. + if (Target.getSymA() && Target.getSymA()->getSymbol().isUndefined()) + report_fatal_error("unable to evaluate offset to undefined symbol '" + + Target.getSymA()->getSymbol().getName() + "'"); + if (Target.getSymB() && Target.getSymB()->getSymbol().isUndefined()) + report_fatal_error("unable to evaluate offset to undefined symbol '" + + Target.getSymB()->getSymbol().getName() + "'"); -uint64_t MCAsmLayout::getSectionAddress(const MCSectionData *SD) const { - EnsureValid(SD->begin()); - assert(SD->Address != ~UINT64_C(0) && "Address not set!"); - return SD->Address; + uint64_t Offset = Target.getConstant(); + if (Target.getSymA()) + Offset += getSymbolOffset(&Assembler.getSymbolData( + Target.getSymA()->getSymbol())); + if (Target.getSymB()) + Offset -= getSymbolOffset(&Assembler.getSymbolData( + Target.getSymB()->getSymbol())); + return Offset; + } + + assert(SD->getFragment() && "Invalid getOffset() on undefined symbol!"); + return getFragmentOffset(SD->getFragment()) + SD->getOffset(); } uint64_t MCAsmLayout::getSectionAddressSize(const MCSectionData *SD) const { // The size is the last fragment's end offset. const MCFragment &F = SD->getFragmentList().back(); - return getFragmentOffset(&F) + getFragmentEffectiveSize(&F); + return getFragmentOffset(&F) + getAssembler().computeFragmentSize(*this, F); } uint64_t MCAsmLayout::getSectionFileSize(const MCSectionData *SD) const { // Virtual sections have no file size. - if (getAssembler().getBackend().isVirtualSection(SD->getSection())) + if (SD->getSection().isVirtualSection()) return 0; // Otherwise, the file size is the same as the address space size. return getSectionAddressSize(SD); } -uint64_t MCAsmLayout::getSectionSize(const MCSectionData *SD) const { - // The logical size is the address space size minus any tail padding. - uint64_t Size = getSectionAddressSize(SD); - const MCAlignFragment *AF = - dyn_cast(&(SD->getFragmentList().back())); - if (AF && AF->hasOnlyAlignAddress()) - Size -= getFragmentEffectiveSize(AF); - - return Size; -} - /* *** */ MCFragment::MCFragment() : Kind(FragmentType(~0)) { @@ -184,8 +157,7 @@ MCFragment::~MCFragment() { } MCFragment::MCFragment(FragmentType _Kind, MCSectionData *_Parent) - : Kind(_Kind), Parent(_Parent), Atom(0), Offset(~UINT64_C(0)), - EffectiveSize(~UINT64_C(0)) + : Kind(_Kind), Parent(_Parent), Atom(0), Offset(~UINT64_C(0)) { if (Parent) Parent->getFragmentList().push_back(this); @@ -197,8 +169,8 @@ MCSectionData::MCSectionData() : Section(0) {} MCSectionData::MCSectionData(const MCSection &_Section, MCAssembler *A) : Section(&_Section), + Ordinal(~UINT32_C(0)), Alignment(1), - Address(~UINT64_C(0)), HasInstructions(false) { if (A) @@ -222,12 +194,11 @@ MCSymbolData::MCSymbolData(const MCSymbol &_Symbol, MCFragment *_Fragment, /* *** */ -MCAssembler::MCAssembler(MCContext &_Context, TargetAsmBackend &_Backend, - MCCodeEmitter &_Emitter, bool _PadSectionToAlignment, - raw_ostream &_OS) - : Context(_Context), Backend(_Backend), Emitter(_Emitter), - OS(_OS), RelaxAll(false), SubsectionsViaSymbols(false), - PadSectionToAlignment(_PadSectionToAlignment) +MCAssembler::MCAssembler(MCContext &Context_, MCAsmBackend &Backend_, + MCCodeEmitter &Emitter_, MCObjectWriter &Writer_, + raw_ostream &OS_) + : Context(Context_), Backend(Backend_), Emitter(Emitter_), Writer(Writer_), + OS(OS_), RelaxAll(false), NoExecStack(false), SubsectionsViaSymbols(false) { } @@ -266,50 +237,78 @@ const MCSymbolData *MCAssembler::getAtom(const MCSymbolData *SD) const { return SD->getFragment()->getAtom(); } -bool MCAssembler::EvaluateFixup(const MCObjectWriter &Writer, - const MCAsmLayout &Layout, +bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout, const MCFixup &Fixup, const MCFragment *DF, MCValue &Target, uint64_t &Value) const { - ++stats::EvaluateFixup; + ++stats::evaluateFixup; + + if (!Fixup.getValue()->EvaluateAsRelocatable(Target, Layout)) + getContext().FatalError(Fixup.getLoc(), "expected relocatable expression"); - if (!Fixup.getValue()->EvaluateAsRelocatable(Target, &Layout)) - report_fatal_error("expected relocatable expression"); + bool IsPCRel = Backend.getFixupKindInfo( + Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel; - // FIXME: How do non-scattered symbols work in ELF? I presume the linker - // doesn't support small relocations, but then under what criteria does the - // assembler allow symbol differences? + bool IsResolved; + if (IsPCRel) { + if (Target.getSymB()) { + IsResolved = false; + } else if (!Target.getSymA()) { + IsResolved = false; + } else { + const MCSymbolRefExpr *A = Target.getSymA(); + const MCSymbol &SA = A->getSymbol(); + if (A->getKind() != MCSymbolRefExpr::VK_None || + SA.AliasedSymbol().isUndefined()) { + IsResolved = false; + } else { + const MCSymbolData &DataA = getSymbolData(SA); + IsResolved = + getWriter().IsSymbolRefDifferenceFullyResolvedImpl(*this, DataA, + *DF, false, true); + } + } + } else { + IsResolved = Target.isAbsolute(); + } Value = Target.getConstant(); - bool IsPCRel = Emitter.getFixupKindInfo( - Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel; - bool IsResolved = true; if (const MCSymbolRefExpr *A = Target.getSymA()) { - if (A->getSymbol().isDefined()) - Value += Layout.getSymbolAddress(&getSymbolData(A->getSymbol())); - else - IsResolved = false; + const MCSymbol &Sym = A->getSymbol().AliasedSymbol(); + if (Sym.isDefined()) + Value += Layout.getSymbolOffset(&getSymbolData(Sym)); } if (const MCSymbolRefExpr *B = Target.getSymB()) { - if (B->getSymbol().isDefined()) - Value -= Layout.getSymbolAddress(&getSymbolData(B->getSymbol())); - else - IsResolved = false; + const MCSymbol &Sym = B->getSymbol().AliasedSymbol(); + if (Sym.isDefined()) + Value -= Layout.getSymbolOffset(&getSymbolData(Sym)); } - if (IsResolved) - IsResolved = Writer.IsFixupFullyResolved(*this, Target, IsPCRel, DF); - if (IsPCRel) - Value -= Layout.getFragmentAddress(DF) + Fixup.getOffset(); + bool ShouldAlignPC = Backend.getFixupKindInfo(Fixup.getKind()).Flags & + MCFixupKindInfo::FKF_IsAlignedDownTo32Bits; + assert((ShouldAlignPC ? IsPCRel : true) && + "FKF_IsAlignedDownTo32Bits is only allowed on PC-relative fixups!"); + + if (IsPCRel) { + uint32_t Offset = Layout.getFragmentOffset(DF) + Fixup.getOffset(); + + // A number of ARM fixups in Thumb mode require that the effective PC + // address be determined as the 32-bit aligned version of the actual offset. + if (ShouldAlignPC) Offset &= ~0x3; + Value -= Offset; + } + + // Let the backend adjust the fixup value if necessary, including whether + // we need a relocation. + Backend.processFixupValue(*this, Layout, Fixup, DF, Target, Value, + IsResolved); return IsResolved; } -uint64_t MCAssembler::ComputeFragmentSize(MCAsmLayout &Layout, - const MCFragment &F, - uint64_t SectionAddress, - uint64_t FragmentOffset) const { +uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout, + const MCFragment &F) const { switch (F.getKind()) { case MCFragment::FT_Data: return cast(F).getContents().size(); @@ -319,52 +318,39 @@ uint64_t MCAssembler::ComputeFragmentSize(MCAsmLayout &Layout, return cast(F).getInstSize(); case MCFragment::FT_LEB: - return cast(F).getSize(); + return cast(F).getContents().size(); case MCFragment::FT_Align: { const MCAlignFragment &AF = cast(F); - - assert((!AF.hasOnlyAlignAddress() || !AF.getNextNode()) && - "Invalid OnlyAlignAddress bit, not the last fragment!"); - - uint64_t Size = OffsetToAlignment(SectionAddress + FragmentOffset, - AF.getAlignment()); - - // Honor MaxBytesToEmit. + unsigned Offset = Layout.getFragmentOffset(&AF); + unsigned Size = OffsetToAlignment(Offset, AF.getAlignment()); if (Size > AF.getMaxBytesToEmit()) return 0; - return Size; } - case MCFragment::FT_Org: - return cast(F).getSize(); - - case MCFragment::FT_Dwarf: { - const MCDwarfLineAddrFragment &OF = cast(F); - - // The AddrDelta is really unsigned and it can only increase. - int64_t AddrDelta; - - OF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, &Layout); - - int64_t LineDelta; - LineDelta = OF.getLineDelta(); - - return MCDwarfLineAddr::ComputeSize(LineDelta, AddrDelta); - } + case MCFragment::FT_Org: { + MCOrgFragment &OF = cast(F); + int64_t TargetLocation; + if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, Layout)) + report_fatal_error("expected assembly-time absolute expression"); + + // FIXME: We need a way to communicate this error. + uint64_t FragmentOffset = Layout.getFragmentOffset(&OF); + int64_t Size = TargetLocation - FragmentOffset; + if (Size < 0 || Size >= 0x40000000) + report_fatal_error("invalid .org offset '" + Twine(TargetLocation) + + "' (at offset '" + Twine(FragmentOffset) + "')"); + return Size; } - assert(0 && "invalid fragment kind"); - return 0; -} + case MCFragment::FT_Dwarf: + return cast(F).getContents().size(); + case MCFragment::FT_DwarfFrame: + return cast(F).getContents().size(); + } -void MCAsmLayout::LayoutFile() { - // Initialize the first section and set the valid fragment layout point. All - // actual layout computations are done lazily. - LastValidFragment = 0; - if (!getSectionOrder().empty()) - getSectionOrder().front()->Address = 0; + llvm_unreachable("invalid fragment kind"); } void MCAsmLayout::LayoutFragment(MCFragment *F) { @@ -372,10 +358,6 @@ void MCAsmLayout::LayoutFragment(MCFragment *F) { // We should never try to recompute something which is up-to-date. assert(!isFragmentUpToDate(F) && "Attempt to recompute up-to-date fragment!"); - // We should never try to compute the fragment layout if the section isn't - // up-to-date. - assert(isSectionUpToDate(F->getParent()) && - "Attempt to compute fragment before it's section!"); // We should never try to compute the fragment layout if it's predecessor // isn't up-to-date. assert((!Prev || isFragmentUpToDate(Prev)) && @@ -383,55 +365,26 @@ void MCAsmLayout::LayoutFragment(MCFragment *F) { ++stats::FragmentLayouts; - // Compute the fragment start address. - uint64_t StartAddress = F->getParent()->Address; - uint64_t Address = StartAddress; - if (Prev) - Address += Prev->Offset + Prev->EffectiveSize; - // Compute fragment offset and size. - F->Offset = Address - StartAddress; - F->EffectiveSize = getAssembler().ComputeFragmentSize(*this, *F, StartAddress, - F->Offset); - LastValidFragment = F; - - // If this is the last fragment in a section, update the next section address. - if (!F->getNextNode()) { - unsigned NextIndex = F->getParent()->getLayoutOrder() + 1; - if (NextIndex != getSectionOrder().size()) - LayoutSection(getSectionOrder()[NextIndex]); - } -} - -void MCAsmLayout::LayoutSection(MCSectionData *SD) { - unsigned SectionOrderIndex = SD->getLayoutOrder(); - - ++stats::SectionLayouts; - - // Compute the section start address. - uint64_t StartAddress = 0; - if (SectionOrderIndex) { - MCSectionData *Prev = getSectionOrder()[SectionOrderIndex - 1]; - StartAddress = getSectionAddress(Prev) + getSectionAddressSize(Prev); - } - - // Honor the section alignment requirements. - StartAddress = RoundUpToAlignment(StartAddress, SD->getAlignment()); + uint64_t Offset = 0; + if (Prev) + Offset += Prev->Offset + getAssembler().computeFragmentSize(*this, *Prev); - // Set the section address. - SD->Address = StartAddress; + F->Offset = Offset; + LastValidFragment[F->getParent()] = F; } /// WriteFragmentData - Write the \arg F data to the output file. static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, - const MCFragment &F, MCObjectWriter *OW) { + const MCFragment &F) { + MCObjectWriter *OW = &Asm.getWriter(); uint64_t Start = OW->getStream().tell(); (void) Start; ++stats::EmittedFragments; // FIXME: Embed in fragments instead? - uint64_t FragmentSize = Layout.getFragmentEffectiveSize(&F); + uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F); switch (F.getKind()) { case MCFragment::FT_Align: { MCAlignFragment &AF = cast(F); @@ -453,7 +406,7 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, // bytes left to fill use the the Value and ValueSize to fill the rest. // If we are aligning with nops, ask that target to emit the right data. if (AF.hasEmitNops()) { - if (!Asm.getBackend().WriteNopData(Count, OW)) + if (!Asm.getBackend().writeNopData(Count, OW)) report_fatal_error("unable to write nop sequence of " + Twine(Count) + " bytes"); break; @@ -462,8 +415,7 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, // Otherwise, write out in multiples of the value size. for (uint64_t i = 0; i != Count; ++i) { switch (AF.getValueSize()) { - default: - assert(0 && "Invalid size!"); + default: llvm_unreachable("Invalid size!"); case 1: OW->Write8 (uint8_t (AF.getValue())); break; case 2: OW->Write16(uint16_t(AF.getValue())); break; case 4: OW->Write32(uint32_t(AF.getValue())); break; @@ -487,8 +439,7 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, for (uint64_t i = 0, e = FF.getSize() / FF.getValueSize(); i != e; ++i) { switch (FF.getValueSize()) { - default: - assert(0 && "Invalid size!"); + default: llvm_unreachable("Invalid size!"); case 1: OW->Write8 (uint8_t (FF.getValue())); break; case 2: OW->Write16(uint16_t(FF.getValue())); break; case 4: OW->Write32(uint32_t(FF.getValue())); break; @@ -498,24 +449,15 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, break; } - case MCFragment::FT_Inst: - llvm_unreachable("unexpected inst fragment after lowering"); + case MCFragment::FT_Inst: { + MCInstFragment &IF = cast(F); + OW->WriteBytes(StringRef(IF.getCode().begin(), IF.getCode().size())); break; + } case MCFragment::FT_LEB: { MCLEBFragment &LF = cast(F); - - // FIXME: It is probably better if we don't call EvaluateAsAbsolute in - // here. - int64_t Value; - LF.getValue().EvaluateAsAbsolute(Value, &Layout); - SmallString<32> Tmp; - raw_svector_ostream OSE(Tmp); - if (LF.isSigned()) - MCObjectWriter::EncodeSLEB128(Value, OSE); - else - MCObjectWriter::EncodeULEB128(Value, OSE); - OW->WriteBytes(OSE.str()); + OW->WriteBytes(LF.getContents().str()); break; } @@ -530,15 +472,12 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, case MCFragment::FT_Dwarf: { const MCDwarfLineAddrFragment &OF = cast(F); - - // The AddrDelta is really unsigned and it can only increase. - int64_t AddrDelta; - OF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, &Layout); - - int64_t LineDelta; - LineDelta = OF.getLineDelta(); - - MCDwarfLineAddr::Write(OW, LineDelta, (uint64_t)AddrDelta); + OW->WriteBytes(OF.getContents().str()); + break; + } + case MCFragment::FT_DwarfFrame: { + const MCDwarfCallFrameFragment &CF = cast(F); + OW->WriteBytes(CF.getContents().str()); break; } } @@ -546,19 +485,17 @@ static void WriteFragmentData(const MCAssembler &Asm, const MCAsmLayout &Layout, assert(OW->getStream().tell() - Start == FragmentSize); } -void MCAssembler::WriteSectionData(const MCSectionData *SD, - const MCAsmLayout &Layout, - MCObjectWriter *OW) const { +void MCAssembler::writeSectionData(const MCSectionData *SD, + const MCAsmLayout &Layout) const { // Ignore virtual sections. - if (getBackend().isVirtualSection(SD->getSection())) { + if (SD->getSection().isVirtualSection()) { assert(Layout.getSectionFileSize(SD) == 0 && "Invalid size for section!"); // Check that contents are only things legal inside a virtual section. for (MCSectionData::const_iterator it = SD->begin(), ie = SD->end(); it != ie; ++it) { switch (it->getKind()) { - default: - assert(0 && "Invalid fragment in virtual section!"); + default: llvm_unreachable("Invalid fragment in virtual section!"); case MCFragment::FT_Data: { // Check that we aren't trying to write a non-zero contents (or fixups) // into a virtual section. This is to support clients which use standard @@ -588,52 +525,34 @@ void MCAssembler::WriteSectionData(const MCSectionData *SD, return; } - uint64_t Start = OW->getStream().tell(); + uint64_t Start = getWriter().getStream().tell(); (void) Start; for (MCSectionData::const_iterator it = SD->begin(), ie = SD->end(); it != ie; ++it) - WriteFragmentData(*this, Layout, *it, OW); + WriteFragmentData(*this, Layout, *it); - assert(OW->getStream().tell() - Start == Layout.getSectionFileSize(SD)); + assert(getWriter().getStream().tell() - Start == + Layout.getSectionAddressSize(SD)); } -void MCAssembler::AddSectionToTheEnd(const MCObjectWriter &Writer, - MCSectionData &SD, MCAsmLayout &Layout) { - // Create dummy fragments and assign section ordinals. - unsigned SectionIndex = 0; - for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) - SectionIndex++; - - SD.setOrdinal(SectionIndex); - // Assign layout order indices to sections and fragments. - unsigned FragmentIndex = 0; - unsigned i = 0; - for (unsigned e = Layout.getSectionOrder().size(); i != e; ++i) { - MCSectionData *SD = Layout.getSectionOrder()[i]; +uint64_t MCAssembler::handleFixup(const MCAsmLayout &Layout, + MCFragment &F, + const MCFixup &Fixup) { + // Evaluate the fixup. + MCValue Target; + uint64_t FixedValue; + if (!evaluateFixup(Layout, Fixup, &F, Target, FixedValue)) { + // The fixup was unresolved, we need a relocation. Inform the object + // writer of the relocation, and give it an opportunity to adjust the + // fixup value if need be. + getWriter().RecordRelocation(*this, Layout, &F, Fixup, Target, FixedValue); + } + return FixedValue; + } - for (MCSectionData::iterator it2 = SD->begin(), - ie2 = SD->end(); it2 != ie2; ++it2) - FragmentIndex++; - } - - SD.setLayoutOrder(i); - for (MCSectionData::iterator it2 = SD.begin(), - ie2 = SD.end(); it2 != ie2; ++it2) { - it2->setLayoutOrder(FragmentIndex++); - } - Layout.getSectionOrder().push_back(&SD); - - Layout.LayoutSection(&SD); - - // Layout until everything fits. - while (LayoutOnce(Writer, Layout)) - continue; - -} - -void MCAssembler::Finish(MCObjectWriter *Writer) { +void MCAssembler::Finish() { DEBUG_WITH_TYPE("mc-dump", { llvm::errs() << "assembler backend - pre-layout\n--\n"; dump(); }); @@ -641,30 +560,6 @@ void MCAssembler::Finish(MCObjectWriter *Writer) { // Create the layout object. MCAsmLayout Layout(*this); - // Insert additional align fragments for concrete sections to explicitly pad - // the previous section to match their alignment requirements. This is for - // 'gas' compatibility, it shouldn't strictly be necessary. - if (PadSectionToAlignment) { - for (unsigned i = 1, e = Layout.getSectionOrder().size(); i < e; ++i) { - MCSectionData *SD = Layout.getSectionOrder()[i]; - - // Ignore sections without alignment requirements. - unsigned Align = SD->getAlignment(); - if (Align <= 1) - continue; - - // Ignore virtual sections, they don't cause file size modifications. - if (getBackend().isVirtualSection(SD->getSection())) - continue; - - // Otherwise, create a new align fragment at the end of the previous - // section. - MCAlignFragment *AF = new MCAlignFragment(Align, 0, 1, Align, - Layout.getSectionOrder()[i - 1]); - AF->setOnlyAlignAddress(true); - } - } - // Create dummy fragments and assign section ordinals. unsigned SectionIndex = 0; for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { @@ -677,27 +572,18 @@ void MCAssembler::Finish(MCObjectWriter *Writer) { } // Assign layout order indices to sections and fragments. - unsigned FragmentIndex = 0; for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) { MCSectionData *SD = Layout.getSectionOrder()[i]; SD->setLayoutOrder(i); + unsigned FragmentIndex = 0; for (MCSectionData::iterator it2 = SD->begin(), ie2 = SD->end(); it2 != ie2; ++it2) it2->setLayoutOrder(FragmentIndex++); } - llvm::OwningPtr OwnWriter(0); - if (Writer == 0) { - //no custom Writer_ : create the default one life-managed by OwningPtr - OwnWriter.reset(getBackend().createObjectWriter(OS)); - Writer = OwnWriter.get(); - if (!Writer) - report_fatal_error("unable to create object writer!"); - } - // Layout until everything fits. - while (LayoutOnce(*Writer, Layout)) + while (layoutOnce(Layout)) continue; DEBUG_WITH_TYPE("mc-dump", { @@ -705,7 +591,7 @@ void MCAssembler::Finish(MCObjectWriter *Writer) { dump(); }); // Finalize the layout, including fragment lowering. - FinishLayout(Layout); + finishLayout(Layout); DEBUG_WITH_TYPE("mc-dump", { llvm::errs() << "assembler backend - final-layout\n--\n"; @@ -715,44 +601,43 @@ void MCAssembler::Finish(MCObjectWriter *Writer) { // Allow the object writer a chance to perform post-layout binding (for // example, to set the index fields in the symbol data). - Writer->ExecutePostLayoutBinding(*this); + getWriter().ExecutePostLayoutBinding(*this, Layout); // Evaluate and apply the fixups, generating relocation entries as necessary. for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) { for (MCSectionData::iterator it2 = it->begin(), ie2 = it->end(); it2 != ie2; ++it2) { MCDataFragment *DF = dyn_cast(it2); - if (!DF) - continue; - - for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(), - ie3 = DF->fixup_end(); it3 != ie3; ++it3) { - MCFixup &Fixup = *it3; - - // Evaluate the fixup. - MCValue Target; - uint64_t FixedValue; - if (!EvaluateFixup(*Writer, Layout, Fixup, DF, Target, FixedValue)) { - // The fixup was unresolved, we need a relocation. Inform the object - // writer of the relocation, and give it an opportunity to adjust the - // fixup value if need be. - Writer->RecordRelocation(*this, Layout, DF, Fixup, Target,FixedValue); + if (DF) { + for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(), + ie3 = DF->fixup_end(); it3 != ie3; ++it3) { + MCFixup &Fixup = *it3; + uint64_t FixedValue = handleFixup(Layout, *DF, Fixup); + getBackend().applyFixup(Fixup, DF->getContents().data(), + DF->getContents().size(), FixedValue); + } + } + MCInstFragment *IF = dyn_cast(it2); + if (IF) { + for (MCInstFragment::fixup_iterator it3 = IF->fixup_begin(), + ie3 = IF->fixup_end(); it3 != ie3; ++it3) { + MCFixup &Fixup = *it3; + uint64_t FixedValue = handleFixup(Layout, *IF, Fixup); + getBackend().applyFixup(Fixup, IF->getCode().data(), + IF->getCode().size(), FixedValue); } - - getBackend().ApplyFixup(Fixup, *DF, FixedValue); } } } // Write the object file. - Writer->WriteObject(*this, Layout); + getWriter().WriteObject(*this, Layout); stats::ObjectBytes += OS.tell() - StartOffset; } -bool MCAssembler::FixupNeedsRelaxation(const MCObjectWriter &Writer, - const MCFixup &Fixup, - const MCFragment *DF, +bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup, + const MCInstFragment *DF, const MCAsmLayout &Layout) const { if (getRelaxAll()) return true; @@ -760,36 +645,31 @@ bool MCAssembler::FixupNeedsRelaxation(const MCObjectWriter &Writer, // If we cannot resolve the fixup value, it requires relaxation. MCValue Target; uint64_t Value; - if (!EvaluateFixup(Writer, Layout, Fixup, DF, Target, Value)) + if (!evaluateFixup(Layout, Fixup, DF, Target, Value)) return true; - // Otherwise, relax if the value is too big for a (signed) i8. - // - // FIXME: This is target dependent! - return int64_t(Value) != int64_t(int8_t(Value)); + return getBackend().fixupNeedsRelaxation(Fixup, Value, DF, Layout); } -bool MCAssembler::FragmentNeedsRelaxation(const MCObjectWriter &Writer, - const MCInstFragment *IF, +bool MCAssembler::fragmentNeedsRelaxation(const MCInstFragment *IF, const MCAsmLayout &Layout) const { // If this inst doesn't ever need relaxation, ignore it. This occurs when we // are intentionally pushing out inst fragments, or because we relaxed a // previous instruction to one that doesn't need relaxation. - if (!getBackend().MayNeedRelaxation(IF->getInst())) + if (!getBackend().mayNeedRelaxation(IF->getInst())) return false; for (MCInstFragment::const_fixup_iterator it = IF->fixup_begin(), ie = IF->fixup_end(); it != ie; ++it) - if (FixupNeedsRelaxation(Writer, *it, IF, Layout)) + if (fixupNeedsRelaxation(*it, IF, Layout)) return true; return false; } -bool MCAssembler::RelaxInstruction(const MCObjectWriter &Writer, - MCAsmLayout &Layout, +bool MCAssembler::relaxInstruction(MCAsmLayout &Layout, MCInstFragment &IF) { - if (!FragmentNeedsRelaxation(Writer, &IF, Layout)) + if (!fragmentNeedsRelaxation(&IF, Layout)) return false; ++stats::RelaxedInstructions; @@ -800,7 +680,7 @@ bool MCAssembler::RelaxInstruction(const MCObjectWriter &Writer, // Relax the fragment. MCInst Relaxed; - getBackend().RelaxInstruction(IF.getInst(), Relaxed); + getBackend().relaxInstruction(IF.getInst(), Relaxed); // Encode the new instruction. // @@ -813,7 +693,6 @@ bool MCAssembler::RelaxInstruction(const MCObjectWriter &Writer, VecOS.flush(); // Update the instruction fragment. - int SlideAmount = Code.size() - IF.getInstSize(); IF.setInst(Relaxed); IF.getCode() = Code; IF.getFixups().clear(); @@ -821,119 +700,113 @@ bool MCAssembler::RelaxInstruction(const MCObjectWriter &Writer, for (unsigned i = 0, e = Fixups.size(); i != e; ++i) IF.getFixups().push_back(Fixups[i]); - // Update the layout, and remember that we relaxed. - Layout.UpdateForSlide(&IF, SlideAmount); return true; } -bool MCAssembler::RelaxOrg(const MCObjectWriter &Writer, - MCAsmLayout &Layout, - MCOrgFragment &OF) { - int64_t TargetLocation; - if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, &Layout)) - report_fatal_error("expected assembly-time absolute expression"); - - // FIXME: We need a way to communicate this error. - uint64_t FragmentOffset = Layout.getFragmentOffset(&OF); - int64_t Offset = TargetLocation - FragmentOffset; - if (Offset < 0 || Offset >= 0x40000000) - report_fatal_error("invalid .org offset '" + Twine(TargetLocation) + - "' (at offset '" + Twine(FragmentOffset) + "')"); - - unsigned OldSize = OF.getSize(); - OF.setSize(Offset); - return OldSize != OF.getSize(); -} - -bool MCAssembler::RelaxLEB(const MCObjectWriter &Writer, - MCAsmLayout &Layout, - MCLEBFragment &LF) { - int64_t Value; - LF.getValue().EvaluateAsAbsolute(Value, &Layout); - SmallString<32> Tmp; - raw_svector_ostream OSE(Tmp); +bool MCAssembler::relaxLEB(MCAsmLayout &Layout, MCLEBFragment &LF) { + int64_t Value = 0; + uint64_t OldSize = LF.getContents().size(); + bool IsAbs = LF.getValue().EvaluateAsAbsolute(Value, Layout); + (void)IsAbs; + assert(IsAbs); + SmallString<8> &Data = LF.getContents(); + Data.clear(); + raw_svector_ostream OSE(Data); if (LF.isSigned()) MCObjectWriter::EncodeSLEB128(Value, OSE); else MCObjectWriter::EncodeULEB128(Value, OSE); - uint64_t OldSize = LF.getSize(); - LF.setSize(OSE.GetNumBytesInBuffer()); - return OldSize != LF.getSize(); + OSE.flush(); + return OldSize != LF.getContents().size(); +} + +bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout, + MCDwarfLineAddrFragment &DF) { + int64_t AddrDelta = 0; + uint64_t OldSize = DF.getContents().size(); + bool IsAbs = DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout); + (void)IsAbs; + assert(IsAbs); + int64_t LineDelta; + LineDelta = DF.getLineDelta(); + SmallString<8> &Data = DF.getContents(); + Data.clear(); + raw_svector_ostream OSE(Data); + MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OSE); + OSE.flush(); + return OldSize != Data.size(); +} + +bool MCAssembler::relaxDwarfCallFrameFragment(MCAsmLayout &Layout, + MCDwarfCallFrameFragment &DF) { + int64_t AddrDelta = 0; + uint64_t OldSize = DF.getContents().size(); + bool IsAbs = DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout); + (void)IsAbs; + assert(IsAbs); + SmallString<8> &Data = DF.getContents(); + Data.clear(); + raw_svector_ostream OSE(Data); + MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OSE); + OSE.flush(); + return OldSize != Data.size(); +} + +bool MCAssembler::layoutSectionOnce(MCAsmLayout &Layout, + MCSectionData &SD) { + MCFragment *FirstInvalidFragment = NULL; + // Scan for fragments that need relaxation. + for (MCSectionData::iterator it2 = SD.begin(), + ie2 = SD.end(); it2 != ie2; ++it2) { + // Check if this is an fragment that needs relaxation. + bool relaxedFrag = false; + switch(it2->getKind()) { + default: + break; + case MCFragment::FT_Inst: + relaxedFrag = relaxInstruction(Layout, *cast(it2)); + break; + case MCFragment::FT_Dwarf: + relaxedFrag = relaxDwarfLineAddr(Layout, + *cast(it2)); + break; + case MCFragment::FT_DwarfFrame: + relaxedFrag = + relaxDwarfCallFrameFragment(Layout, + *cast(it2)); + break; + case MCFragment::FT_LEB: + relaxedFrag = relaxLEB(Layout, *cast(it2)); + break; + } + // Update the layout, and remember that we relaxed. + if (relaxedFrag && !FirstInvalidFragment) + FirstInvalidFragment = it2; + } + if (FirstInvalidFragment) { + Layout.Invalidate(FirstInvalidFragment); + return true; + } + return false; } -bool MCAssembler::LayoutOnce(const MCObjectWriter &Writer, - MCAsmLayout &Layout) { +bool MCAssembler::layoutOnce(MCAsmLayout &Layout) { ++stats::RelaxationSteps; - // Layout the sections in order. - Layout.LayoutFile(); - - // Scan for fragments that need relaxation. bool WasRelaxed = false; for (iterator it = begin(), ie = end(); it != ie; ++it) { MCSectionData &SD = *it; - - for (MCSectionData::iterator it2 = SD.begin(), - ie2 = SD.end(); it2 != ie2; ++it2) { - // Check if this is an fragment that needs relaxation. - switch(it2->getKind()) { - default: - break; - case MCFragment::FT_Inst: - WasRelaxed |= RelaxInstruction(Writer, Layout, - *cast(it2)); - break; - case MCFragment::FT_Org: - WasRelaxed |= RelaxOrg(Writer, Layout, *cast(it2)); - break; - case MCFragment::FT_LEB: - WasRelaxed |= RelaxLEB(Writer, Layout, *cast(it2)); - break; - } - } + while(layoutSectionOnce(Layout, SD)) + WasRelaxed = true; } return WasRelaxed; } -void MCAssembler::FinishLayout(MCAsmLayout &Layout) { - // Lower out any instruction fragments, to simplify the fixup application and - // output. - // - // FIXME-PERF: We don't have to do this, but the assumption is that it is - // cheap (we will mostly end up eliminating fragments and appending on to data - // fragments), so the extra complexity downstream isn't worth it. Evaluate - // this assumption. - for (iterator it = begin(), ie = end(); it != ie; ++it) { - MCSectionData &SD = *it; - - for (MCSectionData::iterator it2 = SD.begin(), - ie2 = SD.end(); it2 != ie2; ++it2) { - MCInstFragment *IF = dyn_cast(it2); - if (!IF) - continue; - - // Create a new data fragment for the instruction. - // - // FIXME-PERF: Reuse previous data fragment if possible. - MCDataFragment *DF = new MCDataFragment(); - SD.getFragmentList().insert(it2, DF); - - // Update the data fragments layout data. - DF->setParent(IF->getParent()); - DF->setAtom(IF->getAtom()); - DF->setLayoutOrder(IF->getLayoutOrder()); - Layout.FragmentReplaced(IF, DF); - - // Copy in the data and the fixups. - DF->getContents().append(IF->getCode().begin(), IF->getCode().end()); - for (unsigned i = 0, e = IF->getFixups().size(); i != e; ++i) - DF->getFixups().push_back(IF->getFixups()[i]); - - // Delete the instruction fragment and update the iterator. - SD.getFragmentList().erase(IF); - it2 = DF; - } +void MCAssembler::finishLayout(MCAsmLayout &Layout) { + // The layout is done. Mark every fragment as valid. + for (unsigned int i = 0, n = Layout.getSectionOrder().size(); i != n; ++i) { + Layout.getFragmentOffset(&*Layout.getSectionOrder()[i]->rbegin()); } } @@ -961,19 +834,18 @@ void MCFragment::dump() { case MCFragment::FT_Inst: OS << "MCInstFragment"; break; case MCFragment::FT_Org: OS << "MCOrgFragment"; break; case MCFragment::FT_Dwarf: OS << "MCDwarfFragment"; break; + case MCFragment::FT_DwarfFrame: OS << "MCDwarfCallFrameFragment"; break; case MCFragment::FT_LEB: OS << "MCLEBFragment"; break; } OS << ""; + << " Offset:" << Offset << ">"; switch (getKind()) { case MCFragment::FT_Align: { const MCAlignFragment *AF = cast(this); if (AF->hasEmitNops()) OS << " (emit nops)"; - if (AF->hasOnlyAlignAddress()) - OS << " (only align section)"; OS << "\n "; OS << " Alignment:" << AF->getAlignment() << " Value:" << AF->getValue() << " ValueSize:" << AF->getValueSize() @@ -1029,6 +901,12 @@ void MCFragment::dump() { << " LineDelta:" << OF->getLineDelta(); break; } + case MCFragment::FT_DwarfFrame: { + const MCDwarfCallFrameFragment *CF = cast(this); + OS << "\n "; + OS << " AddrDelta:" << CF->getAddrDelta(); + break; + } case MCFragment::FT_LEB: { const MCLEBFragment *LF = cast(this); OS << "\n "; @@ -1043,8 +921,7 @@ void MCSectionData::dump() { raw_ostream &OS = llvm::errs(); OS << "dump(); @@ -1086,3 +963,13 @@ void MCAssembler::dump() { } OS << "]>\n"; } + +// anchors for MC*Fragment vtables +void MCDataFragment::anchor() { } +void MCInstFragment::anchor() { } +void MCAlignFragment::anchor() { } +void MCFillFragment::anchor() { } +void MCOrgFragment::anchor() { } +void MCLEBFragment::anchor() { } +void MCDwarfLineAddrFragment::anchor() { } +void MCDwarfCallFrameFragment::anchor() { }