//
//===----------------------------------------------------------------------===//
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/ADT/SmallString.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/TargetAsmBackend.h"
+#include "llvm/Target/TargetAsmInfo.h"
using namespace llvm;
// Given a special op, return the address skip amount (in units of
//
// This helper routine returns an expression of End - Start + IntVal .
//
-static inline const MCExpr *MakeStartMinusEndExpr(MCStreamer *MCOS,
- MCSymbol *Start,
- MCSymbol *End, int IntVal) {
+static inline const MCExpr *MakeStartMinusEndExpr(const MCStreamer &MCOS,
+ const MCSymbol &Start,
+ const MCSymbol &End,
+ int IntVal) {
MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
const MCExpr *Res =
- MCSymbolRefExpr::Create(End, Variant, MCOS->getContext());
+ MCSymbolRefExpr::Create(&End, Variant, MCOS.getContext());
const MCExpr *RHS =
- MCSymbolRefExpr::Create(Start, Variant, MCOS->getContext());
+ MCSymbolRefExpr::Create(&Start, Variant, MCOS.getContext());
const MCExpr *Res1 =
- MCBinaryExpr::Create(MCBinaryExpr::Sub, Res, RHS, MCOS->getContext());
+ MCBinaryExpr::Create(MCBinaryExpr::Sub, Res, RHS, MCOS.getContext());
const MCExpr *Res2 =
- MCConstantExpr::Create(IntVal, MCOS->getContext());
+ MCConstantExpr::Create(IntVal, MCOS.getContext());
const MCExpr *Res3 =
- MCBinaryExpr::Create(MCBinaryExpr::Sub, Res1, Res2, MCOS->getContext());
+ MCBinaryExpr::Create(MCBinaryExpr::Sub, Res1, Res2, MCOS.getContext());
return Res3;
}
-//
-// This emits an "absolute" address used in the start of a dwarf line number
-// table. This will result in a relocatation entry for the address.
-//
-static inline void EmitDwarfSetAddress(MCStreamer *MCOS,
- MCSymbol *Symbol,
- int PointerSize) {
- MCOS->EmitIntValue(dwarf::DW_LNS_extended_op, 1);
-
- MCOS->EmitULEB128IntValue(PointerSize + 1);
-
- MCOS->EmitIntValue(dwarf::DW_LNE_set_address, 1);
- MCOS->EmitSymbolValue(Symbol, PointerSize);
-}
-
//
// This emits the Dwarf line table for the specified section from the entries
// in the LineSection.
//
static inline void EmitDwarfLineTable(MCStreamer *MCOS,
const MCSection *Section,
- const MCLineSection *LineSection,
- const MCSection *DwarfLineSection,
- MCSectionData *DLS,
- int PointerSize) {
+ const MCLineSection *LineSection) {
unsigned FileNum = 1;
unsigned LastLine = 1;
unsigned Column = 0;
// At this point we want to emit/create the sequence to encode the delta in
// line numbers and the increment of the address from the previous Label
// and the current Label.
- if (LastLabel == NULL || DLS == NULL) {
- // emit the sequence to set the address
- EmitDwarfSetAddress(MCOS, Label, PointerSize);
- // emit the sequence for the LineDelta (from 1) and a zero address delta.
- MCDwarfLineAddr::Emit(MCOS, LineDelta, 0);
- }
- else {
- // Create an expression for the address delta from the LastLabel and
- // this Label (plus 0).
- const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, Label,0);
- // Create a Dwarf Line fragment for the LineDelta and AddrDelta.
- new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, DLS);
- }
+ MCOS->EmitDwarfAdvanceLineAddr(LineDelta, LastLabel, Label);
LastLine = it->getLine();
LastLabel = Label;
// Switch to the section to be able to create a symbol at its end.
MCOS->SwitchSection(Section);
+
+ MCContext &context = MCOS->getContext();
// Create a symbol at the end of the section.
- MCSymbol *SectionEnd = MCOS->getContext().CreateTempSymbol();
+ MCSymbol *SectionEnd = context.CreateTempSymbol();
// Set the value of the symbol, as we are at the end of the section.
MCOS->EmitLabel(SectionEnd);
// Switch back the the dwarf line section.
- MCOS->SwitchSection(DwarfLineSection);
+ MCOS->SwitchSection(context.getTargetAsmInfo().getDwarfLineSection());
- if (DLS == NULL) {
- // emit the sequence to set the address
- EmitDwarfSetAddress(MCOS, SectionEnd, PointerSize);
- // emit the sequence for the LineDelta (from 1) and a zero address delta.
- MCDwarfLineAddr::Emit(MCOS, INT64_MAX, 0);
- } else {
- // Create an expression for the address delta from the LastLabel and this
- // SectionEnd label.
- const MCExpr *AddrDelta = MakeStartMinusEndExpr(MCOS, LastLabel, SectionEnd,
- 0);
- // Create a Dwarf Line fragment for the LineDelta and AddrDelta.
- new MCDwarfLineAddrFragment(INT64_MAX, *AddrDelta, DLS);
- }
+ MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, LastLabel, SectionEnd);
}
//
// This emits the Dwarf file and the line tables.
//
-void MCDwarfFileTable::Emit(MCStreamer *MCOS,
- const MCSection *DwarfLineSection,
- MCSectionData *DLS,
- int PointerSize) {
+void MCDwarfFileTable::Emit(MCStreamer *MCOS) {
+ MCContext &context = MCOS->getContext();
// Switch to the section where the table will be emitted into.
- MCOS->SwitchSection(DwarfLineSection);
+ MCOS->SwitchSection(context.getTargetAsmInfo().getDwarfLineSection());
// Create a symbol at the beginning of this section.
- MCSymbol *LineStartSym = MCOS->getContext().CreateTempSymbol();
+ MCSymbol *LineStartSym = context.CreateTempSymbol();
// Set the value of the symbol, as we are at the start of the section.
MCOS->EmitLabel(LineStartSym);
// Create a symbol for the end of the section (to be set when we get there).
- MCSymbol *LineEndSym = MCOS->getContext().CreateTempSymbol();
+ MCSymbol *LineEndSym = context.CreateTempSymbol();
// The first 4 bytes is the total length of the information for this
// compilation unit (not including these 4 bytes for the length).
- MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, LineEndSym, 4),
- 4, 0);
+ MCOS->EmitAbsValue(MakeStartMinusEndExpr(*MCOS, *LineStartSym, *LineEndSym,4),
+ 4);
// Next 2 bytes is the Version, which is Dwarf 2.
MCOS->EmitIntValue(2, 2);
// Create a symbol for the end of the prologue (to be set when we get there).
- MCSymbol *ProEndSym = MCOS->getContext().CreateTempSymbol(); // Lprologue_end
+ MCSymbol *ProEndSym = context.CreateTempSymbol(); // Lprologue_end
// Length of the prologue, is the next 4 bytes. Which is the start of the
// section to the end of the prologue. Not including the 4 bytes for the
// total length, the 2 bytes for the version, and these 4 bytes for the
// length of the prologue.
- MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, ProEndSym,
+ MCOS->EmitAbsValue(MakeStartMinusEndExpr(*MCOS, *LineStartSym, *ProEndSym,
(4 + 2 + 4)),
4, 0);
// First the directory table.
const std::vector<StringRef> &MCDwarfDirs =
- MCOS->getContext().getMCDwarfDirs();
+ context.getMCDwarfDirs();
for (unsigned i = 0; i < MCDwarfDirs.size(); i++) {
MCOS->EmitBytes(MCDwarfDirs[i], 0); // the DirectoryName
MCOS->EmitBytes(StringRef("\0", 1), 0); // the null term. of the string
++it) {
const MCSection *Sec = *it;
const MCLineSection *Line = MCLineSections.lookup(Sec);
- EmitDwarfLineTable(MCOS, Sec, Line, DwarfLineSection, DLS,
- PointerSize);
+ EmitDwarfLineTable(MCOS, Sec, Line);
// Now delete the MCLineSections that were created in MCLineEntry::Make()
// and used to emit the line table.
delete Line;
}
+ if (MCOS->getContext().getAsmInfo().getLinkerRequiresNonEmptyDwarfLines()
+ && MCLineSectionOrder.begin() == MCLineSectionOrder.end()) {
+ // The darwin9 linker has a bug (see PR8715). For for 32-bit architectures
+ // it requires:
+ // total_length >= prologue_length + 10
+ // We are 4 bytes short, since we have total_length = 51 and
+ // prologue_length = 45
+
+ // The regular end_sequence should be sufficient.
+ MCDwarfLineAddr::Emit(MCOS, INT64_MAX, 0);
+ }
+
// This is the end of the section, so set the value of the symbol at the end
// of this section (that was used in a previous expression).
MCOS->EmitLabel(LineEndSym);
}
-/// Utility function to compute the size of the encoding.
-uint64_t MCDwarfLineAddr::ComputeSize(int64_t LineDelta, uint64_t AddrDelta) {
- SmallString<256> Tmp;
- raw_svector_ostream OS(Tmp);
- MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OS);
- return OS.GetNumBytesInBuffer();
-}
-
/// Utility function to write the encoding to an object writer.
void MCDwarfLineAddr::Write(MCObjectWriter *OW, int64_t LineDelta,
uint64_t AddrDelta) {
OS << char(dwarf::DW_LNS_const_add_pc);
else {
OS << char(dwarf::DW_LNS_advance_pc);
- SmallString<32> Tmp;
- raw_svector_ostream OSE(Tmp);
- MCObjectWriter::EncodeULEB128(AddrDelta, OSE);
- OS << OSE.str();
+ MCObjectWriter::EncodeULEB128(AddrDelta, OS);
}
OS << char(dwarf::DW_LNS_extended_op);
OS << char(1);
print(dbgs());
}
+static int getDataAlignmentFactor(MCStreamer &streamer) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ int size = asmInfo.getPointerSize();
+ if (asmInfo.getStackGrowthDirection() == TargetFrameLowering::StackGrowsUp)
+ return size;
+ else
+ return -size;
+}
+
+static unsigned getSizeForEncoding(MCStreamer &streamer,
+ unsigned symbolEncoding) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ unsigned format = symbolEncoding & 0x0f;
+ switch (format) {
+ default:
+ assert(0 && "Unknown Encoding");
+ case dwarf::DW_EH_PE_absptr:
+ case dwarf::DW_EH_PE_signed:
+ return asmInfo.getPointerSize();
+ case dwarf::DW_EH_PE_udata2:
+ case dwarf::DW_EH_PE_sdata2:
+ return 2;
+ case dwarf::DW_EH_PE_udata4:
+ case dwarf::DW_EH_PE_sdata4:
+ return 4;
+ case dwarf::DW_EH_PE_udata8:
+ case dwarf::DW_EH_PE_sdata8:
+ return 8;
+ }
+}
+
+static void EmitSymbol(MCStreamer &streamer, const MCSymbol &symbol,
+ unsigned symbolEncoding) {
+ MCContext &context = streamer.getContext();
+ const MCAsmInfo &asmInfo = context.getAsmInfo();
+ const MCExpr *v = asmInfo.getExprForFDESymbol(&symbol,
+ symbolEncoding,
+ streamer);
+ unsigned size = getSizeForEncoding(streamer, symbolEncoding);
+ streamer.EmitAbsValue(v, size);
+}
+
+static void EmitPersonality(MCStreamer &streamer, const MCSymbol &symbol,
+ unsigned symbolEncoding) {
+ MCContext &context = streamer.getContext();
+ const MCAsmInfo &asmInfo = context.getAsmInfo();
+ const MCExpr *v = asmInfo.getExprForPersonalitySymbol(&symbol,
+ symbolEncoding,
+ streamer);
+ unsigned size = getSizeForEncoding(streamer, symbolEncoding);
+ streamer.EmitValue(v, size);
+}
+
+static const MachineLocation TranslateMachineLocation(
+ const TargetAsmInfo &AsmInfo,
+ const MachineLocation &Loc) {
+ unsigned Reg = Loc.getReg() == MachineLocation::VirtualFP ?
+ MachineLocation::VirtualFP :
+ unsigned(AsmInfo.getDwarfRegNum(Loc.getReg(), true));
+ const MachineLocation &NewLoc = Loc.isReg() ?
+ MachineLocation(Reg) : MachineLocation(Reg, Loc.getOffset());
+ return NewLoc;
+}
+
+namespace {
+ class FrameEmitterImpl {
+ int CFAOffset;
+ int CIENum;
+ bool UsingCFI;
+ bool IsEH;
+ const MCSymbol *SectionStart;
+
+ public:
+ FrameEmitterImpl(bool usingCFI, bool isEH, const MCSymbol *sectionStart) :
+ CFAOffset(0), CIENum(0), UsingCFI(usingCFI), IsEH(isEH),
+ SectionStart(sectionStart) {
+ }
+
+ /// EmitCompactUnwind - Emit the unwind information in a compact way. If
+ /// we're successful, return 'true'. Otherwise, return 'false' and it will
+ /// emit the normal CIE and FDE.
+ bool EmitCompactUnwind(MCStreamer &streamer,
+ const MCDwarfFrameInfo &frame);
+
+ const MCSymbol &EmitCIE(MCStreamer &streamer,
+ const MCSymbol *personality,
+ unsigned personalityEncoding,
+ const MCSymbol *lsda,
+ unsigned lsdaEncoding);
+ MCSymbol *EmitFDE(MCStreamer &streamer,
+ const MCSymbol &cieStart,
+ const MCDwarfFrameInfo &frame);
+ void EmitCFIInstructions(MCStreamer &streamer,
+ const std::vector<MCCFIInstruction> &Instrs,
+ MCSymbol *BaseLabel);
+ void EmitCFIInstruction(MCStreamer &Streamer,
+ const MCCFIInstruction &Instr);
+ };
+}
+
+void FrameEmitterImpl::EmitCFIInstruction(MCStreamer &Streamer,
+ const MCCFIInstruction &Instr) {
+ int dataAlignmentFactor = getDataAlignmentFactor(Streamer);
+
+ switch (Instr.getOperation()) {
+ case MCCFIInstruction::Move:
+ case MCCFIInstruction::RelMove: {
+ const MachineLocation &Dst = Instr.getDestination();
+ const MachineLocation &Src = Instr.getSource();
+ const bool IsRelative = Instr.getOperation() == MCCFIInstruction::RelMove;
+
+ // If advancing cfa.
+ if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
+ if (Src.getReg() == MachineLocation::VirtualFP) {
+ Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_offset, 1);
+ } else {
+ Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa, 1);
+ Streamer.EmitULEB128IntValue(Src.getReg());
+ }
+
+ if (IsRelative)
+ CFAOffset += Src.getOffset();
+ else
+ CFAOffset = -Src.getOffset();
+
+ Streamer.EmitULEB128IntValue(CFAOffset);
+ return;
+ }
+
+ if (Src.isReg() && Src.getReg() == MachineLocation::VirtualFP) {
+ assert(Dst.isReg() && "Machine move not supported yet.");
+ Streamer.EmitIntValue(dwarf::DW_CFA_def_cfa_register, 1);
+ Streamer.EmitULEB128IntValue(Dst.getReg());
+ return;
+ }
+
+ unsigned Reg = Src.getReg();
+
+ int Offset = Dst.getOffset();
+ if (IsRelative)
+ Offset -= CFAOffset;
+ Offset = Offset / dataAlignmentFactor;
+
+ if (Offset < 0) {
+ Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended_sf, 1);
+ Streamer.EmitULEB128IntValue(Reg);
+ Streamer.EmitSLEB128IntValue(Offset);
+ } else if (Reg < 64) {
+ Streamer.EmitIntValue(dwarf::DW_CFA_offset + Reg, 1);
+ Streamer.EmitULEB128IntValue(Offset);
+ } else {
+ Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended, 1);
+ Streamer.EmitULEB128IntValue(Reg);
+ Streamer.EmitULEB128IntValue(Offset);
+ }
+ return;
+ }
+ case MCCFIInstruction::Remember:
+ Streamer.EmitIntValue(dwarf::DW_CFA_remember_state, 1);
+ return;
+ case MCCFIInstruction::Restore:
+ Streamer.EmitIntValue(dwarf::DW_CFA_restore_state, 1);
+ return;
+ case MCCFIInstruction::SameValue: {
+ unsigned Reg = Instr.getDestination().getReg();
+ Streamer.EmitIntValue(dwarf::DW_CFA_same_value, 1);
+ Streamer.EmitULEB128IntValue(Reg);
+ return;
+ }
+ }
+ llvm_unreachable("Unhandled case in switch");
+}
+
+/// EmitFrameMoves - Emit frame instructions to describe the layout of the
+/// frame.
+void FrameEmitterImpl::EmitCFIInstructions(MCStreamer &streamer,
+ const std::vector<MCCFIInstruction> &Instrs,
+ MCSymbol *BaseLabel) {
+ for (unsigned i = 0, N = Instrs.size(); i < N; ++i) {
+ const MCCFIInstruction &Instr = Instrs[i];
+ MCSymbol *Label = Instr.getLabel();
+ // Throw out move if the label is invalid.
+ if (Label && !Label->isDefined()) continue; // Not emitted, in dead code.
+
+ // Advance row if new location.
+ if (BaseLabel && Label) {
+ MCSymbol *ThisSym = Label;
+ if (ThisSym != BaseLabel) {
+ streamer.EmitDwarfAdvanceFrameAddr(BaseLabel, ThisSym);
+ BaseLabel = ThisSym;
+ }
+ }
+
+ EmitCFIInstruction(streamer, Instr);
+ }
+}
+
+/// EmitCompactUnwind - Emit the unwind information in a compact way. If we're
+/// successful, return 'true'. Otherwise, return 'false' and it will emit the
+/// normal CIE and FDE.
+bool FrameEmitterImpl::EmitCompactUnwind(MCStreamer &Streamer,
+ const MCDwarfFrameInfo &Frame) {
+#if 1
+ return false;
+#else
+ MCContext &Context = Streamer.getContext();
+ const TargetAsmInfo &TAI = Context.getTargetAsmInfo();
+ Streamer.SwitchSection(TAI.getCompactUnwindSection());
+
+ unsigned FDEEncoding = TAI.getFDEEncoding(UsingCFI);
+ unsigned Size = getSizeForEncoding(Streamer, FDEEncoding);
+
+ // range-start range-length compact-unwind-enc personality-func lsda
+ // _foo LfooEnd-_foo 0x00000023 0 0
+ // _bar LbarEnd-_bar 0x00000025 __gxx_personality except_tab1
+ //
+ // .section __LD,__compact_unwind,regular,debug
+ //
+ // # compact unwind for _foo
+ // .quad _foo
+ // .set L1,LfooEnd-_foo
+ // .long L1
+ // .long 0x01010001
+ // .quad 0
+ // .quad 0
+ //
+ // # compact unwind for _bar
+ // .quad _bar
+ // .set L2,LbarEnd-_bar
+ // .long L2
+ // .long 0x01020011
+ // .quad __gxx_personality
+ // .quad except_tab1
+
+ // Range Start
+ EmitSymbol(Streamer, *Frame.Begin, FDEEncoding);
+
+ // Range Length
+ const MCExpr *Range = MakeStartMinusEndExpr(Streamer, *Frame.Begin,
+ *Frame.End, 0);
+ Streamer.EmitAbsValue(Range, Size);
+
+ return true;
+#endif
+}
+
+const MCSymbol &FrameEmitterImpl::EmitCIE(MCStreamer &streamer,
+ const MCSymbol *personality,
+ unsigned personalityEncoding,
+ const MCSymbol *lsda,
+ unsigned lsdaEncoding) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+
+ MCSymbol *sectionStart;
+ if (asmInfo.isFunctionEHFrameSymbolPrivate() || !IsEH)
+ sectionStart = context.CreateTempSymbol();
+ else
+ sectionStart = context.GetOrCreateSymbol(Twine("EH_frame") + Twine(CIENum));
+
+ CIENum++;
+
+ MCSymbol *sectionEnd = streamer.getContext().CreateTempSymbol();
+
+ // Length
+ const MCExpr *Length = MakeStartMinusEndExpr(streamer, *sectionStart,
+ *sectionEnd, 4);
+ streamer.EmitLabel(sectionStart);
+ streamer.EmitAbsValue(Length, 4);
+
+ // CIE ID
+ unsigned CIE_ID = IsEH ? 0 : -1;
+ streamer.EmitIntValue(CIE_ID, 4);
+
+ // Version
+ streamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1);
+
+ // Augmentation String
+ SmallString<8> Augmentation;
+ if (IsEH) {
+ Augmentation += "z";
+ if (personality)
+ Augmentation += "P";
+ if (lsda)
+ Augmentation += "L";
+ Augmentation += "R";
+ streamer.EmitBytes(Augmentation.str(), 0);
+ }
+ streamer.EmitIntValue(0, 1);
+
+ // Code Alignment Factor
+ streamer.EmitULEB128IntValue(1);
+
+ // Data Alignment Factor
+ streamer.EmitSLEB128IntValue(getDataAlignmentFactor(streamer));
+
+ // Return Address Register
+ streamer.EmitULEB128IntValue(asmInfo.getDwarfRARegNum(true));
+
+ // Augmentation Data Length (optional)
+
+ unsigned augmentationLength = 0;
+ if (IsEH) {
+ if (personality) {
+ // Personality Encoding
+ augmentationLength += 1;
+ // Personality
+ augmentationLength += getSizeForEncoding(streamer, personalityEncoding);
+ }
+ if (lsda)
+ augmentationLength += 1;
+ // Encoding of the FDE pointers
+ augmentationLength += 1;
+
+ streamer.EmitULEB128IntValue(augmentationLength);
+
+ // Augmentation Data (optional)
+ if (personality) {
+ // Personality Encoding
+ streamer.EmitIntValue(personalityEncoding, 1);
+ // Personality
+ EmitPersonality(streamer, *personality, personalityEncoding);
+ }
+ if (lsda)
+ streamer.EmitIntValue(lsdaEncoding, 1); // LSDA Encoding
+ // Encoding of the FDE pointers
+ streamer.EmitIntValue(asmInfo.getFDEEncoding(UsingCFI), 1);
+ }
+
+ // Initial Instructions
+
+ const std::vector<MachineMove> Moves = asmInfo.getInitialFrameState();
+ std::vector<MCCFIInstruction> Instructions;
+
+ for (int i = 0, n = Moves.size(); i != n; ++i) {
+ MCSymbol *Label = Moves[i].getLabel();
+ const MachineLocation &Dst =
+ TranslateMachineLocation(asmInfo, Moves[i].getDestination());
+ const MachineLocation &Src =
+ TranslateMachineLocation(asmInfo, Moves[i].getSource());
+ MCCFIInstruction Inst(Label, Dst, Src);
+ Instructions.push_back(Inst);
+ }
+
+ EmitCFIInstructions(streamer, Instructions, NULL);
+
+ // Padding
+ streamer.EmitValueToAlignment(IsEH ? 4 : asmInfo.getPointerSize());
+
+ streamer.EmitLabel(sectionEnd);
+ return *sectionStart;
+}
+
+MCSymbol *FrameEmitterImpl::EmitFDE(MCStreamer &streamer,
+ const MCSymbol &cieStart,
+ const MCDwarfFrameInfo &frame) {
+ MCContext &context = streamer.getContext();
+ MCSymbol *fdeStart = context.CreateTempSymbol();
+ MCSymbol *fdeEnd = context.CreateTempSymbol();
+ const TargetAsmInfo &TAsmInfo = context.getTargetAsmInfo();
+
+ if (!TAsmInfo.isFunctionEHFrameSymbolPrivate() && IsEH) {
+ MCSymbol *EHSym = context.GetOrCreateSymbol(
+ frame.Function->getName() + Twine(".eh"));
+ streamer.EmitEHSymAttributes(frame.Function, EHSym);
+ streamer.EmitLabel(EHSym);
+ }
+
+ // Length
+ const MCExpr *Length = MakeStartMinusEndExpr(streamer, *fdeStart, *fdeEnd, 0);
+ streamer.EmitAbsValue(Length, 4);
+
+ streamer.EmitLabel(fdeStart);
+
+ // CIE Pointer
+ const MCAsmInfo &asmInfo = context.getAsmInfo();
+ if (IsEH) {
+ const MCExpr *offset = MakeStartMinusEndExpr(streamer, cieStart, *fdeStart,
+ 0);
+ streamer.EmitAbsValue(offset, 4);
+ } else if (!asmInfo.doesDwarfRequireRelocationForSectionOffset()) {
+ const MCExpr *offset = MakeStartMinusEndExpr(streamer, *SectionStart,
+ cieStart, 0);
+ streamer.EmitAbsValue(offset, 4);
+ } else {
+ streamer.EmitSymbolValue(&cieStart, 4);
+ }
+ unsigned fdeEncoding = TAsmInfo.getFDEEncoding(UsingCFI);
+ unsigned size = getSizeForEncoding(streamer, fdeEncoding);
+
+ // PC Begin
+ unsigned PCBeginEncoding = IsEH ? fdeEncoding :
+ (unsigned)dwarf::DW_EH_PE_absptr;
+ unsigned PCBeginSize = getSizeForEncoding(streamer, PCBeginEncoding);
+ EmitSymbol(streamer, *frame.Begin, PCBeginEncoding);
+
+ // PC Range
+ const MCExpr *Range = MakeStartMinusEndExpr(streamer, *frame.Begin,
+ *frame.End, 0);
+ streamer.EmitAbsValue(Range, size);
+
+ if (IsEH) {
+ // Augmentation Data Length
+ unsigned augmentationLength = 0;
+
+ if (frame.Lsda)
+ augmentationLength += getSizeForEncoding(streamer, frame.LsdaEncoding);
+
+ streamer.EmitULEB128IntValue(augmentationLength);
+
+ // Augmentation Data
+ if (frame.Lsda)
+ EmitSymbol(streamer, *frame.Lsda, frame.LsdaEncoding);
+ }
+
+ // Call Frame Instructions
+
+ EmitCFIInstructions(streamer, frame.Instructions, frame.Begin);
+
+ // Padding
+ streamer.EmitValueToAlignment(PCBeginSize);
+
+ return fdeEnd;
+}
+
+namespace {
+ struct CIEKey {
+ static const CIEKey getEmptyKey() { return CIEKey(0, 0, -1); }
+ static const CIEKey getTombstoneKey() { return CIEKey(0, -1, 0); }
+
+ CIEKey(const MCSymbol* Personality_, unsigned PersonalityEncoding_,
+ unsigned LsdaEncoding_) : Personality(Personality_),
+ PersonalityEncoding(PersonalityEncoding_),
+ LsdaEncoding(LsdaEncoding_) {
+ }
+ const MCSymbol* Personality;
+ unsigned PersonalityEncoding;
+ unsigned LsdaEncoding;
+ };
+}
+
+namespace llvm {
+ template <>
+ struct DenseMapInfo<CIEKey> {
+ static CIEKey getEmptyKey() {
+ return CIEKey::getEmptyKey();
+ }
+ static CIEKey getTombstoneKey() {
+ return CIEKey::getTombstoneKey();
+ }
+ static unsigned getHashValue(const CIEKey &Key) {
+ FoldingSetNodeID ID;
+ ID.AddPointer(Key.Personality);
+ ID.AddInteger(Key.PersonalityEncoding);
+ ID.AddInteger(Key.LsdaEncoding);
+ return ID.ComputeHash();
+ }
+ static bool isEqual(const CIEKey &LHS,
+ const CIEKey &RHS) {
+ return LHS.Personality == RHS.Personality &&
+ LHS.PersonalityEncoding == RHS.PersonalityEncoding &&
+ LHS.LsdaEncoding == RHS.LsdaEncoding;
+ }
+ };
+}
+
+void MCDwarfFrameEmitter::Emit(MCStreamer &streamer,
+ bool usingCFI,
+ bool isEH) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ const MCSection §ion = isEH ?
+ *asmInfo.getEHFrameSection() :
+ *asmInfo.getDwarfFrameSection();
+ streamer.SwitchSection(§ion);
+ MCSymbol *SectionStart = context.CreateTempSymbol();
+ streamer.EmitLabel(SectionStart);
+
+ MCSymbol *fdeEnd = NULL;
+ DenseMap<CIEKey, const MCSymbol*> CIEStarts;
+ FrameEmitterImpl Emitter(usingCFI, isEH, SectionStart);
+
+ const MCSymbol *DummyDebugKey = NULL;
+ for (unsigned i = 0, n = streamer.getNumFrameInfos(); i < n; ++i) {
+ const MCDwarfFrameInfo &frame = streamer.getFrameInfo(i);
+ CIEKey key(frame.Personality, frame.PersonalityEncoding,
+ frame.LsdaEncoding);
+ const MCSymbol *&cieStart = isEH ? CIEStarts[key] : DummyDebugKey;
+ if (isEH && asmInfo.getSupportsCompactUnwindInfo() &&
+ Emitter.EmitCompactUnwind(streamer, frame))
+ continue;
+
+ if (!cieStart)
+ cieStart = &Emitter.EmitCIE(streamer, frame.Personality,
+ frame.PersonalityEncoding, frame.Lsda,
+ frame.LsdaEncoding);
+
+ fdeEnd = Emitter.EmitFDE(streamer, *cieStart, frame);
+
+ if (i != n - 1)
+ streamer.EmitLabel(fdeEnd);
+ }
+
+ streamer.EmitValueToAlignment(asmInfo.getPointerSize());
+ if (fdeEnd)
+ streamer.EmitLabel(fdeEnd);
+}
+
+void MCDwarfFrameEmitter::EmitAdvanceLoc(MCStreamer &Streamer,
+ uint64_t AddrDelta) {
+ SmallString<256> Tmp;
+ raw_svector_ostream OS(Tmp);
+ MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OS);
+ Streamer.EmitBytes(OS.str(), /*AddrSpace=*/0);
+}
+
+void MCDwarfFrameEmitter::EncodeAdvanceLoc(uint64_t AddrDelta,
+ raw_ostream &OS) {
+ // FIXME: Assumes the code alignment factor is 1.
+ if (AddrDelta == 0) {
+ } else if (isUIntN(6, AddrDelta)) {
+ uint8_t Opcode = dwarf::DW_CFA_advance_loc | AddrDelta;
+ OS << Opcode;
+ } else if (isUInt<8>(AddrDelta)) {
+ OS << uint8_t(dwarf::DW_CFA_advance_loc1);
+ OS << uint8_t(AddrDelta);
+ } else if (isUInt<16>(AddrDelta)) {
+ // FIXME: check what is the correct behavior on a big endian machine.
+ OS << uint8_t(dwarf::DW_CFA_advance_loc2);
+ OS << uint8_t( AddrDelta & 0xff);
+ OS << uint8_t((AddrDelta >> 8) & 0xff);
+ } else {
+ // FIXME: check what is the correct behavior on a big endian machine.
+ assert(isUInt<32>(AddrDelta));
+ OS << uint8_t(dwarf::DW_CFA_advance_loc4);
+ OS << uint8_t( AddrDelta & 0xff);
+ OS << uint8_t((AddrDelta >> 8) & 0xff);
+ OS << uint8_t((AddrDelta >> 16) & 0xff);
+ OS << uint8_t((AddrDelta >> 24) & 0xff);
+
+ }
+}