//
//===----------------------------------------------------------------------===//
+#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/MCObjectWriter.h"
#include "llvm/ADT/SmallString.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;
}
//
static inline void EmitDwarfLineTable(MCStreamer *MCOS,
const MCSection *Section,
- const MCLineSection *LineSection,
- const MCSection *DwarfLineSection) {
+ const MCLineSection *LineSection) {
unsigned FileNum = 1;
unsigned LastLine = 1;
unsigned Column = 0;
// 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());
MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, LastLabel, SectionEnd);
}
//
// This emits the Dwarf file and the line tables.
//
-void MCDwarfFileTable::Emit(MCStreamer *MCOS,
- const MCSection *DwarfLineSection,
- const MCSection *TextSection) {
+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, true /*UseSet*/);
+ 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, true /*UseSet*/);
+ 4, 0);
// Parameters of the state machine, are next.
MCOS->EmitIntValue(DWARF2_LINE_MIN_INSN_LENGTH, 1);
// 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);
+ EmitDwarfLineTable(MCOS, Sec, Line);
// Now delete the MCLineSections that were created in MCLineEntry::Make()
// and used to emit the line table.
delete Line;
}
- if (TextSection && MCLineSectionOrder.begin() == MCLineSectionOrder.end()) {
- // Emit dummy entry if line table is empty.
-
- MCOS->SwitchSection(TextSection);
- MCSymbol *SectionEnd = MCOS->getContext().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);
+ 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
- MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, NULL, SectionEnd);
+ // 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
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) {
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 void EmitCFIInstruction(MCStreamer &Streamer,
+ const MCCFIInstruction &Instr) {
+ int dataAlignmentFactor = getDataAlignmentFactor(Streamer);
+
+ switch (Instr.getOperation()) {
+ case MCCFIInstruction::Move: {
+ const MachineLocation &Dst = Instr.getDestination();
+ const MachineLocation &Src = Instr.getSource();
+
+ // If advancing cfa.
+ if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
+ assert(!Src.isReg() && "Machine move not supported yet.");
+
+ 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());
+ }
+
+ Streamer.EmitULEB128IntValue(-Src.getOffset(), 1);
+ 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() / 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, 1);
+ } else {
+ Streamer.EmitIntValue(dwarf::DW_CFA_offset_extended, 1);
+ Streamer.EmitULEB128IntValue(Reg, 1);
+ Streamer.EmitULEB128IntValue(Offset, 1);
+ }
+ 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;
+ }
+ llvm_unreachable("Unhandled case in switch");
+}
+
+/// EmitFrameMoves - Emit frame instructions to describe the layout of the
+/// frame.
+static void 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);
+ }
+}
+
+static void EmitSymbol(MCStreamer &streamer, const MCSymbol &symbol,
+ unsigned symbolEncoding) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ unsigned format = symbolEncoding & 0x0f;
+ unsigned application = symbolEncoding & 0x70;
+ unsigned size;
+ switch (format) {
+ default:
+ assert(0 && "Unknown Encoding");
+ case dwarf::DW_EH_PE_absptr:
+ case dwarf::DW_EH_PE_signed:
+ size = asmInfo.getPointerSize();
+ break;
+ case dwarf::DW_EH_PE_udata2:
+ case dwarf::DW_EH_PE_sdata2:
+ size = 2;
+ break;
+ case dwarf::DW_EH_PE_udata4:
+ case dwarf::DW_EH_PE_sdata4:
+ size = 4;
+ break;
+ case dwarf::DW_EH_PE_udata8:
+ case dwarf::DW_EH_PE_sdata8:
+ size = 8;
+ break;
+ }
+ switch (application) {
+ default:
+ assert(0 && "Unknown Encoding");
+ break;
+ case 0:
+ streamer.EmitSymbolValue(&symbol, size);
+ break;
+ case dwarf::DW_EH_PE_pcrel:
+ streamer.EmitPCRelSymbolValue(&symbol, size);
+ break;
+ }
+}
+
+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;
+}
+
+static const MCSymbol &EmitCIE(MCStreamer &streamer,
+ const MCSymbol *personality,
+ unsigned personalityEncoding,
+ const MCSymbol *lsda,
+ unsigned lsdaEncoding) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ const MCSection §ion = *asmInfo.getEHFrameSection();
+ streamer.SwitchSection(§ion);
+ MCSymbol *sectionStart = streamer.getContext().CreateTempSymbol();
+ MCSymbol *sectionEnd = streamer.getContext().CreateTempSymbol();
+
+ // Length
+ const MCExpr *Length = MakeStartMinusEndExpr(streamer, *sectionStart,
+ *sectionEnd, 4);
+ streamer.EmitLabel(sectionStart);
+ streamer.EmitValue(Length, 4);
+
+ // CIE ID
+ streamer.EmitIntValue(0, 4);
+
+ // Version
+ streamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1);
+
+ // Augmentation String
+ SmallString<8> Augmentation;
+ 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)
+ MCSymbol *augmentationStart = streamer.getContext().CreateTempSymbol();
+ MCSymbol *augmentationEnd = streamer.getContext().CreateTempSymbol();
+ const MCExpr *augmentationLength = MakeStartMinusEndExpr(streamer,
+ *augmentationStart,
+ *augmentationEnd, 0);
+ streamer.EmitULEB128Value(augmentationLength);
+
+ // Augmentation Data (optional)
+ streamer.EmitLabel(augmentationStart);
+ if (personality) {
+ // Personality Encoding
+ streamer.EmitIntValue(personalityEncoding, 1);
+ // Personality
+ EmitSymbol(streamer, *personality, personalityEncoding);
+ }
+ if (lsda) {
+ // LSDA Encoding
+ streamer.EmitIntValue(lsdaEncoding, 1);
+ }
+ // Encoding of the FDE pointers
+ streamer.EmitIntValue(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4, 1);
+ streamer.EmitLabel(augmentationEnd);
+
+ // 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(4);
+
+ streamer.EmitLabel(sectionEnd);
+ return *sectionStart;
+}
+
+static MCSymbol *EmitFDE(MCStreamer &streamer,
+ const MCSymbol &cieStart,
+ const MCDwarfFrameInfo &frame) {
+ MCContext &context = streamer.getContext();
+ MCSymbol *fdeStart = context.CreateTempSymbol();
+ MCSymbol *fdeEnd = context.CreateTempSymbol();
+
+ // Length
+ const MCExpr *Length = MakeStartMinusEndExpr(streamer, *fdeStart, *fdeEnd, 0);
+ streamer.EmitValue(Length, 4);
+
+ streamer.EmitLabel(fdeStart);
+ // CIE Pointer
+ const MCExpr *offset = MakeStartMinusEndExpr(streamer, cieStart, *fdeStart,
+ 0);
+ streamer.EmitValue(offset, 4);
+
+ // PC Begin
+ streamer.EmitPCRelSymbolValue(frame.Begin, 4);
+
+ // PC Range
+ const MCExpr *Range = MakeStartMinusEndExpr(streamer, *frame.Begin,
+ *frame.End, 0);
+ streamer.EmitValue(Range, 4);
+
+ // Augmentation Data Length
+ MCSymbol *augmentationStart = streamer.getContext().CreateTempSymbol();
+ MCSymbol *augmentationEnd = streamer.getContext().CreateTempSymbol();
+ const MCExpr *augmentationLength = MakeStartMinusEndExpr(streamer,
+ *augmentationStart,
+ *augmentationEnd, 0);
+ streamer.EmitULEB128Value(augmentationLength);
+
+ // Augmentation Data
+ streamer.EmitLabel(augmentationStart);
+ if (frame.Lsda)
+ EmitSymbol(streamer, *frame.Lsda, frame.LsdaEncoding);
+ streamer.EmitLabel(augmentationEnd);
+ // Call Frame Instructions
+
+ EmitCFIInstructions(streamer, frame.Instructions, frame.Begin);
+
+ // Padding
+ streamer.EmitValueToAlignment(4);
+
+ 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) {
+ const MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ MCSymbol *fdeEnd = NULL;
+ DenseMap<CIEKey, const MCSymbol*> CIEStarts;
+
+ 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 = CIEStarts[key];
+ if (!cieStart)
+ cieStart = &EmitCIE(streamer, frame.Personality,
+ frame.PersonalityEncoding, frame.Lsda,
+ frame.LsdaEncoding);
+ fdeEnd = 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);
+
+ }
+}