//
//===----------------------------------------------------------------------===//
+#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Support/Debug.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) {
print(dbgs());
}
+static int getDataAlignmentFactor(MCStreamer &streamer) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ int size = asmInfo.getPointerSize();
+ if (asmInfo.getStackGrowthDirection() == TargetFrameInfo::StackGrowsUp)
+ return size;
+ else
+ return -size;
+}
+
+/// EmitFrameMoves - Emit frame instructions to describe the layout of the
+/// frame.
+static void EmitFrameMoves(MCStreamer &streamer,
+ const std::vector<MachineMove> &Moves,
+ MCSymbol *BaseLabel, bool isEH) {
+ MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ int dataAlignmentFactor = getDataAlignmentFactor(streamer);
+
+ for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
+ const MachineMove &Move = Moves[i];
+ MCSymbol *Label = Move.getLabel();
+ // Throw out move if the label is invalid.
+ if (Label && !Label->isDefined()) continue; // Not emitted, in dead code.
+
+ const MachineLocation &Dst = Move.getDestination();
+ const MachineLocation &Src = Move.getSource();
+
+ // Advance row if new location.
+ if (BaseLabel && Label) {
+ MCSymbol *ThisSym = Label;
+ if (ThisSym != BaseLabel) {
+ streamer.EmitIntValue(dwarf::DW_CFA_advance_loc4, 1);
+ const MCExpr *Length = MakeStartMinusEndExpr(streamer, *BaseLabel,
+ *ThisSym, 4);
+ streamer.EmitValue(Length, 4);
+ BaseLabel = ThisSym;
+ }
+ }
+
+ // 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(asmInfo.getDwarfRegNum(Src.getReg(), isEH),
+ 1);
+ }
+
+ streamer.EmitULEB128IntValue(-Src.getOffset(), 1);
+ continue;
+ }
+
+ 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(asmInfo.getDwarfRegNum(Dst.getReg(), isEH));
+ continue;
+ }
+
+ unsigned Reg = asmInfo.getDwarfRegNum(Src.getReg(), isEH);
+ 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);
+ }
+ }
+}
+
+static const MCSymbol &EmitCIE(MCStreamer &streamer) {
+ 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 += "zR";
+ 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);
+ 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();
+
+ EmitFrameMoves(streamer, Moves, NULL, true);
+
+ // Padding
+ streamer.EmitValueToAlignment(asmInfo.getPointerSize());
+
+ streamer.EmitLabel(sectionEnd);
+ return *sectionStart;
+}
+
+static MCSymbol *EmitFDE(MCStreamer &streamer,
+ const MCSymbol &cieStart,
+ const MCDwarfFrameInfo &frame) {
+ MCSymbol *fdeStart = streamer.getContext().CreateTempSymbol();
+ MCSymbol *fdeEnd = streamer.getContext().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
+ streamer.EmitULEB128IntValue(0);
+
+ // Augmentation Data
+ // Call Frame Instructions
+
+ // Padding
+ streamer.EmitValueToAlignment(4);
+
+ return fdeEnd;
+}
+
+void MCDwarfFrameEmitter::Emit(MCStreamer &streamer) {
+ const MCContext &context = streamer.getContext();
+ const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
+ const MCSymbol &cieStart = EmitCIE(streamer);
+ MCSymbol *fdeEnd = NULL;
+ for (unsigned i = 0, n = streamer.getNumFrameInfos(); i < n; ++i) {
+ fdeEnd = EmitFDE(streamer, cieStart, streamer.getFrameInfo(i));
+ if (i != n - 1)
+ streamer.EmitLabel(fdeEnd);
+ }
+ streamer.EmitValueToAlignment(asmInfo.getPointerSize());
+ if (fdeEnd)
+ streamer.EmitLabel(fdeEnd);
+}