333 lines
11 KiB
C++
333 lines
11 KiB
C++
|
//===-- AsmPrinterDwarf.cpp - AsmPrinter Dwarf Support --------------------===//
|
||
|
|
//
|
||
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
||
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
||
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
||
|
|
//
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
//
|
||
|
|
// This file implements the Dwarf emissions parts of AsmPrinter.
|
||
|
|
//
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
|
||
|
|
#include "ByteStreamer.h"
|
||
|
|
#include "llvm/ADT/Twine.h"
|
||
|
|
#include "llvm/BinaryFormat/Dwarf.h"
|
||
|
|
#include "llvm/CodeGen/AsmPrinter.h"
|
||
|
|
#include "llvm/CodeGen/DIE.h"
|
||
|
|
#include "llvm/CodeGen/MachineFunction.h"
|
||
|
|
#include "llvm/IR/DataLayout.h"
|
||
|
|
#include "llvm/MC/MCAsmInfo.h"
|
||
|
|
#include "llvm/MC/MCDwarf.h"
|
||
|
|
#include "llvm/MC/MCRegisterInfo.h"
|
||
|
|
#include "llvm/MC/MCSection.h"
|
||
|
|
#include "llvm/MC/MCStreamer.h"
|
||
|
|
#include "llvm/MC/MCSymbol.h"
|
||
|
|
#include "llvm/MC/MachineLocation.h"
|
||
|
|
#include "llvm/Support/ErrorHandling.h"
|
||
|
|
#include "llvm/Target/TargetLoweringObjectFile.h"
|
||
|
|
#include "llvm/Target/TargetMachine.h"
|
||
|
|
#include <cstdint>
|
||
|
|
using namespace llvm;
|
||
|
|
|
||
|
|
#define DEBUG_TYPE "asm-printer"
|
||
|
|
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
// Dwarf Emission Helper Routines
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
|
||
|
|
/// EmitSLEB128 - emit the specified signed leb128 value.
|
||
|
|
void AsmPrinter::emitSLEB128(int64_t Value, const char *Desc) const {
|
||
|
|
if (isVerbose() && Desc)
|
||
|
|
OutStreamer->AddComment(Desc);
|
||
|
|
|
||
|
|
OutStreamer->emitSLEB128IntValue(Value);
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitULEB128(uint64_t Value, const char *Desc,
|
||
|
|
unsigned PadTo) const {
|
||
|
|
if (isVerbose() && Desc)
|
||
|
|
OutStreamer->AddComment(Desc);
|
||
|
|
|
||
|
|
OutStreamer->emitULEB128IntValue(Value, PadTo);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// Emit something like ".uleb128 Hi-Lo".
|
||
|
|
void AsmPrinter::emitLabelDifferenceAsULEB128(const MCSymbol *Hi,
|
||
|
|
const MCSymbol *Lo) const {
|
||
|
|
OutStreamer->emitAbsoluteSymbolDiffAsULEB128(Hi, Lo);
|
||
|
|
}
|
||
|
|
|
||
|
|
static const char *DecodeDWARFEncoding(unsigned Encoding) {
|
||
|
|
switch (Encoding) {
|
||
|
|
case dwarf::DW_EH_PE_absptr:
|
||
|
|
return "absptr";
|
||
|
|
case dwarf::DW_EH_PE_omit:
|
||
|
|
return "omit";
|
||
|
|
case dwarf::DW_EH_PE_pcrel:
|
||
|
|
return "pcrel";
|
||
|
|
case dwarf::DW_EH_PE_uleb128:
|
||
|
|
return "uleb128";
|
||
|
|
case dwarf::DW_EH_PE_sleb128:
|
||
|
|
return "sleb128";
|
||
|
|
case dwarf::DW_EH_PE_udata4:
|
||
|
|
return "udata4";
|
||
|
|
case dwarf::DW_EH_PE_udata8:
|
||
|
|
return "udata8";
|
||
|
|
case dwarf::DW_EH_PE_sdata4:
|
||
|
|
return "sdata4";
|
||
|
|
case dwarf::DW_EH_PE_sdata8:
|
||
|
|
return "sdata8";
|
||
|
|
case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4:
|
||
|
|
return "pcrel udata4";
|
||
|
|
case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4:
|
||
|
|
return "pcrel sdata4";
|
||
|
|
case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8:
|
||
|
|
return "pcrel udata8";
|
||
|
|
case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8:
|
||
|
|
return "pcrel sdata8";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4
|
||
|
|
:
|
||
|
|
return "indirect pcrel udata4";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
|
||
|
|
:
|
||
|
|
return "indirect pcrel sdata4";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8
|
||
|
|
:
|
||
|
|
return "indirect pcrel udata8";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8
|
||
|
|
:
|
||
|
|
return "indirect pcrel sdata8";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_datarel |
|
||
|
|
dwarf::DW_EH_PE_sdata4:
|
||
|
|
return "indirect datarel sdata4";
|
||
|
|
case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_datarel |
|
||
|
|
dwarf::DW_EH_PE_sdata8:
|
||
|
|
return "indirect datarel sdata8";
|
||
|
|
}
|
||
|
|
|
||
|
|
return "<unknown encoding>";
|
||
|
|
}
|
||
|
|
|
||
|
|
/// EmitEncodingByte - Emit a .byte 42 directive that corresponds to an
|
||
|
|
/// encoding. If verbose assembly output is enabled, we output comments
|
||
|
|
/// describing the encoding. Desc is an optional string saying what the
|
||
|
|
/// encoding is specifying (e.g. "LSDA").
|
||
|
|
void AsmPrinter::emitEncodingByte(unsigned Val, const char *Desc) const {
|
||
|
|
if (isVerbose()) {
|
||
|
|
if (Desc)
|
||
|
|
OutStreamer->AddComment(Twine(Desc) + " Encoding = " +
|
||
|
|
Twine(DecodeDWARFEncoding(Val)));
|
||
|
|
else
|
||
|
|
OutStreamer->AddComment(Twine("Encoding = ") + DecodeDWARFEncoding(Val));
|
||
|
|
}
|
||
|
|
|
||
|
|
OutStreamer->emitIntValue(Val, 1);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// GetSizeOfEncodedValue - Return the size of the encoding in bytes.
|
||
|
|
unsigned AsmPrinter::GetSizeOfEncodedValue(unsigned Encoding) const {
|
||
|
|
if (Encoding == dwarf::DW_EH_PE_omit)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
switch (Encoding & 0x07) {
|
||
|
|
default:
|
||
|
|
llvm_unreachable("Invalid encoded value.");
|
||
|
|
case dwarf::DW_EH_PE_absptr:
|
||
|
|
return MF->getDataLayout().getPointerSize();
|
||
|
|
case dwarf::DW_EH_PE_udata2:
|
||
|
|
return 2;
|
||
|
|
case dwarf::DW_EH_PE_udata4:
|
||
|
|
return 4;
|
||
|
|
case dwarf::DW_EH_PE_udata8:
|
||
|
|
return 8;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitTTypeReference(const GlobalValue *GV, unsigned Encoding) {
|
||
|
|
if (GV) {
|
||
|
|
const TargetLoweringObjectFile &TLOF = getObjFileLowering();
|
||
|
|
|
||
|
|
const MCExpr *Exp =
|
||
|
|
TLOF.getTTypeGlobalReference(GV, Encoding, TM, MMI, *OutStreamer);
|
||
|
|
OutStreamer->emitValue(Exp, GetSizeOfEncodedValue(Encoding));
|
||
|
|
} else
|
||
|
|
OutStreamer->emitIntValue(0, GetSizeOfEncodedValue(Encoding));
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfSymbolReference(const MCSymbol *Label,
|
||
|
|
bool ForceOffset) const {
|
||
|
|
if (!ForceOffset) {
|
||
|
|
// On COFF targets, we have to emit the special .secrel32 directive.
|
||
|
|
if (MAI->needsDwarfSectionOffsetDirective()) {
|
||
|
|
assert(!isDwarf64() &&
|
||
|
|
"emitting DWARF64 is not implemented for COFF targets");
|
||
|
|
OutStreamer->EmitCOFFSecRel32(Label, /*Offset=*/0);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
// If the format uses relocations with dwarf, refer to the symbol directly.
|
||
|
|
if (MAI->doesDwarfUseRelocationsAcrossSections()) {
|
||
|
|
OutStreamer->emitSymbolValue(Label, getDwarfOffsetByteSize());
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Otherwise, emit it as a label difference from the start of the section.
|
||
|
|
emitLabelDifference(Label, Label->getSection().getBeginSymbol(),
|
||
|
|
getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfStringOffset(DwarfStringPoolEntry S) const {
|
||
|
|
if (MAI->doesDwarfUseRelocationsAcrossSections()) {
|
||
|
|
assert(S.Symbol && "No symbol available");
|
||
|
|
emitDwarfSymbolReference(S.Symbol);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Just emit the offset directly; no need for symbol math.
|
||
|
|
OutStreamer->emitIntValue(S.Offset, getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfOffset(const MCSymbol *Label, uint64_t Offset) const {
|
||
|
|
emitLabelPlusOffset(Label, Offset, getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfLengthOrOffset(uint64_t Value) const {
|
||
|
|
assert(isDwarf64() || Value <= UINT32_MAX);
|
||
|
|
OutStreamer->emitIntValue(Value, getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::maybeEmitDwarf64Mark() const {
|
||
|
|
if (!isDwarf64())
|
||
|
|
return;
|
||
|
|
OutStreamer->AddComment("DWARF64 Mark");
|
||
|
|
OutStreamer->emitInt32(dwarf::DW_LENGTH_DWARF64);
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfUnitLength(uint64_t Length,
|
||
|
|
const Twine &Comment) const {
|
||
|
|
assert(isDwarf64() || Length <= dwarf::DW_LENGTH_lo_reserved);
|
||
|
|
maybeEmitDwarf64Mark();
|
||
|
|
OutStreamer->AddComment(Comment);
|
||
|
|
OutStreamer->emitIntValue(Length, getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfUnitLength(const MCSymbol *Hi, const MCSymbol *Lo,
|
||
|
|
const Twine &Comment) const {
|
||
|
|
maybeEmitDwarf64Mark();
|
||
|
|
OutStreamer->AddComment(Comment);
|
||
|
|
OutStreamer->emitAbsoluteSymbolDiff(Hi, Lo, getDwarfOffsetByteSize());
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitCallSiteOffset(const MCSymbol *Hi, const MCSymbol *Lo,
|
||
|
|
unsigned Encoding) const {
|
||
|
|
// The least significant 3 bits specify the width of the encoding
|
||
|
|
if ((Encoding & 0x7) == dwarf::DW_EH_PE_uleb128)
|
||
|
|
emitLabelDifferenceAsULEB128(Hi, Lo);
|
||
|
|
else
|
||
|
|
emitLabelDifference(Hi, Lo, GetSizeOfEncodedValue(Encoding));
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitCallSiteValue(uint64_t Value, unsigned Encoding) const {
|
||
|
|
// The least significant 3 bits specify the width of the encoding
|
||
|
|
if ((Encoding & 0x7) == dwarf::DW_EH_PE_uleb128)
|
||
|
|
emitULEB128(Value);
|
||
|
|
else
|
||
|
|
OutStreamer->emitIntValue(Value, GetSizeOfEncodedValue(Encoding));
|
||
|
|
}
|
||
|
|
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
// Dwarf Lowering Routines
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
|
||
|
|
void AsmPrinter::emitCFIInstruction(const MCCFIInstruction &Inst) const {
|
||
|
|
switch (Inst.getOperation()) {
|
||
|
|
default:
|
||
|
|
llvm_unreachable("Unexpected instruction");
|
||
|
|
case MCCFIInstruction::OpDefCfaOffset:
|
||
|
|
OutStreamer->emitCFIDefCfaOffset(Inst.getOffset());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpAdjustCfaOffset:
|
||
|
|
OutStreamer->emitCFIAdjustCfaOffset(Inst.getOffset());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpDefCfa:
|
||
|
|
OutStreamer->emitCFIDefCfa(Inst.getRegister(), Inst.getOffset());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpDefCfaRegister:
|
||
|
|
OutStreamer->emitCFIDefCfaRegister(Inst.getRegister());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpOffset:
|
||
|
|
OutStreamer->emitCFIOffset(Inst.getRegister(), Inst.getOffset());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpRegister:
|
||
|
|
OutStreamer->emitCFIRegister(Inst.getRegister(), Inst.getRegister2());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpWindowSave:
|
||
|
|
OutStreamer->emitCFIWindowSave();
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpNegateRAState:
|
||
|
|
OutStreamer->emitCFINegateRAState();
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpSameValue:
|
||
|
|
OutStreamer->emitCFISameValue(Inst.getRegister());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpGnuArgsSize:
|
||
|
|
OutStreamer->emitCFIGnuArgsSize(Inst.getOffset());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpEscape:
|
||
|
|
OutStreamer->AddComment(Inst.getComment());
|
||
|
|
OutStreamer->emitCFIEscape(Inst.getValues());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpRestore:
|
||
|
|
OutStreamer->emitCFIRestore(Inst.getRegister());
|
||
|
|
break;
|
||
|
|
case MCCFIInstruction::OpUndefined:
|
||
|
|
OutStreamer->emitCFIUndefined(Inst.getRegister());
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfDIE(const DIE &Die) const {
|
||
|
|
// Emit the code (index) for the abbreviation.
|
||
|
|
if (isVerbose())
|
||
|
|
OutStreamer->AddComment("Abbrev [" + Twine(Die.getAbbrevNumber()) + "] 0x" +
|
||
|
|
Twine::utohexstr(Die.getOffset()) + ":0x" +
|
||
|
|
Twine::utohexstr(Die.getSize()) + " " +
|
||
|
|
dwarf::TagString(Die.getTag()));
|
||
|
|
emitULEB128(Die.getAbbrevNumber());
|
||
|
|
|
||
|
|
// Emit the DIE attribute values.
|
||
|
|
for (const auto &V : Die.values()) {
|
||
|
|
dwarf::Attribute Attr = V.getAttribute();
|
||
|
|
assert(V.getForm() && "Too many attributes for DIE (check abbreviation)");
|
||
|
|
|
||
|
|
if (isVerbose()) {
|
||
|
|
OutStreamer->AddComment(dwarf::AttributeString(Attr));
|
||
|
|
if (Attr == dwarf::DW_AT_accessibility)
|
||
|
|
OutStreamer->AddComment(
|
||
|
|
dwarf::AccessibilityString(V.getDIEInteger().getValue()));
|
||
|
|
}
|
||
|
|
|
||
|
|
// Emit an attribute using the defined form.
|
||
|
|
V.emitValue(this);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Emit the DIE children if any.
|
||
|
|
if (Die.hasChildren()) {
|
||
|
|
for (auto &Child : Die.children())
|
||
|
|
emitDwarfDIE(Child);
|
||
|
|
|
||
|
|
OutStreamer->AddComment("End Of Children Mark");
|
||
|
|
emitInt8(0);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void AsmPrinter::emitDwarfAbbrev(const DIEAbbrev &Abbrev) const {
|
||
|
|
// Emit the abbreviations code (base 1 index.)
|
||
|
|
emitULEB128(Abbrev.getNumber(), "Abbreviation Code");
|
||
|
|
|
||
|
|
// Emit the abbreviations data.
|
||
|
|
Abbrev.Emit(this);
|
||
|
|
}
|