Coverage Report

Created: 2017-10-03 07:32

/Users/buildslave/jenkins/sharedspace/clang-stage2-coverage-R@2/llvm/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp
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//===-- AsmPrinterDwarf.cpp - AsmPrinter Dwarf Support --------------------===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the Dwarf emissions parts of AsmPrinter.
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//
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//===----------------------------------------------------------------------===//
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#include "ByteStreamer.h"
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#include "DwarfDebug.h"
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#include "DwarfExpression.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/BinaryFormat/Dwarf.h"
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#include "llvm/CodeGen/AsmPrinter.h"
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#include "llvm/CodeGen/DIE.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineModuleInfo.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/MC/MCAsmInfo.h"
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#include "llvm/MC/MCRegisterInfo.h"
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#include "llvm/MC/MCSection.h"
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#include "llvm/MC/MCStreamer.h"
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#include "llvm/MC/MCSymbol.h"
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#include "llvm/MC/MachineLocation.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Target/TargetLoweringObjectFile.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetSubtargetInfo.h"
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using namespace llvm;
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#define DEBUG_TYPE "asm-printer"
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//===----------------------------------------------------------------------===//
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// Dwarf Emission Helper Routines
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//===----------------------------------------------------------------------===//
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/// EmitSLEB128 - emit the specified signed leb128 value.
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4.52k
void AsmPrinter::EmitSLEB128(int64_t Value, const char *Desc) const {
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4.52k
  if (
isVerbose() && 4.52k
Desc507
)
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0
    OutStreamer->AddComment(Desc);
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4.52k
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4.52k
  OutStreamer->EmitSLEB128IntValue(Value);
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4.52k
}
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/// EmitULEB128 - emit the specified unsigned leb128 value.
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void AsmPrinter::EmitPaddedULEB128(uint64_t Value, unsigned PadTo,
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5.89k
                                   const char *Desc) const {
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5.89k
  if (
isVerbose() && 5.89k
Desc475
)
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475
    OutStreamer->AddComment(Desc);
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5.89k
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5.89k
  OutStreamer->EmitPaddedULEB128IntValue(Value, PadTo);
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5.89k
}
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226k
void AsmPrinter::EmitULEB128(uint64_t Value, const char *Desc) const {
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226k
  if (
isVerbose() && 226k
Desc25.4k
)
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22.0k
    OutStreamer->AddComment(Desc);
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226k
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226k
  OutStreamer->EmitULEB128IntValue(Value);
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226k
}
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729
static const char *DecodeDWARFEncoding(unsigned Encoding) {
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729
  switch (Encoding) {
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94
  case dwarf::DW_EH_PE_absptr:
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94
    return "absptr";
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254
  case dwarf::DW_EH_PE_omit:
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254
    return "omit";
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0
  case dwarf::DW_EH_PE_pcrel:
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0
    return "pcrel";
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289
  case dwarf::DW_EH_PE_udata4:
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289
    return "udata4";
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0
  case dwarf::DW_EH_PE_udata8:
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0
    return "udata8";
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0
  case dwarf::DW_EH_PE_sdata4:
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0
    return "sdata4";
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0
  case dwarf::DW_EH_PE_sdata8:
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0
    return "sdata8";
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0
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4:
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0
    return "pcrel udata4";
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0
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4:
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0
    return "pcrel sdata4";
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0
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8:
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0
    return "pcrel udata8";
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0
  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8:
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0
    return "pcrel sdata8";
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0
  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4
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0
      :
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0
    return "indirect pcrel udata4";
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  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
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      :
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    return "indirect pcrel sdata4";
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  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8
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      :
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    return "indirect pcrel udata8";
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  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8
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2
      :
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2
    return "indirect pcrel sdata8";
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0
  }
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0
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0
  return "<unknown encoding>";
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0
}
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/// EmitEncodingByte - Emit a .byte 42 directive that corresponds to an
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/// encoding.  If verbose assembly output is enabled, we output comments
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/// describing the encoding.  Desc is an optional string saying what the
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/// encoding is specifying (e.g. "LSDA").
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8.85k
void AsmPrinter::EmitEncodingByte(unsigned Val, const char *Desc) const {
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8.85k
  if (
isVerbose()8.85k
) {
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729
    if (Desc)
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729
      OutStreamer->AddComment(Twine(Desc) + " Encoding = " +
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729
                              Twine(DecodeDWARFEncoding(Val)));
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729
    else
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0
      OutStreamer->AddComment(Twine("Encoding = ") + DecodeDWARFEncoding(Val));
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729
  }
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8.85k
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8.85k
  OutStreamer->EmitIntValue(Val, 1);
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}
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/// GetSizeOfEncodedValue - Return the size of the encoding in bytes.
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4.83k
unsigned AsmPrinter::GetSizeOfEncodedValue(unsigned Encoding) const {
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4.83k
  if (Encoding == dwarf::DW_EH_PE_omit)
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0
    return 0;
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4.83k
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4.83k
  switch (Encoding & 0x07) {
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0
  default:
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0
    llvm_unreachable("Invalid encoded value.");
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  case dwarf::DW_EH_PE_absptr:
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    return MF->getDataLayout().getPointerSize();
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0
  case dwarf::DW_EH_PE_udata2:
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0
    return 2;
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4.65k
  case dwarf::DW_EH_PE_udata4:
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4.65k
    return 4;
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11
  case dwarf::DW_EH_PE_udata8:
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    return 8;
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0
  }
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0
}
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void AsmPrinter::EmitTTypeReference(const GlobalValue *GV,
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1.89k
                                    unsigned Encoding) const {
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1.89k
  if (
GV1.89k
) {
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    const TargetLoweringObjectFile &TLOF = getObjFileLowering();
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    const MCExpr *Exp =
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        TLOF.getTTypeGlobalReference(GV, Encoding, TM, MMI, *OutStreamer);
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    OutStreamer->EmitValue(Exp, GetSizeOfEncodedValue(Encoding));
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  } else
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1.58k
    OutStreamer->EmitIntValue(0, GetSizeOfEncodedValue(Encoding));
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1.89k
}
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void AsmPrinter::emitDwarfSymbolReference(const MCSymbol *Label,
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2.15k
                                          bool ForceOffset) const {
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2.15k
  if (
!ForceOffset2.15k
) {
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2.14k
    // On COFF targets, we have to emit the special .secrel32 directive.
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2.14k
    if (
MAI->needsDwarfSectionOffsetDirective()2.14k
) {
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120
      OutStreamer->EmitCOFFSecRel32(Label, /*Offset=*/0);
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      return;
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120
    }
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2.02k
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2.02k
    // If the format uses relocations with dwarf, refer to the symbol directly.
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2.02k
    
if (2.02k
MAI->doesDwarfUseRelocationsAcrossSections()2.02k
) {
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963
      OutStreamer->EmitSymbolValue(Label, 4);
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963
      return;
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963
    }
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1.06k
  }
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1.06k
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1.06k
  // Otherwise, emit it as a label difference from the start of the section.
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1.06k
  EmitLabelDifference(Label, Label->getSection().getBeginSymbol(), 4);
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1.06k
}
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17.1k
void AsmPrinter::emitDwarfStringOffset(DwarfStringPoolEntryRef S) const {
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17.1k
  if (
MAI->doesDwarfUseRelocationsAcrossSections()17.1k
) {
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39
    emitDwarfSymbolReference(S.getSymbol());
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39
    return;
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  }
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17.1k
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17.1k
  // Just emit the offset directly; no need for symbol math.
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17.1k
  EmitInt32(S.getOffset());
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17.1k
}
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//===----------------------------------------------------------------------===//
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// Dwarf Lowering Routines
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//===----------------------------------------------------------------------===//
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330k
void AsmPrinter::emitCFIInstruction(const MCCFIInstruction &Inst) const {
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330k
  switch (Inst.getOperation()) {
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0
  default:
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0
    llvm_unreachable("Unexpected instruction");
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18.3k
  case MCCFIInstruction::OpDefCfaOffset:
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18.3k
    OutStreamer->EmitCFIDefCfaOffset(Inst.getOffset());
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18.3k
    break;
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1.20k
  case MCCFIInstruction::OpAdjustCfaOffset:
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1.20k
    OutStreamer->EmitCFIAdjustCfaOffset(Inst.getOffset());
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1.20k
    break;
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35.6k
  case MCCFIInstruction::OpDefCfa:
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35.6k
    OutStreamer->EmitCFIDefCfa(Inst.getRegister(), Inst.getOffset());
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35.6k
    break;
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7.55k
  case MCCFIInstruction::OpDefCfaRegister:
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7.55k
    OutStreamer->EmitCFIDefCfaRegister(Inst.getRegister());
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7.55k
    break;
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266k
  case MCCFIInstruction::OpOffset:
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266k
    OutStreamer->EmitCFIOffset(Inst.getRegister(), Inst.getOffset());
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266k
    break;
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  case MCCFIInstruction::OpRegister:
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380
    OutStreamer->EmitCFIRegister(Inst.getRegister(), Inst.getRegister2());
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380
    break;
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380
  case MCCFIInstruction::OpWindowSave:
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380
    OutStreamer->EmitCFIWindowSave();
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380
    break;
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4
  case MCCFIInstruction::OpSameValue:
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4
    OutStreamer->EmitCFISameValue(Inst.getRegister());
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4
    break;
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18
  case MCCFIInstruction::OpGnuArgsSize:
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18
    OutStreamer->EmitCFIGnuArgsSize(Inst.getOffset());
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18
    break;
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0
  case MCCFIInstruction::OpEscape:
220
0
    OutStreamer->EmitCFIEscape(Inst.getValues());
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0
    break;
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330k
  }
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330k
}
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62.5k
void AsmPrinter::emitDwarfDIE(const DIE &Die) const {
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62.5k
  // Emit the code (index) for the abbreviation.
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62.5k
  if (isVerbose())
228
2.15k
    OutStreamer->AddComment("Abbrev [" + Twine(Die.getAbbrevNumber()) + "] 0x" +
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2.15k
                            Twine::utohexstr(Die.getOffset()) + ":0x" +
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2.15k
                            Twine::utohexstr(Die.getSize()) + " " +
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2.15k
                            dwarf::TagString(Die.getTag()));
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62.5k
  EmitULEB128(Die.getAbbrevNumber());
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62.5k
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62.5k
  // Emit the DIE attribute values.
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239k
  for (const auto &V : Die.values()) {
236
239k
    dwarf::Attribute Attr = V.getAttribute();
237
239k
    assert(V.getForm() && "Too many attributes for DIE (check abbreviation)");
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239k
239
239k
    if (
isVerbose()239k
) {
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9.87k
      OutStreamer->AddComment(dwarf::AttributeString(Attr));
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9.87k
      if (Attr == dwarf::DW_AT_accessibility)
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22
        OutStreamer->AddComment(
243
22
            dwarf::AccessibilityString(V.getDIEInteger().getValue()));
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9.87k
    }
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239k
246
239k
    // Emit an attribute using the defined form.
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239k
    V.EmitValue(this);
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239k
  }
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62.5k
250
62.5k
  // Emit the DIE children if any.
251
62.5k
  if (
Die.hasChildren()62.5k
) {
252
22.7k
    for (auto &Child : Die.children())
253
61.1k
      emitDwarfDIE(Child);
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22.7k
255
22.7k
    OutStreamer->AddComment("End Of Children Mark");
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22.7k
    EmitInt8(0);
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22.7k
  }
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62.5k
}
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260
10.0k
void AsmPrinter::emitDwarfAbbrev(const DIEAbbrev &Abbrev) const {
261
10.0k
  // Emit the abbreviations code (base 1 index.)
262
10.0k
  EmitULEB128(Abbrev.getNumber(), "Abbreviation Code");
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10.0k
264
10.0k
  // Emit the abbreviations data.
265
10.0k
  Abbrev.Emit(this);
266
10.0k
}