llvm/lib/MC/MCObjectWriter.cpp

   1 //===- lib/MC/MCObjectWriter.cpp - MCObjectWriter implementation ----------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/MC/MCObjectWriter.h"
  10 #include "llvm/MC/MCAssembler.h"
  11 #include "llvm/MC/MCExpr.h"
  12 #include "llvm/MC/MCFragment.h"
  13 #include "llvm/MC/MCSymbol.h"
  14 namespace llvm {
  15 class MCSection;
  16 }
  17
  18 using namespace llvm;
  19
  20 MCObjectWriter::~MCObjectWriter() = default;
  21
  22 void MCObjectWriter::reset() {
  23   FileNames.clear();
  24   AddrsigSyms.clear();
  25   EmitAddrsigSection = false;
  26   SubsectionsViaSymbols = false;
  27   CGProfile.clear();
  28 }
  29
  30 bool MCObjectWriter::isSymbolRefDifferenceFullyResolved(
  31     const MCAssembler &Asm, const MCSymbolRefExpr *A, const MCSymbolRefExpr *B,
  32     bool InSet) const {
  33   // Modified symbol references cannot be resolved.
  34   if (A->getKind() != MCSymbolRefExpr::VK_None ||
  35       B->getKind() != MCSymbolRefExpr::VK_None)
  36     return false;
  37
  38   const MCSymbol &SA = A->getSymbol();
  39   const MCSymbol &SB = B->getSymbol();
  40   assert(!SA.isUndefined() && !SB.isUndefined());
  41   MCFragment *FB = SB.getFragment();
  42   if (!FB || !SA.getFragment())
  43     return false;
  44
  45   return isSymbolRefDifferenceFullyResolvedImpl(Asm, SA, *FB, InSet, /*IsPCRel=*/false);
  46 }
  47
  48 bool MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
  49     const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB,
  50     bool InSet, bool IsPCRel) const {
  51   const MCSection &SecA = SymA.getSection();
  52   const MCSection &SecB = *FB.getParent();
  53   // On ELF and COFF  A - B is absolute if A and B are in the same section.
  54   return &SecA == &SecB;
  55 }
  56
  57 void MCObjectWriter::addFileName(MCAssembler &Asm, StringRef FileName) {
  58   FileNames.emplace_back(std::string(FileName), Asm.Symbols.size());
  59 }