xref: /llvm-project/llvm/lib/MC/MCObjectWriter.cpp (revision 219d80bcb734bc4cbe3846fc49c5f21c31ba11be)
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() { FileNames.clear(); }
23 
24 bool MCObjectWriter::isSymbolRefDifferenceFullyResolved(
25     const MCAssembler &Asm, const MCSymbolRefExpr *A, const MCSymbolRefExpr *B,
26     bool InSet) const {
27   // Modified symbol references cannot be resolved.
28   if (A->getKind() != MCSymbolRefExpr::VK_None ||
29       B->getKind() != MCSymbolRefExpr::VK_None)
30     return false;
31 
32   const MCSymbol &SA = A->getSymbol();
33   const MCSymbol &SB = B->getSymbol();
34   assert(!SA.isUndefined() && !SB.isUndefined());
35   MCFragment *FB = SB.getFragment();
36   if (!FB || !SA.getFragment())
37     return false;
38 
39   return isSymbolRefDifferenceFullyResolvedImpl(Asm, SA, *FB, InSet, /*IsPCRel=*/false);
40 }
41 
42 bool MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
43     const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB,
44     bool InSet, bool IsPCRel) const {
45   const MCSection &SecA = SymA.getSection();
46   const MCSection &SecB = *FB.getParent();
47   // On ELF and COFF  A - B is absolute if A and B are in the same section.
48   return &SecA == &SecB;
49 }
50 
51 void MCObjectWriter::addFileName(MCAssembler &Asm, StringRef FileName) {
52   FileNames.emplace_back(std::string(FileName), Asm.Symbols.size());
53 }
54