1 //===- lib/MC/MCObjectWriter.cpp - MCObjectWriter implementation ----------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "llvm/MC/MCAssembler.h"
11 #include "llvm/MC/MCExpr.h"
12 #include "llvm/MC/MCObjectWriter.h"
13 #include "llvm/MC/MCSymbol.h"
14 
15 using namespace llvm;
16 
~MCObjectWriter()17 MCObjectWriter::~MCObjectWriter() {
18 }
19 
isSymbolRefDifferenceFullyResolved(const MCAssembler & Asm,const MCSymbolRefExpr * A,const MCSymbolRefExpr * B,bool InSet) const20 bool MCObjectWriter::isSymbolRefDifferenceFullyResolved(
21     const MCAssembler &Asm, const MCSymbolRefExpr *A, const MCSymbolRefExpr *B,
22     bool InSet) const {
23   // Modified symbol references cannot be resolved.
24   if (A->getKind() != MCSymbolRefExpr::VK_None ||
25       B->getKind() != MCSymbolRefExpr::VK_None)
26     return false;
27 
28   const MCSymbol &SA = A->getSymbol();
29   const MCSymbol &SB = B->getSymbol();
30   if (SA.isUndefined() || SB.isUndefined())
31     return false;
32 
33   if (!SA.getFragment() || !SB.getFragment())
34     return false;
35 
36   return isSymbolRefDifferenceFullyResolvedImpl(Asm, SA, SB, InSet);
37 }
38 
isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler & Asm,const MCSymbol & A,const MCSymbol & B,bool InSet) const39 bool MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
40     const MCAssembler &Asm, const MCSymbol &A, const MCSymbol &B,
41     bool InSet) const {
42   return isSymbolRefDifferenceFullyResolvedImpl(Asm, A, *B.getFragment(), InSet,
43                                                 false);
44 }
45 
isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler & Asm,const MCSymbol & SymA,const MCFragment & FB,bool InSet,bool IsPCRel) const46 bool MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
47     const MCAssembler &Asm, const MCSymbol &SymA, const MCFragment &FB,
48     bool InSet, bool IsPCRel) const {
49   const MCSection &SecA = SymA.getSection();
50   const MCSection &SecB = *FB.getParent();
51   // On ELF and COFF  A - B is absolute if A and B are in the same section.
52   return &SecA == &SecB;
53 }
54 
isWeak(const MCSymbol &) const55 bool MCObjectWriter::isWeak(const MCSymbol &) const { return false; }
56