diff options
| -rw-r--r-- | lib/MC/MachObjectWriter.cpp | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp index e12daa708b..17615eef69 100644 --- a/lib/MC/MachObjectWriter.cpp +++ b/lib/MC/MachObjectWriter.cpp @@ -1126,6 +1126,31 @@ public: bool IsSymbolRefDifferenceFullyResolved(const MCAssembler &Asm, const MCSymbolRefExpr *A, const MCSymbolRefExpr *B) const { + // The effective address is + // addr(atom(A)) + offset(A) + // - addr(atom(B)) - offset(B) + // and the offsets are not relocatable, so the fixup is fully resolved when + // addr(atom(A)) - addr(atom(B)) == 0. + const MCSymbolData *A_Base = 0, *B_Base = 0; + + // Modified symbol references cannot be resolved. + if (A->getKind() != MCSymbolRefExpr::VK_None || + B->getKind() != MCSymbolRefExpr::VK_None) + return false; + + A_Base = Asm.getAtom(&Asm.getSymbolData(A->getSymbol())); + if (!A_Base) + return false; + + B_Base = Asm.getAtom(&Asm.getSymbolData(B->getSymbol())); + if (!B_Base) + return false; + + // If the atoms are the same, they are guaranteed to have the same address. + if (A_Base == B_Base) + return true; + + // Otherwise, we can't prove this is fully resolved. return false; } |