bool MachObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
const MCAssembler &Asm, const MCSymbol &A, const MCSymbol &B,
bool InSet) const {
// FIXME: We don't handle things like
// foo = .
// creating atoms.
if (A.isVariable() || B.isVariable())
return false;
return MCObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(Asm, A, B,
InSet);
}
uint64_t MachObjectWriter::getSymbolAddress(const MCSymbol &S,
const MCAsmLayout &Layout) const {
// If this is a variable, then recursively evaluate now.
if (S.isVariable()) {
if (const MCConstantExpr *C =
dyn_cast<const MCConstantExpr>(S.getVariableValue()))
return C->getValue();
MCValue Target;
if (!S.getVariableValue()->evaluateAsRelocatable(Target, &Layout, nullptr))
report_fatal_error("unable to evaluate offset for variable '" +
S.getName() + "'");
// Verify that any used symbols are defined.
if (Target.getSymA() && Target.getSymA()->getSymbol().isUndefined())
report_fatal_error("unable to evaluate offset to undefined symbol '" +
Target.getSymA()->getSymbol().getName() + "'");
if (Target.getSymB() && Target.getSymB()->getSymbol().isUndefined())
report_fatal_error("unable to evaluate offset to undefined symbol '" +
Target.getSymB()->getSymbol().getName() + "'");
uint64_t Address = Target.getConstant();
if (Target.getSymA())
Address += getSymbolAddress(Target.getSymA()->getSymbol(), Layout);
if (Target.getSymB())
Address += getSymbolAddress(Target.getSymB()->getSymbol(), Layout);
return Address;
}
return getSectionAddress(S.getFragment()->getParent()) +
Layout.getSymbolOffset(S);
}
static bool getSymbolOffsetImpl(const MCAsmLayout &Layout, const MCSymbol &S,
bool ReportError, uint64_t &Val) {
if (!S.isVariable())
return getLabelOffset(Layout, S, ReportError, Val);
// If SD is a variable, evaluate it.
MCValue Target;
if (!S.getVariableValue()->evaluateAsValue(Target, Layout))
report_fatal_error("unable to evaluate offset for variable '" +
S.getName() + "'");
uint64_t Offset = Target.getConstant();
const MCSymbolRefExpr *A = Target.getSymA();
if (A) {
uint64_t ValA;
if (!getLabelOffset(Layout, A->getSymbol(), ReportError, ValA))
return false;
Offset += ValA;
}
const MCSymbolRefExpr *B = Target.getSymB();
if (B) {
uint64_t ValB;
if (!getLabelOffset(Layout, B->getSymbol(), ReportError, ValB))
return false;
Offset -= ValB;
}
Val = Offset;
return true;
}