When referring to a symbol in a dwarf section on ELF we should use
.long foo
instead of
.long foo - .debug_something
because ELF is unaware of the content of the sections and therefore needs
relocations. This has nothing to do with optimizing a -0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231751
91177308-0d34-0410-b5e6-
96231b3b80d8
raw_ostream &OS,
const MCExpr *Subsection) const = 0;
- /// isBaseAddressKnownZero - Return true if we know that this section will
- /// get a base address of zero. In cases where we know that this is true we
- /// can emit section offsets as direct references to avoid a subtraction
- /// from the base of the section, saving a relocation.
- virtual bool isBaseAddressKnownZero() const {
- return false;
- }
-
// UseCodeAlign - Return true if a .align directive should use
// "optimized nops" to fill instead of 0s.
virtual bool UseCodeAlign() const = 0;
bool UseCodeAlign() const override;
bool isVirtualSection() const override;
- /// isBaseAddressKnownZero - We know that non-allocatable sections (like
- /// debug info) have a base of zero.
- bool isBaseAddressKnownZero() const override {
- return (getFlags() & ELF::SHF_ALLOC) == 0;
- }
-
static bool classof(const MCSection *S) {
return S->getVariant() == SV_ELF;
}
assert((!Label->isInSection() || &Label->getSection() == &Section) &&
"Section offset using wrong section base for label");
- // If the section in question will end up with an address of 0 anyway, we can
- // just emit an absolute reference to save a relocation.
- if (Section.isBaseAddressKnownZero()) {
+ // If the format uses relocations with dwarf, refer to the symbol directly.
+ if (MAI->doesDwarfUseRelocationsAcrossSections()) {
OutStreamer.EmitSymbolValue(Label, 4);
return;
}
const MCExpr *Subsection) const override {}
/// Base address of PTX sections is zero.
- bool isBaseAddressKnownZero() const override { return true; }
bool UseCodeAlign() const override { return false; }
bool isVirtualSection() const override { return false; }
};