static bool canGoAfterDWARF(const MCSectionMachO &MSec) {
// These sections are created by the assembler itself after the end of
// the .s file.
StringRef SegName = MSec.getSegmentName();
StringRef SecName = MSec.getSectionName();
if (SegName == "__LD" && SecName == "__compact_unwind")
return true;
if (SegName == "__IMPORT") {
if (SecName == "__jump_table")
return true;
if (SecName == "__pointers")
return true;
}
if (SegName == "__TEXT" && SecName == "__eh_frame")
return true;
if (SegName == "__DATA" && SecName == "__nl_symbol_ptr")
return true;
return false;
}
static bool canUseLocalRelocation(const MCSectionMachO &Section,
const MCSymbol &Symbol, unsigned Log2Size) {
// Debug info sections can use local relocations.
if (Section.hasAttribute(MachO::S_ATTR_DEBUG))
return true;
// Otherwise, only pointer sized relocations are supported.
if (Log2Size != 3)
return false;
// But only if they don't point to a few forbidden sections.
if (!Symbol.isInSection())
return true;
const MCSectionMachO &RefSec = cast<MCSectionMachO>(Symbol.getSection());
if (RefSec.getType() == MachO::S_CSTRING_LITERALS)
return false;
if (RefSec.getSegmentName() == "__DATA" &&
RefSec.getSectionName() == "__cfstring")
return false;
if (RefSec.getSegmentName() == "__DATA" &&
RefSec.getSectionName() == "__objc_classrefs")
return false;
return true;
}
static bool canUseLocalRelocation(const MCSectionMachO &Section,
const MCSymbol &Symbol, unsigned Log2Size) {
// Debug info sections can use local relocations.
if (Section.hasAttribute(MachO::S_ATTR_DEBUG))
return true;
// Otherwise, only pointer sized relocations are supported.
if (Log2Size != 3)
return false;
// But only if they don't point to a few forbidden sections.
if (!Symbol.isInSection())
return true;
const MCSectionMachO &RefSec = cast<MCSectionMachO>(Symbol.getSection());
if (RefSec.getType() == MachO::S_CSTRING_LITERALS)
return false;
if (RefSec.getSegmentName() == "__DATA" &&
RefSec.getSectionName() == "__objc_classrefs")
return false;
// FIXME: ld64 currently handles internal pointer-sized relocations
// incorrectly (applying the addend twice). We should be able to return true
// unconditionally by this point when that's fixed.
return false;
}
MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal(
const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
const TargetMachine &TM) const {
// Parse the section specifier and create it if valid.
StringRef Segment, Section;
unsigned TAA = 0, StubSize = 0;
bool TAAParsed;
checkMachOComdat(GV);
std::string ErrorCode =
MCSectionMachO::ParseSectionSpecifier(GV->getSection(), Segment, Section,
TAA, TAAParsed, StubSize);
if (!ErrorCode.empty()) {
// If invalid, report the error with report_fatal_error.
report_fatal_error("Global variable '" + GV->getName() +
"' has an invalid section specifier '" +
GV->getSection() + "': " + ErrorCode + ".");
}
// Get the section.
MCSectionMachO *S =
getContext().getMachOSection(Segment, Section, TAA, StubSize, Kind);
// If TAA wasn't set by ParseSectionSpecifier() above,
// use the value returned by getMachOSection() as a default.
if (!TAAParsed)
TAA = S->getTypeAndAttributes();
// Okay, now that we got the section, verify that the TAA & StubSize agree.
// If the user declared multiple globals with different section flags, we need
// to reject it here.
if (S->getTypeAndAttributes() != TAA || S->getStubSize() != StubSize) {
// If invalid, report the error with report_fatal_error.
report_fatal_error("Global variable '" + GV->getName() +
"' section type or attributes does not match previous"
" section specifier");
}
return S;
}