Fix pr24486.
This extends the work done in r233995 so that now getFragment (in addition to
getSection) also works for variable symbols.
With that the existing logic to decide if a-b can be computed works even if
a or b are variables. Given that, the expression evaluation can avoid expanding
variables as aggressively and that in turn lets the relocation code see the
original variable.
In order for this to work with the asm streamer, there is now a dummy fragment
per section. It is used to assign a section to a symbol when no other fragment
exists.
This patch is a joint work by Maxim Ostapenko andy myself.
llvm-svn: 249303
diff --git a/llvm/lib/MC/MCELFStreamer.cpp b/llvm/lib/MC/MCELFStreamer.cpp
index f0b3ec6..fc4f8a6 100644
--- a/llvm/lib/MC/MCELFStreamer.cpp
+++ b/llvm/lib/MC/MCELFStreamer.cpp
@@ -111,7 +111,7 @@
MCObjectStreamer::EmitLabel(Symbol);
const MCSectionELF &Section =
- static_cast<const MCSectionELF&>(Symbol->getSection());
+ static_cast<const MCSectionELF &>(*getCurrentSectionOnly());
if (Section.getFlags() & ELF::SHF_TLS)
Symbol->setType(ELF::STT_TLS);
}
@@ -311,11 +311,6 @@
Symbol->setType(ELF::STT_OBJECT);
if (Symbol->getBinding() == ELF::STB_LOCAL) {
- MCSection *Section = getAssembler().getContext().getELFSection(
- ".bss", ELF::SHT_NOBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
-
- AssignSection(Symbol, Section);
-
struct LocalCommon L = {Symbol, Size, ByteAlignment};
LocalCommons.push_back(L);
} else {
@@ -630,7 +625,8 @@
const MCSymbol &Symbol = *i->Symbol;
uint64_t Size = i->Size;
unsigned ByteAlignment = i->ByteAlignment;
- MCSection &Section = Symbol.getSection();
+ MCSection &Section = *getAssembler().getContext().getELFSection(
+ ".bss", ELF::SHT_NOBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
getAssembler().registerSection(Section);
new MCAlignFragment(ByteAlignment, 0, 1, ByteAlignment, &Section);