[BPF] Fix .BTF.ext reloc type assigment issue
Commit f1db33c5c1a9 ("[BPF] Disable relocation for .BTF.ext section")
assigned relocation type R_BPF_NONE if the fixup type
is FK_Data_4 and the symbol is temporary.
The reason is we use FK_Data_4 as a fixup type
for insn offsets in .BTF.ext section.
Just checking whether the symbol is temporary is not enough.
For example, .debug_info may reference some strings whose
fixup is FK_Data_4 with a temporary symbol as well.
To truely reflect the case for .BTF.ext section,
this patch further checks that the section associateed with the symbol
must be SHF_ALLOC and SHF_EXECINSTR, i.e., in the text section.
This fixed the above-mentioned problem.
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 350637
diff --git a/llvm/lib/Target/BPF/MCTargetDesc/BPFELFObjectWriter.cpp b/llvm/lib/Target/BPF/MCTargetDesc/BPFELFObjectWriter.cpp
index 13f6142..32e79d0 100644
--- a/llvm/lib/Target/BPF/MCTargetDesc/BPFELFObjectWriter.cpp
+++ b/llvm/lib/Target/BPF/MCTargetDesc/BPFELFObjectWriter.cpp
@@ -57,8 +57,16 @@
// already been fulfilled by applyFixup(). No
// further relocation is needed.
if (const MCSymbolRefExpr *A = Target.getSymA()) {
- if (A->getSymbol().isTemporary())
- return ELF::R_BPF_NONE;
+ if (A->getSymbol().isTemporary()) {
+ MCSection &Section = A->getSymbol().getSection();
+ const MCSectionELF *SectionELF = dyn_cast<MCSectionELF>(&Section);
+ assert(SectionELF && "Null section for reloc symbol");
+
+ // The reloc symbol should be in text section.
+ unsigned Flags = SectionELF->getFlags();
+ if ((Flags & ELF::SHF_ALLOC) && (Flags & ELF::SHF_EXECINSTR))
+ return ELF::R_BPF_NONE;
+ }
}
return ELF::R_BPF_64_32;
}