Support for 64-bit PC-relative relocations for X86_64

ELF files generated for X86_64 targets may contain 64-bit PC-relative
relocations. For instance, an exception handler table entry contains the start
of exception-throwing frame relative to the start of exception handler. As these
two labels belong to different sections, their difference and so the relocation
is 64-bit.

An attempt to parse such file, i.e. in DWARFContext::create, results in "failed
to compute relocation" error.

This fix adds support for such relocations to RelocationResolver.cpp.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D67779

Patch by Oleg Pliss (Oleg.Pliss@azul.com)

llvm-svn: 372447

diff --git a/llvm/lib/Object/RelocationResolver.cpp b/llvm/lib/Object/RelocationResolver.cpp
index 90ae4fa..ca89f56 100644 (file)
--- a/llvm/lib/Object/RelocationResolver.cpp
+++ b/llvm/lib/Object/RelocationResolver.cpp
@@ -30,6 +30,7 @@ static bool supportsX86_64(uint64_t Type) {
   case ELF::R_X86_64_DTPOFF32:
   case ELF::R_X86_64_DTPOFF64:
   case ELF::R_X86_64_PC32:
+  case ELF::R_X86_64_PC64:
   case ELF::R_X86_64_32:
   case ELF::R_X86_64_32S:
     return true;
@@ -47,6 +48,7 @@ static uint64_t resolveX86_64(RelocationRef R, uint64_t S, uint64_t A) {
   case ELF::R_X86_64_DTPOFF64:
     return S + getELFAddend(R);
   case ELF::R_X86_64_PC32:
+  case ELF::R_X86_64_PC64:
     return S + getELFAddend(R) - R.getOffset();
   case ELF::R_X86_64_32:
   case ELF::R_X86_64_32S: