[RuntimeDyld] Fix ppc64 stub relocations on little-endian

When RuntimeDyldELF creates stub functions, it needs to install
relocations that will resolve to the final address of the target
routine. Since those are 16-bit relocs, they need to be applied to the
least-significant halfword of the instruction.  On big-endian ppc64,
this means that addresses have to be adjusted by 2, which is what the
code currently does.

However, on a little-endian system, the address must *not* be adjusted;
the least-significant halfword is the first one.  This patch updates the
RuntimeDyldELF code to take the target byte order into account.

llvm-svn: 211384
This commit is contained in:
Ulrich Weigand 2014-06-20 18:17:56 +00:00
parent 4eff6cdd2e
commit 32626014a6
1 changed files with 11 additions and 5 deletions

View File

@ -1205,14 +1205,20 @@ relocation_iterator RuntimeDyldELF::processRelocationRef(
ELF::R_PPC64_ADDR64, Value.Addend);
// Generates the 64-bits address loads as exemplified in section
// 4.5.1 in PPC64 ELF ABI.
RelocationEntry REhst(SectionID, StubTargetAddr - Section.Address + 2,
// 4.5.1 in PPC64 ELF ABI. Note that the relocations need to
// apply to the low part of the instructions, so we have to update
// the offset according to the target endianness.
uint64_t StubRelocOffset = StubTargetAddr - Section.Address;
if (!IsTargetLittleEndian)
StubRelocOffset += 2;
RelocationEntry REhst(SectionID, StubRelocOffset + 0,
ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
RelocationEntry REhr(SectionID, StubTargetAddr - Section.Address + 6,
RelocationEntry REhr(SectionID, StubRelocOffset + 4,
ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
RelocationEntry REh(SectionID, StubTargetAddr - Section.Address + 14,
RelocationEntry REh(SectionID, StubRelocOffset + 12,
ELF::R_PPC64_ADDR16_HI, Value.Addend);
RelocationEntry REl(SectionID, StubTargetAddr - Section.Address + 18,
RelocationEntry REl(SectionID, StubRelocOffset + 16,
ELF::R_PPC64_ADDR16_LO, Value.Addend);
if (Value.SymbolName) {