diff options
| -rw-r--r-- | lib/Target/X86/X86AsmBackend.cpp | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/lib/Target/X86/X86AsmBackend.cpp b/lib/Target/X86/X86AsmBackend.cpp index ba9c1d0588..b72601ae58 100644 --- a/lib/Target/X86/X86AsmBackend.cpp +++ b/lib/Target/X86/X86AsmBackend.cpp @@ -12,6 +12,7 @@ #include "X86FixupKinds.h" #include "llvm/ADT/Twine.h" #include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCExpr.h" #include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSectionELF.h" #include "llvm/MC/MCSectionMachO.h" @@ -88,9 +89,20 @@ static unsigned getRelaxedOpcode(unsigned Op) { bool X86AsmBackend::MayNeedRelaxation(const MCInst &Inst, const SmallVectorImpl<MCAsmFixup> &Fixups) const { - // Check for a 1byte pcrel fixup, and enforce that we would know how to relax - // this instruction. for (unsigned i = 0, e = Fixups.size(); i != e; ++i) { + // We don't support relaxing anything else currently. Make sure we error out + // if we see a non-constant 1 or 2 byte fixup. + // + // FIXME: We should need to check this here, this is better checked in the + // object writer which should be verifying that any final relocations match + // the expected fixup. However, that code is more complicated and hasn't + // been written yet. See the FIXMEs in MachObjectWriter.cpp. + if ((Fixups[i].Kind == FK_Data_1 || Fixups[i].Kind == FK_Data_2) && + !isa<MCConstantExpr>(Fixups[i].Value)) + report_fatal_error("unexpected small fixup with a non-constant operand!"); + + // Check for a 1byte pcrel fixup, and enforce that we would know how to + // relax this instruction. if (unsigned(Fixups[i].Kind) == X86::reloc_pcrel_1byte) { assert(getRelaxedOpcode(Inst.getOpcode()) != Inst.getOpcode()); return true; |