[PATH] Fix instruction size computation on amd64

Hi,

The attached small path fixes X86InstrInfo::getMemModRMByteSize to be consistent with the emit code in X86CodeEmitter::emitMemModRMByte on amd64.

Zoltan

llvm.diff (530 Bytes)

Thanks, applied!
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20090406/076154.html

-Chris