add extra decoding entries to get the "proper" opcode names for width or reg-reg variants?

_From [bruen...@google.com](https://code.google.com/u/109494838902877177630/) on November 01, 2013 10:56:41_

There are a number of opcodes whose mnemonic name changes based on bitwidth or
on whether reg-reg or not: see the sequence in instr.h from OP_cbw through
OP_vmovlhps. These are more substantially different than the condition code
variants: "jae" vs "jnb" doesn't matter much, while "pinsrd" vs "pinsrq" does
matter a litle as it tells you the size of the argment, which is hard to
determine with DR's default disassembly if it's a memory operand. We could add
extra entries that split on modrm or on rex.w or on the data size prefix in
order to have the right name, but it's not clear it's worthwhile.

_Original issue: http://code.google.com/p/dynamorio/issues/detail?id=1307_