x86: eliminate redundant REX prefixes in front of x86_64 instruction. bug reported by Aurélien Wailly
x86: only eliminate REX prefixes if next byte is not a legacy prefix
Merge branch 'next' into rex
Merge branch 'next' into rex
x86: support some new instructions or new encodings of some new instructions: MOVSXD, FXCH, FCOM, FCOMP, FSTP, FSTPNCE, NOP
ppc: fix some compilation bugs when DIET mode is enable
x86: allow to mix REX & legacy prefix repeatedly in any order
x86: instruction length must be <= 15
x86: check instruction size <=15 as soon as possible