MASM accepts ESP/RSP being specified second in a memory address
operand, by silently making it the base register despite not being
specified first.
Consequently, we also permit an xmm/ymm index to be specified first
(possibly alone), nevertheless putting it in as index register.
2012-07-24 Jan Beulich <jbeulich@suse.com>
* config/tc-i386-intel.c (i386_intel_simplify_register): Handle
xmm/ymm index register being specified first as well as esp/rsp
base register being specified last in a memory operand.