* Add a quick test helper macro to test_x86.c
* Add regression tests for bswap and rex prefixes
* Properly ignore REX prefixes when appropriate
* Fix bswap ax emulator detection
target/i386: fix operand order for PDEP and PEXT
For PDEP and PEXT, the mask is provided in the memory (mod+r/m)
operand, and therefore is loaded in s->T0 by gen_ldst_modrm.
The source is provided in the second source operand (VEX.vvvv)
and therefore is loaded in s->T1. Fix the order in which
they are passed to the helpers.
target/i386: Verify memory operand for lcall and ljmp
These two opcodes only allow a memory operand.
Lacking the check for a register operand, we used the A0 temp
without initialization, which led to a tcg abort.
