[X86][MC] Support encoding/decoding for APX CCMP/CTEST (#83863)

APX assembly syntax recommendations:
  https://cdrdv2.intel.com/v1/dl/getContent/817241

NOTE:
The change in llvm/tools/llvm-exegesis/lib/X86/Target.cpp is for test
LLVM ::
tools/llvm-exegesis/X86/latency/latency-SETCCr-cond-codes-sweep.s

For `SETcc`, llvm-exegesis would randomly choose 1 other instruction to
test with `SETcc`, after selecting the instruction, llvm-exegesis would
check if the operand is initialized and valid, if not
`randomizeTargetMCOperand` would choose a value for invalid operand, it
misses support for condition code operand, which cause the flaky failure
after `CCMP` supported.

llvm-exegesis can choose `CCMP` without specifying ccmp feature b/c it
use `MCSubtarget` and only16/32/64 bit is considered.
llvm-exegesis doesn't choose other instructions b/c requirement in
`hasAliasingRegistersThrough`: the instruction should use GPR (defined
by `SETcc`) and define `EFLAGS` (used by `SETcc`).

0 files changed, 0 insertions, 0 deletions