[llvm] [X86][MC] Support Enc/Dec for EGPR for promoted SHA instruction (PR #75582)

[Phoebe Wang via llvm-commits]

================
@@ -0,0 +1,10 @@
+# RUN: llvm-mc --disassemble %s -triple=x86_64 | FileCheck %s --check-prefixes=ATT
----------------
phoebewang wrote:

Should be better to use file/cpuid instead of file/instruction to organize the test?

https://github.com/llvm/llvm-project/pull/75582