[llvm] [X86] Use RORX over SHR imm (PR #77964)

[Bryce Wilson via llvm-commits]

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@@ -879,6 +879,26 @@ let Predicates = [HasBMI2, HasEGPR, In64BitMode] in {
   defm SHLX64 : bmi_shift<"shlx{q}", GR64, i64mem, "_EVEX">, T8, PD, REX_W, EVEX;
 }
 
+
+def immle16_8 : ImmLeaf<i8, [{
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Bryce-MW wrote:

Good idea. I was trying to make something that took two parameters (e.g. `immle<16, 8>`) but I couldn't quite figure that out

https://github.com/llvm/llvm-project/pull/77964