[llvm] [AMDGPU][MC] Instructions not to be supported in GFX940 (PR #109225)

[Matt Arsenault via llvm-commits]

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@@ -1132,7 +1132,7 @@ let OtherPredicates = [HasGFX10_BEncoding] in {
   >;
 }
 
-let SubtargetPredicate = isGFX8GFX9 in {
+let SubtargetPredicate = isGFX8GFX9NotGFX940 in {
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arsenm wrote:

These clumsy subtarget checks should really be replaced with a subtarget feature 

https://github.com/llvm/llvm-project/pull/109225