[llvm] [AMDGPU][True16][CodeGen] add a d16 predicate for true16 mode (PR #156574)

[Joe Nash via llvm-commits]

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@@ -16,15 +16,19 @@ def FalsePredicate : Predicate<"false">;
 class True16PredicateClass<string cond> : Predicate<cond>;
 def NoTrue16Predicate : True16PredicateClass<"">;
 
+class TrueD16PredicateClass<string cond> : Predicate<cond>;
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Sisyph wrote:

Why do you want to put the UseRealTrueD16Insts into the True16Predicate class? It seems to me it could just be a normal predicate. Then the patterns could be guarded with OtherPredicates = [*, UseRealTrueD16Insts] and leave the True16Predicate unchanged.

https://github.com/llvm/llvm-project/pull/156574