[llvm] [AMDGPU][gfx1250] Implement SIMemoryLegalizer (PR #154726)

[Christudasan Devadasan via llvm-commits]

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@@ -1656,6 +1656,11 @@ let OtherPredicates = [HasImageInsts] in {
   def S_WAIT_KMCNT_soft : SOPP_Pseudo <"s_soft_wait_kmcnt", (ins s16imm:$simm16), "$simm16">;
 }
 
+
+let SubtargetPredicate = HasWaitXcnt in {
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cdevadas wrote:

> If this is an instruction that doesn't exist on other targets, than it is?

We will eventually have them in the future revisions. Overall, IIUC, the subtarget name is better to use if you directly mention the generation name(s) in the predicate string. Any other feature name can go in the other predicates.

https://github.com/llvm/llvm-project/pull/154726