[llvm] [AMDGPU] Legalize 64bit elements for BUILD_VECTOR on gfx942 (PR #145052)

[Matt Arsenault via llvm-commits]

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@@ -413,9 +425,12 @@ SITargetLowering::SITargetLowering(const TargetMachine &TM,
   }
 
   for (MVT Vec64 : {MVT::v16i64, MVT::v16f64}) {
-    setOperationAction(ISD::BUILD_VECTOR, Vec64, Promote);
-    AddPromotedToType(ISD::BUILD_VECTOR, Vec64, MVT::v32i32);
-
+    if (STI.hasMovB64())
+      setOperationAction(ISD::BUILD_VECTOR, Vec64, Legal);
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arsenm wrote:

This might be the default already? 

https://github.com/llvm/llvm-project/pull/145052