[llvm] [VPlan] Add convertToUniformRecipe transform. (PR #139150)

[Florian Hahn via llvm-commits]

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@@ -7,86 +7,87 @@ define void @test(ptr %p, i40 %a) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
 ; CHECK:       vector.ph:
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i1 true, false
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fhahn wrote:

Yep, trivial folding that at the moment happens in IRBuilder on VPWidenRecipe, but not on replicate recipes which clone the original instruction. Will be fixed by pending VP constant folder

https://github.com/llvm/llvm-project/pull/139150