[llvm] [VPlan] Unroll VPReplicateRecipe by VF. (PR #142433)

[Florian Hahn via llvm-commits]

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@@ -229,6 +229,10 @@ define void @redundant_branch_and_blends_without_mask(ptr %A) {
 ; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP1]]
 ; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP2]]
 ; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP3]]
+; CHECK-NEXT:    [[TMP35:%.*]] = insertelement <4 x ptr> poison, ptr [[TMP5]], i32 0
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fhahn wrote:

Yes, this is a case we won't be able to handle until we also unroll replicate regions by VF. There is a use in the VPReplicateRecipe in a replicate region, which prevents us from removing the BuildVector, even though during codegen we don't use it.

https://github.com/llvm/llvm-project/pull/142433