[llvm] [VPlan] Directly use masks on recipes in dropPoisonGen (PR #193978)

[Ramkumar Ramachandra via llvm-commits]

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@@ -27,16 +27,16 @@ define void @vector_reverse_i32(ptr noalias %A, ptr noalias %B) {
 ; RV64-NEXT:    [[AVL:%.*]] = phi i64 [ 1023, %[[VECTOR_PH]] ], [ [[AVL_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; RV64-NEXT:    [[TMP19:%.*]] = call i32 @llvm.experimental.get.vector.length.i64(i64 [[AVL]], i32 4, i1 true)
 ; RV64-NEXT:    [[OFFSET_IDX:%.*]] = sub i64 1023, [[INDEX]]
-; RV64-NEXT:    [[TMP7:%.*]] = add nsw i64 [[OFFSET_IDX]], -1
-; RV64-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i32, ptr [[B]], i64 [[TMP7]]
+; RV64-NEXT:    [[TMP1:%.*]] = add i64 [[OFFSET_IDX]], -1
+; RV64-NEXT:    [[TMP8:%.*]] = getelementptr i32, ptr [[B]], i64 [[TMP1]]
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artagnon wrote:

Ah, the problem was with reverse-masks, due to Mel's recent patch!

https://github.com/llvm/llvm-project/pull/193978