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

[Florian Hahn via llvm-commits]

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@@ -84,14 +84,14 @@ define i64 @select_decreasing_induction_icmp_non_const_start(ptr %a, ptr %b, i64
 ; CHECK-NEXT:    [[BROADCAST_SPLATINSERT2:%.*]] = insertelement <vscale x 4 x i64> poison, i64 [[TMP7]], i64 0
 ; CHECK-NEXT:    [[BROADCAST_SPLAT3:%.*]] = shufflevector <vscale x 4 x i64> [[BROADCAST_SPLATINSERT2]], <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer
 ; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = sub i64 [[N]], [[INDEX]]
-; CHECK-NEXT:    [[TMP38:%.*]] = add nsw i64 [[OFFSET_IDX]], -1
-; CHECK-NEXT:    [[TMP39:%.*]] = getelementptr inbounds i64, ptr [[A]], i64 [[TMP38]]
+; CHECK-NEXT:    [[TMP8:%.*]] = add i64 [[OFFSET_IDX]], -1
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fhahn wrote:

yes, likely the same root cause as discussed here I think https://github.com/llvm/llvm-project/pull/193978#discussion_r3143592816

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