[llvm] [VPlan] Don't apply predication discount to non-originally-predicated blocks (PR #160449)

[Luke Lau via llvm-commits]

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@@ -49,6 +49,8 @@ define void @sink_replicate_region_1(i32 %x, ptr %ptr, ptr noalias %dst) optsize
 ; CHECK-NEXT: loop.0:
 ; CHECK-NEXT:   WIDEN-CAST ir<%conv> = sext vp<[[PRED1]]> to i32
 ; CHECK-NEXT:   EMIT vp<[[SPLICE:%.+]]> = first-order splice ir<%0>, ir<%conv>
+; CHECK-NEXT:   WIDEN ir<%rem> = srem vp<[[SPLICE]]>, ir<%x>
+; CHECK-NEXT:   WIDEN ir<%add> = add ir<%conv>, ir<%rem>
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lukel97 wrote:

Just noting here that we can't explicitly predicate this test because the srem that's being sunk is used in the FOR chain

https://github.com/llvm/llvm-project/pull/160449