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

[Florian Hahn via llvm-commits]

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@@ -28,28 +28,45 @@ target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3
 ; CHECK-NEXT: vector.body:
 ; CHECK-NEXT:   EMIT vp<[[CAN_IV:%.+]]> = CANONICAL-INDUCTION
 ; CHECK-NEXT:   ir<%iv> = WIDEN-INDUCTION ir<0>, ir<1>, vp<[[VF]]>
+; CHECK-NEXT:   vp<[[STEPS:%.+]]> = SCALAR-STEPS vp<[[CAN_IV]]>, ir<1>, vp<[[VF]]>
 ; CHECK-NEXT:   EMIT vp<[[MASK:%.+]]> = icmp ule ir<%iv>, vp<[[BTC]]>
-; CHECK-NEXT: Successor(s): pred.store
-
-; CHECK:      <xVFxUF> pred.store: {
-; CHECK-NEXT:   pred.store.entry:
-; CHECK-NEXT:     BRANCH-ON-MASK vp<[[MASK]]>
-; CHECK-NEXT:   Successor(s): pred.store.if, pred.store.continue
-
-; CHECK:      pred.store.if:
-; CHECK-NEXT:     vp<[[STEPS:%.+]]> = SCALAR-STEPS vp<[[CAN_IV]]>, ir<1>
-; CHECK-NEXT:     REPLICATE ir<%gep.b> = getelementptr inbounds ir<@b>, ir<0>, vp<[[STEPS]]>
-; CHECK-NEXT:     REPLICATE ir<%lv.b> = load ir<%gep.b>
-; CHECK-NEXT:     REPLICATE ir<%add> = add ir<%lv.b>, ir<10>
-; CHECK-NEXT:     REPLICATE ir<%gep.a> = getelementptr inbounds ir<@a>, ir<0>, vp<[[STEPS]]
-; CHECK-NEXT:     REPLICATE ir<%mul> = mul ir<2>, ir<%add>
-; CHECK-NEXT:     REPLICATE store ir<%mul>, ir<%gep.a>
-; CHECK-NEXT:   Successor(s): pred.store.continue
-
-; CHECK:      pred.store.continue:
-; CHECK-NEXT:   No successors
-; CHECK-NEXT: }
-
+; CHECK-NEXT: Successor(s): pred.load
+; CHECK-EMPTY:
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fhahn wrote:

I think this is no not testing what it used to (replicate regions aren't merged any more), would be good to adjust the test so this merging still takes place

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