[llvm] [VPlan] Impl VPlan-based pattern match for ExtendedRed and MulAccRed (PR #113903)

[Florian Hahn via llvm-commits]

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@@ -1200,6 +1200,148 @@ exit:
   ret i16 %for.1
 }
 
+define i64 @print_extended_reduction(ptr nocapture readonly %x, ptr nocapture readonly %y, i32 %n) {
+; CHECK-LABEL: 'print_extended_reduction'
+; CHECK:      VPlan 'Initial VPlan for VF={4},UF>=1' {
+; CHECK-NEXT: Live-in vp<%0> = VF * UF
+; CHECK-NEXT: Live-in vp<%1> = vector-trip-count
+; CHECK-NEXT: Live-in ir<%n> = original trip-count
+; CHECK-EMPTY:
+; CHECK:      vector.ph:
+; CHECK-NEXT: Successor(s): vector loop
+; CHECK-EMPTY:
+; CHECK-NEXT: <x1> vector loop: {
+; CHECK-NEXT:   vector.body:
+; CHECK-NEXT:     EMIT vp<%2> = CANONICAL-INDUCTION ir<0>, vp<%index.next>
+; CHECK-NEXT:     WIDEN-REDUCTION-PHI ir<%rdx> = phi ir<0>, vp<%5>
+; CHECK-NEXT:     vp<%3> = SCALAR-STEPS vp<%2>, ir<1>
+; CHECK-NEXT:     CLONE ir<%arrayidx> = getelementptr inbounds ir<%x>, vp<%3>
+; CHECK-NEXT:     vp<%4> = vector-pointer ir<%arrayidx>
+; CHECK-NEXT:     WIDEN ir<%load0> = load vp<%4>
+; CHECK-NEXT:     EXTENDED-REDUCE vp<%5> = ir<%rdx> + reduce.add (ir<%load0> extended to i64)
+; CHECK-NEXT:     EMIT vp<%index.next> = add nuw vp<%2>, vp<%0>
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fhahn wrote:

Could you update the tests not use hard-coded VPValue numbers? Same for the other ned tests

https://github.com/llvm/llvm-project/pull/113903