[llvm] [VPlan] Add VPlan-dump-based test for predication (PR #180794)

[Andrei Elovikov via llvm-commits]

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@@ -0,0 +1,389 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -disable-output < %s -p loop-vectorize -vplan-print-after=introduceMasksAndLinearize -vplan-print-vector-region-scope 2>&1 | FileCheck %s
+
+define void @diamond_phi(ptr %a) {
+; CHECK-LABEL: 'diamond_phi'
+; CHECK-NEXT:  <x1> vector loop: {
+; CHECK-NEXT:    vector.body:
+; CHECK-NEXT:      EMIT vp<[[VP3:%[0-9]+]]> = CANONICAL-INDUCTION ir<0>, vp<%index.next>
+; CHECK-NEXT:      ir<%iv> = WIDEN-INDUCTION nuw nsw ir<0>, ir<1>, vp<[[VP0:%[0-9]+]]>
+; CHECK-NEXT:      EMIT ir<%gep> = getelementptr ir<%a>, ir<%iv>
+; CHECK-NEXT:      EMIT ir<%c0> = icmp sle ir<%iv>, ir<0>
+; CHECK-NEXT:    Successor(s): bb2
+; CHECK-EMPTY:
+; CHECK-NEXT:    bb2:
+; CHECK-NEXT:      EMIT vp<[[VP4:%[0-9]+]]> = not ir<%c0>
+; CHECK-NEXT:      EMIT ir<%add2> = add ir<%iv>, ir<2>, vp<[[VP4]]>
+; CHECK-NEXT:    Successor(s): bb1
+; CHECK-EMPTY:
+; CHECK-NEXT:    bb1:
+; CHECK-NEXT:      EMIT ir<%add1> = add ir<%iv>, ir<1>, ir<%c0>
+; CHECK-NEXT:    Successor(s): bb4
+; CHECK-EMPTY:
+; CHECK-NEXT:    bb4:
+; CHECK-NEXT:      EMIT vp<[[VP5:%[0-9]+]]> = or vp<[[VP4]]>, ir<%c0>
+; CHECK-NEXT:      BLEND ir<%phi4> = ir<%add2>/vp<[[VP4]]> ir<%add1>/ir<%c0>
+; CHECK-NEXT:      EMIT store ir<%phi4>, ir<%gep>, vp<[[VP5]]>
+; CHECK-NEXT:      EMIT ir<%iv.next> = add nuw nsw ir<%iv>, ir<1>, vp<[[VP5]]>
+; CHECK-NEXT:      EMIT ir<%ec> = icmp eq ir<%iv.next>, ir<128>, vp<[[VP5]]>
+; CHECK-NEXT:      EMIT vp<%index.next> = add nuw vp<[[VP3]]>, vp<[[VP1:%[0-9]+]]>
+; CHECK-NEXT:      EMIT branch-on-count vp<%index.next>, vp<[[VP2:%[0-9]+]]>
+; CHECK-NEXT:    No successors
+; CHECK-NEXT:  }
+; CHECK-NEXT:  Successor(s): middle.block
+;
+entry:
+  br label %bb0
+
+bb0:
----------------
eas wrote:

I've chosen the current scheme on purpose to make it more uniform for all the blocks and to have the same `bbN/cN/addN/phiN` pattern. The loop-related part is unrelated for the purposes of this test.

https://github.com/llvm/llvm-project/pull/180794