[llvm] [VPlan] Add hidden `-vplan-print-after-all` option (PR #175839)

[Andrei Elovikov via llvm-commits]

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@@ -0,0 +1,76 @@
+; REQUIRES: asserts
+
+; Verify that `-vplan-print-after-all` option works.
+
+; RUN: opt -passes=loop-vectorize -disable-output -vplan-print-after-all -force-vector-width=4 < %s 2>&1 | FileCheck %s --implicit-check-not "VPlan after"
+
+; CHECK: VPlan after printAfterInitialConstruction
+; CHECK: VPlan after VPlanTransforms::clearReductionWrapFlags
+; CHECK: VPlan after VPlanTransforms::handleMultiUseReductions
+; CHECK: VPlan after VPlanTransforms::handleMaxMinNumReductions
+; CHECK: VPlan after VPlanTransforms::handleFindLastReductions
+; CHECK: VPlan after VPlanTransforms::convertToAbstractRecipes
+; CHECK: VPlan after VPlanTransforms::createInterleaveGroups
+; CHECK: VPlan after VPlanTransforms::replaceSymbolicStrides
+; CHECK: VPlan after VPlanTransforms::dropPoisonGeneratingRecipes
+; CHECK: VPlan after VPlanTransforms::adjustFixedOrderRecurrences
+; CHECK: VPlan after VPlanTransforms::truncateToMinimalBitwidths
+; CHECK: VPlan after removeRedundantCanonicalIVs
+; CHECK: VPlan after removeRedundantInductionCasts
+; CHECK: VPlan after simplifyRecipes
+; CHECK: VPlan after removeDeadRecipes
+; CHECK: VPlan after simplifyBlends
+; CHECK: VPlan after legalizeAndOptimizeInductions
+; CHECK: VPlan after narrowToSingleScalarRecipes
+; CHECK: VPlan after removeRedundantExpandSCEVRecipes
+; CHECK: VPlan after simplifyRecipes
+; CHECK: VPlan after removeBranchOnConst
+; CHECK: VPlan after removeDeadRecipes
+; CHECK: VPlan after createAndOptimizeReplicateRegions
+; CHECK: VPlan after hoistInvariantLoads
+; CHECK: VPlan after mergeBlocksIntoPredecessors
+; CHECK: VPlan after licm
+; CHECK: VPlan after VPlanTransforms::optimize
+; CHECK: VPlan after VPlanTransforms::materializeConstantVectorTripCount
+; CHECK: VPlan after VPlanTransforms::unrollByUF
+; CHECK: VPlan after VPlanTransforms::materializePacksAndUnpacks
+; CHECK: VPlan after VPlanTransforms::materializeBroadcasts
+; CHECK: VPlan after VPlanTransforms::replicateByVF
+; CHECK: VPlan after printFinalVPlan
+; Also verify that VPlan is actually printed:
+; CHECK-NEXT: VPlan 'Final VPlan for VF={4},UF={1}' {
+; CHECK-NEXT: Live-in ir<%smax> = original trip-count
+; CHECK-EMPTY:
+; CHECK-NEXT: ir-bb<entry>:
+; CHECK-NEXT:   IR   %smax = call i64 @llvm.smax.i64(i64 %n, i64 1)
+; CHECK-NEXT:   EMIT vp<%min.iters.check> = icmp ult ir<%smax>, ir<4>
+; CHECK-NEXT:   EMIT branch-on-cond vp<%min.iters.check>
+; CHECK-NEXT: Successor(s): ir-bb<scalar.ph>, vector.ph
+; CHECK-EMPTY:
+; CHECK-NEXT: vector.ph:
+; CHECK-NEXT:   EMIT vp<%n.mod.vf> = urem ir<%smax>, ir<4>
+; CHECK-NEXT:   EMIT vp<%n.vec> = sub ir<%smax>, vp<%n.mod.vf>
+; CHECK-NEXT:   EMIT vp<%3> = step-vector i64
----------------
eas wrote:

Since we aren't testing the exact printing of a VPlan here (that exists in `vplan-printing.ll`), I've updated the checks to just check for the presence of a VPlan dump. I've also used a separate `RUN` line to ease future updates of this test when more transformations are run through `RUN_VPLAN_PASS` (so that one could just copy-paste `grep "VPlan after"` lines with no dumps in between).

https://github.com/llvm/llvm-project/pull/175839