[llvm] [LV] Provide utility routine to find uncounted exit recipes (PR #152530)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,99 @@
+//===- llvm/unittests/Transforms/Vectorize/VPlanUncountedExitTest.cpp -----===//
+//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "../lib/Transforms/Vectorize/LoopVectorizationPlanner.h"
+#include "../lib/Transforms/Vectorize/VPlan.h"
+#include "../lib/Transforms/Vectorize/VPlanPatternMatch.h"
+#include "../lib/Transforms/Vectorize/VPlanUtils.h"
+#include "VPlanTestBase.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/Instructions.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+
+namespace {
+class VPUncountedExitTest : public VPlanTestBase {};
+
+TEST_F(VPUncountedExitTest, FindUncountedExitRecipes) {
+  // Create CFG skeleton.
+  VPlan &Plan = getPlan();
+  VPBasicBlock *ScalarPH = Plan.getEntry();
+  VPBasicBlock *Entry = Plan.createVPBasicBlock("entry");
+  Plan.setEntry(Entry);
+  VPBasicBlock *VectorPH = Plan.createVPBasicBlock("vector.ph");
+  VPBasicBlock *VecBody = Plan.createVPBasicBlock("vector.body");
+  VPRegionBlock *Region =
+      Plan.createVPRegionBlock(VecBody, VecBody, "vector loop");
+  VPBasicBlock *MiddleBlock = Plan.createVPBasicBlock("middle.block");
+  VPBlockUtils::connectBlocks(Entry, ScalarPH);
+  VPBlockUtils::connectBlocks(Entry, VectorPH);
+  VPBlockUtils::connectBlocks(VectorPH, Region);
+  VPBlockUtils::connectBlocks(Region, MiddleBlock);
+  VPBlockUtils::connectBlocks(MiddleBlock, ScalarPH);
+
+  // Live-Ins
+  IntegerType *I64Ty = IntegerType::get(C, 64);
+  IntegerType *I32Ty = IntegerType::get(C, 32);
+  PointerType *PTy = PointerType::get(C, 0);
+  VPValue *Zero = Plan.getOrAddLiveIn(ConstantInt::get(I64Ty, 0));
+  VPValue *Inc = Plan.getOrAddLiveIn(ConstantInt::get(I64Ty, 1));
+  VPValue *VF = &Plan.getVF();
+  Plan.setTripCount(Plan.getOrAddLiveIn(ConstantInt::get(I64Ty, 64)));
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fhahn wrote:

Can we use VPTestBase::buildVPlan to construct the initial VPlan from a simple CFG loop and then just create convert the Load VPInstructions to VPWidenLoadRecipes? That would ensure we keep things in-sync if the constructed VPlans change.

https://github.com/llvm/llvm-project/pull/152530