diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp index 47329fa1f043..936ab8e823df 100644 --- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -5382,10 +5382,11 @@ void LSRInstance::RewriteForPHI( // Split the critical edge. BasicBlock *NewBB = nullptr; if (!Parent->isLandingPad()) { - NewBB = SplitCriticalEdge(BB, Parent, - CriticalEdgeSplittingOptions(&DT, &LI) - .setMergeIdenticalEdges() - .setKeepOneInputPHIs()); + NewBB = + SplitCriticalEdge(BB, Parent, + CriticalEdgeSplittingOptions(&DT, &LI, MSSAU) + .setMergeIdenticalEdges() + .setKeepOneInputPHIs()); } else { SmallVector NewBBs; SplitLandingPadPredecessors(Parent, BB, "", "", NewBBs, &DT, &LI); diff --git a/llvm/test/Analysis/MemorySSA/update-remove-dead-blocks.ll b/llvm/test/Analysis/MemorySSA/update-remove-dead-blocks.ll new file mode 100644 index 000000000000..fab278784583 --- /dev/null +++ b/llvm/test/Analysis/MemorySSA/update-remove-dead-blocks.ll @@ -0,0 +1,46 @@ +; RUN: opt -loop-unswitch -loop-reduce -loop-simplifycfg -verify-memoryssa -S %s | FileCheck %s + +; TODO: also run with NPM, but currently LSR does not preserve LCSSA, causing a verification failure on the test. +; opt -passes='loop-mssa(unswitch,loop-reduce,simplify-cfg)' -verify-memoryssa -S %s | FileCheck %s + +; Test case for PR47557. + +; REQUIRES: x86-registered-target + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@a = external global i32, align 4 +@c = external global [1 x i32], align 4 + +define i32* @test() { +; CHECK-LABEL: @test +; +entry: ; preds = %entry + br label %for.cond + +for.cond: ; preds = %cleanup, %entry + %storemerge = phi i64 [ 0, %entry ], [ %inc7, %cleanup ] + br label %for.cond2.1 + +for.body3: ; preds = %for.cond2.2, %for.cond2.1 + %arrayidx = getelementptr inbounds [1 x i32], [1 x i32]* @c, i64 0, i64 %storemerge + ret i32* %arrayidx + +cleanup: ; preds = %for.end5, %if.then + %inc7 = add nsw i64 %storemerge, 1 + br label %for.cond + +for.cond2.1: ; preds = %for.cond + br i1 true, label %for.inc.1, label %for.body3 + +for.inc.1: ; preds = %for.end.1 + br i1 false, label %for.body.2, label %cleanup + +for.body.2: ; preds = %for.inc.1 + store i32 0, i32* @a, align 4 + br label %for.cond2.2 + +for.cond2.2: ; preds = %for.body.2 + br i1 true, label %cleanup, label %for.body3 +}