maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[MemorySSA] LoopSimplify preserves MemorySSA only when flag is flipped. 

LoopSimplify can preserve MemorySSA after r360270.
But the MemorySSA analysis is retrieved and preserved only when the
EnableMSSALoopDependency is set to true. Use the same conditional to
mark the pass as preserved, otherwise subsequent passes will get an
invalid analysis.
Resolves PR41853.

llvm-svn: 360697
This commit is contained in:
Alina Sbirlea 2019-05-14 18:07:18 +00:00
parent 75ad8c5d63
commit 80c6e79602
2 changed files with 18 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
llvm/lib/Transforms/Utils/LoopSimplify.cpp
View File

@ -768,6 +768,7 @@ namespace {
AU.addPreserved<DependenceAnalysisWrapperPass>();
AU.addPreservedID(BreakCriticalEdgesID); // No critical edges added.
AU.addPreserved<BranchProbabilityInfoWrapperPass>();
if (EnableMSSALoopDependency)
AU.addPreserved<MemorySSAWrapperPass>();
}

16
llvm/test/Analysis/MemorySSA/pr41853.ll Normal file
View File

@ -0,0 +1,16 @@
; RUN: opt -S -memoryssa -loop-simplify -early-cse-memssa -verify-memoryssa %s | FileCheck %s
; RUN: opt -S -memoryssa -loop-simplify -early-cse-memssa -enable-mssa-loop-dependency -verify-memoryssa %s | FileCheck %s
; REQUIRES: asserts
target triple = "x86_64-unknown-linux-gnu"
; CHECK-LABEL: @func()
define void @func() {
br i1 undef, label %bb5, label %bb3
bb5: ; preds = %bb5, %0
store i16 undef, i16* undef
br i1 undef, label %bb5, label %bb3
bb3: ; preds = %bb5, %0
ret void
}