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| author | Mikael Holmen <mikael.holmen@ericsson.com> | 2017-12-01 12:30:49 +0000 |
|---|---|---|
| committer | Mikael Holmen <mikael.holmen@ericsson.com> | 2017-12-01 12:30:49 +0000 |
| commit | 9f047795fbf0e9ed760e78c496179cb9552865d7 (patch) | |
| tree | b400f3a5e2e589d10c1d8a3f698181b734eabf8d /llvm/lib/Transforms/Utils/SimplifyCFG.cpp | |
| parent | 11edb4eeef299452b8e83d96e3c042b001ec803e (diff) | |
| download | bcm5719-llvm-9f047795fbf0e9ed760e78c496179cb9552865d7.tar.gz bcm5719-llvm-9f047795fbf0e9ed760e78c496179cb9552865d7.zip | |
Bail out of a SimplifyCFG switch table opt at undef values.
Summary:
A true or false result is expected from a comparison, but it seems the possibility of undef was overlooked, which could lead to a failed assert. This is fixed by this patch by bailing out if we encounter undef.
The bug is old and the assert has been there since the end of 2014, so it seems this is unusual enough to forego optimization.
Patch by: JesperAntonsson
Reviewers: spatel, eeckstein, hans
Reviewed By: hans
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40639
llvm-svn: 319537
Diffstat (limited to 'llvm/lib/Transforms/Utils/SimplifyCFG.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 8f1626a149a..394c951630c 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -5174,7 +5174,7 @@ static void reuseTableCompare( for (auto ValuePair : Values) { Constant *CaseConst = ConstantExpr::getICmp(CmpInst->getPredicate(), ValuePair.second, CmpOp1, true); - if (!CaseConst || CaseConst == DefaultConst) + if (!CaseConst || CaseConst == DefaultConst || isa<UndefValue>(CaseConst)) return; assert((CaseConst == TrueConst || CaseConst == FalseConst) && "Expect true or false as compare result."); |
