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| author | Sanjoy Das <sanjoy@playingwithpointers.com> | 2015-12-08 00:13:17 +0000 |
|---|---|---|
| committer | Sanjoy Das <sanjoy@playingwithpointers.com> | 2015-12-08 00:13:17 +0000 |
| commit | b771eb6d69bf86a62d336d9bbe22b6b5757f1984 (patch) | |
| tree | 6bb3b5ad2515ed20b7b8e5113748b50add36bc96 /llvm/lib/Analysis/ScalarEvolutionExpander.cpp | |
| parent | 411fdcd460312b4b441bda60c138d9877f2d426e (diff) | |
| download | llvm-b771eb6d69bf86a62d336d9bbe22b6b5757f1984.zip llvm-b771eb6d69bf86a62d336d9bbe22b6b5757f1984.tar.gz llvm-b771eb6d69bf86a62d336d9bbe22b6b5757f1984.tar.bz2 | |
[SCEVExpander] Have hoistIVInc preserve LCSSA
Summary:
(Note: the problematic invocation of hoistIVInc that caused PR24804 came
from IndVarSimplify, not from SCEVExpander itself)
Fixes PR24804. Test case by David Majnemer.
Reviewers: hfinkel, majnemer, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15058
llvm-svn: 254976
Diffstat (limited to 'llvm/lib/Analysis/ScalarEvolutionExpander.cpp')
| -rw-r--r-- | llvm/lib/Analysis/ScalarEvolutionExpander.cpp | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp index 8c5805e..abfcfba 100644 --- a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp @@ -933,6 +933,9 @@ bool SCEVExpander::hoistIVInc(Instruction *IncV, Instruction *InsertPos) { !SE.DT.dominates(InsertPos->getParent(), IncV->getParent())) return false; + if (!SE.LI.movementPreservesLCSSAForm(IncV, InsertPos)) + return false; + // Check that the chain of IV operands leading back to Phi can be hoisted. SmallVector<Instruction*, 4> IVIncs; for(;;) { |