diff options
| author | Dan Gohman <gohman@apple.com> | 2009-12-18 18:45:31 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-12-18 18:45:31 +0000 |
| commit | 59de33ef3934eb98f0c5dfbfb2c56fb4b80bda56 (patch) | |
| tree | 9daf149b5b131e3f658baab918e6808d9de40640 /lib/Analysis/ScalarEvolution.cpp | |
| parent | fda60d35c247c239857ebaae8650b06f1154e68e (diff) | |
| download | llvm-59de33ef3934eb98f0c5dfbfb2c56fb4b80bda56.tar.gz llvm-59de33ef3934eb98f0c5dfbfb2c56fb4b80bda56.tar.bz2 llvm-59de33ef3934eb98f0c5dfbfb2c56fb4b80bda56.tar.xz | |
Revert this use of NUW/NSW also. Overflow-undefined multiplication isn't
associative either.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91701 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis/ScalarEvolution.cpp')
| -rw-r--r-- | lib/Analysis/ScalarEvolution.cpp | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index 3c937e05cc..ec901b77cc 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -1460,7 +1460,10 @@ const SCEV *ScalarEvolution::getAddExpr(SmallVectorImpl<const SCEV *> &Ops, AddRec->op_end()); AddRecOps[0] = getAddExpr(LIOps); + // It's tempting to propogate NUW/NSW flags here, but nuw/nsw addition + // is not associative so this isn't necessarily safe. const SCEV *NewRec = getAddRecExpr(AddRecOps, AddRec->getLoop()); + // If all of the other operands were loop invariant, we are done. if (Ops.size() == 1) return NewRec; @@ -1636,9 +1639,9 @@ const SCEV *ScalarEvolution::getMulExpr(SmallVectorImpl<const SCEV *> &Ops, } } - const SCEV *NewRec = getAddRecExpr(NewOps, AddRec->getLoop(), - AddRec->hasNoUnsignedWrap() && HasNUW, - AddRec->hasNoSignedWrap() && HasNSW); + // It's tempting to propogate NUW/NSW flags here, but nuw/nsw multiplication + // is not associative so this isn't necessarily safe. + const SCEV *NewRec = getAddRecExpr(NewOps, AddRec->getLoop()); // If all of the other operands were loop invariant, we are done. if (Ops.size() == 1) return NewRec; |