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| author | Chris Lattner <sabre@nondot.org> | 2008-01-13 20:59:02 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2008-01-13 20:59:02 +0000 |
| commit | 5bc253c8f2a8338f71b09462109859d7aae99029 (patch) | |
| tree | 5af76de91711665e2deb6f43cc6c2b4e9a952c94 /llvm/lib/Transforms | |
| parent | 93ebe1df270306de9e2a00d5a608f7a8a22ef4c1 (diff) | |
| download | bcm5719-llvm-5bc253c8f2a8338f71b09462109859d7aae99029.tar.gz bcm5719-llvm-5bc253c8f2a8338f71b09462109859d7aae99029.zip | |
Fix PR1907, a nasty miscompilation because instcombine didn't
realize that ne & sgt was a signed comparison (it was only
looking at whether the left compare was signed).
llvm-svn: 45937
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/InstructionCombining.cpp | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp index ea53aec76cb..9465a31d29d 100644 --- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp @@ -3495,8 +3495,14 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { ICmpInst::isSignedPredicate(LHSCC) == ICmpInst::isSignedPredicate(RHSCC))) { // Ensure that the larger constant is on the RHS. - ICmpInst::Predicate GT = ICmpInst::isSignedPredicate(LHSCC) ? - ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; + ICmpInst::Predicate GT; + if (ICmpInst::isSignedPredicate(LHSCC) || + (ICmpInst::isEquality(LHSCC) && + ICmpInst::isSignedPredicate(RHSCC))) + GT = ICmpInst::ICMP_SGT; + else + GT = ICmpInst::ICMP_UGT; + Constant *Cmp = ConstantExpr::getICmp(GT, LHSCst, RHSCst); ICmpInst *LHS = cast<ICmpInst>(Op0); if (cast<ConstantInt>(Cmp)->getZExtValue()) { |
