diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 56786b8e7b..12523cd3fe 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -4028,6 +4028,10 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { case ICmpInst::ICMP_EQ: // (X u< 13 | X == 14) -> no change break; case ICmpInst::ICMP_UGT: // (X u< 13 | X u> 15) ->(X-13) u> 2 + // If RHSCst is [us]MAXINT, it is always false. Not handling + // this can cause overflow. + if (RHSCst->isMaxValue(false)) + return ReplaceInstUsesWith(I, LHS); return InsertRangeTest(LHSVal, LHSCst, AddOne(RHSCst), false, false, I); case ICmpInst::ICMP_SGT: // (X u< 13 | X s> 15) -> no change @@ -4045,6 +4049,10 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { case ICmpInst::ICMP_EQ: // (X s< 13 | X == 14) -> no change break; case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) ->(X-13) s> 2 + // If RHSCst is [us]MAXINT, it is always false. Not handling + // this can cause overflow. + if (RHSCst->isMaxValue(true)) + return ReplaceInstUsesWith(I, LHS); return InsertRangeTest(LHSVal, LHSCst, AddOne(RHSCst), true, false, I); case ICmpInst::ICMP_UGT: // (X s< 13 | X u> 15) -> no change |