diff options
| author | Nick Lewycky <nicholas@mxc.ca> | 2013-07-12 23:42:57 +0000 |
|---|---|---|
| committer | Nick Lewycky <nicholas@mxc.ca> | 2013-07-12 23:42:57 +0000 |
| commit | 35aeea993b091164f202266a4969d6f6df2adc7f (patch) | |
| tree | 77f404c05d1141a65ca6ad05191e6d5d6cb3fb96 /llvm/lib/Analysis/InstructionSimplify.cpp | |
| parent | d2a507a6e693b878f50bb1b43500d59721adc5ed (diff) | |
| download | bcm5719-llvm-35aeea993b091164f202266a4969d6f6df2adc7f.tar.gz bcm5719-llvm-35aeea993b091164f202266a4969d6f6df2adc7f.zip | |
Fix logic error optimizing "icmp pred (urem X, Y), Y" where pred is signed.
Fixes PR16605.
llvm-svn: 186229
Diffstat (limited to 'llvm/lib/Analysis/InstructionSimplify.cpp')
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index d66ecca928a..52c04565862 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -2246,6 +2246,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, } } + // icmp pred (urem X, Y), Y if (LBO && match(LBO, m_URem(m_Value(), m_Specific(RHS)))) { bool KnownNonNegative, KnownNegative; switch (Pred) { @@ -2253,7 +2254,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, break; case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_SGE: - ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); + ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); if (!KnownNonNegative) break; // fall-through @@ -2263,7 +2264,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, return getFalse(ITy); case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_SLE: - ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); + ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); if (!KnownNonNegative) break; // fall-through @@ -2273,6 +2274,8 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, return getTrue(ITy); } } + + // icmp pred X, (urem Y, X) if (RBO && match(RBO, m_URem(m_Value(), m_Specific(LHS)))) { bool KnownNonNegative, KnownNegative; switch (Pred) { @@ -2280,7 +2283,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, break; case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_SGE: - ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); + ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); if (!KnownNonNegative) break; // fall-through @@ -2290,7 +2293,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, return getTrue(ITy); case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_SLE: - ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); + ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); if (!KnownNonNegative) break; // fall-through |
