diff options
Diffstat (limited to 'lib/Transforms')
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCompares.cpp | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp index 999de34097..7c67bf61b6 100644 --- a/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -1340,6 +1340,16 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI, } } break; + + case Instruction::SRem: { + bool TrueIfSigned; + if (LHSI->hasOneUse() && + isSignBitCheck(ICI.getPredicate(), RHS, TrueIfSigned)) { + // srem has the same sign as its dividend so the divisor is irrelevant. + return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0), RHS); + } + break; + } } // Simplify icmp_eq and icmp_ne instructions with integer constant RHS. @@ -1855,11 +1865,11 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) { return new ICmpInst(ICmpInst::ICMP_SLT, Op0, ConstantInt::get(CI->getContext(), CI->getValue()+1)); case ICmpInst::ICMP_UGE: - assert(!CI->isMinValue(false)); // A >=u MIN -> TRUE + assert(!CI->isMinValue(false)); // A >=u MIN -> TRUE return new ICmpInst(ICmpInst::ICMP_UGT, Op0, ConstantInt::get(CI->getContext(), CI->getValue()-1)); case ICmpInst::ICMP_SGE: - assert(!CI->isMinValue(true)); // A >=s MIN -> TRUE + assert(!CI->isMinValue(true)); // A >=s MIN -> TRUE return new ICmpInst(ICmpInst::ICMP_SGT, Op0, ConstantInt::get(CI->getContext(), CI->getValue()-1)); } @@ -1913,7 +1923,7 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) { ConstantInt::get(I.getContext(), Op1Min)); // Based on the range information we know about the LHS, see if we can - // simplify this comparison. For example, (x&4) < 8 is always true. + // simplify this comparison. For example, (x&4) < 8 is always true. switch (I.getPredicate()) { default: llvm_unreachable("Unknown icmp opcode!"); case ICmpInst::ICMP_EQ: { |