diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index ae8865651ece..a8f2cd79830a 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -1771,6 +1771,16 @@ Instruction *InstCombinerImpl::visitAnd(BinaryOperator &I) { return new ZExtInst(IsZero, Ty); } + // (-(X & 1)) & Y --> (X & 1) == 0 ? 0 : Y + Value *Neg; + if (match(&I, + m_c_And(m_CombineAnd(m_Value(Neg), + m_OneUse(m_Neg(m_And(m_Value(), m_One())))), + m_Value(Y)))) { + Value *Cmp = Builder.CreateIsNull(Neg); + return SelectInst::Create(Cmp, ConstantInt::getNullValue(Ty), Y); + } + const APInt *C; if (match(Op1, m_APInt(C))) { const APInt *XorC; @@ -1798,7 +1808,8 @@ Instruction *InstCombinerImpl::visitAnd(BinaryOperator &I) { unsigned Width = Ty->getScalarSizeInBits(); const APInt *ShiftC; - if (match(Op0, m_OneUse(m_SExt(m_AShr(m_Value(X), m_APInt(ShiftC)))))) { + if (match(Op0, m_OneUse(m_SExt(m_AShr(m_Value(X), m_APInt(ShiftC))))) && + ShiftC->ult(Width)) { if (*C == APInt::getLowBitsSet(Width, Width - ShiftC->getZExtValue())) { // We are clearing high bits that were potentially set by sext+ashr: // and (sext (ashr X, ShiftC)), C --> lshr (sext X), ShiftC |