diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp index ea7942ef9781..7a184a19d7c5 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -1289,7 +1289,7 @@ static Instruction *foldAddToAshr(BinaryOperator &Add) { // Note that, by the time we end up here, if possible, ugt has been // canonicalized into eq. const APInt *MaskC, *MaskCCmp; - ICmpInst::Predicate Pred; + CmpPredicate Pred; if (!match(Add.getOperand(1), m_SExt(m_ICmp(Pred, m_And(m_Specific(X), m_APInt(MaskC)), m_APInt(MaskCCmp))))) @@ -1382,7 +1382,7 @@ Instruction *InstCombinerImpl:: // `select` itself may be appropriately extended, look past that. SkipExtInMagic(Select); - ICmpInst::Predicate Pred; + CmpPredicate Pred; const APInt *Thr; Value *SignExtendingValue, *Zero; bool ShouldSignext; @@ -1654,7 +1654,7 @@ Instruction *InstCombinerImpl::visitAdd(BinaryOperator &I) { return replaceInstUsesWith(I, Constant::getNullValue(I.getType())); // sext(A < B) + zext(A > B) => ucmp/scmp(A, B) - ICmpInst::Predicate LTPred, GTPred; + CmpPredicate LTPred, GTPred; if (match(&I, m_c_Add(m_SExt(m_c_ICmp(LTPred, m_Value(A), m_Value(B))), m_ZExt(m_c_ICmp(GTPred, m_Deferred(A), m_Deferred(B))))) && @@ -1841,7 +1841,7 @@ Instruction *InstCombinerImpl::visitAdd(BinaryOperator &I) { // --> // BW - ctlz(A - 1, false) const APInt *XorC; - ICmpInst::Predicate Pred; + CmpPredicate Pred; if (match(&I, m_c_Add( m_ZExt(m_ICmp(Pred, m_Intrinsic<Intrinsic::ctpop>(m_Value(A)), @@ -2280,6 +2280,16 @@ Instruction *InstCombinerImpl::visitSub(BinaryOperator &I) { if (match(Op0, m_OneUse(m_Add(m_Value(X), m_AllOnes())))) return BinaryOperator::CreateAdd(Builder.CreateNot(Op1), X); + // if (C1 & C2) == C2 then (X & C1) - (X & C2) -> X & (C1 ^ C2) + Constant *C1, *C2; + if (match(Op0, m_And(m_Value(X), m_ImmConstant(C1))) && + match(Op1, m_And(m_Specific(X), m_ImmConstant(C2)))) { + Value *AndC = ConstantFoldBinaryInstruction(Instruction::And, C1, C2); + if (C2->isElementWiseEqual(AndC)) + return BinaryOperator::CreateAnd( + X, ConstantFoldBinaryInstruction(Instruction::Xor, C1, C2)); + } + // Reassociate sub/add sequences to create more add instructions and // reduce dependency chains: // ((X - Y) + Z) - Op1 --> (X + Z) - (Y + Op1) |