Index: llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp =================================================================== --- llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -2012,6 +2012,22 @@ if (match(Op0, m_c_Xor(m_Not(m_Value(A)), m_Value(B))) && match(Op1, m_c_Or(m_Specific(A), m_Specific(B)))) return BinaryOperator::CreateAnd(A, B); + + // (A & ~B) & ~C -> A & ~(B | C) + // (~B & A) & ~C -> A & ~(B | C) + if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B))))) + if (match(Op1, m_Not(m_Value(C)))) + if (Op0->hasOneUse()) + return BinaryOperator::CreateAnd( + A, Builder.CreateNot(Builder.CreateOr(B, C))); + + // ~C & (A & ~B) -> A & ~(B | C) + // ~C & (~B & A) -> A & ~(B | C) + if (match(Op1, m_c_And(m_Value(A), m_Not(m_Value(B))))) + if (match(Op0, m_Not(m_Value(C)))) + if (Op0->hasOneUse()) + return BinaryOperator::CreateAnd( + A, Builder.CreateNot(Builder.CreateOr(B, C))); } { Index: llvm/test/Transforms/InstCombine/and-xor-or.ll =================================================================== --- llvm/test/Transforms/InstCombine/and-xor-or.ll +++ llvm/test/Transforms/InstCombine/and-xor-or.ll @@ -516,3 +516,51 @@ %use2 = udiv i64 %or2, %use1 ret i64 %use2 } + +; (a & ~b) & ~c --> a & ~(b | c) + +define i32 @not_and_and_not(i32 %a, i32 %b, i32 %c) { +; CHECK-LABEL: @not_and_and_not( +; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[B:%.*]], [[C:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 +; CHECK-NEXT: [[AND2:%.*]] = and i32 [[TMP2]], [[A:%.*]] +; CHECK-NEXT: ret i32 [[AND2]] +; + %not1 = xor i32 %b, -1 + %not2 = xor i32 %c, -1 + %and1 = and i32 %a, %not1 + %and2 = and i32 %and1, %not2 + ret i32 %and2 +} + +; (~b & a) & ~c --> a & ~(b | c) + +define i32 @not_and_and_not_commute1(i32 %a, i32 %b, i32 %c) { +; CHECK-LABEL: @not_and_and_not_commute1( +; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[B:%.*]], [[C:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 +; CHECK-NEXT: [[AND2:%.*]] = and i32 [[TMP2]], [[A:%.*]] +; CHECK-NEXT: ret i32 [[AND2]] +; + %not1 = xor i32 %b, -1 + %not2 = xor i32 %c, -1 + %and1 = and i32 %not1, %a + %and2 = and i32 %and1, %not2 + ret i32 %and2 +} + +; ~c & (a & ~b) --> a & ~(b | c) + +define i32 @not_and_and_not_commute2(i32 %a, i32 %b, i32 %c) { +; CHECK-LABEL: @not_and_and_not_commute2( +; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[B:%.*]], [[C:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 +; CHECK-NEXT: [[AND2:%.*]] = and i32 [[TMP2]], [[A:%.*]] +; CHECK-NEXT: ret i32 [[AND2]] +; + %not1 = xor i32 %b, -1 + %not2 = xor i32 %c, -1 + %and1 = and i32 %a, %not1 + %and2 = and i32 %not2, %and1 + ret i32 %and2 +}