Index: llvm/trunk/lib/Analysis/InstructionSimplify.cpp =================================================================== --- llvm/trunk/lib/Analysis/InstructionSimplify.cpp +++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp @@ -1886,15 +1886,21 @@ // (A & ~B) | (A ^ B) -> (A ^ B) // (~B & A) | (A ^ B) -> (A ^ B) - if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B)))) && - match(Op1, m_Xor(m_Specific(A), m_Specific(B)))) + // (A & ~B) | (B ^ A) -> (B ^ A) + // (~B & A) | (B ^ A) -> (B ^ A) + if (match(Op1, m_Xor(m_Value(A), m_Value(B))) && + (match(Op0, m_c_And(m_Specific(A), m_Not(m_Specific(B)))) || + match(Op0, m_c_And(m_Not(m_Specific(A)), m_Specific(B))))) return Op1; // Commute the 'or' operands. // (A ^ B) | (A & ~B) -> (A ^ B) // (A ^ B) | (~B & A) -> (A ^ B) - if (match(Op1, m_c_And(m_Value(A), m_Not(m_Value(B)))) && - match(Op0, m_Xor(m_Specific(A), m_Specific(B)))) + // (B ^ A) | (A & ~B) -> (B ^ A) + // (B ^ A) | (~B & A) -> (B ^ A) + if (match(Op0, m_Xor(m_Value(A), m_Value(B))) && + (match(Op1, m_c_And(m_Specific(A), m_Not(m_Specific(B)))) || + match(Op1, m_c_And(m_Not(m_Specific(A)), m_Specific(B))))) return Op0; if (auto *ICILHS = dyn_cast(Op0)) { Index: llvm/trunk/test/Transforms/InstSimplify/AndOrXor.ll =================================================================== --- llvm/trunk/test/Transforms/InstSimplify/AndOrXor.ll +++ llvm/trunk/test/Transforms/InstSimplify/AndOrXor.ll @@ -521,3 +521,65 @@ ret i32 %or } +; (~A & ~B) | (~A ^ B) -> ~A ^ B + +define i32 @test45(i32 %a, i32 %b) { +; CHECK-LABEL: @test45( +; CHECK-NEXT: [[NEGB:%.*]] = xor i32 [[B:%.*]], -1 +; CHECK-NEXT: [[XOR:%.*]] = xor i32 [[A:%.*]], [[NEGB]] +; CHECK-NEXT: ret i32 [[XOR]] +; + %nega = xor i32 %a, -1 + %negb = xor i32 %b, -1 + %and = and i32 %nega, %negb + %xor = xor i32 %a, %negb + %or = or i32 %and, %xor + ret i32 %or +} + +define i32 @test45_commuted_and(i32 %a, i32 %b) { +; CHECK-LABEL: @test45( +; CHECK-NEXT: [[NEGB:%.*]] = xor i32 [[B:%.*]], -1 +; CHECK-NEXT: [[XOR:%.*]] = xor i32 [[A:%.*]], [[NEGB]] +; CHECK-NEXT: ret i32 [[XOR]] +; + %nega = xor i32 %a, -1 + %negb = xor i32 %b, -1 + %and = and i32 %negb, %nega + %xor = xor i32 %a, %negb + %or = or i32 %and, %xor + ret i32 %or +} + +; Commute operands of the 'or'. +; (~A ^ B) | (~A & ~B) -> ~A ^ B + +define i32 @test46(i32 %a, i32 %b) { +; CHECK-LABEL: @test46( +; CHECK-NEXT: [[NEGB:%.*]] = xor i32 [[B:%.*]], -1 +; CHECK-NEXT: [[XOR:%.*]] = xor i32 [[A:%.*]], [[NEGB]] +; CHECK-NEXT: ret i32 [[XOR]] +; + %nega = xor i32 %a, -1 + %negb = xor i32 %b, -1 + %and = and i32 %nega, %negb + %xor = xor i32 %a, %negb + %or = or i32 %xor, %and + ret i32 %or +} + +; (~A & ~B) | (~A ^ B) -> ~A ^ B + +define i32 @test46_commuted_and(i32 %a, i32 %b) { +; CHECK-LABEL: @test45( +; CHECK-NEXT: [[NEGB:%.*]] = xor i32 [[B:%.*]], -1 +; CHECK-NEXT: [[XOR:%.*]] = xor i32 [[A:%.*]], [[NEGB]] +; CHECK-NEXT: ret i32 [[XOR]] +; + %nega = xor i32 %a, -1 + %negb = xor i32 %b, -1 + %and = and i32 %negb, %nega + %xor = xor i32 %a, %negb + %or = or i32 %xor, %and + ret i32 %or +}