Index: llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp =================================================================== --- llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -2012,6 +2012,13 @@ 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_OneUse(m_c_And(m_Value(A), m_Not(m_Value(B))))) && + match(Op1, m_Not(m_Value(C)))) + 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 @@ -522,10 +522,9 @@ define i32 @not_and_and_not(i32 %a0, i32 %b, i32 %c) { ; CHECK-LABEL: @not_and_and_not( ; CHECK-NEXT: [[A:%.*]] = sdiv i32 42, [[A0:%.*]] -; CHECK-NEXT: [[NOT1:%.*]] = xor i32 [[B:%.*]], -1 -; CHECK-NEXT: [[NOT2:%.*]] = xor i32 [[C:%.*]], -1 -; CHECK-NEXT: [[AND1:%.*]] = and i32 [[A]], [[NOT1]] -; CHECK-NEXT: [[AND2:%.*]] = and i32 [[AND1]], [[NOT2]] +; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[B:%.*]], [[C:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 +; CHECK-NEXT: [[AND2:%.*]] = and i32 [[A]], [[TMP2]] ; CHECK-NEXT: ret i32 [[AND2]] ; %a = sdiv i32 42, %a0 ; thwart complexity-based canonicalization @@ -539,10 +538,9 @@ define <4 x i64> @not_and_and_not_4i64(<4 x i64> %a0, <4 x i64> %b, <4 x i64> %c) { ; CHECK-LABEL: @not_and_and_not_4i64( ; CHECK-NEXT: [[A:%.*]] = sdiv <4 x i64> , [[A0:%.*]] -; CHECK-NEXT: [[NOT1:%.*]] = xor <4 x i64> [[B:%.*]], -; CHECK-NEXT: [[NOT2:%.*]] = xor <4 x i64> [[C:%.*]], -; CHECK-NEXT: [[AND1:%.*]] = and <4 x i64> [[A]], [[NOT1]] -; CHECK-NEXT: [[AND2:%.*]] = and <4 x i64> [[AND1]], [[NOT2]] +; CHECK-NEXT: [[TMP1:%.*]] = or <4 x i64> [[B:%.*]], [[C:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = xor <4 x i64> [[TMP1]], +; CHECK-NEXT: [[AND2:%.*]] = and <4 x i64> [[A]], [[TMP2]] ; CHECK-NEXT: ret <4 x i64> [[AND2]] ; %a = sdiv <4 x i64> , %a0 ; thwart complexity-based canonicalization @@ -555,16 +553,13 @@ ; (~b & a) & ~c --> a & ~(b | c) -define i32 @not_and_and_not_commute1(i32 %a0, i32 %b, i32 %c) { +define i32 @not_and_and_not_commute1(i32 %a, i32 %b, i32 %c) { ; CHECK-LABEL: @not_and_and_not_commute1( -; CHECK-NEXT: [[A:%.*]] = sdiv i32 42, [[A0:%.*]] -; CHECK-NEXT: [[NOT1:%.*]] = xor i32 [[B:%.*]], -1 -; CHECK-NEXT: [[NOT2:%.*]] = xor i32 [[C:%.*]], -1 -; CHECK-NEXT: [[AND1:%.*]] = and i32 [[A]], [[NOT1]] -; CHECK-NEXT: [[AND2:%.*]] = and i32 [[AND1]], [[NOT2]] +; 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]] ; - %a = sdiv i32 42, %a0 ; thwart complexity-based canonicalization %not1 = xor i32 %b, -1 %not2 = xor i32 %c, -1 %and1 = and i32 %not1, %a @@ -574,19 +569,41 @@ ; ~c & (a & ~b) --> a & ~(b | c) -define i32 @not_and_and_not_commute2(i32 %a0, i32 %b, i32 %c) { -; CHECK-LABEL: @not_and_and_not_commute2( +declare void @use(i32) +define i32 @not_and_and_not_commute2_extra_not_use(i32 %a0, i32 %b, i32 %c) { +; CHECK-LABEL: @not_and_and_not_commute2_extra_not_use( +; CHECK-NEXT: [[A:%.*]] = sdiv i32 42, [[A0:%.*]] +; CHECK-NEXT: [[NOT2:%.*]] = xor i32 [[C:%.*]], -1 +; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[B:%.*]], [[C]] +; CHECK-NEXT: [[TMP2:%.*]] = xor i32 [[TMP1]], -1 +; CHECK-NEXT: [[AND2:%.*]] = and i32 [[A]], [[TMP2]] +; CHECK-NEXT: call void @use(i32 [[NOT2]]) +; CHECK-NEXT: ret i32 [[AND2]] +; + %a = sdiv i32 42, %a0 ; thwart complexity-based canonicalization + %not1 = xor i32 %b, -1 + %not2 = xor i32 %c, -1 + %and1 = and i32 %a, %not1 + %and2 = and i32 %not2, %and1 + call void @use(i32 %not2) + ret i32 %and2 +} + +define i32 @not_and_and_not_extra_and1_use(i32 %a0, i32 %b, i32 %c) { +; CHECK-LABEL: @not_and_and_not_extra_and1_use( ; CHECK-NEXT: [[A:%.*]] = sdiv i32 42, [[A0:%.*]] ; CHECK-NEXT: [[NOT1:%.*]] = xor i32 [[B:%.*]], -1 ; CHECK-NEXT: [[NOT2:%.*]] = xor i32 [[C:%.*]], -1 ; CHECK-NEXT: [[AND1:%.*]] = and i32 [[A]], [[NOT1]] ; CHECK-NEXT: [[AND2:%.*]] = and i32 [[AND1]], [[NOT2]] +; CHECK-NEXT: call void @use(i32 [[AND1]]) ; CHECK-NEXT: ret i32 [[AND2]] ; %a = sdiv i32 42, %a0 ; thwart complexity-based canonicalization %not1 = xor i32 %b, -1 %not2 = xor i32 %c, -1 %and1 = and i32 %a, %not1 - %and2 = and i32 %not2, %and1 + %and2 = and i32 %and1, %not2 + call void @use(i32 %and1) ret i32 %and2 }