//===---------------------------------------------------------------------===//
-This should be optimized to one 'and' and one 'or', from PR4216:
-
-define i32 @test_bitfield(i32 %bf.prev.low) nounwind ssp {
-entry:
- %bf.prev.lo.cleared10 = or i32 %bf.prev.low, 32962 ; <i32> [#uses=1]
- %0 = and i32 %bf.prev.low, -65536 ; <i32> [#uses=1]
- %1 = and i32 %bf.prev.lo.cleared10, 40186 ; <i32> [#uses=1]
- %2 = or i32 %1, %0 ; <i32> [#uses=1]
- ret i32 %2
-}
-
-//===---------------------------------------------------------------------===//
-
This isn't recognized as bswap by instcombine (yes, it really is bswap):
unsigned long reverse(unsigned v) {
return ReplaceInstUsesWith(I, B);
}
}
- V1 = 0; V2 = 0; V3 = 0;
+
+ // ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
+ // iff (C1&C2) == 0 and (N&~C1) == 0
+ if ((C1->getValue() & C2->getValue()) == 0) {
+ if (match(A, m_Or(m_Value(V1), m_Value(V2))) &&
+ ((V1 == B && MaskedValueIsZero(V2, ~C1->getValue())) || // (V|N)
+ (V2 == B && MaskedValueIsZero(V1, ~C1->getValue())))) // (N|V)
+ return BinaryOperator::CreateAnd(A,
+ ConstantInt::get(A->getContext(),
+ C1->getValue()|C2->getValue()));
+ // Or commutes, try both ways.
+ if (match(B, m_Or(m_Value(V1), m_Value(V2))) &&
+ ((V1 == A && MaskedValueIsZero(V2, ~C2->getValue())) || // (V|N)
+ (V2 == A && MaskedValueIsZero(V1, ~C2->getValue())))) // (N|V)
+ return BinaryOperator::CreateAnd(B,
+ ConstantInt::get(B->getContext(),
+ C1->getValue()|C2->getValue()));
+ }
}
// Check to see if we have any common things being and'ed. If so, find the
// terms for V1 & (V2|V3).
if (isOnlyUse(Op0) || isOnlyUse(Op1)) {
+ V1 = 0;
if (A == B) // (A & C)|(A & D) == A & (C|D)
V1 = A, V2 = C, V3 = D;
else if (A == D) // (A & C)|(B & A) == A & (B|C)