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Use m_Specific() instead of double matching. 

llvm-svn: 60341
This commit is contained in:
Bill Wendling 2008-12-01 08:09:47 +00:00
parent 4eecfb655b
commit 582fe6b0ca
2 changed files with 13 additions and 19 deletions
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30
llvm/lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -4603,28 +4603,22 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
if (Instruction *Match = MatchSelectFromAndOr(D, A, B, C))
return Match;
V1 = V2 = 0;
// ((A&~B)|(~A&B)) -> A^B
if ((match(C, m_Not(m_Value(V1))) &&
match(B, m_Not(m_Value(V2)))))
if (V1 == D && V2 == A)
return BinaryOperator::CreateXor(V1, V2);
if ((match(C, m_Not(m_Specific(D))) &&
match(B, m_Not(m_Specific(A)))))
return BinaryOperator::CreateXor(A, D);
// ((~B&A)|(~A&B)) -> A^B
if ((match(A, m_Not(m_Value(V1))) &&
match(B, m_Not(m_Value(V2)))))
if (V1 == D && V2 == C)
return BinaryOperator::CreateXor(V1, V2);
if ((match(A, m_Not(m_Specific(D))) &&
match(B, m_Not(m_Specific(C)))))
return BinaryOperator::CreateXor(C, D);
// ((A&~B)|(B&~A)) -> A^B
if ((match(C, m_Not(m_Value(V1))) &&
match(D, m_Not(m_Value(V2)))))
if (V1 == B && V2 == A)
return BinaryOperator::CreateXor(V1, V2);
if ((match(C, m_Not(m_Specific(B))) &&
match(D, m_Not(m_Specific(A)))))
return BinaryOperator::CreateXor(A, B);
// ((~B&A)|(B&~A)) -> A^B
if ((match(A, m_Not(m_Value(V1))) &&
match(D, m_Not(m_Value(V2)))))
if (V1 == B && V2 == C)
return BinaryOperator::CreateXor(V1, V2);
if ((match(A, m_Not(m_Specific(B))) &&
match(D, m_Not(m_Specific(C)))))
return BinaryOperator::CreateXor(C, B);
}
// (X >> Z) | (Y >> Z) -> (X|Y) >> Z for all shifts.

2
llvm/test/Transforms/InstCombine/or-to-xor.ll
View File

@ -1,4 +1,4 @@
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {xor i32 %b, %a} | count 4
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {xor i32 %a, %b} | count 4
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep {and}
define i32 @func1(i32 %a, i32 %b) nounwind readnone {