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| author | Logan Chien <loganchien@google.com> | 2011-10-20 00:08:13 +0800 |
|---|---|---|
| committer | Logan Chien <loganchien@google.com> | 2011-10-20 00:09:35 +0800 |
| commit | 0ebc07a576037e4e36f68bf5cece32740ca120c0 (patch) | |
| tree | c2e40648043d01498ee25af839a071193561e425 /lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | |
| parent | 62383e889e0b06fd12a6b88311717cd33a1925c4 (diff) | |
| parent | cdd8e46bec4e975d00a5abea808d8eb4138515c5 (diff) | |
| download | external_llvm-0ebc07a576037e4e36f68bf5cece32740ca120c0.zip external_llvm-0ebc07a576037e4e36f68bf5cece32740ca120c0.tar.gz external_llvm-0ebc07a576037e4e36f68bf5cece32740ca120c0.tar.bz2 | |
Merge with LLVM upstream 2011/10/20 (r142530)
Conflicts:
lib/Support/Unix/Host.inc
Change-Id: Idc00db3b63912dca6348bddd9f8a1af2a8d5d147
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineAndOrXor.cpp')
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 47 |
1 files changed, 24 insertions, 23 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 32920fa..5e0bfe8 100644 --- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -1174,30 +1174,31 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { ((A == C && B == D) || (A == D && B == C))) return BinaryOperator::CreateXor(A, B); - if (Op0->hasOneUse() && - match(Op0, m_Xor(m_Value(A), m_Value(B)))) { - if (A == Op1) { // (A^B)&A -> A&(A^B) - I.swapOperands(); // Simplify below - std::swap(Op0, Op1); - } else if (B == Op1) { // (A^B)&B -> B&(B^A) - cast<BinaryOperator>(Op0)->swapOperands(); - I.swapOperands(); // Simplify below - std::swap(Op0, Op1); + // A&(A^B) => A & ~B + { + Value *tmpOp0 = Op0; + Value *tmpOp1 = Op1; + if (Op0->hasOneUse() && + match(Op0, m_Xor(m_Value(A), m_Value(B)))) { + if (A == Op1 || B == Op1 ) { + tmpOp1 = Op0; + tmpOp0 = Op1; + // Simplify below + } } - } - if (Op1->hasOneUse() && - match(Op1, m_Xor(m_Value(A), m_Value(B)))) { - if (B == Op0) { // B&(A^B) -> B&(B^A) - cast<BinaryOperator>(Op1)->swapOperands(); - std::swap(A, B); + if (tmpOp1->hasOneUse() && + match(tmpOp1, m_Xor(m_Value(A), m_Value(B)))) { + if (B == tmpOp0) { + std::swap(A, B); + } + // Notice that the patten (A&(~B)) is actually (A&(-1^B)), so if + // A is originally -1 (or a vector of -1 and undefs), then we enter + // an endless loop. By checking that A is non-constant we ensure that + // we will never get to the loop. + if (A == tmpOp0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B + return BinaryOperator::CreateAnd(A, Builder->CreateNot(B)); } - // Notice that the patten (A&(~B)) is actually (A&(-1^B)), so if - // A is originally -1 (or a vector of -1 and undefs), then we enter - // an endless loop. By checking that A is non-constant we ensure that - // we will never get to the loop. - if (A == Op0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B - return BinaryOperator::CreateAnd(A, Builder->CreateNot(B, "tmp")); } // (A&((~A)|B)) -> A&B @@ -2227,14 +2228,14 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { if (A == Op1) // (B|A)^B == (A|B)^B std::swap(A, B); if (B == Op1) // (A|B)^B == A & ~B - return BinaryOperator::CreateAnd(A, Builder->CreateNot(Op1, "tmp")); + return BinaryOperator::CreateAnd(A, Builder->CreateNot(Op1)); } else if (match(Op0I, m_And(m_Value(A), m_Value(B))) && Op0I->hasOneUse()){ if (A == Op1) // (A&B)^A -> (B&A)^A std::swap(A, B); if (B == Op1 && // (B&A)^A == ~B & A !isa<ConstantInt>(Op1)) { // Canonical form is (B&C)^C - return BinaryOperator::CreateAnd(Builder->CreateNot(A, "tmp"), Op1); + return BinaryOperator::CreateAnd(Builder->CreateNot(A), Op1); } } } |
