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authorLogan Chien <loganchien@google.com>2011-10-20 00:08:13 +0800
committerLogan Chien <loganchien@google.com>2011-10-20 00:09:35 +0800
commit0ebc07a576037e4e36f68bf5cece32740ca120c0 (patch)
treec2e40648043d01498ee25af839a071193561e425 /lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
parent62383e889e0b06fd12a6b88311717cd33a1925c4 (diff)
parentcdd8e46bec4e975d00a5abea808d8eb4138515c5 (diff)
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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.cpp47
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);
}
}
}