Implement ((A|B)&1)|(B&-2) -> (A&1) | B transformation. This also takes care of
permutations of this pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60312 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 9cb1875..4e2e8a4 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -4649,6 +4649,73 @@
}
}
+ // ((A|B)&1)|(B&-2) -> (A&1) | B
+ if (match(Op0, m_And(m_Or(m_Value(A), m_Value(B)), m_Value(C))) ||
+ match(Op0, m_And(m_Value(C), m_Or(m_Value(A), m_Value(B))))) {
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) {
+ if (CI->getValue() == 1) {
+ Value *V1 = 0, *C2 = 0;
+ if (match(Op1, m_And(m_Value(V1), m_Value(C2)))) {
+ ConstantInt *CI2 = dyn_cast<ConstantInt>(C2);
+
+ if (!CI2) {
+ std::swap(V1, C2);
+ CI2 = dyn_cast<ConstantInt>(C2);
+ }
+
+ if (CI2) {
+ APInt NegTwo = -APInt(CI2->getValue().getBitWidth(), 2, true);
+ if (CI2->getValue().eq(NegTwo)) {
+ if (V1 == B) {
+ Instruction *NewOp =
+ InsertNewInstBefore(BinaryOperator::CreateAnd(A, CI), I);
+ return BinaryOperator::CreateOr(NewOp, B);
+ }
+ if (V1 == A) {
+ Instruction *NewOp =
+ InsertNewInstBefore(BinaryOperator::CreateAnd(B, CI), I);
+ return BinaryOperator::CreateOr(NewOp, A);
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ // (B&-2)|((A|B)&1) -> (A&1) | B
+ if (match(Op1, m_And(m_Or(m_Value(A), m_Value(B)), m_Value(C))) ||
+ match(Op1, m_And(m_Value(C), m_Or(m_Value(A), m_Value(B))))) {
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) {
+ if (CI->getValue() == 1) {
+ Value *V1 = 0, *C2 = 0;
+ if (match(Op0, m_And(m_Value(V1), m_Value(C2)))) {
+ ConstantInt *CI2 = dyn_cast<ConstantInt>(C2);
+
+ if (!CI2) {
+ std::swap(V1, C2);
+ CI2 = dyn_cast<ConstantInt>(C2);
+ }
+
+ if (CI2) {
+ APInt NegTwo = -APInt(CI2->getValue().getBitWidth(), 2, true);
+ if (CI2->getValue().eq(NegTwo)) {
+ if (V1 == B) {
+ Instruction *NewOp =
+ InsertNewInstBefore(BinaryOperator::CreateAnd(A, CI), I);
+ return BinaryOperator::CreateOr(NewOp, B);
+ }
+ if (V1 == A) {
+ Instruction *NewOp =
+ InsertNewInstBefore(BinaryOperator::CreateAnd(B, CI), I);
+ return BinaryOperator::CreateOr(NewOp, A);
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+
if (match(Op0, m_Not(m_Value(A)))) { // ~A | Op1
if (A == Op1) // ~A | A == -1
return ReplaceInstUsesWith(I, Constant::getAllOnesValue(I.getType()));