(A & sext(C)) | (B & ~sext(C) -> C ? A : B
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58351 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 8ec775b..4ec36ad 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -4337,6 +4337,25 @@
return BinaryOperator::CreateAnd(V1, Or);
}
}
+
+ // (A & sext(C0)) | (B & ~sext(C0) -> C0 ? A : B
+ if (isa<SExtInst>(C) &&
+ cast<User>(C)->getOperand(0)->getType() == Type::Int1Ty) {
+ if (match(D, m_Not(m_Value(C))))
+ return SelectInst::Create(cast<User>(C)->getOperand(0), A, B);
+ // And commutes, try both ways.
+ if (match(B, m_Not(m_Value(C))))
+ return SelectInst::Create(cast<User>(C)->getOperand(0), A, D);
+ }
+ // Or commutes, try both ways.
+ if (isa<SExtInst>(D) &&
+ cast<User>(D)->getOperand(0)->getType() == Type::Int1Ty) {
+ if (match(C, m_Not(m_Value(D))))
+ return SelectInst::Create(cast<User>(D)->getOperand(0), A, B);
+ // And commutes, try both ways.
+ if (match(A, m_Not(m_Value(D))))
+ return SelectInst::Create(cast<User>(D)->getOperand(0), C, B);
+ }
}
// (X >> Z) | (Y >> Z) -> (X|Y) >> Z for all shifts.