[InstSimplify] refactor 'or' logic folds; NFC
Reduce duplication for handling the top-level commuted operands.
There are several other folds that should be moved in here, but
we need to make sure there's good test coverage.
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index cab3455..8f1ba83 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -2180,6 +2180,25 @@
return ::SimplifyAndInst(Op0, Op1, Q, RecursionLimit);
}
+static Value *simplifyOrLogic(Value *X, Value *Y) {
+ assert(X->getType() == Y->getType() && "Expected same type for 'or' ops");
+ Type *Ty = X->getType();
+
+ // X | ~X --> -1
+ if (match(Y, m_Not(m_Specific(X))))
+ return ConstantInt::getAllOnesValue(Ty);
+
+ // X | ~(X & ?) = -1
+ if (match(Y, m_Not(m_c_And(m_Specific(X), m_Value()))))
+ return ConstantInt::getAllOnesValue(Ty);
+
+ // X | (X & ?) --> X
+ if (match(Y, m_c_And(m_Specific(X), m_Value())))
+ return X;
+
+ return nullptr;
+}
+
/// Given operands for an Or, see if we can fold the result.
/// If not, this returns null.
static Value *SimplifyOrInst(Value *Op0, Value *Op1, const SimplifyQuery &Q,
@@ -2202,26 +2221,10 @@
if (Op0 == Op1 || match(Op1, m_Zero()))
return Op0;
- // A | ~A = ~A | A = -1
- if (match(Op0, m_Not(m_Specific(Op1))) ||
- match(Op1, m_Not(m_Specific(Op0))))
- return Constant::getAllOnesValue(Op0->getType());
-
- // (A & ?) | A = A
- if (match(Op0, m_c_And(m_Specific(Op1), m_Value())))
- return Op1;
-
- // A | (A & ?) = A
- if (match(Op1, m_c_And(m_Specific(Op0), m_Value())))
- return Op0;
-
- // ~(A & ?) | A = -1
- if (match(Op0, m_Not(m_c_And(m_Specific(Op1), m_Value()))))
- return Constant::getAllOnesValue(Op1->getType());
-
- // A | ~(A & ?) = -1
- if (match(Op1, m_Not(m_c_And(m_Specific(Op0), m_Value()))))
- return Constant::getAllOnesValue(Op0->getType());
+ if (Value *R = simplifyOrLogic(Op0, Op1))
+ return R;
+ if (Value *R = simplifyOrLogic(Op1, Op0))
+ return R;
if (Value *V = simplifyLogicOfAddSub(Op0, Op1, Instruction::Or))
return V;
