PatternMatch: Introduce a matcher for instructions with the "exact" bit. Use it to simplify a few matchers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147403 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index b9a48ea..6de4426 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -811,11 +811,9 @@
// An exact divide or right shift can only shift off zero bits, so the result
// is a power of two only if the first operand is a power of two and not
// copying a sign bit (sdiv int_min, 2).
- if (match(V, m_LShr(m_Value(), m_Value())) ||
- match(V, m_UDiv(m_Value(), m_Value()))) {
- PossiblyExactOperator *PEO = cast<PossiblyExactOperator>(V);
- if (PEO->isExact())
- return isPowerOfTwo(PEO->getOperand(0), TD, OrZero, Depth);
+ if (match(V, m_Exact(m_LShr(m_Value(), m_Value()))) ||
+ match(V, m_Exact(m_UDiv(m_Value(), m_Value())))) {
+ return isPowerOfTwo(cast<Operator>(V)->getOperand(0), TD, OrZero, Depth);
}
return false;
@@ -879,10 +877,8 @@
return true;
}
// div exact can only produce a zero if the dividend is zero.
- else if (match(V, m_IDiv(m_Value(X), m_Value()))) {
- PossiblyExactOperator *BO = cast<PossiblyExactOperator>(V);
- if (BO->isExact())
- return isKnownNonZero(X, TD, Depth);
+ else if (match(V, m_Exact(m_IDiv(m_Value(X), m_Value())))) {
+ return isKnownNonZero(X, TD, Depth);
}
// X + Y.
else if (match(V, m_Add(m_Value(X), m_Value(Y)))) {