aboutsummaryrefslogtreecommitdiff
path: root/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
-rw-r--r--lib/CodeGen/SelectionDAG/SelectionDAG.cpp15
1 files changed, 9 insertions, 6 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index a12ff10c33..2f3bfcfb73 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1133,16 +1133,19 @@ SDOperand SelectionDAG::FoldSetCC(MVT::ValueType VT, SDOperand N1,
return SDOperand();
}
+/// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
+/// use this predicate to simplify operations downstream.
+bool SelectionDAG::SignBitIsZero(SDOperand Op, unsigned Depth) const {
+ unsigned BitWidth = Op.getValueSizeInBits();
+ return MaskedValueIsZero(Op, APInt::getSignBit(BitWidth), Depth);
+}
+
/// MaskedValueIsZero - Return true if 'V & Mask' is known to be zero. We use
/// this predicate to simplify operations downstream. Mask is known to be zero
/// for bits that V cannot have.
-bool SelectionDAG::MaskedValueIsZero(SDOperand Op, uint64_t Mask,
+bool SelectionDAG::MaskedValueIsZero(SDOperand Op, const APInt &Mask,
unsigned Depth) const {
- // The masks are not wide enough to represent this type! Should use APInt.
- if (Op.getValueType() == MVT::i128)
- return false;
-
- uint64_t KnownZero, KnownOne;
+ APInt KnownZero, KnownOne;
ComputeMaskedBits(Op, Mask, KnownZero, KnownOne, Depth);
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
return (KnownZero & Mask) == Mask;