Always compute all the bits in ComputeMaskedBits.
This allows us to keep passing reduced masks to SimplifyDemandedBits, but
know about all the bits if SimplifyDemandedBits fails. This allows instcombine
to simplify cases like the one in the included testcase.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154011 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Sparc/SparcISelLowering.cpp b/lib/Target/Sparc/SparcISelLowering.cpp
index ee12633..c3e6f16 100644
--- a/lib/Target/Sparc/SparcISelLowering.cpp
+++ b/lib/Target/Sparc/SparcISelLowering.cpp
@@ -832,22 +832,19 @@
/// be zero. Op is expected to be a target specific node. Used by DAG
/// combiner.
void SparcTargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
- const APInt &Mask,
APInt &KnownZero,
APInt &KnownOne,
const SelectionDAG &DAG,
unsigned Depth) const {
APInt KnownZero2, KnownOne2;
- KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0); // Don't know anything.
+ KnownZero = KnownOne = APInt(KnownZero.getBitWidth(), 0);
switch (Op.getOpcode()) {
default: break;
case SPISD::SELECT_ICC:
case SPISD::SELECT_FCC:
- DAG.ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne,
- Depth+1);
- DAG.ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero2, KnownOne2,
- Depth+1);
+ DAG.ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1);
+ DAG.ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1);
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
diff --git a/lib/Target/Sparc/SparcISelLowering.h b/lib/Target/Sparc/SparcISelLowering.h
index f483c96..cf43048 100644
--- a/lib/Target/Sparc/SparcISelLowering.h
+++ b/lib/Target/Sparc/SparcISelLowering.h
@@ -50,7 +50,6 @@
/// in Mask are known to be either zero or one and return them in the
/// KnownZero/KnownOne bitsets.
virtual void computeMaskedBitsForTargetNode(const SDValue Op,
- const APInt &Mask,
APInt &KnownZero,
APInt &KnownOne,
const SelectionDAG &DAG,