unsigned NumInScalars = N->getNumOperands();
DebugLoc dl = N->getDebugLoc();
EVT VT = N->getValueType(0);
+
+ // A vector built entirely of undefs is undef.
+ if (ISD::allOperandsUndef(N))
+ return DAG.getUNDEF(VT);
+
// Check to see if this is a BUILD_VECTOR of a bunch of values
// which come from any_extend or zero_extend nodes. If so, we can create
// a new BUILD_VECTOR using bit-casts which may enable other BUILD_VECTOR
// using shuffles.
EVT SourceType = MVT::Other;
bool AllAnyExt = true;
- bool AllUndef = true;
+
for (unsigned i = 0; i != NumInScalars; ++i) {
SDValue In = N->getOperand(i);
// Ignore undef inputs.
if (In.getOpcode() == ISD::UNDEF) continue;
- AllUndef = false;
bool AnyExt = In.getOpcode() == ISD::ANY_EXTEND;
bool ZeroExt = In.getOpcode() == ISD::ZERO_EXTEND;
AllAnyExt &= AnyExt;
}
- if (AllUndef)
- return DAG.getUNDEF(VT);
-
// In order to have valid types, all of the inputs must be extended from the
// same source type and all of the inputs must be any or zero extend.
// Scalar sizes must be a power of two.
return N->getOperand(0);
// Check if all of the operands are undefs.
- bool AllUndef = true;
- for (unsigned i = 0; i < N->getNumOperands(); ++i)
- if (N->getOperand(i).getOpcode() != ISD::UNDEF) {
- AllUndef = false;
- break;
- }
-
- if (AllUndef)
+ if (ISD::allOperandsUndef(N))
return DAG.getUNDEF(N->getValueType(0));
return SDValue();