/// bytes of each element [124] -> [bhw].
SDOperand PPC::get_VSPLI_elt(SDNode *N, unsigned ByteSize, SelectionDAG &DAG) {
SDOperand OpVal(0, 0);
+
+ // If ByteSize of the splat is bigger than the element size of the
+ // build_vector, then we have a case where we are checking for a splat where
+ // multiple elements of the buildvector are folded together into a single
+ // logical element of the splat (e.g. "vsplish 1" to splat {0,1}*8).
+ unsigned EltSize = 16/N->getNumOperands();
+ if (EltSize < ByteSize) {
+ unsigned Multiple = ByteSize/EltSize; // Number of BV entries per spltval.
+ SDOperand UniquedVals[4];
+ assert(Multiple > 1 && Multiple <= 4 && "How can this happen?");
+
+ // See if all of the elements in the buildvector agree across.
+ for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
+ if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;
+ // If the element isn't a constant, bail fully out.
+ if (!isa<ConstantSDNode>(N->getOperand(i))) return SDOperand();
+
+
+ if (UniquedVals[i&(Multiple-1)].Val == 0)
+ UniquedVals[i&(Multiple-1)] = N->getOperand(i);
+ else if (UniquedVals[i&(Multiple-1)] != N->getOperand(i))
+ return SDOperand(); // no match.
+ }
+
+ // Okay, if we reached this point, UniquedVals[0..Multiple-1] contains
+ // either constant or undef values that are identical for each chunk. See
+ // if these chunks can form into a larger vspltis*.
+
+ // Check to see if all of the leading entries are either 0 or -1. If
+ // neither, then this won't fit into the immediate field.
+ bool LeadingZero = true;
+ bool LeadingOnes = true;
+ for (unsigned i = 0; i != Multiple-1; ++i) {
+ if (UniquedVals[i].Val == 0) continue; // Must have been undefs.
+
+ LeadingZero &= cast<ConstantSDNode>(UniquedVals[i])->isNullValue();
+ LeadingOnes &= cast<ConstantSDNode>(UniquedVals[i])->isAllOnesValue();
+ }
+ // Finally, check the least significant entry.
+ if (LeadingZero) {
+ if (UniquedVals[Multiple-1].Val == 0)
+ return DAG.getTargetConstant(0, MVT::i32); // 0,0,0,undef
+ int Val = cast<ConstantSDNode>(UniquedVals[Multiple-1])->getValue();
+ if (Val < 16)
+ return DAG.getTargetConstant(Val, MVT::i32); // 0,0,0,4 -> vspltisw(4)
+ }
+ if (LeadingOnes) {
+ if (UniquedVals[Multiple-1].Val == 0)
+ return DAG.getTargetConstant(~0U, MVT::i32); // -1,-1,-1,undef
+ int Val =cast<ConstantSDNode>(UniquedVals[Multiple-1])->getSignExtended();
+ if (Val >= -16) // -1,-1,-1,-2 -> vspltisw(-2)
+ return DAG.getTargetConstant(Val, MVT::i32);
+ }
+
+ return SDOperand();
+ }
+
// Check to see if this buildvec has a single non-undef value in its elements.
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;