fold noop vbitconvert instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35943 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2007-04-12 05:58:43 +00:00
parent 1780d861ac
commit 4829b1c6ab

View File

@ -1484,6 +1484,15 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,
MVT::getVectorNumElements(VT) == N3.getNumOperands() &&
"Illegal VECTOR_SHUFFLE node!");
break;
case ISD::VBIT_CONVERT:
// Fold vbit_convert nodes from a type to themselves.
if (N1.getValueType() == MVT::Vector) {
assert(isa<ConstantSDNode>(*(N1.Val->op_end()-2)) &&
isa<VTSDNode>(*(N1.Val->op_end()-1)) && "Malformed vector input!");
if (*(N1.Val->op_end()-2) == N2 && *(N1.Val->op_end()-1) == N3)
return N1;
}
break;
}
// Memoize node if it doesn't produce a flag.