[llvm-commits] [llvm] r94990 - in /llvm/trunk/lib/CodeGen/SelectionDAG: DAGCombiner.cpp SelectionDAG.cpp

[Mon Ping Wang]

Hi Duncan,

On Feb 1, 2010, at 11:20 AM, Duncan Sands wrote:
> 
>> -   if (InOp.getValueType() != EltVT)
>> -     return DAG.getNode(ISD::TRUNCATE, InVec.getDebugLoc(), EltVT, InOp);
>> +   EVT NVT = N->getValueType(0);
>> +   if (InOp.getValueType() != NVT) {
>> +     assert(InOp.getValueType().isInteger() && NVT.isInteger());
>> +     if (NVT.getSizeInBits() > InOp.getValueType().getSizeInBits())
>> +       return DAG.getNode(ISD::SIGN_EXTEND, InVec.getDebugLoc(), NVT, InOp);
>> +     else
>> +       return DAG.getNode(ISD::TRUNCATE, InVec.getDebugLoc(), NVT, InOp);
>> +   }
> 
> There is a special method for this: DAG.getSExtOrTrunc.

Fixed.

> 
>> @@ -2765,7 +2765,7 @@
>>     // operations are lowered to scalars.
>>     if (N1.getOpcode() == ISD::INSERT_VECTOR_ELT) {
>>       // If the indices are the same, return the inserted element.
>> -      if (N1.getOperand(2) == N2)
>> +      if (N1.getOperand(2) == N2 && VT == N1.getOperand(1).getValueType())
>>         return N1.getOperand(1);
>>       // If the indices are known different, extract the element from
>>       // the original vector.
> 
> Why not just extend/truncate here too?
> 

Fixed.

Thanks,
  -- Mon Ping