[llvm-commits] [llvm] r143177 - in /llvm/trunk: lib/CodeGen/SelectionDAG/ lib/Target/ARM/ lib/Target/X86/ lib/Target/XCore/ test/CodeGen/CellSPU/ test/CodeGen/Mips/ test/CodeGen/Thumb/ test/CodeGen/X86/

[Dan Gohman]

On Oct 27, 2011, at 6:56 PM, Eli Friedman wrote:

> On Thu, Oct 27, 2011 at 6:29 PM, Dan Gohman <gohman at apple.com> wrote:
>> @@ -3628,6 +3351,35 @@
>>     Results.push_back(Tmp1);
>>     break;
>>   }
>> +  case ISD::BUILD_VECTOR:
>> +    Results.push_back(ExpandBUILD_VECTOR(Node));
>> +    break;
>> +  case ISD::SRA:
>> +  case ISD::SRL:
>> +  case ISD::SHL: {
>> +    // Scalarize vector SRA/SRL/SHL.
>> +    EVT VT = Node->getValueType(0);
>> +    assert(VT.isVector() && "Unable to legalize non-vector shift");
>> +    assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
>> +    unsigned NumElem = VT.getVectorNumElements();
>> +
>> +    SmallVector<SDValue, 8> Scalars;
>> +    for (unsigned Idx = 0; Idx < NumElem; Idx++) {
>> +      SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
>> +                               VT.getScalarType(),
>> +                               Node->getOperand(0), DAG.getIntPtrConstant(Idx));
>> +      SDValue Sh = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
>> +                               VT.getScalarType(),
>> +                               Node->getOperand(1), DAG.getIntPtrConstant(Idx));
>> +      Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
>> +                                    VT.getScalarType(), Ex, Sh));
>> +    }
>> +    SDValue Result =
>> +      DAG.getNode(ISD::BUILD_VECTOR, dl, Node->getValueType(0),
>> +                  &Scalars[0], Scalars.size());
>> +    DAG.ReplaceAllUsesWith(SDValue(Node, 0), Result, this);
>> +    break;
>> +  }
> 
> We ought to be scalarizing vector shifts in LegalizeVectorOps; is
> there some case where that is not sufficient?

That code predates this patch. It may be a leftover from pre-LegalizeTypes days.

Dan