[llvm-commits] [llvm] r137114 - in /llvm/trunk: lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/avx-cvt.ll

[Bruno Cardoso Lopes]

I was thinking about that too. Just found a much better solution! Thanks Eli!

On Mon, Aug 8, 2011 at 10:55 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
> On Mon, Aug 8, 2011 at 10:48 PM, Bruno Cardoso Lopes
> <bruno.cardoso at gmail.com> wrote:
>> Author: bruno
>> Date: Tue Aug  9 00:48:01 2011
>> New Revision: 137114
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=137114&view=rev
>> Log:
>> Handle sitofp between v4f64 <- v4i32. Fix PR10559
>>
>> Modified:
>>    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
>>    llvm/trunk/test/CodeGen/X86/avx-cvt.ll
>>
>> Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=137114&r1=137113&r2=137114&view=diff
>> ==============================================================================
>> --- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
>> +++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Tue Aug  9 00:48:01 2011
>> @@ -969,6 +969,9 @@
>>     setOperationAction(ISD::SINT_TO_FP,         MVT::v8i32, Legal);
>>     setOperationAction(ISD::FP_ROUND,           MVT::v4f32, Legal);
>>
>> +    // sint_to_fp between different vector types needs custom handling
>> +    setOperationAction(ISD::SINT_TO_FP,         MVT::v4i32, Custom);
>> +
>>     setOperationAction(ISD::CONCAT_VECTORS,     MVT::v4f64,  Custom);
>>     setOperationAction(ISD::CONCAT_VECTORS,     MVT::v4i64,  Custom);
>>     setOperationAction(ISD::CONCAT_VECTORS,     MVT::v8f32,  Custom);
>> @@ -7078,6 +7081,24 @@
>>  SDValue X86TargetLowering::LowerSINT_TO_FP(SDValue Op,
>>                                            SelectionDAG &DAG) const {
>>   EVT SrcVT = Op.getOperand(0).getValueType();
>> +  EVT DstVT = Op.getValueType();
>> +  DebugLoc dl = Op.getDebugLoc();
>> +
>> +  if (SrcVT.isVector() && DstVT.isVector()) {
>> +    unsigned SrcVTSize = SrcVT.getSizeInBits();
>> +    unsigned DstVTSize = DstVT.getSizeInBits();
>> +
>> +    // Support directly by the target
>> +    if (SrcVTSize == DstVTSize)
>> +      return Op;
>> +
>> +    // Handle v4f64 = sitofp v4i32
>> +    if (DstVT != MVT::v4f64 && SrcVT != MVT::v4i32)
>> +      return SDValue();
>> +
>> +    SDValue V = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::v4f32, Op.getOperand(0));
>> +    return DAG.getNode(ISD::FP_EXTEND, dl, DstVT, V);
>> +  }
>
> Aren't there accuracy issues with this approach?  A float can't
> precisely represent every possible i32.
>
> -Eli
>



-- 
Bruno Cardoso Lopes
http://www.brunocardoso.cc