[PATCH] Add a target legalize hook for SplitVectorOperand

[Eli Friedman]

On Mon, Jul 22, 2013 at 6:20 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
> On Mon, Jul 22, 2013 at 6:03 PM, Justin Holewinski
> <justin.holewinski at gmail.com> wrote:
>> To be more specific, the X86 target declares that v2i64 extract_vector_elt
>> needs to be custom lowered:
>>
>>     if (Subtarget->is64Bit()) {
>>       setOperationAction(ISD::INSERT_VECTOR_ELT,  MVT::v2i64, Custom);
>>       setOperationAction(ISD::EXTRACT_VECTOR_ELT, MVT::v2i64, Custom);
>>     }
>>
>> But if the element type is i64 and the index is constant, then its lowered
>> to itself:
>>
>>   if (VT == MVT::i32 || VT == MVT::i64) {
>>     // ExtractPS/pextrq works with constant index.
>>     if (isa<ConstantSDNode>(Op.getOperand(1)))
>>       return Op;
>>   }
>
> If you don't mind fixing it, the condition should be "VT == MVT::i32
> || (Subtarget->is64Bit() && VT == MVT::i64))".  Same idea applies to
> LowerINSERT_VECTOR_ELT_SSE4.

Err, wait, what am I thinking. Nevermind, I'll have to think about it
a bit more.

-Eli