[LLVMdev] Splitting a load with 2 consumers into 2 loads.

[Triple Yang]

Hi, Joe.

I am sorry I did not catch your point. Can you provide more details?

Since SDValue/SDNode can be used multiple times, why would you want to
create two identical objects
instead of reference to the same one?

2012/12/2 Joseph Pusdesris <joe at pusdesris.com>:
> Yes, changing parameters will create a new Node, but is there some way I can
> force a new node with the same parameters?
> -Joe
>
>
> On Sat, Dec 1, 2012 at 10:57 PM, Triple Yang <triple.yang at gmail.com> wrote:
>>
>> Hi, Joseph, I guess getLoad() will either search an existed SDValue
>> *OR* create a new one for a non-existed one depending on real
>> parameters.
>>
>> Since you use exactly the same attributes dupVal/dupNode have, no
>> doubt getLoad() return the old one.
>>
>> I am not sure it's *volatile* that let you get a new result, you might
>> want to try change some other parameters and check what it turns out.
>>
>> Regards.
>>
>> 2012/12/2 Joseph Pusdesris <joe at pusdesris.com>
>> >
>> > So I think I have made some progress.
>> > SDValue dupVal  = consumer->getOperand(OpNo);
>> > LoadSDNode *dupNode = (LoadSDNode*) dupVal.getNode();
>> >
>> > SDValue newLoad = CurDAG->getLoad(dupVal.getValueType(),
>> > dupVal.getDebugLoc(),
>> >                                dupVal.getOperand(0),
>> > dupVal.getOperand(1),
>> >                                dupNode->getPointerInfo(),
>> >                                dupNode->isVolatile(),
>> > dupNode->isNonTemporal(),
>> >                                dupNode->isInvariant(),
>> > dupNode->getAlignment(),
>> >                                dupNode->getTBAAInfo(),
>> > dupNode->getRanges());
>> > However, my problem now is that it will re-use the same load still.  If
>> > I change something, like setting volatile to true for example, it will
>> > create a new node, but otherwise it will not.  Any ideas?
>> > -Joe
>> >
>> >
>> > On Fri, Nov 30, 2012 at 9:55 PM, Joseph Pusdesris <joe at pusdesris.com>
>> > wrote:
>> >>
>> >> Hi, I am writing an llvm target and I need both loads for isel reasons,
>> >> but I am struggling to find the right way.  I have been trying to use
>> >> DAG.getLoad() to make a copy, then just change the operand in the consumers,
>> >> but I cannot seem to get all of the arguments needed for that function in
>> >> order to make the copy.  Any help would be great, thanks!
>> >> -Joe
>> >
>> >
>> >
>> > _______________________________________________
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>> >
>>
>>
>>
>> --
>> 杨勇勇 (Yang Yongyong)
>
>



-- 
杨勇勇 (Yang Yongyong)