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Triple Yang

2012-Dec-02 03:57 UTC

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

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
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>


--
杨勇勇 (Yang Yongyong)

Joseph Pusdesris

2012-Dec-02 04:01 UTC

head link

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

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
> >
> >
> >
> > _______________________________________________
> > LLVM Developers mailing list
> > LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> >
>
>
>
> --
> 杨勇勇 (Yang Yongyong)
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Triple Yang

2012-Dec-02 04:44 UTC

head link

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

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
>> >
>> >
>> >
>> > _______________________________________________
>> > LLVM Developers mailing list
>> > LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>> > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>> >
>>
>>
>>
>> --
>> 杨勇勇 (Yang Yongyong)
>
>


-- 
杨勇勇 (Yang Yongyong)

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