How can I write code to generate IR for: %2 = bitcast double* %1 to <2 x double>*. %3 = load <2 x double>* %2, align 16 Basically, it is similar to x86 _mm_load_pd1 intrinsics. Thanks, Zhi -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150415/66489860/attachment.html>
mats petersson
2015-Apr-15 20:03 UTC
[LLVMdev] How to do bitcast for double to <2 x double>
Create a type that is a "vector (array) of 2 double", and then a pointer to that. Now use bitcast your on double pointer to that pointer type you've created, and then create a load... If you need more help, it would help if you post the code you are working on... -- Mats On 15 April 2015 at 19:51, zhi chen <zchenhn at gmail.com> wrote:> How can I write code to generate IR for: > %2 = bitcast double* %1 to <2 x double>*. > %3 = load <2 x double>* %2, align 16 > Basically, it is similar to x86 _mm_load_pd1 intrinsics. > > Thanks, > Zhi > > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev >
What I want to do is to change the pInst from : 2%= load double* %1, align
8 to 2% = load < 2 x double>* %1, align 16, where <2 x double>
should be
two double identical double values that is same as the one in the previous
instruction
Instruction* ScalarToVectorLoad(Instruction* pInst) {
Value *loadValue = pInst->getOperand(0);
Instruction *newLoad; //this one should be 2% = load < 2 x double>* %1
BitCastInst *scalarToVector = new BitCastInst(loadValue,
VectorType::get(Type::getDoubleTy(currF->getContext()), 2),
"vectorizedLoad", pInst);
newLoad = new LoadInst(); //to be implemented...
return newLoad;
}
On Wed, Apr 15, 2015 at 1:03 PM, mats petersson <mats at
planetcatfish.com>
wrote:
> Create a type that is a "vector (array) of 2 double", and then a
> pointer to that. Now use bitcast your on double pointer to that
> pointer type you've created, and then create a load...
>
> If you need more help, it would help if you post the code you are working
> on...
>
> --
> Mats
>
> On 15 April 2015 at 19:51, zhi chen <zchenhn at gmail.com> wrote:
> > How can I write code to generate IR for:
> > %2 = bitcast double* %1 to <2 x double>*.
> > %3 = load <2 x double>* %2, align 16
> > Basically, it is similar to x86 _mm_load_pd1 intrinsics.
> >
> > Thanks,
> > Zhi
> >
> > _______________________________________________
> > LLVM Developers mailing list
> > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20150415/ca466b4e/attachment.html>