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>