[LLVMdev] Simple NEON optimization

[Bob Wilson]

On Nov 12, 2010, at 10:47 AM, Evan Cheng wrote:

> Is this related to Owen's patch r118453?

Oh, yes, it is indeed.  I had forgotten about that already.  Renato, this ought to be working already.  Maybe you have an older version?

> 
> Evan
> 
> On Nov 12, 2010, at 10:42 AM, Renato Golin wrote:
> 
>> On 12 November 2010 17:52, Bob Wilson <bob.wilson at apple.com> wrote:
>>> I recommend implementing this as a target-specific DAG combine optimization.  We already have target-specific DAG nodes for the relevant NEON comparison operations (ARMISD::VCEQ, etc. -- see ARMISelLowering.h) as well as the vmov (ARMISD::VMOVIMM).  You just need to teach the DAG combiner how to fold them together.  Here's what you need to do (all of this code is in ARMISelLowering.cpp):
>> 
>> Hi Bob,
>> 
>> I thought so... I'll get cracked and see if I can generate some simple tests.
>> 
>> Thank you very much for the detailed explanation!
>> 
>> cheers,
>> --renato
>> 
>> _______________________________________________
>> LLVM Developers mailing list
>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>