llvm dev - Aug 2013 - [LLVMdev] ctlz pattern

Does anyone know some simple c/c++ code or .ll code which will cause 
this ctlz pattern to be emitted?

Tia.

Reed

Are you looking for something other than calling __builtin_clz from c++ or
calling @llvm.ctlz.* instrinsic from IR?

I don't think we have anything that will auto converting a loop to ctlz or
anything like that. We only seem to have a detection for popcount loops.


On Thu, Aug 15, 2013 at 9:01 PM, reed kotler <rkotler at mips.com> wrote:
> Does anyone know some simple c/c++ code or .ll code which will cause this
> ctlz pattern to be emitted?
>
> Tia.
>
> Reed
>
>
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-- 
~Craig
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On 08/15/2013 09:13 PM, Craig Topper wrote:
> Are you looking for something other than calling __builtin_clz from 
> c++ or calling @llvm.ctlz.* instrinsic from IR?
>
That's good enough. Thanks.

On Mips16 I don't have an instruction for that so I think I need to ask 
that it be expanded,
so I will try that tomorrow but I will need a small test case to put it 
back.

> I don't think we have anything that will auto converting a loop to 
> ctlz or anything like that. We only seem to have a detection for 
> popcount loops.
>
>
> On Thu, Aug 15, 2013 at 9:01 PM, reed kotler <rkotler at mips.com 
> <mailto:rkotler at mips.com>> wrote:
>
>     Does anyone know some simple c/c++ code or .ll code which will
>     cause this ctlz pattern to be emitted?
>
>     Tia.
>
>     Reed
>
>
>     _______________________________________________
>     LLVM Developers mailing list
>     LLVMdev at cs.uiuc.edu <mailto:LLVMdev at cs.uiuc.edu>
>     http://llvm.cs.uiuc.edu
>     http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
>
>
>
> -- 
> ~Craig
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