[PATCH] PPC64 Use hardware sqrt.

[Tom Gall]

Kumar Gala wrote:

> Understand, but future PPC64 from Freescale (former Motorola SPS) are 
> unlikely to implement it.

If they do then likely they will also leave the other optional floating 
point operations unimplemented and in that case the correct way to build 
glibc is with the --nf option which is already the case for PPC32 
processors without floating point. If the processor has all the other 
optional floating point instructions except sqrt, then I'd say that 
design needs to be revisited. Historically the optional floating point 
instructions are either all there (as is the case with ALL ppc64 
processors ever made) or not in which case as pointed out to you the 
--nf option is for you.

I believe sjmunroe is right and his implementation is sound.  

Regards,

Tom

> - kumar
>
> On Apr 30, 2004, at 11:00 AM, Steve Munroe wrote:
>
>> Kumar Gala wrote on 04/29/2004 05:55:21 PM:
>>
>>> I do not think its fair to say that all future PPC64 processors will
>>> implement the fsqrt instruction.
>>>
>>> - kumar
>>>
>>
>> All server (i/pSeries) and 970 models do and will. The silicon required
>> for this is so small as to be lost in the noise of a modern chip design.
>>
>> So I will take 3-5X performance gain.
>>
>> Steven J. Munroe
>> Linux on Power Toolchain Architect
>> IBM Corporation, Linux Technology Center
>