This is the mail archive of the libc-alpha@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: RFC: What inputs to use for sqrt perf testing


On 10/03/2013 10:39 PM, Siddhesh Poyarekar wrote:
> On 4 October 2013 02:55, Steve Ellcey <sellcey@mips.com> wrote:
>>
>> While making a sqrt performance improvement for MIPS I noticed that there
>> was no sqrt performance test in the 'make bench' tests and Joseph suggested
>> that we should have one.  It looks like adding it is trivial (see patch),
>> but the real question is what input to use.  I just threw in 1.9 and 10000.0
>> to test this patch, but I don't think those are necessarily good choices.
>>
>> Are there any math experts out there could suggest a better selection of
>> inputs for sqrt to use in the performance tests?
>>
>> Here is my strawman patch, I don't expect this to get checked in as it
>> is, I am just including it for reference purposes.
> 
> The method I'm using for this is to add probes at various branch
> points within the function and use a systemtap script to print out the
> input whenever the probe point is hit.  This is a bit slow (in terms
> of effort), but would ensure good coverage.  Also, as a starting
> point, I wouldn't mind having your strawman patch in and then more
> inputs added to it when you have them ready.

Would it make sense to start off with all the inputs used by
libm-test.inc e.g. sqrt_test_data?

Cheers,
Carlos.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]