[PATCH 7/9] math: Remove powerpc e_hypot

[Adhemerval Zanella]

On 06/10/2021 16:43, Paul E Murphy wrote:
> 
> 
> On 10/6/21 1:05 PM, Adhemerval Zanella via Libc-alpha wrote:
>> power9 master:
>>
>>    "hypot": {
>>     "workload-random": {
>>      "duration": 5.20744e+08,
>>      "iterations": 5.6e+07,
>>      "reciprocal-throughput": 9.27604,
>>      "latency": 9.32194,
>>      "max-throughput": 1.07805e+08,
>>      "min-throughput": 1.07274e+08
>>     }
>>    }
>>
>> power9 patched:
>>
>>    "hypot": {
>>     "workload-random": {
>>      "duration": 5.23124e+08,
>>      "iterations": 5.4e+07,
>>      "reciprocal-throughput": 9.51892,
>>      "latency": 9.85606,
>>      "max-throughput": 1.05054e+08,
>>      "min-throughput": 1.0146e+08
>>     }
>>    }
>>
>> power8 master:
>>
>>    "hypot": {
>>     "workload-random": {
>>      "duration": 5.21128e+08,
>>      "iterations": 4.6e+07,
>>      "reciprocal-throughput": 11.3589,
>>      "latency": 11.2988,
>>      "max-throughput": 8.80368e+07,
>>      "min-throughput": 8.85047e+07
>>     }
>>    }
>>
>> power8 patched:
>>
>>    "hypot": {
>>     "workload-random": {
>>      "duration": 5.22651e+08,
>>      "iterations": 4.6e+07,
>>      "reciprocal-throughput": 11.3764,
>>      "latency": 11.3475,
>>      "max-throughput": 8.79009e+07,
>>      "min-throughput": 8.81252e+07
>>     }
>>    }
>>
>> Checked on powerpc64-linux-gnu (power8) and powerpc64le-linux-gnu
>> (power9).
>> ---
>>   sysdeps/powerpc/fpu/e_hypot.c                 | 87 -------------------
>>   sysdeps/powerpc/fpu/e_hypotf.c                | 78 -----------------
>>   .../powerpc32/power4/fpu/multiarch/Makefile   |  5 +-
>>   .../power4/fpu/multiarch/e_hypot-power7.c     | 23 -----
>>   .../power4/fpu/multiarch/e_hypot-ppc32.c      | 23 -----
>>   .../powerpc32/power4/fpu/multiarch/e_hypot.c  | 33 -------
>>   .../power4/fpu/multiarch/e_hypotf-power7.c    | 23 -----
>>   .../power4/fpu/multiarch/e_hypotf-ppc32.c     | 23 -----
>>   .../powerpc32/power4/fpu/multiarch/e_hypotf.c | 33 -------
>>   9 files changed, 1 insertion(+), 327 deletions(-)
>>   delete mode 100644 sysdeps/powerpc/fpu/e_hypot.c
>>   delete mode 100644 sysdeps/powerpc/fpu/e_hypotf.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypot-power7.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypot-ppc32.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypot.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypotf-power7.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypotf-ppc32.c
>>   delete mode 100644 sysdeps/powerpc/powerpc32/power4/fpu/multiarch/e_hypotf.c
> 
> This also removes the ppc specific hypotf too. Have you had a chance to measure the difference?
> 
> I think it is OK if the performance difference is negligible. Though, I don't speak for the other ppc contributors in that regard. They may want to double-check the results.

I would expect the performance difference to be similar to 64-bit,
at least on the hardware I checked (since most of the time would
be spent in FPU calculations).

In any case, I don't see much gain in keeping a 32-bit powerpc
implementation that deviates from generic implementation.