PING^5 [PATCH 0/9] rs6000: Rework rs6000_emit_vector_compare

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi,

Gentle ping this series:

https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607146.html

BR,
Kewen

>>>> on 2022/11/24 17:15, Kewen Lin wrote:
>>>>> Hi,
>>>>>
>>>>> Following Segher's suggestion, this patch series is to rework
>>>>> function rs6000_emit_vector_compare for vector float and int
>>>>> in multiple steps, it's based on the previous attempts [1][2].
>>>>> As mentioned in [1], the need to rework this for float is to
>>>>> make a centralized place for vector float comparison handlings
>>>>> instead of supporting with swapping ops and reversing code etc.
>>>>> dispersedly.  It's also for a subsequent patch to handle
>>>>> comparison operators with or without trapping math (PR105480).
>>>>> With the handling on vector float reworked, we can further make
>>>>> the handling on vector int simplified as shown.
>>>>>
>>>>> For Segher's concern about whether this rework causes any
>>>>> assembly change, I constructed two testcases for vector float[3]
>>>>> and int[4] respectively before, it showed the most are fine
>>>>> excepting for the difference on LE and UNGT, it's demonstrated
>>>>> as improvement since it uses GE instead of GT ior EQ.  The
>>>>> associated test case in patch 3/9 is a good example.
>>>>>
>>>>> Besides, w/ and w/o the whole patch series, I built the whole
>>>>> SPEC2017 at options -O3 and -Ofast separately, checked the
>>>>> differences on object assembly.  The result showed that the
>>>>> most are unchanged, except for:
>>>>>
>>>>>   * at -O3, 521.wrf_r has 9 object files and 526.blender_r has
>>>>>     9 object files with differences.
>>>>>
>>>>>   * at -Ofast, 521.wrf_r has 12 object files, 526.blender_r has
>>>>>     one and 527.cam4_r has 4 object files with differences.
>>>>>
>>>>> By looking into these differences, all significant differences
>>>>> are caused by the known improvement mentined above transforming
>>>>> GT ior EQ to GE, which can also affect unrolling decision due
>>>>> to insn count.  Some other trivial differences are branch
>>>>> target offset difference, nop difference for alignment, vsx
>>>>> register number differences etc.
>>>>>
>>>>> I also evaluated the runtime performance for these changed
>>>>> benchmarks, the result is neutral.
>>>>>
>>>>> These patches are bootstrapped and regress-tested
>>>>> incrementally on powerpc64-linux-gnu P7 & P8, and
>>>>> powerpc64le-linux-gnu P9 & P10.
>>>>>
>>>>> Is it ok for trunk?
>>>>>
>>>>> BR,
>>>>> Kewen
>>>>> -----
>>>>> [1] https://gcc.gnu.org/pipermail/gcc-patches/2022-November/606375.html
>>>>> [2] https://gcc.gnu.org/pipermail/gcc-patches/2022-November/606376.html
>>>>> [3] https://gcc.gnu.org/pipermail/gcc-patches/2022-November/606504.html
>>>>> [4] https://gcc.gnu.org/pipermail/gcc-patches/2022-November/606506.html
>>>>>
>>>>> Kewen Lin (9):
>>>>>   rs6000: Rework vector float comparison in rs6000_emit_vector_compare - p1
>>>>>   rs6000: Rework vector float comparison in rs6000_emit_vector_compare - p2
>>>>>   rs6000: Rework vector float comparison in rs6000_emit_vector_compare - p3
>>>>>   rs6000: Rework vector float comparison in rs6000_emit_vector_compare - p4
>>>>>   rs6000: Rework vector integer comparison in rs6000_emit_vector_compare - p1
>>>>>   rs6000: Rework vector integer comparison in rs6000_emit_vector_compare - p2
>>>>>   rs6000: Rework vector integer comparison in rs6000_emit_vector_compare - p3
>>>>>   rs6000: Rework vector integer comparison in rs6000_emit_vector_compare - p4
>>>>>   rs6000: Rework vector integer comparison in rs6000_emit_vector_compare - p5
>>>>>
>>>>>  gcc/config/rs6000/rs6000.cc                 | 180 ++++++--------------
>>>>>  gcc/testsuite/gcc.target/powerpc/vcond-fp.c |  25 +++
>>>>>  2 files changed, 74 insertions(+), 131 deletions(-)
>>>>>  create mode 100644 gcc/testsuite/gcc.target/powerpc/vcond-fp.c
>>>>>