qemu/target/ppc/translate
Lucas Mateus Castro (alqotel) bbd8dd5e45 target/ppc: Use gvec to decode XVTSTDC[DS]P
Used gvec to translate XVTSTDCSP and XVTSTDCDP.

xvtstdcsp:
rept    loop    imm     master version  prev version        current version
25      4000    0       0,206200        0,040730 (-80.2%)    0,040740 (-80.2%)
25      4000    1       0,205120        0,053650 (-73.8%)    0,053510 (-73.9%)
25      4000    3       0,206160        0,058630 (-71.6%)    0,058570 (-71.6%)
25      4000    51      0,217110        0,191490 (-11.8%)    0,192320 (-11.4%)
25      4000    127     0,206160        0,191490 (-7.1%)     0,192640 (-6.6%)
8000    12      0       1,234719        0,418833 (-66.1%)    0,386365 (-68.7%)
8000    12      1       1,232417        1,435979 (+16.5%)    1,462792 (+18.7%)
8000    12      3       1,232760        1,766073 (+43.3%)    1,743990 (+41.5%)
8000    12      51      1,239281        1,319562 (+6.5%)     1,423479 (+14.9%)
8000    12      127     1,231708        1,315760 (+6.8%)     1,426667 (+15.8%)

xvtstdcdp:
rept    loop    imm     master version  prev version    current version
25      4000    0       0,159930        0,040830 (-74.5%)    0,040610 (-74.6%)
25      4000    1       0,160640        0,053670 (-66.6%)    0,053480 (-66.7%)
25      4000    3       0,160020        0,063030 (-60.6%)    0,062960 (-60.7%)
25      4000    51      0,160410        0,128620 (-19.8%)    0,127470 (-20.5%)
25      4000    127     0,160330        0,127670 (-20.4%)    0,128690 (-19.7%)
8000    12      0       1,190365        0,422146 (-64.5%)    0,388417 (-67.4%)
8000    12      1       1,191292        1,445312 (+21.3%)    1,428698 (+19.9%)
8000    12      3       1,188687        1,980656 (+66.6%)    1,975354 (+66.2%)
8000    12      51      1,191250        1,264500 (+6.1%)     1,355083 (+13.8%)
8000    12      127     1,197313        1,266729 (+5.8%)     1,349156 (+12.7%)

Overall, these instructions are the hardest ones to measure performance
as the gvec implementation is affected by the immediate. Above there are
5 different scenarios when it comes to immediate and 2 when it comes to
rept/loop combination. The immediates scenarios are: all bits are 0
therefore the target register should just be changed to 0, with 1 bit
set, with 2 bits set in a combination the new implementation can deal
with using gvec, 4 bits set and the new implementation can't deal with
it using gvec and all bits set. The rept/loop scenarios are high loop
and low rept (so it should spend more time executing it than translating
it) and high rept low loop (so it should spend more time translating it
than executing this code).
These comparisons are between the upstream version, a previous similar
implementation and a one with a cleaner code(this one).
For a comparison with o previous different implementation:
<20221010191356.83659-13-lucas.araujo@eldorado.org.br>

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221019125040.48028-13-lucas.araujo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2022-10-28 13:15:22 -03:00
..
branch-impl.c.inc PPC64/TCG: Implement 'rfebb' instruction 2021-12-17 17:57:19 +01:00
dfp-impl.c.inc target/ppc: Move ddedpd[q],denbcd[q],dscli[q],dscri[q] to decodetree 2021-11-09 10:32:52 +11:00
fixedpoint-impl.c.inc target/ppc: Implement hashstp and hashchkp 2022-09-20 10:54:06 -03:00
fp-impl.c.inc target/ppc: Merge fsqrt and fsqrts helpers 2022-09-20 10:54:06 -03:00
fp-ops.c.inc target/ppc: Move fsqrts to decodetree 2022-09-20 10:54:06 -03:00
processor-ctrl-impl.c.inc target/ppc: move msgsync to decodetree 2022-10-28 13:15:21 -03:00
spe-impl.c.inc ppc patch queue 2020-08-18 2020-08-24 09:35:21 +01:00
spe-ops.c.inc meson: rename included C source files to .c.inc 2020-08-21 06:18:30 -04:00
storage-ctrl-impl.c.inc target/ppc: Implement slbiag 2022-07-18 13:59:43 -03:00
vmx-impl.c.inc target/ppc: Move VABSDU[BHW] to decodetree and use gvec 2022-10-28 13:15:22 -03:00
vmx-ops.c.inc target/ppc: Move VABSDU[BHW] to decodetree and use gvec 2022-10-28 13:15:22 -03:00
vsx-impl.c.inc target/ppc: Use gvec to decode XVTSTDC[DS]P 2022-10-28 13:15:22 -03:00
vsx-ops.c.inc target/ppc: Moved XSTSTDC[QDS]P to decodetree 2022-10-28 13:15:22 -03:00