47 Commits

Author SHA1 Message Date
go101
44b54b99c9 strings,bytes: improve Repeat panic messages
The Repeat("-", maxInt) call should produce

   panic: runtime error: makeslice: len out of range

instead of

   panic: strings: Repeat output length overflow

This PR is only for theory perfection.

Change-Id: If67d87b147d666fbbb7238656f2a0cb6cf1dbb5b
GitHub-Last-Rev: 29dc0cb9c9c63d8a008960b4527d6aa6798c1c17
GitHub-Pull-Request: golang/go#67068
Reviewed-on: https://go-review.googlesource.com/c/go/+/581936
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2024-05-03 12:58:37 +00:00
Mauri de Souza Meneguzzo
66b776b025 runtime: short path for equal pointers in arm64 memequal
If memequal is invoked with the same pointers as arguments it ends up
comparing the whole memory contents, instead of just comparing the pointers.

This effectively makes an operation that could be O(1) into O(n). All the
other architectures already have this optimization in place. For
instance, arm64 also have it, in memequal_varlen.

Such optimization is very specific, one case that it will probably benefit is
programs that rely heavily on interning of strings.

goos: darwin
goarch: arm64
pkg: bytes
                 │      old.txt       │               new.txt                │
                 │       sec/op       │    sec/op     vs base                │
Equal/same/1-8           2.678n ± ∞ ¹   2.400n ± ∞ ¹   -10.38% (p=0.008 n=5)
Equal/same/6-8           3.267n ± ∞ ¹   2.431n ± ∞ ¹   -25.59% (p=0.008 n=5)
Equal/same/9-8           2.981n ± ∞ ¹   2.385n ± ∞ ¹   -19.99% (p=0.008 n=5)
Equal/same/15-8          2.974n ± ∞ ¹   2.390n ± ∞ ¹   -19.64% (p=0.008 n=5)
Equal/same/16-8          2.983n ± ∞ ¹   2.380n ± ∞ ¹   -20.21% (p=0.008 n=5)
Equal/same/20-8          3.567n ± ∞ ¹   2.384n ± ∞ ¹   -33.17% (p=0.008 n=5)
Equal/same/32-8          3.568n ± ∞ ¹   2.385n ± ∞ ¹   -33.16% (p=0.008 n=5)
Equal/same/4K-8         78.040n ± ∞ ¹   2.378n ± ∞ ¹   -96.95% (p=0.008 n=5)
Equal/same/4M-8      78713.000n ± ∞ ¹   2.385n ± ∞ ¹  -100.00% (p=0.008 n=5)
Equal/same/64M-8   1348095.000n ± ∞ ¹   2.381n ± ∞ ¹  -100.00% (p=0.008 n=5)
geomean                  43.52n         2.390n         -94.51%
¹ need >= 6 samples for confidence interval at level 0.95

                 │    old.txt    │                     new.txt                      │
                 │      B/s      │         B/s          vs base                     │
Equal/same/1-8     356.1Mi ± ∞ ¹         397.3Mi ± ∞ ¹        +11.57% (p=0.008 n=5)
Equal/same/6-8     1.711Gi ± ∞ ¹         2.298Gi ± ∞ ¹        +34.35% (p=0.008 n=5)
Equal/same/9-8     2.812Gi ± ∞ ¹         3.515Gi ± ∞ ¹        +24.99% (p=0.008 n=5)
Equal/same/15-8    4.698Gi ± ∞ ¹         5.844Gi ± ∞ ¹        +24.41% (p=0.008 n=5)
Equal/same/16-8    4.995Gi ± ∞ ¹         6.260Gi ± ∞ ¹        +25.34% (p=0.008 n=5)
Equal/same/20-8    5.222Gi ± ∞ ¹         7.814Gi ± ∞ ¹        +49.63% (p=0.008 n=5)
Equal/same/32-8    8.353Gi ± ∞ ¹        12.496Gi ± ∞ ¹        +49.59% (p=0.008 n=5)
Equal/same/4K-8    48.88Gi ± ∞ ¹       1603.96Gi ± ∞ ¹      +3181.17% (p=0.008 n=5)
Equal/same/4M-8    49.63Gi ± ∞ ¹    1637911.85Gi ± ∞ ¹   +3300381.91% (p=0.008 n=5)
Equal/same/64M-8   46.36Gi ± ∞ ¹   26253069.97Gi ± ∞ ¹  +56626517.99% (p=0.008 n=5)
geomean            6.737Gi               122.7Gi            +1721.01%
¹ need >= 6 samples for confidence interval at level 0.95

Fixes #64381

Change-Id: I7d423930a688edd88c4ba60d45e097296d9be852
GitHub-Last-Rev: ae8189fafb1cba87b5394f09f971746ae9299273
GitHub-Pull-Request: golang/go#64419
Reviewed-on: https://go-review.googlesource.com/c/go/+/545416
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
2024-01-24 16:07:25 +00:00
Mark Ryan
03cd8a7b0e internal/bytealg: fix alignment code in equal_riscv64.s
The riscv64 implementation of equal has an optimization that is
applied when both pointers share the same alignment but that alignment
is not 8 bytes.  In this case it tries to align both pointers to an 8 byte boundaries,
by individually comparing the first few bytes of each buffer.  Unfortunately,
the existing code is incorrect.  It adjusts the pointers by the wrong number
of bytes resulting, in most cases, in pointers that are not 8 byte aligned.

This commit fixes the issue by individually comparing the first
(8 - (pointer & 7)) bytes of each buffer rather than the first
(pointer & 7) bytes.

This particular optimization is not covered by any of the existing
benchmarks so a new benchmark, BenchmarkEqualBothUnaligned,
is provided.  The benchmark tests the case where both pointers have
the same alignment but may not be 8 byte aligned.  Results of the
new benchmark along with some of the existing benchmarks generated on
a SiFive HiFive Unmatched A00 with 16GB of RAM running Ubuntu 23.04
are presented below.

Equal/0-4                                 3.356n ± 0%    3.357n ± 0%        ~ (p=0.840 n=10)
Equal/1-4                                 63.91n ± 7%    65.97n ± 5%   +3.22% (p=0.029 n=10)
Equal/6-4                                 72.94n ± 5%    76.09n ± 4%        ~ (p=0.075 n=10)
Equal/9-4                                 84.61n ± 7%    85.83n ± 3%        ~ (p=0.315 n=10)
Equal/15-4                                103.7n ± 2%    102.9n ± 4%        ~ (p=0.739 n=10)
Equal/16-4                                89.14n ± 3%   100.40n ± 4%  +12.64% (p=0.000 n=10)
Equal/20-4                                107.8n ± 3%    106.8n ± 3%        ~ (p=0.725 n=10)
Equal/32-4                                63.95n ± 8%    67.79n ± 7%        ~ (p=0.089 n=10)
Equal/4K-4                                1.256µ ± 1%    1.254µ ± 0%        ~ (p=0.925 n=10)
Equal/4M-4                                1.231m ± 0%    1.230m ± 0%   -0.04% (p=0.011 n=10)
Equal/64M-4                               19.77m ± 0%    19.78m ± 0%        ~ (p=0.052 n=10)
EqualBothUnaligned/64_0-4                 43.70n ± 4%    44.40n ± 5%        ~ (p=0.529 n=10)
EqualBothUnaligned/64_1-4                6957.5n ± 0%    105.9n ± 1%  -98.48% (p=0.000 n=10)
EqualBothUnaligned/64_4-4                 100.1n ± 2%    101.5n ± 4%        ~ (p=0.149 n=10)
EqualBothUnaligned/64_7-4               6965.00n ± 0%    95.60n ± 4%  -98.63% (p=0.000 n=10)
EqualBothUnaligned/4096_0-4               1.233µ ± 1%    1.225µ ± 0%   -0.65% (p=0.015 n=10)
EqualBothUnaligned/4096_1-4             584.226µ ± 0%    1.277µ ± 0%  -99.78% (p=0.000 n=10)
EqualBothUnaligned/4096_4-4               1.270µ ± 1%    1.268µ ± 0%        ~ (p=0.105 n=10)
EqualBothUnaligned/4096_7-4             584.944µ ± 0%    1.266µ ± 1%  -99.78% (p=0.000 n=10)
EqualBothUnaligned/4194304_0-4            1.241m ± 0%    1.236m ± 0%   -0.38% (p=0.035 n=10)
EqualBothUnaligned/4194304_1-4          600.956m ± 0%    1.238m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/4194304_4-4            1.239m ± 0%    1.241m ± 0%   +0.22% (p=0.007 n=10)
EqualBothUnaligned/4194304_7-4          601.036m ± 0%    1.239m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/67108864_0-4           19.79m ± 0%    19.78m ± 0%        ~ (p=0.393 n=10)
EqualBothUnaligned/67108864_1-4         9616.61m ± 0%    19.82m ± 0%  -99.79% (p=0.000 n=10)
EqualBothUnaligned/67108864_4-4           19.82m ± 0%    19.82m ± 0%        ~ (p=0.971 n=10)
EqualBothUnaligned/67108864_7-4         9616.34m ± 0%    19.86m ± 0%  -99.79% (p=0.000 n=10)
geomean                                   38.38µ         7.194µ       -81.26%

Change-Id: I4caab6c3450bd7e2773426b08b70bbc37fbe4e5f
Reviewed-on: https://go-review.googlesource.com/c/go/+/500855
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2023-06-29 02:34:59 +00:00
hopehook
0b3f58c48e bytes, strings: add ContainsFunc
Fixes #54386.

Change-Id: I78747da337ed6129e4f7426dd0483a644bed82e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/460216
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: hopehook <hopehook@golangcn.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
2023-01-24 22:06:45 +00:00
fangguizhen
e590afcf2c bytes, strings: rename field in CutSuffix tests
Change-Id: I63181f6540fc1bfcfc988a16bf9fafbd3575cfdf
GitHub-Last-Rev: d90528730a92a087866c1bfc227a0a0bf1cdffbe
GitHub-Pull-Request: golang/go#57909
Reviewed-on: https://go-review.googlesource.com/c/go/+/462284
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2023-01-20 01:25:45 +00:00
Carlo Alberto Ferraris
dcb90152a4 bytes,strings: optimize Repeat
When generating long strings or slices with Repeat we
currently reuse intermediate states as a way to quickly
build exponentially longer results.

This works well as long as the intermediate states fit into
the processor D-cache. If they don't we start thrashing the
D-cache by reading in the whole intermediate state over and
over on each iteration.

Instead, once we reach a large enough intermediate state (that
allows the memcpy operation to perform at peak) we cap the
size of chunk of the state that is used as source for subsequent
appends. This ensures that this smaller source chunk is always
present in the D-cache, and the append operation does not need
to read the state contents from memory.

Currently the cap is set to 8KB, a number derived via
experimentation to yield the highest performance across a
a large range of result sizes. Slightly higher caps also
produced similar results: 8KB was chosen as the smallest one
in this performance plateau with the intention to minimize
D-cache pollution.

For result sizes larger than the fastest cache levels we get
significantly higher performance compared to the current
implementation:
strings:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.73GB/s ± 1%  1.73GB/s ± 0%      ~     (p=0.556 n=5+4)
RepeatLarge/256/16-16           2.02GB/s ± 0%  1.95GB/s ± 8%      ~     (p=0.222 n=5+5)
RepeatLarge/512/1-16            2.30GB/s ±13%  2.47GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/512/16-16           2.38GB/s ±16%  2.77GB/s ± 1%   +16.27%  (p=0.032 n=5+5)
RepeatLarge/1024/1-16           3.17GB/s ± 1%  3.18GB/s ± 0%      ~     (p=0.730 n=4+5)
RepeatLarge/1024/16-16          3.39GB/s ± 2%  3.38GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/2048/1-16           3.32GB/s ± 2%  3.32GB/s ± 2%      ~     (p=1.000 n=5+5)
RepeatLarge/2048/16-16          3.41GB/s ± 4%  3.46GB/s ± 2%      ~     (p=0.310 n=5+5)
RepeatLarge/4096/1-16           3.60GB/s ± 4%  3.67GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/4096/16-16          3.74GB/s ± 3%  3.71GB/s ± 5%      ~     (p=0.690 n=5+5)
RepeatLarge/8192/1-16           3.94GB/s ± 4%  4.01GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/16-16          3.94GB/s ± 6%  4.05GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/4097-16        4.25GB/s ± 6%  4.32GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/16384/1-16          4.96GB/s ± 1%  5.02GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/16-16         4.99GB/s ± 2%  5.07GB/s ± 1%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/4097-16       5.15GB/s ± 3%  5.17GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/32768/1-16          5.44GB/s ± 2%  5.42GB/s ± 1%      ~     (p=0.841 n=5+5)
RepeatLarge/32768/16-16         5.46GB/s ± 4%  5.44GB/s ± 1%      ~     (p=0.905 n=5+4)
RepeatLarge/32768/4097-16       4.84GB/s ± 2%  4.59GB/s ±12%    -5.05%  (p=0.032 n=5+5)
RepeatLarge/65536/1-16          5.85GB/s ± 0%  5.84GB/s ± 1%      ~     (p=0.690 n=5+5)
RepeatLarge/65536/16-16         5.81GB/s ± 2%  5.84GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/65536/4097-16       5.38GB/s ± 6%  5.45GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/131072/1-16         6.20GB/s ± 1%  6.31GB/s ± 1%    +1.80%  (p=0.008 n=5+5)
RepeatLarge/131072/16-16        6.12GB/s ± 3%  6.25GB/s ± 3%      ~     (p=0.095 n=5+5)
RepeatLarge/131072/4097-16      5.95GB/s ± 1%  5.85GB/s ±10%      ~     (p=1.000 n=5+5)
RepeatLarge/262144/1-16         6.33GB/s ± 1%  6.56GB/s ± 0%    +3.62%  (p=0.016 n=5+4)
RepeatLarge/262144/16-16        6.42GB/s ± 0%  6.65GB/s ± 1%    +3.58%  (p=0.016 n=4+5)
RepeatLarge/262144/4097-16      6.31GB/s ± 1%  6.44GB/s ± 1%    +1.94%  (p=0.008 n=5+5)
RepeatLarge/524288/1-16         6.23GB/s ± 1%  6.92GB/s ± 3%   +11.02%  (p=0.008 n=5+5)
RepeatLarge/524288/16-16        6.24GB/s ± 1%  6.97GB/s ± 2%   +11.77%  (p=0.016 n=4+5)
RepeatLarge/524288/4097-16      6.14GB/s ± 2%  6.73GB/s ± 3%    +9.50%  (p=0.008 n=5+5)
RepeatLarge/1048576/1-16        5.23GB/s ± 1%  6.53GB/s ± 6%   +24.85%  (p=0.008 n=5+5)
RepeatLarge/1048576/16-16       5.21GB/s ± 1%  6.56GB/s ± 4%   +25.93%  (p=0.008 n=5+5)
RepeatLarge/1048576/4097-16     5.22GB/s ± 1%  6.26GB/s ± 2%   +20.09%  (p=0.008 n=5+5)
RepeatLarge/2097152/1-16        3.95GB/s ± 1%  5.96GB/s ± 1%   +51.01%  (p=0.008 n=5+5)
RepeatLarge/2097152/16-16       3.94GB/s ± 1%  5.98GB/s ± 2%   +51.99%  (p=0.008 n=5+5)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  5.71GB/s ± 2%   +15.63%  (p=0.008 n=5+5)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.89GB/s ± 1%   +89.90%  (p=0.008 n=5+5)
RepeatLarge/4194304/16-16       3.09GB/s ± 1%  5.86GB/s ± 1%   +89.89%  (p=0.008 n=5+5)
RepeatLarge/4194304/4097-16     3.13GB/s ± 1%  5.89GB/s ± 1%   +88.36%  (p=0.008 n=5+5)
RepeatLarge/8388608/1-16        3.06GB/s ± 1%  6.31GB/s ±16%  +105.84%  (p=0.008 n=5+5)
RepeatLarge/8388608/16-16       3.08GB/s ± 1%  6.62GB/s ± 1%  +114.66%  (p=0.008 n=5+5)
RepeatLarge/8388608/4097-16     3.13GB/s ± 2%  6.87GB/s ± 1%  +119.62%  (p=0.008 n=5+5)
RepeatLarge/16777216/1-16       3.21GB/s ± 3%  5.88GB/s ± 1%   +83.27%  (p=0.008 n=5+5)
RepeatLarge/16777216/16-16      3.23GB/s ± 2%  5.84GB/s ± 2%   +80.49%  (p=0.008 n=5+5)
RepeatLarge/16777216/4097-16    3.30GB/s ± 6%  5.88GB/s ± 2%   +78.18%  (p=0.008 n=5+5)
RepeatLarge/33554432/1-16       3.71GB/s ± 3%  5.91GB/s ± 2%   +59.17%  (p=0.008 n=5+5)
RepeatLarge/33554432/16-16      3.67GB/s ± 3%  5.91GB/s ± 2%   +61.13%  (p=0.008 n=5+5)
RepeatLarge/33554432/4097-16    3.71GB/s ± 1%  5.77GB/s ± 6%   +55.51%  (p=0.008 n=5+5)
RepeatLarge/67108864/1-16       4.61GB/s ±11%  6.00GB/s ± 5%   +30.15%  (p=0.008 n=5+5)
RepeatLarge/67108864/16-16      4.62GB/s ± 7%  6.11GB/s ± 2%   +32.35%  (p=0.008 n=5+5)
RepeatLarge/67108864/4097-16    4.71GB/s ± 2%  6.24GB/s ± 2%   +32.60%  (p=0.008 n=5+5)
RepeatLarge/134217728/1-16      4.53GB/s ± 8%  6.28GB/s ±11%   +38.57%  (p=0.008 n=5+5)
RepeatLarge/134217728/16-16     4.78GB/s ± 3%  6.36GB/s ± 3%   +33.16%  (p=0.008 n=5+5)
RepeatLarge/134217728/4097-16   4.73GB/s ± 6%  6.46GB/s ± 3%   +36.63%  (p=0.008 n=5+5)
RepeatLarge/268435456/1-16      4.09GB/s ±25%  6.37GB/s ±19%   +56.00%  (p=0.008 n=5+5)
RepeatLarge/268435456/16-16     4.50GB/s ± 4%  6.86GB/s ± 0%   +52.49%  (p=0.016 n=5+4)
RepeatLarge/268435456/4097-16   4.73GB/s ± 5%  6.90GB/s ± 0%   +45.94%  (p=0.008 n=5+5)
RepeatLarge/536870912/1-16      4.38GB/s ±36%  6.52GB/s ± 8%   +48.68%  (p=0.008 n=5+5)
RepeatLarge/536870912/16-16     4.69GB/s ±12%  6.90GB/s ± 1%   +46.97%  (p=0.008 n=5+5)
RepeatLarge/536870912/4097-16   4.87GB/s ± 8%  6.98GB/s ± 0%   +43.36%  (p=0.008 n=5+5)
RepeatLarge/1073741824/1-16     3.87GB/s ±28%  6.96GB/s ± 1%   +79.94%  (p=0.016 n=5+4)
RepeatLarge/1073741824/16-16    4.79GB/s ± 9%  6.93GB/s ± 0%   +44.79%  (p=0.008 n=5+5)
RepeatLarge/1073741824/4097-16  4.65GB/s ± 8%  7.02GB/s ± 1%   +51.02%  (p=0.008 n=5+5)

bytes:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.93GB/s ± 1%  1.84GB/s ± 1%    -4.81%  (p=0.000 n=10+10)
RepeatLarge/256/16-16           2.25GB/s ± 2%  2.15GB/s ± 1%    -4.45%  (p=0.000 n=9+8)
RepeatLarge/512/1-16            2.71GB/s ± 1%  2.62GB/s ± 1%    -3.27%  (p=0.000 n=10+9)
RepeatLarge/512/16-16           2.96GB/s ± 4%  2.91GB/s ± 1%      ~     (p=0.243 n=9+10)
RepeatLarge/1024/1-16           3.35GB/s ± 1%  3.27GB/s ± 1%    -2.61%  (p=0.000 n=9+10)
RepeatLarge/1024/16-16          3.56GB/s ± 2%  3.52GB/s ± 1%    -1.10%  (p=0.010 n=10+9)
RepeatLarge/2048/1-16           3.52GB/s ± 1%  3.45GB/s ± 1%    -1.92%  (p=0.000 n=10+10)
RepeatLarge/2048/16-16          3.61GB/s ± 1%  3.58GB/s ± 0%    -0.82%  (p=0.008 n=9+8)
RepeatLarge/4096/1-16           3.85GB/s ± 2%  3.80GB/s ± 2%      ~     (p=0.165 n=10+10)
RepeatLarge/4096/16-16          3.88GB/s ± 3%  3.84GB/s ± 4%      ~     (p=0.393 n=10+10)
RepeatLarge/8192/1-16           4.12GB/s ± 2%  4.04GB/s ± 1%    -1.96%  (p=0.000 n=10+10)
RepeatLarge/8192/16-16          4.11GB/s ± 2%  4.09GB/s ± 1%      ~     (p=0.278 n=9+10)
RepeatLarge/8192/4097-16        4.38GB/s ± 1%  4.39GB/s ± 4%      ~     (p=0.720 n=9+10)
RepeatLarge/16384/1-16          5.06GB/s ± 2%  4.95GB/s ± 3%    -2.29%  (p=0.001 n=10+9)
RepeatLarge/16384/16-16         5.11GB/s ± 3%  5.06GB/s ± 3%      ~     (p=0.315 n=10+9)
RepeatLarge/16384/4097-16       5.22GB/s ± 3%  5.26GB/s ± 3%      ~     (p=0.211 n=9+10)
RepeatLarge/32768/1-16          5.54GB/s ± 2%  5.50GB/s ± 3%      ~     (p=0.353 n=10+10)
RepeatLarge/32768/16-16         5.55GB/s ± 1%  5.60GB/s ± 1%    +0.91%  (p=0.035 n=10+9)
RepeatLarge/32768/4097-16       4.88GB/s ± 2%  4.85GB/s ± 2%      ~     (p=0.447 n=10+9)
RepeatLarge/65536/1-16          5.86GB/s ± 1%  5.93GB/s ± 2%    +1.18%  (p=0.043 n=8+10)
RepeatLarge/65536/16-16         5.83GB/s ± 2%  5.98GB/s ± 1%    +2.67%  (p=0.000 n=10+10)
RepeatLarge/65536/4097-16       5.57GB/s ± 0%  5.56GB/s ± 3%      ~     (p=0.696 n=8+10)
RepeatLarge/131072/1-16         6.23GB/s ± 1%  6.38GB/s ± 2%    +2.51%  (p=0.000 n=9+10)
RepeatLarge/131072/16-16        6.21GB/s ± 2%  6.37GB/s ± 1%    +2.72%  (p=0.000 n=9+10)
RepeatLarge/131072/4097-16      6.04GB/s ± 1%  6.09GB/s ± 3%      ~     (p=0.356 n=9+10)
RepeatLarge/262144/1-16         6.47GB/s ± 1%  6.63GB/s ± 2%    +2.57%  (p=0.003 n=10+10)
RepeatLarge/262144/16-16        6.45GB/s ± 2%  6.69GB/s ± 2%    +3.65%  (p=0.000 n=10+10)
RepeatLarge/262144/4097-16      6.35GB/s ± 1%  6.51GB/s ± 2%    +2.48%  (p=0.000 n=9+10)
RepeatLarge/524288/1-16         6.21GB/s ± 2%  6.95GB/s ± 1%   +11.95%  (p=0.000 n=10+10)
RepeatLarge/524288/16-16        6.24GB/s ± 2%  6.93GB/s ± 2%   +11.11%  (p=0.000 n=10+10)
RepeatLarge/524288/4097-16      6.18GB/s ± 2%  6.82GB/s ± 1%   +10.39%  (p=0.000 n=9+10)
RepeatLarge/1048576/1-16        5.34GB/s ± 2%  6.41GB/s ± 2%   +20.05%  (p=0.000 n=10+10)
RepeatLarge/1048576/16-16       5.33GB/s ± 1%  6.45GB/s ± 2%   +20.84%  (p=0.000 n=10+9)
RepeatLarge/1048576/4097-16     5.28GB/s ± 1%  6.17GB/s ± 2%   +16.75%  (p=0.000 n=10+10)
RepeatLarge/2097152/1-16        4.04GB/s ± 1%  6.21GB/s ± 1%   +53.89%  (p=0.000 n=9+8)
RepeatLarge/2097152/16-16       4.02GB/s ± 1%  6.20GB/s ± 2%   +54.37%  (p=0.000 n=10+9)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  6.04GB/s ± 1%   +22.36%  (p=0.000 n=10+10)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.74GB/s ± 0%   +85.04%  (p=0.000 n=10+9)
RepeatLarge/4194304/16-16       3.10GB/s ± 2%  5.72GB/s ± 1%   +84.26%  (p=0.000 n=9+10)
RepeatLarge/4194304/4097-16     3.03GB/s ± 4%  5.61GB/s ± 1%   +85.06%  (p=0.000 n=10+9)
RepeatLarge/8388608/1-16        3.08GB/s ± 2%  6.25GB/s ± 1%  +103.09%  (p=0.000 n=9+9)
RepeatLarge/8388608/16-16       3.07GB/s ± 2%  6.26GB/s ± 3%  +104.07%  (p=0.000 n=10+9)
RepeatLarge/8388608/4097-16     3.08GB/s ± 2%  6.23GB/s ± 2%  +102.09%  (p=0.000 n=9+10)
RepeatLarge/16777216/1-16       3.25GB/s ± 2%  5.78GB/s ± 3%   +78.03%  (p=0.000 n=9+9)
RepeatLarge/16777216/16-16      3.25GB/s ± 1%  5.75GB/s ± 1%   +77.21%  (p=0.000 n=9+10)
RepeatLarge/16777216/4097-16    3.29GB/s ± 3%  5.72GB/s ± 2%   +73.74%  (p=0.000 n=10+10)
RepeatLarge/33554432/1-16       3.68GB/s ± 2%  5.90GB/s ± 1%   +60.20%  (p=0.000 n=10+10)
RepeatLarge/33554432/16-16      3.69GB/s ± 3%  5.88GB/s ± 1%   +59.54%  (p=0.000 n=10+9)
RepeatLarge/33554432/4097-16    3.74GB/s ± 1%  5.94GB/s ± 2%   +58.68%  (p=0.000 n=7+10)
RepeatLarge/67108864/1-16       4.62GB/s ±12%  6.11GB/s ± 3%   +32.23%  (p=0.000 n=10+9)
RepeatLarge/67108864/16-16      4.77GB/s ± 2%  6.09GB/s ± 2%   +27.88%  (p=0.000 n=9+9)
RepeatLarge/67108864/4097-16    4.78GB/s ± 1%  6.19GB/s ± 1%   +29.51%  (p=0.000 n=9+10)
RepeatLarge/134217728/1-16      4.60GB/s ±16%  6.52GB/s ± 9%   +41.67%  (p=0.000 n=10+10)
RepeatLarge/134217728/16-16     4.80GB/s ± 4%  6.81GB/s ± 2%   +41.82%  (p=0.000 n=10+9)
RepeatLarge/134217728/4097-16   4.79GB/s ± 4%  6.81GB/s ± 2%   +42.31%  (p=0.000 n=9+10)
RepeatLarge/268435456/1-16      4.43GB/s ±25%  6.27GB/s ±14%   +41.52%  (p=0.000 n=10+10)
RepeatLarge/268435456/16-16     4.75GB/s ± 4%  6.68GB/s ± 4%   +40.50%  (p=0.000 n=9+10)
RepeatLarge/268435456/4097-16   4.75GB/s ± 3%  6.58GB/s ± 4%   +38.68%  (p=0.000 n=9+10)
RepeatLarge/536870912/1-16      4.96GB/s ± 9%  6.39GB/s ±16%   +28.90%  (p=0.000 n=8+10)
RepeatLarge/536870912/16-16     4.66GB/s ± 6%  6.57GB/s ± 7%   +40.82%  (p=0.000 n=10+9)
RepeatLarge/536870912/4097-16   4.68GB/s ±11%  6.88GB/s ± 3%   +47.01%  (p=0.000 n=10+9)
RepeatLarge/1073741824/1-16     4.39GB/s ±23%  6.57GB/s ± 5%   +49.75%  (p=0.000 n=10+8)
RepeatLarge/1073741824/16-16    4.73GB/s ±13%  6.89GB/s ± 1%   +45.68%  (p=0.000 n=9+8)
RepeatLarge/1073741824/4097-16  4.97GB/s ±15%  6.73GB/s ± 9%   +35.45%  (p=0.000 n=10+10)

The results above come from a Intel i9-9980HK (256KB L2) with
TurboBoost disabled.

Change-Id: I79dd57da0429aee9020ffd7bc458a034b999b740
Reviewed-on: https://go-review.googlesource.com/c/go/+/419054
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-09-27 16:55:15 +00:00
cuiweixie
2a627afe13 bytes: simplify code using unsafe.SliceData
Updates #54854

Change-Id: I9c14f9fa595f73eae44eb714abc5d486915893c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/428155
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2022-09-07 01:33:52 +00:00
Changkun Ou
68005592b3 strings, bytes: add CutPrefix and CutSuffix
Fixes #42537

Change-Id: Ie03c2614ffee30ebe707acad6b9f6c28fb134a45
Reviewed-on: https://go-review.googlesource.com/c/go/+/407176
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Changkun Ou <mail@changkun.de>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2022-08-16 19:48:39 +00:00
Martin Möhrmann
7b45edb450 bytes: add Clone function
The new Clone function returns a copy of b[:len(b)]
for the input byte slice b.
The result may have additional unused capacity.
Clone(nil) returns nil.

Fixes #45038

Change-Id: I0469a202d77a7b491f1341c08915d07ddd1f0300
Reviewed-on: https://go-review.googlesource.com/c/go/+/359675
Run-TryBot: Martin Möhrmann <martin@golang.org>
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Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2022-08-15 19:17:20 +00:00
Joe Tsai
9a4685f220 strings: avoid utf8.RuneError mangling in Split
Split should only split strings and not perform mangling
of invalid UTF-8 into ut8.RuneError.
The prior behavior is clearly a bug since mangling is not
performed in all other situations (e.g., separator is non-empty).

Fixes #53511

Change-Id: I112a2ef15ee46ddecda015ee14bca04cd76adfbf
Reviewed-on: https://go-review.googlesource.com/c/go/+/413715
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-08-08 20:44:51 +00:00
Archana R
7ca1e2aa56 internal/bytealg: optimize index function for ppc64le/power9
Optimized index2to16 loop by unrolling the loop by 4.
Multiple benchmark tests show performance improvement on
POWER9. Similar improvements are seen on POWER10. Added
tests to ensure changes work fine.

name            old time/op   new time/op    delta
Index/10         18.3ns ± 0%    19.7ns ±25%     ~
Index/32         75.3ns ± 0%    69.2ns ± 0%   -8.22%
Index/4K         5.53µs ± 0%    3.69µs ± 0%  -33.20%
Index/4M         5.64ms ± 0%    3.75ms ± 0%  -33.55%
Index/64M        92.9ms ± 0%    61.6ms ± 0%  -33.69%
IndexHard2       1.41ms ± 0%    0.93ms ± 0%  -33.75%
CountHard2       1.41ms ± 0%    0.93ms ± 0%  -33.75%

Change-Id: If9331df6a141a4716724b8cb648d2b91bdf17e5f
Reviewed-on: https://go-review.googlesource.com/c/go/+/377016
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
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Run-TryBot: Archana Ravindar <aravind5@in.ibm.com>
2022-05-09 12:02:02 +00:00
Philippe Antoine
5bb2628c6f bytes: limit allocation in SplitN
So that bytes.SplitN("", "T", int(144115188075855872)) does not panic.

Change-Id: I7c068852bd708416164fc2ed8b84cf6b2d593666
GitHub-Last-Rev: f8df09d65e2bc889fbd0c736bfb5e9a9078dfced
GitHub-Pull-Request: golang/go#52147
Reviewed-on: https://go-review.googlesource.com/c/go/+/398076
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: mzh <mzh@golangcn.org>
2022-04-06 03:13:34 +00:00
Ian Lance Taylor
32fdad19a2 bytes: restore old Trim/TrimLeft behavior for nil
Keep returning nil for the cases where we historically returned nil,
even though this is slightly different for TrimLeft and TrimRight.

Fixes #51793

Change-Id: Ifbdfc6b09d52b8e063cfe6341019f9b2eb8b70e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/393876
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2022-03-28 22:06:49 +00:00
Russ Cox
8e36ab0551 bytes, strings: add Cut
Using Cut is a clearer way to write the vast majority (>70%)
of existing code that calls Index, IndexByte, IndexRune, and SplitN.
There is more discussion on https://golang.org/issue/46336.

Fixes #46336.

Change-Id: Ia418ed7c3706c65bf61e1b2c5baf534cb783e4d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/351710
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-10-06 15:53:00 +00:00
Joe Tsai
5baf60d472 bytes, strings: optimize Trim for single byte cutsets
Using the latest version of all modules known by the module proxy,
we determine that for all Trim usages (and related functionality):
* 76.6% have cutsets of len=1, and
* 13.4% have cutsets of len=2.

Given that a vast majority of usages only have a cutset of len=1,
we should more heavily optimize for that situation.
Previously, there was some optimization for cutsets of len=1,
but it's within the internal makeCutsetFunc function.
This is sub-optimal as it incurs an allocation in makeCutsetFunc
for the closure over that single byte.

This CL removes special-casing of one-byte cutsets from makeCutsetFunc
and instead distributes it directly in Trim, TrimRight, and TrimLeft.
Whether we should distribute the entire ASCII cutset logic into Trim
is a future CL that should be discussed and handled separately.
The evidence for multibyte cutsets is not as obviously compelling.

name                old time/op  new time/op  delta
bytes/TrimByte-4    84.1ns ± 2%   7.5ns ± 1%  -91.10%  (p=0.000 n=9+7)
strings/TrimByte-4  86.2ns ± 3%   8.3ns ± 1%  -90.33%  (p=0.000 n=9+10)

Fixes #46446

Change-Id: Ia0e31a8384c3ce111ae35465605bcec45df2ebec
Reviewed-on: https://go-review.googlesource.com/c/go/+/323318
Trust: Joe Tsai <joetsai@digital-static.net>
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
2021-08-25 19:29:15 +00:00
erifan01
3af92acb9f strings, bytes: improve IndexAny and LastIndexAny performance
For the case of a pattern containing multi-byte rune, the time complexity of the
previous algorithm is O(nm), and if both input arguments are long, the search
performance will be poor. This CL improves the searching performance for these
cases by using IndexRune, which is mainly implemented with IndexByte and Index.
As IndexByte and Index are specially optimized with some powerful instructions
for short patterns (an UTF8 rune is 1 to 4 bytes), so they can help to reduce the
runtime complexity of IndexAny and LastIndexAny.

Another optimization method is using hash table, however, the actual test results
show that using indexrune is better, and the space complexity is lower.

There are two fast paths in IndexAny and LastIndexAny for cases where the length
of the input arguements are 1, and their locations are not exactly the same, which
is determined based on the actual test results.

Benchmarks on arm64 and amd64:

name                        old time/op  new time/op  delta
pkg:strings goos:linux goarch:arm64
IndexAnyASCII/1:1-8         23.7ns ± 3%  28.5ns ± 0%  +20.15%  (p=0.008 n=5+5)
IndexAnyASCII/1:2-8         18.0ns ± 0%  33.1ns ± 0%  +83.67%  (p=0.008 n=5+5)
IndexAnyASCII/1:4-8         20.0ns ± 0%  36.0ns ± 0%  +80.00%  (p=0.029 n=4+4)
IndexAnyASCII/1:8-8         36.1ns ± 0%  36.0ns ± 0%     ~     (p=0.095 n=5+4)
IndexAnyASCII/1:16-8        48.1ns ± 0%  36.0ns ± 0%  -25.19%  (p=0.029 n=4+4)
IndexAnyASCII/1:32-8        72.1ns ± 0%  36.0ns ± 0%  -50.01%  (p=0.008 n=5+5)
IndexAnyASCII/1:64-8         120ns ± 0%    39ns ± 0%  -67.83%  (p=0.008 n=5+5)
IndexAnyASCII/16:1-8        73.0ns ± 0%  28.5ns ± 0%  -60.95%  (p=0.008 n=5+5)
IndexAnyASCII/16:2-8        76.8ns ± 0%  77.0ns ± 0%     ~     (p=1.000 n=5+5)
IndexAnyASCII/16:4-8        83.2ns ± 1%  83.0ns ± 0%     ~     (p=0.770 n=5+5)
IndexAnyASCII/16:8-8         111ns ± 1%   107ns ± 0%   -3.25%  (p=0.008 n=5+5)
IndexAnyASCII/16:16-8        139ns ± 1%   137ns ± 0%   -1.58%  (p=0.008 n=5+5)
IndexAnyASCII/16:32-8        199ns ± 1%   197ns ± 0%   -1.20%  (p=0.008 n=5+5)
IndexAnyASCII/16:64-8        307ns ± 0%   313ns ± 0%   +1.82%  (p=0.016 n=5+4)
IndexAnyASCII/256:1-8        674ns ± 0%    65ns ± 0%  -90.31%  (p=0.008 n=5+5)
IndexAnyASCII/256:2-8        678ns ± 0%   683ns ± 0%   +0.68%  (p=0.008 n=5+5)
IndexAnyASCII/256:4-8        685ns ± 0%   683ns ± 0%   -0.29%  (p=0.000 n=5+4)
IndexAnyASCII/256:8-8        711ns ± 0%   708ns ± 0%   -0.48%  (p=0.008 n=5+5)
IndexAnyASCII/256:16-8       740ns ± 0%   740ns ± 0%     ~     (p=0.444 n=5+5)
IndexAnyASCII/256:32-8       799ns ± 0%   798ns ± 0%   -0.18%  (p=0.008 n=5+5)
IndexAnyASCII/256:64-8       910ns ± 0%   914ns ± 0%   +0.44%  (p=0.016 n=4+5)
IndexAnyUTF8/1:1-8          27.1ns ± 0%  19.0ns ± 0%  -29.79%  (p=0.008 n=5+5)
IndexAnyUTF8/1:2-8          44.1ns ± 0%  33.0ns ± 0%  -25.17%  (p=0.008 n=5+5)
IndexAnyUTF8/1:4-8          46.1ns ± 0%  33.1ns ± 0%  -28.29%  (p=0.016 n=4+5)
IndexAnyUTF8/1:8-8          85.1ns ± 0%  33.0ns ± 0%  -61.18%  (p=0.008 n=5+5)
IndexAnyUTF8/1:16-8          110ns ± 1%    36ns ± 0%  -67.27%  (p=0.008 n=5+5)
IndexAnyUTF8/1:32-8          188ns ± 0%    36ns ± 0%  -80.85%  (p=0.008 n=5+5)
IndexAnyUTF8/1:64-8          332ns ± 0%    39ns ± 0%     ~     (p=0.079 n=4+5)
IndexAnyUTF8/16:1-8          293ns ± 0%    54ns ± 0%  -81.56%  (p=0.008 n=5+5)
IndexAnyUTF8/16:2-8          563ns ± 0%   349ns ± 0%  -37.98%  (p=0.008 n=5+5)
IndexAnyUTF8/16:4-8          546ns ± 1%   349ns ± 0%  -36.10%  (p=0.000 n=5+4)
IndexAnyUTF8/16:8-8         1.22µs ± 0%  0.35µs ± 0%  -71.39%  (p=0.008 n=5+5)
IndexAnyUTF8/16:16-8        1.63µs ± 1%  0.42µs ± 0%  -73.98%  (p=0.008 n=5+5)
IndexAnyUTF8/16:32-8        2.87µs ± 0%  0.42µs ± 0%  -85.22%  (p=0.008 n=5+5)
IndexAnyUTF8/16:64-8        5.18µs ± 0%  0.47µs ± 0%  -90.98%  (p=0.008 n=5+5)
IndexAnyUTF8/256:1-8        4.26µs ± 0%  0.47µs ± 0%  -88.85%  (p=0.000 n=4+5)
IndexAnyUTF8/256:2-8        8.62µs ± 0%  5.15µs ± 0%  -40.21%  (p=0.008 n=5+5)
IndexAnyUTF8/256:4-8        8.25µs ± 0%  5.15µs ± 0%  -37.50%  (p=0.016 n=5+4)
IndexAnyUTF8/256:8-8        19.2µs ± 1%   5.2µs ± 0%  -73.08%  (p=0.016 n=5+4)
IndexAnyUTF8/256:16-8       25.6µs ± 1%   6.3µs ± 0%  -75.32%  (p=0.008 n=5+5)
IndexAnyUTF8/256:32-8       45.6µs ± 0%   6.3µs ± 0%  -86.15%  (p=0.008 n=5+5)
IndexAnyUTF8/256:64-8       82.4µs ± 0%   7.0µs ± 0%  -91.53%  (p=0.016 n=5+4)
LastIndexAnyASCII/1:1-8     23.0ns ± 0%  33.5ns ± 0%  +45.65%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:2-8     24.5ns ± 0%  33.5ns ± 0%  +36.73%  (p=0.016 n=4+5)
LastIndexAnyASCII/1:4-8     27.5ns ± 0%  35.5ns ± 0%  +29.09%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:8-8     44.5ns ± 0%  35.5ns ± 0%  -20.13%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:16-8    56.5ns ± 0%  35.5ns ± 0%  -37.15%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:32-8    80.3ns ± 0%  35.5ns ± 0%  -55.79%  (p=0.000 n=5+4)
LastIndexAnyASCII/1:64-8     129ns ± 0%    40ns ± 0%  -68.85%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:1-8    72.8ns ± 0%  72.7ns ± 0%   -0.19%  (p=0.016 n=4+5)
LastIndexAnyASCII/16:2-8    75.4ns ± 0%  75.1ns ± 0%     ~     (p=0.127 n=5+5)
LastIndexAnyASCII/16:4-8    81.9ns ± 1%  80.2ns ± 0%   -2.00%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:8-8     110ns ± 1%   108ns ± 0%   -1.46%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:16-8    138ns ± 1%   134ns ± 0%   -3.18%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:32-8    198ns ± 0%   197ns ± 0%   -0.51%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:64-8    309ns ± 0%   313ns ± 0%   +1.30%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:1-8    652ns ± 0%   653ns ± 0%   +0.21%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:2-8    656ns ± 0%   656ns ± 0%     ~     (all equal)
LastIndexAnyASCII/256:4-8    663ns ± 0%   663ns ± 0%     ~     (p=0.444 n=5+5)
LastIndexAnyASCII/256:8-8    691ns ± 0%   690ns ± 0%     ~     (p=0.079 n=4+5)
LastIndexAnyASCII/256:16-8   719ns ± 0%   715ns ± 0%   -0.53%  (p=0.000 n=5+4)
LastIndexAnyASCII/256:32-8   779ns ± 0%   780ns ± 0%   +0.13%  (p=0.029 n=4+4)
LastIndexAnyASCII/256:64-8   890ns ± 0%   894ns ± 0%   +0.45%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:1-8      31.6ns ± 0%  33.5ns ± 0%   +6.01%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:2-8      48.6ns ± 0%  33.5ns ± 0%  -30.99%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:4-8      48.6ns ± 0%  33.5ns ± 0%  -31.13%  (p=0.000 n=5+4)
LastIndexAnyUTF8/1:8-8      89.6ns ± 0%  33.5ns ± 0%  -62.56%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:16-8      113ns ± 1%    36ns ± 0%  -68.47%  (p=0.000 n=5+4)
LastIndexAnyUTF8/1:32-8      190ns ± 0%    36ns ± 0%  -81.26%  (p=0.029 n=4+4)
LastIndexAnyUTF8/1:64-8      327ns ± 0%    40ns ± 0%  -87.77%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:1-8      364ns ± 0%   158ns ± 0%     ~     (p=0.079 n=4+5)
LastIndexAnyUTF8/16:2-8      636ns ± 0%   472ns ± 0%  -25.79%  (p=0.000 n=5+4)
LastIndexAnyUTF8/16:4-8      630ns ± 0%   472ns ± 0%  -25.03%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:8-8     1.28µs ± 0%  0.47µs ± 0%  -63.09%  (p=0.016 n=5+4)
LastIndexAnyUTF8/16:16-8    1.66µs ± 0%  0.53µs ± 0%  -68.39%  (p=0.016 n=5+4)
LastIndexAnyUTF8/16:32-8    2.88µs ± 0%  0.53µs ± 0%  -81.72%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:64-8    5.08µs ± 0%  0.57µs ± 0%  -88.79%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:1-8    5.41µs ± 0%  2.03µs ± 0%  -62.46%  (p=0.016 n=4+5)
LastIndexAnyUTF8/256:2-8    9.77µs ± 0%  7.14µs ± 0%  -26.97%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:4-8    9.63µs ± 0%  7.14µs ± 0%  -25.86%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:8-8    20.0µs ± 0%   7.1µs ± 0%  -64.30%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:16-8   26.1µs ± 1%   8.0µs ± 0%  -69.40%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:32-8   45.6µs ± 1%   8.0µs ± 0%  -82.51%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:64-8   80.8µs ± 0%   8.6µs ± 0%  -89.33%  (p=0.016 n=5+4)
pkg:bytes goos:linux goarch:arm64
IndexAnyASCII/1:1-8         26.2ns ± 1%  26.5ns ± 0%   +1.30%  (p=0.016 n=5+4)
IndexAnyASCII/1:2-8         18.5ns ± 0%  26.5ns ± 0%  +43.24%  (p=0.008 n=5+5)
IndexAnyASCII/1:4-8         21.0ns ± 0%  26.5ns ± 0%  +26.38%  (p=0.008 n=5+5)
IndexAnyASCII/1:8-8         37.5ns ± 0%  26.5ns ± 0%  -29.33%  (p=0.000 n=5+4)
IndexAnyASCII/1:16-8        49.6ns ± 0%  26.5ns ± 0%  -46.49%  (p=0.008 n=5+5)
IndexAnyASCII/1:32-8        73.6ns ± 0%  30.1ns ± 0%  -59.16%  (p=0.008 n=5+5)
IndexAnyASCII/1:64-8         122ns ± 0%    33ns ± 0%  -73.23%  (p=0.008 n=5+5)
IndexAnyASCII/16:1-8        73.7ns ± 0%  33.4ns ± 0%  -54.71%  (p=0.008 n=5+5)
IndexAnyASCII/16:2-8        79.1ns ± 0%  78.9ns ± 0%   -0.30%  (p=0.016 n=4+5)
IndexAnyASCII/16:4-8        84.8ns ± 0%  86.1ns ± 0%   +1.58%  (p=0.016 n=5+4)
IndexAnyASCII/16:8-8         111ns ± 0%   111ns ± 0%     ~     (all equal)
IndexAnyASCII/16:16-8        139ns ± 0%   144ns ± 0%   +3.60%  (p=0.016 n=4+5)
IndexAnyASCII/16:32-8        196ns ± 0%   207ns ± 0%   +5.61%  (p=0.016 n=5+4)
IndexAnyASCII/16:64-8        311ns ± 0%   320ns ± 0%   +2.89%  (p=0.016 n=4+5)
IndexAnyASCII/256:1-8        674ns ± 0%    65ns ± 1%  -90.35%  (p=0.008 n=5+5)
IndexAnyASCII/256:2-8        680ns ± 0%   680ns ± 0%     ~     (p=0.444 n=5+5)
IndexAnyASCII/256:4-8        686ns ± 0%   687ns ± 0%     ~     (p=0.167 n=5+5)
IndexAnyASCII/256:8-8        713ns ± 0%   712ns ± 0%   -0.14%  (p=0.008 n=5+5)
IndexAnyASCII/256:16-8       740ns ± 0%   744ns ± 0%   +0.54%  (p=0.016 n=5+4)
IndexAnyASCII/256:32-8       797ns ± 0%   808ns ± 0%   +1.43%  (p=0.008 n=5+5)
IndexAnyASCII/256:64-8       912ns ± 0%   921ns ± 0%   +0.99%  (p=0.016 n=4+5)
IndexAnyUTF8/1:1-8          27.5ns ± 0%  26.5ns ± 0%   -3.64%  (p=0.008 n=5+5)
IndexAnyUTF8/1:2-8          44.5ns ± 0%  26.5ns ± 0%  -40.50%  (p=0.008 n=5+5)
IndexAnyUTF8/1:4-8          45.6ns ± 0%  26.5ns ± 0%  -41.89%  (p=0.000 n=5+4)
IndexAnyUTF8/1:8-8          85.8ns ± 1%  26.5ns ± 0%  -69.11%  (p=0.008 n=5+5)
IndexAnyUTF8/1:16-8          110ns ± 1%    26ns ± 0%  -76.00%  (p=0.016 n=5+4)
IndexAnyUTF8/1:32-8          188ns ± 0%    30ns ± 0%  -84.04%  (p=0.008 n=5+5)
IndexAnyUTF8/1:64-8          333ns ± 0%    33ns ± 0%  -90.20%  (p=0.008 n=5+5)
IndexAnyUTF8/16:1-8          294ns ± 0%   235ns ± 0%  -20.07%  (p=0.008 n=5+5)
IndexAnyUTF8/16:2-8          563ns ± 0%   309ns ± 0%  -45.12%  (p=0.008 n=5+5)
IndexAnyUTF8/16:4-8          558ns ± 1%   309ns ± 0%  -44.60%  (p=0.000 n=5+4)
IndexAnyUTF8/16:8-8         1.23µs ± 0%  0.31µs ± 0%  -74.79%  (p=0.008 n=5+5)
IndexAnyUTF8/16:16-8        1.62µs ± 2%  0.31µs ± 0%  -80.93%  (p=0.008 n=5+5)
IndexAnyUTF8/16:32-8        2.86µs ± 0%  0.38µs ± 0%  -86.87%  (p=0.008 n=5+5)
IndexAnyUTF8/16:64-8        5.18µs ± 0%  0.42µs ± 0%  -91.86%  (p=0.008 n=5+5)
IndexAnyUTF8/256:1-8        4.27µs ± 1%  3.30µs ± 1%  -22.75%  (p=0.008 n=5+5)
IndexAnyUTF8/256:2-8        8.61µs ± 0%  4.45µs ± 0%  -48.31%  (p=0.016 n=4+5)
IndexAnyUTF8/256:4-8        8.44µs ± 0%  4.45µs ± 0%  -47.23%  (p=0.008 n=5+5)
IndexAnyUTF8/256:8-8        19.2µs ± 0%   4.5µs ± 0%  -76.78%  (p=0.008 n=5+5)
IndexAnyUTF8/256:16-8       25.6µs ± 0%   4.5µs ± 0%  -82.63%  (p=0.008 n=5+5)
IndexAnyUTF8/256:32-8       45.4µs ± 0%   5.5µs ± 0%  -87.85%  (p=0.016 n=4+5)
IndexAnyUTF8/256:64-8       82.5µs ± 0%   6.2µs ± 0%  -92.49%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:1-8     23.0ns ± 0%  26.5ns ± 0%  +15.02%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:2-8     24.5ns ± 0%  26.5ns ± 0%   +8.16%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:4-8     27.8ns ± 0%  26.5ns ± 0%   -4.68%  (p=0.029 n=4+4)
LastIndexAnyASCII/1:8-8     45.1ns ± 1%  26.5ns ± 0%  -41.29%  (p=0.000 n=5+4)
LastIndexAnyASCII/1:16-8    57.1ns ± 0%  26.5ns ± 0%  -53.61%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:32-8    81.5ns ± 0%  30.0ns ± 0%     ~     (p=0.079 n=4+5)
LastIndexAnyASCII/1:64-8     129ns ± 0%    32ns ± 0%  -74.81%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:1-8    72.6ns ± 0%  72.1ns ± 0%   -0.63%  (p=0.000 n=4+5)
LastIndexAnyASCII/16:2-8    77.2ns ± 0%  77.2ns ± 0%     ~     (p=0.167 n=5+5)
LastIndexAnyASCII/16:4-8    83.1ns ± 0%  83.2ns ± 0%     ~     (p=0.444 n=5+5)
LastIndexAnyASCII/16:8-8     109ns ± 1%   108ns ± 0%     ~     (p=0.167 n=5+5)
LastIndexAnyASCII/16:16-8    136ns ± 0%   136ns ± 0%     ~     (all equal)
LastIndexAnyASCII/16:32-8    195ns ± 0%   197ns ± 0%   +0.82%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:64-8    309ns ± 0%   309ns ± 0%     ~     (all equal)
LastIndexAnyASCII/256:1-8    653ns ± 0%   657ns ± 0%   +0.61%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:2-8    659ns ± 0%   658ns ± 0%     ~     (p=0.167 n=5+5)
LastIndexAnyASCII/256:4-8    664ns ± 0%   663ns ± 0%     ~     (p=0.095 n=5+4)
LastIndexAnyASCII/256:8-8    698ns ± 0%   689ns ± 0%   -1.29%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:16-8   726ns ± 0%   717ns ± 0%   -1.24%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:32-8   777ns ± 0%   779ns ± 0%     ~     (p=0.079 n=5+4)
LastIndexAnyASCII/256:64-8   889ns ± 0%   890ns ± 0%     ~     (p=0.444 n=5+5)
LastIndexAnyUTF8/1:1-8      32.1ns ± 0%  26.5ns ± 0%  -17.45%  (p=0.000 n=5+4)
LastIndexAnyUTF8/1:2-8      48.6ns ± 0%  26.5ns ± 0%  -45.52%  (p=0.000 n=5+4)
LastIndexAnyUTF8/1:4-8      49.6ns ± 0%  26.5ns ± 0%  -46.62%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:8-8      91.9ns ± 0%  26.5ns ± 0%  -71.18%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:16-8      114ns ± 1%    26ns ± 0%  -76.84%  (p=0.000 n=5+4)
LastIndexAnyUTF8/1:32-8      203ns ± 6%    30ns ± 0%  -85.25%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:64-8      330ns ± 0%    33ns ± 0%  -90.14%  (p=0.000 n=4+5)
LastIndexAnyUTF8/16:1-8      365ns ± 0%   164ns ± 0%  -55.04%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:2-8      638ns ± 0%   296ns ± 0%  -53.58%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:4-8      634ns ± 0%   296ns ± 0%  -53.31%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:8-8     1.30µs ± 0%  0.30µs ± 0%  -77.18%  (p=0.000 n=4+5)
LastIndexAnyUTF8/16:16-8    1.66µs ± 0%  0.30µs ± 0%  -82.19%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:32-8    2.90µs ± 0%  0.38µs ± 0%  -87.00%  (p=0.029 n=4+4)
LastIndexAnyUTF8/16:64-8    5.10µs ± 0%  0.42µs ± 0%  -91.78%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:1-8    5.42µs ± 0%  2.12µs ± 0%  -60.92%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:2-8    9.79µs ± 0%  4.26µs ± 0%  -56.47%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:4-8    9.66µs ± 0%  4.26µs ± 0%  -55.87%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:8-8    20.4µs ± 0%   4.3µs ± 0%  -79.10%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:16-8   26.0µs ± 1%   4.3µs ± 0%  -83.62%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:32-8   46.0µs ± 0%   5.5µs ± 0%  -88.09%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:64-8   81.1µs ± 0%   6.2µs ± 0%  -92.38%  (p=0.008 n=5+5)

name                         old time/op  new time/op   delta
pkg:strings goos:linux goarch:amd64
IndexAnyASCII/1:1-48         10.0ns ± 0%   13.3ns ± 0%  +33.00%  (p=0.008 n=5+5)
IndexAnyASCII/1:2-48         11.0ns ± 0%   15.5ns ± 0%  +40.55%  (p=0.016 n=4+5)
IndexAnyASCII/1:4-48         12.9ns ± 0%   15.4ns ± 0%  +19.69%  (p=0.008 n=5+5)
IndexAnyASCII/1:8-48         18.6ns ± 0%   15.5ns ± 0%  -16.45%  (p=0.000 n=4+5)
IndexAnyASCII/1:16-48        30.1ns ± 0%   16.9ns ± 0%     ~     (p=0.079 n=4+5)
IndexAnyASCII/1:32-48        53.1ns ± 0%   18.6ns ± 0%  -64.95%  (p=0.000 n=5+4)
IndexAnyASCII/1:64-48        98.9ns ± 0%   17.4ns ± 0%  -82.41%  (p=0.000 n=5+4)
IndexAnyASCII/16:1-48        35.0ns ± 0%   14.2ns ± 0%  -59.47%  (p=0.000 n=5+4)
IndexAnyASCII/16:2-48        35.5ns ± 0%   35.6ns ± 0%     ~     (p=0.238 n=5+4)
IndexAnyASCII/16:4-48        40.8ns ± 0%   40.7ns ± 1%     ~     (p=0.643 n=5+5)
IndexAnyASCII/16:8-48        50.8ns ± 0%   50.9ns ± 1%     ~     (p=1.000 n=4+5)
IndexAnyASCII/16:16-48       64.0ns ± 1%   64.5ns ± 1%     ~     (p=0.071 n=5+5)
IndexAnyASCII/16:32-48       98.3ns ± 0%  100.8ns ± 1%   +2.52%  (p=0.008 n=5+5)
IndexAnyASCII/16:64-48        156ns ± 0%    157ns ± 0%     ~     (p=0.238 n=4+5)
IndexAnyASCII/256:1-48        299ns ± 0%     24ns ± 3%  -92.12%  (p=0.008 n=5+5)
IndexAnyASCII/256:2-48        303ns ± 0%    304ns ± 0%     ~     (p=0.762 n=5+5)
IndexAnyASCII/256:4-48        311ns ± 0%    311ns ± 0%     ~     (p=0.476 n=5+5)
IndexAnyASCII/256:8-48        321ns ± 0%    321ns ± 0%     ~     (p=0.429 n=4+5)
IndexAnyASCII/256:16-48       334ns ± 0%    335ns ± 0%     ~     (p=0.079 n=5+4)
IndexAnyASCII/256:32-48       367ns ± 0%    365ns ± 0%     ~     (p=0.079 n=4+5)
IndexAnyASCII/256:64-48       431ns ± 1%    421ns ± 0%   -2.27%  (p=0.008 n=5+5)
IndexAnyUTF8/1:1-48          17.2ns ± 0%   10.8ns ± 0%  -37.21%  (p=0.029 n=4+4)
IndexAnyUTF8/1:2-48          26.7ns ± 0%   15.6ns ± 0%     ~     (p=0.079 n=4+5)
IndexAnyUTF8/1:4-48          28.2ns ± 0%   15.6ns ± 0%  -44.68%  (p=0.000 n=5+4)
IndexAnyUTF8/1:8-48          48.8ns ± 0%   15.6ns ± 0%  -68.03%  (p=0.029 n=4+4)
IndexAnyUTF8/1:16-48         58.3ns ± 0%   16.2ns ± 0%     ~     (p=0.079 n=4+5)
IndexAnyUTF8/1:32-48          103ns ± 0%     18ns ± 0%  -82.27%  (p=0.008 n=5+5)
IndexAnyUTF8/1:64-48          182ns ± 0%     17ns ± 0%  -90.53%  (p=0.008 n=5+5)
IndexAnyUTF8/16:1-48          197ns ± 0%     25ns ± 0%  -87.34%  (p=0.000 n=5+4)
IndexAnyUTF8/16:2-48          348ns ± 0%    163ns ± 0%  -53.11%  (p=0.000 n=5+4)
IndexAnyUTF8/16:4-48          374ns ± 0%    163ns ± 0%  -56.37%  (p=0.000 n=5+4)
IndexAnyUTF8/16:8-48          716ns ± 0%    163ns ± 0%  -77.22%  (p=0.000 n=5+4)
IndexAnyUTF8/16:16-48         859ns ± 0%    175ns ± 0%  -79.63%  (p=0.000 n=5+4)
IndexAnyUTF8/16:32-48        1.58µs ± 0%   0.20µs ± 0%  -87.01%  (p=0.029 n=4+4)
IndexAnyUTF8/16:64-48        2.84µs ± 0%   0.19µs ± 1%  -93.34%  (p=0.008 n=5+5)
IndexAnyUTF8/256:1-48        2.61µs ± 0%   0.27µs ± 0%  -89.81%  (p=0.008 n=5+5)
IndexAnyUTF8/256:2-48        4.95µs ± 0%   2.23µs ± 0%  -54.91%  (p=0.016 n=5+4)
IndexAnyUTF8/256:4-48        5.55µs ± 0%   2.23µs ± 0%  -59.72%  (p=0.008 n=5+5)
IndexAnyUTF8/256:8-48        10.8µs ± 0%    2.2µs ± 0%  -79.39%  (p=0.008 n=5+5)
IndexAnyUTF8/256:16-48       13.1µs ± 0%    2.5µs ± 0%  -81.21%  (p=0.016 n=4+5)
IndexAnyUTF8/256:32-48       24.7µs ± 0%    2.8µs ± 0%  -88.49%  (p=0.008 n=5+5)
IndexAnyUTF8/256:64-48       45.0µs ± 0%    2.6µs ± 1%  -94.23%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:1-48     13.9ns ± 0%   15.2ns ± 0%   +9.35%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:2-48     14.4ns ± 0%   15.2ns ± 0%   +5.56%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:4-48     16.7ns ± 0%   15.2ns ± 0%   -8.98%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:8-48     24.0ns ± 0%   15.2ns ± 0%  -36.67%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:16-48    35.6ns ± 0%   15.0ns ± 0%  -57.82%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:32-48    68.9ns ± 0%   16.7ns ± 0%  -75.75%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:64-48     104ns ± 0%     17ns ± 1%  -83.81%  (p=0.008 n=5+5)
LastIndexAnyASCII/16:1-48    35.0ns ± 0%   35.0ns ± 0%     ~     (all equal)
LastIndexAnyASCII/16:2-48    35.6ns ± 0%   35.6ns ± 0%     ~     (all equal)
LastIndexAnyASCII/16:4-48    41.0ns ± 0%   40.8ns ± 0%   -0.49%  (p=0.032 n=5+5)
LastIndexAnyASCII/16:8-48    50.9ns ± 0%   50.7ns ± 1%     ~     (p=0.397 n=5+5)
LastIndexAnyASCII/16:16-48   64.3ns ± 1%   64.4ns ± 1%     ~     (p=1.000 n=4+5)
LastIndexAnyASCII/16:32-48    100ns ± 0%    100ns ± 0%   +0.38%  (p=0.016 n=4+5)
LastIndexAnyASCII/16:64-48    157ns ± 1%    163ns ± 0%   +3.82%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:1-48    302ns ± 0%    300ns ± 0%   -0.53%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:2-48    305ns ± 0%    303ns ± 0%   -0.66%  (p=0.000 n=5+4)
LastIndexAnyASCII/256:4-48    313ns ± 0%    307ns ± 0%   -2.04%  (p=0.000 n=4+5)
LastIndexAnyASCII/256:8-48    323ns ± 0%    315ns ± 0%   -2.48%  (p=0.029 n=4+4)
LastIndexAnyASCII/256:16-48   333ns ± 0%    332ns ± 0%   -0.30%  (p=0.048 n=5+5)
LastIndexAnyASCII/256:32-48   366ns ± 0%    367ns ± 0%     ~     (p=0.238 n=4+5)
LastIndexAnyASCII/256:64-48   430ns ± 0%    430ns ± 0%     ~     (p=1.000 n=5+5)
LastIndexAnyUTF8/1:1-48      21.1ns ± 0%   13.9ns ± 0%  -34.00%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:2-48      29.5ns ± 0%   13.9ns ± 0%  -52.95%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:4-48      31.6ns ± 0%   13.9ns ± 0%  -55.96%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:8-48      51.1ns ± 0%   13.9ns ± 0%  -72.81%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:16-48     58.9ns ± 0%   14.6ns ± 0%  -75.23%  (p=0.016 n=5+4)
LastIndexAnyUTF8/1:32-48      103ns ± 0%     16ns ± 1%  -84.12%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:64-48      177ns ± 0%     17ns ± 1%  -90.62%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:1-48      275ns ± 1%    105ns ± 0%  -61.85%  (p=0.000 n=5+4)
LastIndexAnyUTF8/16:2-48      406ns ± 0%    216ns ± 0%  -46.70%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:4-48      458ns ± 0%    216ns ± 0%  -52.75%  (p=0.000 n=4+5)
LastIndexAnyUTF8/16:8-48      753ns ± 0%    216ns ± 0%  -71.31%  (p=0.029 n=4+4)
LastIndexAnyUTF8/16:16-48     902ns ± 0%    221ns ± 0%  -75.50%  (p=0.016 n=5+4)
LastIndexAnyUTF8/16:32-48    1.57µs ± 0%   0.24µs ± 0%  -84.46%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:64-48    2.77µs ± 0%   0.24µs ± 0%  -91.22%  (p=0.000 n=5+4)
LastIndexAnyUTF8/256:1-48    4.06µs ± 0%   1.53µs ± 0%  -62.26%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:2-48    5.92µs ± 0%   3.04µs ± 0%  -48.55%  (p=0.016 n=4+5)
LastIndexAnyUTF8/256:4-48    6.82µs ± 0%   3.04µs ± 0%  -55.34%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:8-48    11.5µs ± 0%    3.0µs ± 0%  -73.48%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:16-48   14.1µs ± 0%    3.1µs ± 0%  -77.85%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:32-48   24.5µs ± 0%    3.5µs ± 0%  -85.85%  (p=0.016 n=5+4)
LastIndexAnyUTF8/256:64-48   44.0µs ± 0%    3.5µs ± 0%  -92.12%  (p=0.008 n=5+5)
pkg:bytes goos:linux goarch:amd64
IndexAnyASCII/1:1-48         9.56ns ± 0%  11.00ns ± 0%  +15.06%  (p=0.016 n=5+4)
IndexAnyASCII/1:2-48         11.0ns ± 0%   10.8ns ± 2%   -1.64%  (p=0.048 n=5+5)
IndexAnyASCII/1:4-48         13.9ns ± 0%   11.0ns ± 1%  -21.15%  (p=0.008 n=5+5)
IndexAnyASCII/1:8-48         19.6ns ± 0%   10.8ns ± 3%  -44.90%  (p=0.008 n=5+5)
IndexAnyASCII/1:16-48        31.1ns ± 0%   11.5ns ± 0%  -63.02%  (p=0.008 n=5+5)
IndexAnyASCII/1:32-48        54.0ns ± 0%   11.8ns ± 0%  -78.15%  (p=0.000 n=5+4)
IndexAnyASCII/1:64-48         100ns ± 0%     13ns ± 0%  -86.89%  (p=0.008 n=5+5)
IndexAnyASCII/16:1-48        35.5ns ± 0%   14.8ns ± 0%  -58.26%  (p=0.008 n=5+5)
IndexAnyASCII/16:2-48        36.2ns ± 1%   36.0ns ± 1%     ~     (p=0.087 n=5+5)
IndexAnyASCII/16:4-48        40.3ns ± 1%   39.7ns ± 4%     ~     (p=0.175 n=4+5)
IndexAnyASCII/16:8-48        48.7ns ± 5%   45.8ns ± 0%   -6.02%  (p=0.016 n=5+4)
IndexAnyASCII/16:16-48       64.1ns ±11%   62.1ns ± 1%     ~     (p=0.143 n=5+5)
IndexAnyASCII/16:32-48       97.9ns ± 1%   98.3ns ± 1%     ~     (p=0.294 n=5+5)
IndexAnyASCII/16:64-48        163ns ± 0%    157ns ± 0%   -3.68%  (p=0.008 n=5+5)
IndexAnyASCII/256:1-48        389ns ± 0%     25ns ± 0%  -93.65%  (p=0.000 n=5+4)
IndexAnyASCII/256:2-48        391ns ± 0%    307ns ± 0%  -21.48%  (p=0.000 n=5+4)
IndexAnyASCII/256:4-48        394ns ± 0%    323ns ± 0%  -17.92%  (p=0.008 n=5+5)
IndexAnyASCII/256:8-48        402ns ± 0%    323ns ± 0%  -19.51%  (p=0.008 n=5+5)
IndexAnyASCII/256:16-48       414ns ± 0%    334ns ± 0%  -19.32%  (p=0.016 n=4+5)
IndexAnyASCII/256:32-48       446ns ± 0%    367ns ± 0%  -17.75%  (p=0.016 n=5+4)
IndexAnyASCII/256:64-48       511ns ± 0%    424ns ± 0%  -17.02%  (p=0.008 n=5+5)
IndexAnyUTF8/1:1-48          17.4ns ± 0%   11.0ns ± 0%  -36.64%  (p=0.008 n=5+5)
IndexAnyUTF8/1:2-48          27.3ns ± 1%   11.0ns ± 0%  -59.74%  (p=0.008 n=5+5)
IndexAnyUTF8/1:4-48          28.7ns ± 0%   11.0ns ± 0%  -61.73%  (p=0.008 n=5+5)
IndexAnyUTF8/1:8-48          49.2ns ± 0%   11.0ns ± 0%  -77.66%  (p=0.008 n=5+5)
IndexAnyUTF8/1:16-48         56.0ns ± 0%   11.5ns ± 0%  -79.46%  (p=0.000 n=5+4)
IndexAnyUTF8/1:32-48          102ns ± 0%     12ns ± 0%  -88.24%  (p=0.008 n=5+5)
IndexAnyUTF8/1:64-48          177ns ± 0%     13ns ± 0%  -92.51%  (p=0.008 n=5+5)
IndexAnyUTF8/16:1-48          212ns ± 0%    112ns ± 0%  -47.17%  (p=0.008 n=5+5)
IndexAnyUTF8/16:2-48          356ns ± 0%    159ns ± 1%  -55.28%  (p=0.000 n=4+5)
IndexAnyUTF8/16:4-48          372ns ± 0%    158ns ± 0%  -57.47%  (p=0.008 n=5+5)
IndexAnyUTF8/16:8-48          712ns ± 0%    159ns ± 1%  -77.70%  (p=0.008 n=5+5)
IndexAnyUTF8/16:16-48         829ns ± 0%    129ns ± 0%  -84.44%  (p=0.008 n=5+5)
IndexAnyUTF8/16:32-48        1.55µs ± 0%   0.16µs ± 0%  -89.87%  (p=0.008 n=5+5)
IndexAnyUTF8/16:64-48        2.77µs ± 0%   0.14µs ± 0%  -94.94%  (p=0.008 n=5+5)
IndexAnyUTF8/256:1-48        2.85µs ± 0%   1.63µs ± 1%  -42.74%  (p=0.008 n=5+5)
IndexAnyUTF8/256:2-48        5.14µs ± 1%   2.03µs ± 0%  -60.51%  (p=0.008 n=5+5)
IndexAnyUTF8/256:4-48        5.56µs ± 0%   2.03µs ± 0%  -63.52%  (p=0.008 n=5+5)
IndexAnyUTF8/256:8-48        10.8µs ± 0%    2.0µs ± 0%  -81.22%  (p=0.008 n=5+5)
IndexAnyUTF8/256:16-48       12.9µs ± 0%    1.9µs ± 0%  -85.55%  (p=0.008 n=5+5)
IndexAnyUTF8/256:32-48       24.2µs ± 0%    2.1µs ± 0%  -91.29%  (p=0.016 n=5+4)
IndexAnyUTF8/256:64-48       43.7µs ± 0%    2.0µs ± 0%  -95.32%  (p=0.016 n=5+4)
LastIndexAnyASCII/1:1-48     13.7ns ± 1%   12.8ns ± 0%   -6.57%  (p=0.016 n=5+4)
LastIndexAnyASCII/1:2-48     14.7ns ± 0%   12.7ns ± 1%  -13.33%  (p=0.000 n=4+5)
LastIndexAnyASCII/1:4-48     16.9ns ± 0%   12.7ns ± 1%  -24.73%  (p=0.000 n=4+5)
LastIndexAnyASCII/1:8-48     20.5ns ± 0%   12.7ns ± 0%  -37.85%  (p=0.000 n=4+5)
LastIndexAnyASCII/1:16-48    28.0ns ± 0%   11.7ns ± 0%     ~     (p=0.079 n=4+5)
LastIndexAnyASCII/1:32-48    69.8ns ± 0%   12.4ns ± 0%  -82.19%  (p=0.008 n=5+5)
LastIndexAnyASCII/1:64-48    73.8ns ± 0%   13.3ns ± 0%  -82.03%  (p=0.000 n=4+5)
LastIndexAnyASCII/16:1-48    35.5ns ± 0%   35.5ns ± 0%     ~     (all equal)
LastIndexAnyASCII/16:2-48    36.0ns ± 0%   36.1ns ± 0%   +0.28%  (p=0.016 n=4+5)
LastIndexAnyASCII/16:4-48    40.3ns ± 2%   40.0ns ± 6%     ~     (p=0.651 n=5+5)
LastIndexAnyASCII/16:8-48    50.3ns ± 0%   50.2ns ± 9%     ~     (p=0.175 n=4+5)
LastIndexAnyASCII/16:16-48   62.4ns ± 4%   64.4ns ± 0%   +3.28%  (p=0.016 n=5+4)
LastIndexAnyASCII/16:32-48   98.9ns ± 0%   98.4ns ± 0%   -0.53%  (p=0.016 n=5+4)
LastIndexAnyASCII/16:64-48    160ns ± 1%    161ns ± 1%     ~     (p=0.325 n=5+5)
LastIndexAnyASCII/256:1-48    300ns ± 0%    301ns ± 0%   +0.33%  (p=0.008 n=5+5)
LastIndexAnyASCII/256:2-48    304ns ± 0%    304ns ± 0%     ~     (p=1.000 n=5+5)
LastIndexAnyASCII/256:4-48    311ns ± 0%    311ns ± 0%     ~     (p=0.556 n=4+5)
LastIndexAnyASCII/256:8-48    320ns ± 0%    321ns ± 0%     ~     (p=0.143 n=5+5)
LastIndexAnyASCII/256:16-48   333ns ± 0%    335ns ± 0%   +0.60%  (p=0.029 n=4+4)
LastIndexAnyASCII/256:32-48   367ns ± 0%    366ns ± 0%     ~     (p=0.095 n=4+5)
LastIndexAnyASCII/256:64-48   431ns ± 0%    424ns ± 0%   -1.62%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:1-48      19.7ns ± 1%   11.9ns ± 0%  -39.47%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:2-48      27.6ns ± 1%   11.9ns ± 0%  -56.82%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:4-48      29.9ns ± 0%   11.9ns ± 0%     ~     (p=0.079 n=4+5)
LastIndexAnyUTF8/1:8-48      48.7ns ± 0%   11.9ns ± 0%  -75.54%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:16-48     57.8ns ± 0%   11.4ns ± 0%  -80.26%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:32-48     94.7ns ± 0%   12.2ns ± 0%  -87.07%  (p=0.008 n=5+5)
LastIndexAnyUTF8/1:64-48      163ns ± 0%     13ns ± 1%  -91.93%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:1-48      258ns ± 0%     88ns ± 0%  -65.76%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:2-48      400ns ± 0%    162ns ± 0%  -59.38%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:4-48      415ns ± 0%    162ns ± 0%  -60.87%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:8-48      737ns ± 0%    162ns ± 0%  -78.02%  (p=0.000 n=5+4)
LastIndexAnyUTF8/16:16-48     882ns ± 0%    128ns ± 0%  -85.49%  (p=0.008 n=5+5)
LastIndexAnyUTF8/16:32-48    1.47µs ± 0%   0.16µs ± 0%  -89.29%  (p=0.000 n=4+5)
LastIndexAnyUTF8/16:64-48    2.56µs ± 0%   0.14µs ± 0%  -94.41%  (p=0.016 n=5+4)
LastIndexAnyUTF8/256:1-48    3.60µs ± 0%   1.23µs ± 0%  -65.67%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:2-48    5.78µs ± 0%   2.18µs ± 0%  -62.32%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:4-48    6.26µs ± 0%   2.18µs ± 0%  -65.15%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:8-48    11.2µs ± 0%    2.2µs ± 0%  -80.53%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:16-48   13.5µs ± 0%    1.9µs ± 0%  -86.02%  (p=0.016 n=4+5)
LastIndexAnyUTF8/256:32-48   23.0µs ± 0%    2.1µs ± 0%  -90.72%  (p=0.008 n=5+5)
LastIndexAnyUTF8/256:64-48   40.5µs ± 0%    2.1µs ± 0%  -94.73%  (p=0.008 n=5+5)

Change-Id: Ie05e306f8b184b989701868cb161ce8b3f18203b
Reviewed-on: https://go-review.googlesource.com/c/go/+/156998
Run-TryBot: eric fang <eric.fang@arm.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-03-11 05:13:13 +00:00
erifan01
18a6fd44bb bytes, strings: moves indexRabinKarp function to internal/bytealg
In order to facilitate optimization of IndexAny and LastIndexAny, this patch moves
three Rabin-Karp related functions indexRabinKarp, hashStr and hashStrRev in strings
package to initernal/bytealg. There are also three functions in the bytes package with
the same names and functions but different parameter types. To highlight this, this
patch also moves them to internal/bytealg and gives them slightly different names.

Related benchmark changes on amd64 and arm64:

name          old time/op    new time/op    delta
pkg:strings goos:linux goarch:amd64
Index-16        14.0ns ± 1%    14.1ns ± 2%    ~     (p=0.738 n=5+5)
LastIndex-16    15.5ns ± 1%    15.7ns ± 4%    ~     (p=0.897 n=5+5)
pkg:bytes goos:linux goarch:amd64
Index/10-16     26.5ns ± 1%    26.5ns ± 0%    ~     (p=0.873 n=5+5)
Index/32-16     26.2ns ± 0%    25.7ns ± 0%  -1.68%  (p=0.008 n=5+5)
Index/4K-16     5.12µs ± 4%    5.14µs ± 2%    ~     (p=0.841 n=5+5)
Index/4M-16     5.44ms ± 3%    5.34ms ± 2%    ~     (p=0.056 n=5+5)
Index/64M-16    85.8ms ± 3%    84.6ms ± 0%  -1.37%  (p=0.016 n=5+5)

name          old speed      new speed      delta
pkg:bytes goos:linux goarch:amd64
Index/10-16    377MB/s ± 1%   377MB/s ± 0%    ~     (p=1.000 n=5+5)
Index/32-16   1.22GB/s ± 1%  1.24GB/s ± 0%  +1.66%  (p=0.008 n=5+5)
Index/4K-16    800MB/s ± 4%   797MB/s ± 2%    ~     (p=0.841 n=5+5)
Index/4M-16    771MB/s ± 3%   786MB/s ± 2%    ~     (p=0.056 n=5+5)
Index/64M-16   783MB/s ± 3%   793MB/s ± 0%  +1.36%  (p=0.016 n=5+5)

name         old time/op   new time/op   delta
pkg:strings goos:linux goarch:arm64
Index-8       22.6ns ± 0%   22.5ns ± 0%    ~     (p=0.167 n=5+5)
LastIndex-8   17.5ns ± 0%   17.5ns ± 0%    ~     (all equal)
pkg:bytes goos:linux goarch:arm64
Index/10-8    25.0ns ± 0%   25.0ns ± 0%    ~     (all equal)
Index/32-8     160ns ± 0%    160ns ± 0%    ~     (all equal)
Index/4K-8    6.26µs ± 0%   6.26µs ± 0%    ~     (p=0.167 n=5+5)
Index/4M-8    6.30ms ± 0%   6.31ms ± 0%    ~     (p=1.000 n=5+5)
Index/64M-8    101ms ± 0%    101ms ± 0%    ~     (p=0.690 n=5+5)

name         old speed     new speed     delta
pkg:bytes goos:linux goarch:arm64
Index/10-8   399MB/s ± 0%  400MB/s ± 0%  +0.08%  (p=0.008 n=5+5)
Index/32-8   200MB/s ± 0%  200MB/s ± 0%    ~     (p=0.127 n=4+5)
Index/4K-8   654MB/s ± 0%  654MB/s ± 0%  +0.01%  (p=0.016 n=5+5)
Index/4M-8   665MB/s ± 0%  665MB/s ± 0%    ~     (p=0.833 n=5+5)
Index/64M-8  665MB/s ± 0%  665MB/s ± 0%    ~     (p=0.913 n=5+5)

Change-Id: Icce3bc162bb8613ac36dc963a46c51f8e82ab842
Reviewed-on: https://go-review.googlesource.com/c/go/+/208638
Run-TryBot: eric fang <eric.fang@arm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-03-04 17:36:05 +00:00
Martin Möhrmann
3259bc4419 strings, bytes: add ToValidUTF8
The newly added functions create a copy of their input with all bytes in
invalid UTF-8 byte sequences mapped to the UTF-8 byte sequence
given as replacement parameter.

Fixes #25805

Change-Id: Iaf65f65b40c0581c6bb000f1590408d6628321d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/142003
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-01 18:31:47 +00:00
Josh Bleecher Snyder
ca0c449a6b bytes, internal/bytealg: simplify Equal
The compiler has advanced enough that it is cheaper
to convert to strings than to go through the assembly
trampolines to call runtime.memequal.

Simplify Equal accordingly, and cull dead code from bytealg.

While we're here, simplify Equal's documentation.

Fixes #31587

Change-Id: Ie721d33f9a6cbd86b1d873398b20e7882c2c63e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/173323
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-24 00:56:36 +00:00
Tobias Klauser
08e1823a63 bytes: optimize ToLower and ToUpper for ASCII-only case
Follow what CL 68370 and CL 76470 did for the respective functions in
package strings.

Also adjust godoc strings to match the respective strings functions and
mention the special case for ASCII-only byte slices which don't need
conversion.

name                                       old time/op  new time/op  delta
ToUpper/#00-8                              9.35ns ± 3%  6.08ns ± 2%  -35.04%  (p=0.000 n=9+9)
ToUpper/ONLYUPPER-8                        77.7ns ± 1%  16.9ns ± 2%  -78.22%  (p=0.000 n=10+10)
ToUpper/abc-8                              36.5ns ± 1%  22.1ns ± 1%  -39.43%  (p=0.000 n=10+8)
ToUpper/AbC123-8                           56.9ns ± 2%  28.2ns ± 2%  -50.54%  (p=0.000 n=8+10)
ToUpper/azAZ09_-8                          62.3ns ± 1%  26.9ns ± 1%  -56.82%  (p=0.000 n=9+10)
ToUpper/longStrinGwitHmixofsmaLLandcAps-8   219ns ± 2%    63ns ± 2%  -71.17%  (p=0.000 n=10+10)
ToUpper/longɐstringɐwithɐnonasciiⱯchars-8   367ns ± 2%   374ns ± 3%   +2.05%  (p=0.000 n=9+10)
ToUpper/ɐɐɐɐɐ-8                             200ns ± 1%   206ns ± 1%   +2.49%  (p=0.000 n=10+10)
ToUpper/a\u0080\U0010ffff-8                90.4ns ± 1%  93.8ns ± 0%   +3.82%  (p=0.000 n=10+7)
ToLower/#00-8                              9.59ns ± 1%  6.13ns ± 2%  -36.08%  (p=0.000 n=10+10)
ToLower/abc-8                              36.4ns ± 1%  10.4ns ± 1%  -71.50%  (p=0.000 n=10+10)
ToLower/AbC123-8                           55.8ns ± 1%  27.5ns ± 1%  -50.61%  (p=0.000 n=10+10)
ToLower/azAZ09_-8                          61.7ns ± 1%  30.2ns ± 1%  -50.98%  (p=0.000 n=8+10)
ToLower/longStrinGwitHmixofsmaLLandcAps-8   226ns ± 1%    64ns ± 1%  -71.53%  (p=0.000 n=10+9)
ToLower/LONGⱯSTRINGⱯWITHⱯNONASCIIⱯCHARS-8   354ns ± 0%   361ns ± 0%   +2.18%  (p=0.000 n=10+10)
ToLower/ⱭⱭⱭⱭⱭ-8                             180ns ± 1%   186ns ± 0%   +3.45%  (p=0.000 n=10+9)
ToLower/A\u0080\U0010ffff-8                91.7ns ± 0%  94.5ns ± 0%   +2.99%  (p=0.000 n=10+10)

Change-Id: Ifdb8ae328ff9feacd1c170db8eebbf98c399e204
Reviewed-on: https://go-review.googlesource.com/c/go/+/170954
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2019-04-09 05:45:34 +00:00
Tobias Klauser
94507d2213 bytes: merge explodetests into splittests
splittests already contains most of the tests that cover explode. Add
the missing ones and skip the append test for empty results which would
otherwise lead to an "index out of range" panic.

Change-Id: I2cb922282d2676be9ef85f186513075ae17c0243
Reviewed-on: https://go-review.googlesource.com/c/go/+/170126
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-03 14:46:01 +00:00
Ben Hoyt
154e5abfcd bytes, strings: add tests for TrimLeftFunc and TrimRightFunc
When I was working on the fix for #31038 (make TrimSpace return nil on
all-space input) I noticed that there were no tests for TrimLeftFunc
and TrimRightFunc, including the funky nil behavior. So add some!

I've just reused the existing TrimFunc test cases for TrimLeftFunc and
TrimRightFunc, as well as adding new tests for the empty string and
all-trimmed cases (which test the nil-returning behavior of TrimFunc and
TrimLeftFunc).

Change-Id: Ib580d4364e9b3c91350305f9d9873080d7862904
Reviewed-on: https://go-review.googlesource.com/c/go/+/170061
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-29 14:16:35 +00:00
Ben Hoyt
f24e1099cb bytes: make TrimSpace return nil on all-space input
Issue #29122 introduced a subtle regression due to the way that
TrimFuncLeft is written: previously TrimSpace returned nil when given
an input of all whitespace, but with the #29122 changes it returned an
empty slice on all-space input.

This change adds a special case to the new, optimized TrimSpace to go
back to that behavior. While it is odd behavior and people shouldn't be
relying on these functions returning a nil slice in practice, it's not
worth the breakage of code that does.

This tweak doesn't change the TrimSpace benchmarks significantly.

Fixes #31038

Change-Id: Idb495d02b474054d2b2f593c2e318a7a6625688a
Reviewed-on: https://go-review.googlesource.com/c/go/+/169518
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-27 13:52:52 +00:00
Tobias Klauser
9d9d4eeb87 bytes: add hard benchmarks for Index and Count
Add Benchmark(Index|Count)Hard[1-3] in preparation for implementing
Index and Count in assembly on arm.

Updates #29001

Change-Id: I2a9701892190e8d91de069c2f5a7f5bd3544c6c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/167798
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-15 14:04:37 +00:00
Ben Hoyt
4b4f222a0d bytes, strings: speed up TrimSpace 4-5x for common ASCII cases
This change adds a fast path for ASCII strings to both
strings.TrimSpace and bytes.TrimSpace. It doesn't slow down the
non-ASCII path much, if at all.

I added benchmarks for strings.TrimSpace as it didn't have any, and
I fleshed out the benchmarks for bytes.TrimSpace as it just had one
case (for ASCII). The benchmarks (and the code!) are now the same
between the two versions. Below are the benchmark results:

strings.TrimSpace:

name                      old time/op  new time/op  delta
TrimSpace/NoTrim-8        18.6ns ± 0%   3.8ns ± 0%  -79.53%  (p=0.000 n=5+4)
TrimSpace/ASCII-8         33.5ns ± 2%   6.0ns ± 3%  -82.05%  (p=0.008 n=5+5)
TrimSpace/SomeNonASCII-8  97.1ns ± 1%  88.6ns ± 1%   -8.68%  (p=0.008 n=5+5)
TrimSpace/JustNonASCII-8   144ns ± 0%   143ns ± 0%     ~     (p=0.079 n=4+5)

bytes.TrimSpace:

name                      old time/op  new time/op  delta
TrimSpace/NoTrim-8        18.9ns ± 1%   4.1ns ± 1%  -78.34%  (p=0.008 n=5+5)
TrimSpace/ASCII-8         29.9ns ± 0%   6.3ns ± 1%  -79.06%  (p=0.008 n=5+5)
TrimSpace/SomeNonASCII-8  91.5ns ± 0%  82.3ns ± 0%  -10.03%  (p=0.008 n=5+5)
TrimSpace/JustNonASCII-8   150ns ± 0%   150ns ± 0%     ~     (all equal)

Fixes #29122

Change-Id: Ica45cd86a219cadf60173ec9db260133cd1d7951
Reviewed-on: https://go-review.googlesource.com/c/go/+/152917
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-03-12 15:52:17 +00:00
Tobias Klauser
b4baa8dd1d bytes: add benchmark for LastIndex
Add BenchmarkLastIndexHard[1-3] in preparation for implementing
LastIndex using Rabin-Karp akin to strings.LastIndex

BenchmarkLastIndexHard1-8   	     500	   3162694 ns/op
BenchmarkLastIndexHard2-8   	     500	   3170475 ns/op
BenchmarkLastIndexHard3-8   	     500	   3051127 ns/op

Change-Id: Id99f85f9640e248958f2b4be4dfd8c974e3b50e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/166257
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-08 13:46:34 +00:00
Brad Fitzpatrick
ebdc0b8d68 bytes, strings: add ReplaceAll
Credit to Harald Nordgren for the proposal in
https://golang.org/cl/137456 and #27864.

Fixes #27864

Change-Id: I80546683b0623124fe4627a71af88add2f6c1c27
Reviewed-on: https://go-review.googlesource.com/137855
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-09-26 20:51:23 +00:00
Keith Randall
45964e4f9c internal/bytealg: move Count to bytealg
Move bytes.Count and strings.Count to bytealg.

Update #19792

Change-Id: I3e4e14b504a0b71758885bb131e5656e342cf8cb
Reviewed-on: https://go-review.googlesource.com/98495
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-04 17:49:25 +00:00
Keith Randall
a025277505 bytes,strings: in generic Index, use mix of IndexByte and Rabin-Karp
Use IndexByte first, as it allows us to skip lots of bytes quickly.
If IndexByte is generating a lot of false positives, switch over to Rabin-Karp.

Experiments for ppc64le
bytes:
name                             old time/op  new time/op  delta
IndexPeriodic/IndexPeriodic2-2   1.12ms ± 0%  0.18ms ± 0%  -83.54%  (p=0.000 n=10+9)
IndexPeriodic/IndexPeriodic4-2    635µs ± 0%   184µs ± 0%  -71.06%  (p=0.000 n=9+9)
IndexPeriodic/IndexPeriodic8-2    289µs ± 0%   184µs ± 0%  -36.51%  (p=0.000 n=10+9)
IndexPeriodic/IndexPeriodic16-2   133µs ± 0%   183µs ± 0%  +37.68%  (p=0.000 n=10+9)
IndexPeriodic/IndexPeriodic32-2  68.3µs ± 0%  70.2µs ± 0%   +2.76%  (p=0.000 n=10+10)
IndexPeriodic/IndexPeriodic64-2  35.8µs ± 0%  36.6µs ± 0%   +2.17%  (p=0.000 n=8+10)

strings:
name                             old time/op  new time/op  delta
IndexPeriodic/IndexPeriodic2-2    184µs ± 0%   184µs ± 0%   +0.11%  (p=0.029 n=4+4)
IndexPeriodic/IndexPeriodic4-2    184µs ± 0%   184µs ± 0%     ~     (p=0.886 n=4+4)
IndexPeriodic/IndexPeriodic8-2    184µs ± 0%   184µs ± 0%     ~     (p=0.486 n=4+4)
IndexPeriodic/IndexPeriodic16-2   185µs ± 1%   184µs ± 0%     ~     (p=0.343 n=4+4)
IndexPeriodic/IndexPeriodic32-2   184µs ± 0%    69µs ± 0%  -62.37%  (p=0.029 n=4+4)
IndexPeriodic/IndexPeriodic64-2   184µs ± 0%    37µs ± 0%  -80.17%  (p=0.029 n=4+4)

Fixes #22578

Change-Id: If2a4d8554cb96bfd699b58149d13ac294615f8b8
Reviewed-on: https://go-review.googlesource.com/76070
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
2017-11-15 17:35:09 +00:00
Ian Lance Taylor
a9e2479a44 bytes: set cap of slices returned by Split and Fields and friends
This avoids the problem in which appending to a slice returned by
Split can affect subsequent slices.

Fixes #21149.

Change-Id: Ie3df2b9ceeb9605d4625f47d49073c5f348cf0a1
Reviewed-on: https://go-review.googlesource.com/74510
Reviewed-by: Jelte Fennema <github-tech@jeltef.nl>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-11-03 19:06:15 +00:00
Martin Möhrmann
7df29b50b2 bytes: speed up Fields and FieldsFunc
Applies the optimizations from golang.org/cl/42810 and golang.org/cl/37959
done to the strings package to the bytes package.

name                      old time/op    new time/op     delta
Fields/ASCII/16              417ns ± 4%      118ns ± 3%    -71.65%  (p=0.000 n=10+10)
Fields/ASCII/256            5.95µs ± 3%     0.88µs ± 0%    -85.23%  (p=0.000 n=10+7)
Fields/ASCII/4096           92.3µs ± 1%     12.8µs ± 2%    -86.13%  (p=0.000 n=10+10)
Fields/ASCII/65536          1.49ms ± 1%     0.25ms ± 1%    -83.14%  (p=0.000 n=10+10)
Fields/ASCII/1048576        25.0ms ± 1%      6.5ms ± 2%    -74.04%  (p=0.000 n=10+10)
Fields/Mixed/16              406ns ± 1%      222ns ± 1%    -45.24%  (p=0.000 n=10+9)
Fields/Mixed/256            5.78µs ± 1%     2.27µs ± 1%    -60.73%  (p=0.000 n=9+10)
Fields/Mixed/4096           97.9µs ± 1%     40.5µs ± 3%    -58.66%  (p=0.000 n=10+10)
Fields/Mixed/65536          1.58ms ± 1%     0.69ms ± 1%    -56.58%  (p=0.000 n=10+10)
Fields/Mixed/1048576        26.6ms ± 1%     12.6ms ± 2%    -52.44%  (p=0.000 n=9+10)
FieldsFunc/ASCII/16          395ns ± 1%      188ns ± 1%    -52.34%  (p=0.000 n=10+10)
FieldsFunc/ASCII/256        5.90µs ± 1%     2.00µs ± 1%    -66.06%  (p=0.000 n=10+10)
FieldsFunc/ASCII/4096       92.5µs ± 1%     33.0µs ± 1%    -64.34%  (p=0.000 n=10+9)
FieldsFunc/ASCII/65536      1.48ms ± 1%     0.54ms ± 1%    -63.38%  (p=0.000 n=10+9)
FieldsFunc/ASCII/1048576    25.1ms ± 1%     10.5ms ± 3%    -58.24%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16          401ns ± 1%      205ns ± 2%    -48.87%  (p=0.000 n=10+10)
FieldsFunc/Mixed/256        5.70µs ± 1%     1.98µs ± 1%    -65.28%  (p=0.000 n=10+10)
FieldsFunc/Mixed/4096       97.5µs ± 1%     35.4µs ± 1%    -63.65%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536      1.57ms ± 1%     0.61ms ± 1%    -61.20%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576    26.5ms ± 1%     11.4ms ± 2%    -56.84%  (p=0.000 n=10+10)

name                      old speed      new speed       delta
Fields/ASCII/16           38.4MB/s ± 4%  134.9MB/s ± 3%   +251.55%  (p=0.000 n=10+10)
Fields/ASCII/256          43.0MB/s ± 3%  290.6MB/s ± 1%   +575.97%  (p=0.000 n=10+8)
Fields/ASCII/4096         44.4MB/s ± 1%  320.0MB/s ± 2%   +620.90%  (p=0.000 n=10+10)
Fields/ASCII/65536        44.0MB/s ± 1%  260.7MB/s ± 1%   +493.15%  (p=0.000 n=10+10)
Fields/ASCII/1048576      42.0MB/s ± 1%  161.6MB/s ± 2%   +285.21%  (p=0.000 n=10+10)
Fields/Mixed/16           39.4MB/s ± 1%   71.7MB/s ± 1%    +82.20%  (p=0.000 n=10+10)
Fields/Mixed/256          44.3MB/s ± 1%  112.8MB/s ± 1%   +154.64%  (p=0.000 n=9+10)
Fields/Mixed/4096         41.9MB/s ± 1%  101.2MB/s ± 3%   +141.92%  (p=0.000 n=10+10)
Fields/Mixed/65536        41.5MB/s ± 1%   95.5MB/s ± 1%   +130.29%  (p=0.000 n=10+10)
Fields/Mixed/1048576      39.4MB/s ± 1%   82.9MB/s ± 2%   +110.28%  (p=0.000 n=9+10)
FieldsFunc/ASCII/16       40.5MB/s ± 1%   84.9MB/s ± 2%   +109.80%  (p=0.000 n=10+10)
FieldsFunc/ASCII/256      43.4MB/s ± 1%  127.9MB/s ± 1%   +194.58%  (p=0.000 n=10+10)
FieldsFunc/ASCII/4096     44.3MB/s ± 1%  124.2MB/s ± 1%   +180.44%  (p=0.000 n=10+9)
FieldsFunc/ASCII/65536    44.2MB/s ± 1%  120.6MB/s ± 1%   +173.06%  (p=0.000 n=10+9)
FieldsFunc/ASCII/1048576  41.8MB/s ± 1%  100.2MB/s ± 3%   +139.53%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16       39.8MB/s ± 1%   77.8MB/s ± 2%    +95.46%  (p=0.000 n=10+10)
FieldsFunc/Mixed/256      44.9MB/s ± 1%  129.4MB/s ± 1%   +187.97%  (p=0.000 n=10+10)
FieldsFunc/Mixed/4096     42.0MB/s ± 1%  115.6MB/s ± 1%   +175.08%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536    41.6MB/s ± 1%  107.3MB/s ± 1%   +157.75%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576  39.6MB/s ± 1%   91.8MB/s ± 2%   +131.72%  (p=0.000 n=10+10)

name                      old alloc/op   new alloc/op    delta
Fields/ASCII/16              80.0B ± 0%      80.0B ± 0%       ~     (all equal)
Fields/ASCII/256              768B ± 0%       768B ± 0%       ~     (all equal)
Fields/ASCII/4096           9.47kB ± 0%     9.47kB ± 0%       ~     (all equal)
Fields/ASCII/65536           147kB ± 0%      147kB ± 0%       ~     (all equal)
Fields/ASCII/1048576        2.27MB ± 0%     2.27MB ± 0%       ~     (all equal)
Fields/Mixed/16              96.0B ± 0%      96.0B ± 0%       ~     (all equal)
Fields/Mixed/256              768B ± 0%       768B ± 0%       ~     (all equal)
Fields/Mixed/4096           9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
Fields/Mixed/65536           147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
Fields/Mixed/1048576        2.26MB ± 0%     9.61MB ± 0%   +324.89%  (p=0.000 n=10+10)
FieldsFunc/ASCII/16          80.0B ± 0%      80.0B ± 0%       ~     (all equal)
FieldsFunc/ASCII/256          768B ± 0%       768B ± 0%       ~     (all equal)
FieldsFunc/ASCII/4096       9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
FieldsFunc/ASCII/65536       147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
FieldsFunc/ASCII/1048576    2.27MB ± 0%     9.61MB ± 0%   +323.72%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16          96.0B ± 0%      96.0B ± 0%       ~     (all equal)
FieldsFunc/Mixed/256          768B ± 0%       768B ± 0%       ~     (all equal)
FieldsFunc/Mixed/4096       9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536       147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576    2.26MB ± 0%     9.61MB ± 0%   +324.89%  (p=0.000 n=10+10)

name                      old allocs/op  new allocs/op   delta
Fields/ASCII/16               1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/256              1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/4096             1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/65536            1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/1048576          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/16               1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/256              1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/4096             1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
Fields/Mixed/65536            1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
Fields/Mixed/1048576          1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/16           1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/ASCII/256          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/ASCII/4096         1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/65536        1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/1048576      1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16           1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/Mixed/256          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/Mixed/4096         1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536        1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576      1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)

Change-Id: If1926782decc2f60d3b4b8c41c2ce7d8bdedfd8f
Reviewed-on: https://go-review.googlesource.com/55131
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-14 21:08:51 +00:00
Josselin Costanzi
01cd22c687 bytes: add optimized countByte for amd64
Use SSE/AVX2 when counting a single byte.
Inspired from runtime indexbyte implementation.

Benchmark against previous implementation, where
1 byte in every 8 is the one we are looking for:

* On a machine without AVX2
name               old time/op   new time/op     delta
CountSingle/10-4    61.8ns ±10%     15.6ns ±11%    -74.83%  (p=0.000 n=10+10)
CountSingle/32-4     100ns ± 4%       17ns ±10%    -82.54%  (p=0.000 n=10+9)
CountSingle/4K-4    9.66µs ± 3%     0.37µs ± 6%    -96.21%  (p=0.000 n=10+10)
CountSingle/4M-4    11.0ms ± 6%      0.4ms ± 4%    -96.04%  (p=0.000 n=10+10)
CountSingle/64M-4    194ms ± 8%        8ms ± 2%    -95.64%  (p=0.000 n=10+10)

name               old speed     new speed       delta
CountSingle/10-4   162MB/s ±10%    645MB/s ±10%   +297.00%  (p=0.000 n=10+10)
CountSingle/32-4   321MB/s ± 5%   1844MB/s ± 9%   +474.79%  (p=0.000 n=10+9)
CountSingle/4K-4   424MB/s ± 3%  11169MB/s ± 6%  +2533.10%  (p=0.000 n=10+10)
CountSingle/4M-4   381MB/s ± 7%   9609MB/s ± 4%  +2421.88%  (p=0.000 n=10+10)
CountSingle/64M-4  346MB/s ± 7%   7924MB/s ± 2%  +2188.78%  (p=0.000 n=10+10)

* On a machine with AVX2
name               old time/op   new time/op     delta
CountSingle/10-8    37.1ns ± 3%      8.2ns ± 1%    -77.80%  (p=0.000 n=10+10)
CountSingle/32-8    66.1ns ± 3%      9.8ns ± 2%    -85.23%  (p=0.000 n=10+10)
CountSingle/4K-8    7.36µs ± 3%     0.11µs ± 1%    -98.54%  (p=0.000 n=10+10)
CountSingle/4M-8    7.46ms ± 2%     0.15ms ± 2%    -97.95%  (p=0.000 n=10+9)
CountSingle/64M-8    124ms ± 2%        6ms ± 4%    -95.09%  (p=0.000 n=10+10)

name               old speed     new speed       delta
CountSingle/10-8   269MB/s ± 3%   1213MB/s ± 1%   +350.32%  (p=0.000 n=10+10)
CountSingle/32-8   484MB/s ± 4%   3277MB/s ± 2%   +576.66%  (p=0.000 n=10+10)
CountSingle/4K-8   556MB/s ± 3%  37933MB/s ± 1%  +6718.36%  (p=0.000 n=10+10)
CountSingle/4M-8   562MB/s ± 2%  27444MB/s ± 3%  +4783.43%  (p=0.000 n=10+9)
CountSingle/64M-8  543MB/s ± 2%  11054MB/s ± 3%  +1935.81%  (p=0.000 n=10+10)

Fixes #19411

Change-Id: Ieaf20b1fabccabe767c55c66e242e86f3617f883
Reviewed-on: https://go-review.googlesource.com/38258
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-21 20:25:17 +00:00
Aliaksandr Valialkin
8946502776 bytes, strings: optimize Split*
The relevant benchmark results on linux/amd64:

bytes:

SplitSingleByteSeparator-4   25.7ms ± 5%   9.1ms ± 4%  -64.40%  (p=0.000 n=10+10)
SplitMultiByteSeparator-4    13.8ms ±20%   4.3ms ± 8%  -69.23%  (p=0.000 n=10+10)
SplitNSingleByteSeparator-4  1.88µs ± 9%  0.88µs ± 4%  -53.25%  (p=0.000 n=10+10)
SplitNMultiByteSeparator-4   4.83µs ±10%  1.32µs ± 9%  -72.65%  (p=0.000 n=10+10)

strings:

name                         old time/op  new time/op  delta
SplitSingleByteSeparator-4   21.4ms ± 8%   8.5ms ± 5%  -60.19%  (p=0.000 n=10+10)
SplitMultiByteSeparator-4    13.2ms ± 9%   3.9ms ± 4%  -70.29%  (p=0.000 n=10+10)
SplitNSingleByteSeparator-4  1.54µs ± 5%  0.75µs ± 7%  -51.21%  (p=0.000 n=10+10)
SplitNMultiByteSeparator-4   3.57µs ± 8%  1.01µs ±11%  -71.76%  (p=0.000 n=10+10)

Fixes #18973

Change-Id: Ie4bc010c6cc389001e72eab530497c81e5b26f34
Reviewed-on: https://go-review.googlesource.com/36510
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-08 18:39:43 +00:00
Joe Tsai
9a8c69539c bytes, strings: optimize for ASCII sets
In a large codebase within Google, there are thousands of uses of:
	ContainsAny|IndexAny|LastIndexAny|Trim|TrimLeft|TrimRight

An analysis of their usage shows that over 97% of them only use character
sets consisting of only ASCII symbols.

Uses of ContainsAny|IndexAny|LastIndexAny:
	 6% are 1   character  (e.g., "\n" or " ")
	58% are 2-4 characters (e.g., "<>" or "\r\n\t ")
	24% are 5-9 characters (e.g., "()[]*^$")
	10% are 10+ characters (e.g., "+-=&|><!(){}[]^\"~*?:\\/ ")
We optimize for ASCII sets, which are commonly used to search for
"control" characters in some string. We don't optimize for the
single character scenario since IndexRune or IndexByte could be used.

Uses of Trim|TrimLeft|TrimRight:
	71% are 1   character  (e.g., "\n" or " ")
	14% are 2   characters (e.g., "\r\n")
	10% are 3-4 characters (e.g., " \t\r\n")
	 5% are 10+ characters (e.g., "0123456789abcdefABCDEF")
We optimize for the single character case with a simple closured function
that only checks for that character's value. We optimize for the medium
and larger sets using a 16-byte bit-map representing a set of ASCII characters.

The benchmarks below have the following suffix name "%d:%d" where the first
number is the length of the input and the second number is the length
of the charset.

== bytes package ==
benchmark                            old ns/op     new ns/op     delta
BenchmarkIndexAnyASCII/1:1-4         5.09          5.23          +2.75%
BenchmarkIndexAnyASCII/1:2-4         5.81          5.85          +0.69%
BenchmarkIndexAnyASCII/1:4-4         7.22          7.50          +3.88%
BenchmarkIndexAnyASCII/1:8-4         11.0          11.1          +0.91%
BenchmarkIndexAnyASCII/1:16-4        17.5          17.8          +1.71%
BenchmarkIndexAnyASCII/16:1-4        36.0          34.0          -5.56%
BenchmarkIndexAnyASCII/16:2-4        46.6          36.5          -21.67%
BenchmarkIndexAnyASCII/16:4-4        78.0          40.4          -48.21%
BenchmarkIndexAnyASCII/16:8-4        136           47.4          -65.15%
BenchmarkIndexAnyASCII/16:16-4       254           61.5          -75.79%
BenchmarkIndexAnyASCII/256:1-4       542           388           -28.41%
BenchmarkIndexAnyASCII/256:2-4       705           382           -45.82%
BenchmarkIndexAnyASCII/256:4-4       1089          386           -64.55%
BenchmarkIndexAnyASCII/256:8-4       1994          394           -80.24%
BenchmarkIndexAnyASCII/256:16-4      3843          411           -89.31%
BenchmarkIndexAnyASCII/4096:1-4      8522          5873          -31.08%
BenchmarkIndexAnyASCII/4096:2-4      11253         5861          -47.92%
BenchmarkIndexAnyASCII/4096:4-4      17824         5883          -66.99%
BenchmarkIndexAnyASCII/4096:8-4      32053         5871          -81.68%
BenchmarkIndexAnyASCII/4096:16-4     60512         5888          -90.27%
BenchmarkTrimASCII/1:1-4             79.5          70.8          -10.94%
BenchmarkTrimASCII/1:2-4             79.0          105           +32.91%
BenchmarkTrimASCII/1:4-4             79.6          109           +36.93%
BenchmarkTrimASCII/1:8-4             78.8          118           +49.75%
BenchmarkTrimASCII/1:16-4            80.2          132           +64.59%
BenchmarkTrimASCII/16:1-4            243           116           -52.26%
BenchmarkTrimASCII/16:2-4            243           171           -29.63%
BenchmarkTrimASCII/16:4-4            243           176           -27.57%
BenchmarkTrimASCII/16:8-4            241           184           -23.65%
BenchmarkTrimASCII/16:16-4           238           199           -16.39%
BenchmarkTrimASCII/256:1-4           2580          840           -67.44%
BenchmarkTrimASCII/256:2-4           2603          1175          -54.86%
BenchmarkTrimASCII/256:4-4           2572          1188          -53.81%
BenchmarkTrimASCII/256:8-4           2550          1191          -53.29%
BenchmarkTrimASCII/256:16-4          2585          1208          -53.27%
BenchmarkTrimASCII/4096:1-4          39773         12181         -69.37%
BenchmarkTrimASCII/4096:2-4          39946         17231         -56.86%
BenchmarkTrimASCII/4096:4-4          39641         17179         -56.66%
BenchmarkTrimASCII/4096:8-4          39835         17175         -56.88%
BenchmarkTrimASCII/4096:16-4         40229         17215         -57.21%

== strings package ==
benchmark                            old ns/op     new ns/op     delta
BenchmarkIndexAnyASCII/1:1-4         5.94          4.97          -16.33%
BenchmarkIndexAnyASCII/1:2-4         5.94          5.55          -6.57%
BenchmarkIndexAnyASCII/1:4-4         7.45          7.21          -3.22%
BenchmarkIndexAnyASCII/1:8-4         10.8          10.6          -1.85%
BenchmarkIndexAnyASCII/1:16-4        17.4          17.2          -1.15%
BenchmarkIndexAnyASCII/16:1-4        36.4          32.2          -11.54%
BenchmarkIndexAnyASCII/16:2-4        49.6          34.6          -30.24%
BenchmarkIndexAnyASCII/16:4-4        77.5          37.9          -51.10%
BenchmarkIndexAnyASCII/16:8-4        138           45.5          -67.03%
BenchmarkIndexAnyASCII/16:16-4       241           59.1          -75.48%
BenchmarkIndexAnyASCII/256:1-4       509           378           -25.74%
BenchmarkIndexAnyASCII/256:2-4       720           381           -47.08%
BenchmarkIndexAnyASCII/256:4-4       1142          384           -66.37%
BenchmarkIndexAnyASCII/256:8-4       1999          391           -80.44%
BenchmarkIndexAnyASCII/256:16-4      3735          403           -89.21%
BenchmarkIndexAnyASCII/4096:1-4      7973          5824          -26.95%
BenchmarkIndexAnyASCII/4096:2-4      11432         5809          -49.19%
BenchmarkIndexAnyASCII/4096:4-4      18327         5819          -68.25%
BenchmarkIndexAnyASCII/4096:8-4      33059         5828          -82.37%
BenchmarkIndexAnyASCII/4096:16-4     59703         5817          -90.26%
BenchmarkTrimASCII/1:1-4             71.9          71.8          -0.14%
BenchmarkTrimASCII/1:2-4             73.3          103           +40.52%
BenchmarkTrimASCII/1:4-4             71.8          106           +47.63%
BenchmarkTrimASCII/1:8-4             71.2          113           +58.71%
BenchmarkTrimASCII/1:16-4            71.6          128           +78.77%
BenchmarkTrimASCII/16:1-4            152           116           -23.68%
BenchmarkTrimASCII/16:2-4            160           168           +5.00%
BenchmarkTrimASCII/16:4-4            172           170           -1.16%
BenchmarkTrimASCII/16:8-4            200           177           -11.50%
BenchmarkTrimASCII/16:16-4           254           193           -24.02%
BenchmarkTrimASCII/256:1-4           1438          864           -39.92%
BenchmarkTrimASCII/256:2-4           1551          1195          -22.95%
BenchmarkTrimASCII/256:4-4           1770          1200          -32.20%
BenchmarkTrimASCII/256:8-4           2195          1216          -44.60%
BenchmarkTrimASCII/256:16-4          3054          1224          -59.92%
BenchmarkTrimASCII/4096:1-4          21726         12557         -42.20%
BenchmarkTrimASCII/4096:2-4          23586         17508         -25.77%
BenchmarkTrimASCII/4096:4-4          26898         17510         -34.90%
BenchmarkTrimASCII/4096:8-4          33714         17595         -47.81%
BenchmarkTrimASCII/4096:16-4         47429         17700         -62.68%

The benchmarks added test the worst case. For IndexAny, that is when the
charset matches none of the input. For Trim, it is when the charset matches
all of the input.

Change-Id: I970874d101a96b33528fc99b165379abe58cf6ea
Reviewed-on: https://go-review.googlesource.com/31593
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Martin Möhrmann <martisch@uos.de>
2016-10-28 17:37:04 +00:00
Joe Tsai
4b2665786e bytes, strings: fix regression in IndexRune
In all previous versions of Go, the behavior of IndexRune(s, r)
where r was utf.RuneError was that it would effectively return the
index of any invalid UTF-8 byte sequence (include RuneError).
Optimizations made in http://golang.org/cl/28537 and
http://golang.org/cl/28546 altered this undocumented behavior such
that RuneError would only match on the RuneError rune itself.

Although, the new behavior is arguably reasonable, it did break code
that depended on the previous behavior. Thus, we add special checks
to ensure that we preserve the old behavior.

There is a slight performance hit for correctness:
	benchmark                   old ns/op     new ns/op     delta
	BenchmarkIndexRune/10-4     19.3          21.6          +11.92%
	BenchmarkIndexRune/32-4     33.6          35.2          +4.76%
This only occurs on small strings. The performance hit for larger strings
is neglible and not shown.

Fixes #17611

Change-Id: I1d863a741213d46c40b2e1724c41245df52502a5
Reviewed-on: https://go-review.googlesource.com/32123
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-26 23:02:27 +00:00
Emmanuel Odeke
7b40b0c3a3 strings, bytes: panic if Repeat overflows or if given a negative count
Panic if Repeat is given a negative count or
if the value of (len(*) * count) is detected
to overflow.
We panic because we cannot change the
signature of Repeat to return an error.

Fixes #16237

Change-Id: I9f5ba031a5b8533db0582d7a672ffb715143f3fb
Reviewed-on: https://go-review.googlesource.com/29954
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-01 15:47:35 +00:00
Brad Fitzpatrick
9a7ce41d6c bytes: cut 10 seconds off the race builder's benchmark test
Don't benchmark so many sizes during the race builder's benchmark run.

This package doesn't even use goroutines.

Cuts off 10 seconds.

Updates #17104

Change-Id: Ibb2c7272c18b9014a775949c656a5b930f197cd4
Reviewed-on: https://go-review.googlesource.com/29158
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-09-14 18:22:16 +00:00
Hiroshi Ioka
e10286aeda bytes: make IndexRune faster
re-implement IndexRune by IndexByte and Index which are well optimized
to get performance gain.

name                  old time/op   new time/op     delta
IndexRune/10-4         53.2ns ± 1%     29.1ns ± 1%    -45.32%  (p=0.008 n=5+5)
IndexRune/32-4          191ns ± 1%       27ns ± 1%    -85.75%  (p=0.008 n=5+5)
IndexRune/4K-4         23.5µs ± 1%      1.0µs ± 1%    -95.77%  (p=0.008 n=5+5)
IndexRune/4M-4         23.8ms ± 0%      1.0ms ± 2%    -95.90%  (p=0.008 n=5+5)
IndexRune/64M-4         384ms ± 1%       15ms ± 1%    -95.98%  (p=0.008 n=5+5)
IndexRuneASCII/10-4    61.5ns ± 0%     10.3ns ± 4%    -83.17%  (p=0.008 n=5+5)
IndexRuneASCII/32-4     203ns ± 0%       11ns ± 5%    -94.68%  (p=0.008 n=5+5)
IndexRuneASCII/4K-4    23.4µs ± 0%      0.3µs ± 2%    -98.60%  (p=0.008 n=5+5)
IndexRuneASCII/4M-4    24.0ms ± 1%      0.3ms ± 1%    -98.60%  (p=0.008 n=5+5)
IndexRuneASCII/64M-4    386ms ± 2%        6ms ± 1%    -98.57%  (p=0.008 n=5+5)

name                  old speed     new speed       delta
IndexRune/10-4        188MB/s ± 1%    344MB/s ± 1%    +82.91%  (p=0.008 n=5+5)
IndexRune/32-4        167MB/s ± 0%   1175MB/s ± 1%   +603.52%  (p=0.008 n=5+5)
IndexRune/4K-4        174MB/s ± 1%   4117MB/s ± 1%  +2262.71%  (p=0.008 n=5+5)
IndexRune/4M-4        176MB/s ± 0%   4299MB/s ± 2%  +2340.46%  (p=0.008 n=5+5)
IndexRune/64M-4       175MB/s ± 1%   4354MB/s ± 1%  +2388.57%  (p=0.008 n=5+5)
IndexRuneASCII/10-4   163MB/s ± 0%    968MB/s ± 4%   +494.66%  (p=0.008 n=5+5)
IndexRuneASCII/32-4   157MB/s ± 0%   2974MB/s ± 4%  +1788.59%  (p=0.008 n=5+5)
IndexRuneASCII/4K-4   175MB/s ± 0%  12481MB/s ± 2%  +7027.71%  (p=0.008 n=5+5)
IndexRuneASCII/4M-4   175MB/s ± 1%  12510MB/s ± 1%  +7061.15%  (p=0.008 n=5+5)
IndexRuneASCII/64M-4  174MB/s ± 2%  12143MB/s ± 1%  +6881.70%  (p=0.008 n=5+5)

Change-Id: I0632eadb83937c2a9daa7f0ce79df1dee64f992e
Reviewed-on: https://go-review.googlesource.com/28537
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-06 23:32:57 +00:00
Marcel van Lohuizen
9e112a3fe4 bytes: use Run method for benchmarks
Change-Id: I34ab1003099570f0ba511340e697a648de31d08a
Reviewed-on: https://go-review.googlesource.com/23427
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-06-03 07:03:03 +00:00
Emmanuel Odeke
59af53d681 bytes: add ContainsRune
Make package bytes consistent with strings
by adding missing function ContainsRune.

Fixes #15189

Change-Id: Ie09080b389e55bbe070c57aa3bd134053a805423
Reviewed-on: https://go-review.googlesource.com/21710
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2016-04-08 20:24:57 +00:00
Rob Pike
d636d7907c bytes: add ContainsAny
This function is present in the strings package but missing from bytes,
and we would like to keep the two packages consistent.

Add it to bytes, and copy the test over as well.

Fixes #15140

Change-Id: I5dbd28da83a9fe741885794ed15f2af2f826cb3c
Reviewed-on: https://go-review.googlesource.com/21562
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-06 21:17:08 +00:00
Dominik Honnef
b2cf571040 all: delete dead test code
This deletes unused code and helpers from tests.

Change-Id: Ie31d46115f558ceb8da6efbf90c3c204e03b0d7e
Reviewed-on: https://go-review.googlesource.com/20927
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-21 07:10:08 +00:00
Brad Fitzpatrick
5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
Keith Randall
687abca1ea runtime: avoid using REP prefix for IndexByte
REP-prefixed instructions have a large startup cost.
Avoid them like the plague.

benchmark                  old ns/op     new ns/op     delta
BenchmarkIndexByte10-8     22.4          5.34          -76.16%

Fixes #13983

Change-Id: I857e956e240fc9681d053f2584ccf24c1b272bb3
Reviewed-on: https://go-review.googlesource.com/18703
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-26 01:09:53 +00:00
Uttam C Pawar
32add8d7c8 bytes: improve Compare function on amd64 for large byte arrays
This patch contains only loop unrolling change for size > 63B

Following are the performance numbers for various sizes on
On Haswell based system: Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz.

benchcmp go.head.8.25.15.txt go.head.8.25.15.opt.txt
benchmark                       old ns/op     new ns/op     delta
BenchmarkBytesCompare1-4        5.37          5.37          +0.00%
BenchmarkBytesCompare2-4        5.37          5.38          +0.19%
BenchmarkBytesCompare4-4        5.37          5.37          +0.00%
BenchmarkBytesCompare8-4        4.42          4.38          -0.90%
BenchmarkBytesCompare16-4       4.27          4.45          +4.22%
BenchmarkBytesCompare32-4       5.30          5.36          +1.13%
BenchmarkBytesCompare64-4       6.93          6.78          -2.16%
BenchmarkBytesCompare128-4      10.3          9.50          -7.77%
BenchmarkBytesCompare256-4      17.1          13.8          -19.30%
BenchmarkBytesCompare512-4      31.3          22.1          -29.39%
BenchmarkBytesCompare1024-4     62.5          39.0          -37.60%
BenchmarkBytesCompare2048-4     112           73.2          -34.64%

Change-Id: I4eeb1c22732fd62cbac97ba757b0d29f648d4ef1
Reviewed-on: https://go-review.googlesource.com/11871
Reviewed-by: Keith Randall <khr@golang.org>
2015-08-26 03:52:20 +00:00
Dmitry Vyukov
0fb5475bdf bytes, strings: add LastIndexByte
Currently the packages have the following index functions:

func Index(s, sep []byte) int
func IndexAny(s []byte, chars string) int
func IndexByte(s []byte, c byte) int
func IndexFunc(s []byte, f func(r rune) bool) int
func IndexRune(s []byte, r rune) int

func LastIndex(s, sep []byte) int
func LastIndexAny(s []byte, chars string) int
func LastIndexFunc(s []byte, f func(r rune) bool) int

Searching for the last occurrence of a byte is quite common
for string parsing algorithms (e.g. find the last paren on a line).
Also addition of LastIndexByte makes the set more orthogonal.

Change-Id: Ida168849acacf8e78dd70c1354bef9eac5effafe
Reviewed-on: https://go-review.googlesource.com/9500
Reviewed-by: Rob Pike <r@golang.org>
2015-04-30 07:13:18 +00:00
Russ Cox
c007ce824d build: move package sources from src/pkg to src
Preparation was in CL 134570043.
This CL contains only the effect of 'hg mv src/pkg/* src'.
For more about the move, see golang.org/s/go14nopkg.
2014-09-08 00:08:51 -04:00