Commit Graph

69 Commits

Author SHA1 Message Date
Oleg Bulatov 7263540146 regexp: Regexp shouldn't keep references to inputs
If you try to find something in a slice of bytes using a Regexp object,
the byte array will not be released by GC until you use the Regexp object
on another slice of bytes. It happens because the Regexp object keep
references to the input data in its cache.

Change-Id: I873107f15c1900aa53ccae5d29dbc885b9562808
Reviewed-on: https://go-review.googlesource.com/96715
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-23 16:58:48 +00:00
Daniel Martí d4b2168b23 regexp/syntax: make Op an fmt.Stringer
Using stringer.

Fixes #22684.

Change-Id: I62fbde5dcb337cf269686615616bd39a27491ac1
Reviewed-on: https://go-review.googlesource.com/95355
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-02-20 15:33:50 +00:00
Ahmet Soormally bb355ed5eb regexp: dont use builtin type as variable name
The existing implementation declares a variable error which collides
with builting type error.

This change simply renames error variable to err.

Change-Id: Ib56c2530f37f53ec70fdebb825a432d4c550cd04
Reviewed-on: https://go-review.googlesource.com/87775
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
2018-02-19 23:40:33 +00:00
Josh Bleecher Snyder df5997b99b regexp: don't allocate when All methods find no matches
name                old time/op    new time/op    delta
FindAllNoMatches-8     216ns ± 3%     122ns ± 2%   -43.52%  (p=0.000 n=10+10)

name                old alloc/op   new alloc/op   delta
FindAllNoMatches-8      240B ± 0%        0B       -100.00%  (p=0.000 n=10+10)

name                old allocs/op  new allocs/op  delta
FindAllNoMatches-8      1.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)

This work was supported by Sourcegraph.

Change-Id: I30aac201370ccfb40a6ff637402020ac20f61f70
Reviewed-on: https://go-review.googlesource.com/87418
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-13 18:44:40 +00:00
Joe Tsai b53088a634 Revert "go/printer: forbid empty line before first comment in block"
This reverts commit 08f19bbde1.

Reason for revert:
The changed transformation takes effect on a larger set
of code snippets than expected.

For example, this:
    func foo() {

        // Comment
        bar()

    }
becomes:
    func foo() {
        // Comment
        bar()

    }

This is an unintended consequence.

Change-Id: Ifca88d6267dab8a8170791f7205124712bf8ace8
Reviewed-on: https://go-review.googlesource.com/81335
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Joe Tsai <joetsai@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-12-01 01:12:26 +00:00
Joe Tsai 08f19bbde1 go/printer: forbid empty line before first comment in block
To improve readability when exported fields are removed,
forbid the printer from emitting an empty line before the first comment
in a const, var, or type block.
Also, when printing the "Has filtered or unexported fields." message,
add an empty line before it to separate the message from the struct
or interfact contents.

Before the change:
<<<
type NamedArg struct {

        // Name is the name of the parameter placeholder.
        //
        // If empty, the ordinal position in the argument list will be
        // used.
        //
        // Name must omit any symbol prefix.
        Name string

        // Value is the value of the parameter.
        // It may be assigned the same value types as the query
        // arguments.
        Value interface{}
        // contains filtered or unexported fields
}
>>>

After the change:
<<<
type NamedArg struct {
        // Name is the name of the parameter placeholder.
        //
        // If empty, the ordinal position in the argument list will be
        // used.
        //
        // Name must omit any symbol prefix.
        Name string

        // Value is the value of the parameter.
        // It may be assigned the same value types as the query
        // arguments.
        Value interface{}

        // contains filtered or unexported fields
}
>>>

Fixes #18264

Change-Id: I9fe17ca39cf92fcdfea55064bd2eaa784ce48c88
Reviewed-on: https://go-review.googlesource.com/71990
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-11-02 18:17:22 +00:00
Daniel Martí 7cb3e4fb1d all: unindent some if bodies by exiting early
All of these had a return or break in the else body, so flipping the
condition means we can unindent and simplify.

Change-Id: If93e97504480d18a0dac3f2c8ffe57ab8bcb929c
Reviewed-on: https://go-review.googlesource.com/74190
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-31 20:07:46 +00:00
Marvin Stenger 90d71fe99e all: revert "all: prefer strings.IndexByte over strings.Index"
This reverts https://golang.org/cl/65930.

Fixes #22148

Change-Id: Ie0712621ed89c43bef94417fc32de9af77607760
Reviewed-on: https://go-review.googlesource.com/68430
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-05 23:19:10 +00:00
Ilya Tocar 1ae67965e4 regexp: make (*bitState).push inlinable
By refactoring job.arg from int with 0/1 as the only valid values into bool
and simplifying (*bitState).push, we reduce the number of nodes below the inlining threshold.
This improves backtracking regexp performance by 5-10% and go1 geomean  by 1.7%
Full performance data below:

name                                      old time/op    new time/op     delta
Find-6                                       510ns ± 0%      480ns ± 1%   -5.90%  (p=0.000 n=10+10)
FindString-6                                 504ns ± 1%      479ns ± 1%   -5.10%  (p=0.000 n=10+10)
FindSubmatch-6                               689ns ± 1%      659ns ± 1%   -4.27%  (p=0.000 n=9+10)
FindStringSubmatch-6                         659ns ± 0%      628ns ± 1%   -4.69%  (p=0.000 n=8+10)
Literal-6                                    174ns ± 1%      171ns ± 1%   -1.50%  (p=0.000 n=10+10)
NotLiteral-6                                2.89µs ± 1%     2.72µs ± 0%   -5.84%  (p=0.000 n=10+9)
MatchClass-6                                4.65µs ± 1%     4.28µs ± 1%   -7.96%  (p=0.000 n=10+10)
MatchClass_InRange-6                        4.15µs ± 1%     3.80µs ± 0%   -8.61%  (p=0.000 n=10+8)
ReplaceAll-6                                2.72µs ± 1%     2.60µs ± 1%   -4.68%  (p=0.000 n=10+10)
AnchoredLiteralShortNonMatch-6               158ns ± 1%      153ns ± 1%   -3.03%  (p=0.000 n=10+10)
AnchoredLiteralLongNonMatch-6                176ns ± 1%      176ns ± 0%     ~     (p=1.000 n=10+9)
AnchoredShortMatch-6                         260ns ± 0%      255ns ± 1%   -1.84%  (p=0.000 n=9+10)
AnchoredLongMatch-6                          456ns ± 0%      455ns ± 0%   -0.19%  (p=0.008 n=8+10)
OnePassShortA-6                             1.13µs ± 1%     1.12µs ± 0%   -0.57%  (p=0.046 n=10+8)
NotOnePassShortA-6                          1.14µs ± 1%     1.14µs ± 1%     ~     (p=0.162 n=10+10)
OnePassShortB-6                              908ns ± 0%      893ns ± 0%   -1.60%  (p=0.000 n=8+9)
NotOnePassShortB-6                           857ns ± 0%      803ns ± 1%   -6.34%  (p=0.000 n=8+10)
OnePassLongPrefix-6                          190ns ± 0%      190ns ± 1%     ~     (p=0.059 n=8+10)
OnePassLongNotPrefix-6                       722ns ± 1%      722ns ± 1%     ~     (p=0.451 n=10+10)
MatchParallelShared-6                        810ns ± 2%      807ns ± 2%     ~     (p=0.643 n=10+10)
MatchParallelCopied-6                       72.1ns ± 1%     69.4ns ± 1%   -3.81%  (p=0.000 n=10+10)
QuoteMetaAll-6                               213ns ± 2%      216ns ± 3%     ~     (p=0.284 n=10+10)
QuoteMetaNone-6                             89.7ns ± 1%     89.8ns ± 1%     ~     (p=0.616 n=10+10)
Match/Easy0/32-6                             127ns ± 1%      127ns ± 1%     ~     (p=0.977 n=10+10)
Match/Easy0/1K-6                             566ns ± 0%      566ns ± 0%     ~     (p=1.000 n=8+8)
Match/Easy0/32K-6                           9.30µs ± 1%     9.28µs ± 1%     ~     (p=0.529 n=10+10)
Match/Easy0/1M-6                             460µs ± 1%      460µs ± 1%     ~     (p=0.853 n=10+10)
Match/Easy0/32M-6                           15.0ms ± 0%     15.1ms ± 0%   +0.77%  (p=0.000 n=9+8)
Match/Easy0i/32-6                           2.10µs ± 1%     1.98µs ± 0%   -6.02%  (p=0.000 n=10+8)
Match/Easy0i/1K-6                           61.5µs ± 0%     57.2µs ± 0%   -6.97%  (p=0.000 n=10+9)
Match/Easy0i/32K-6                          2.75ms ± 0%     2.72ms ± 0%   -1.10%  (p=0.000 n=9+9)
Match/Easy0i/1M-6                           88.0ms ± 0%     86.9ms ± 1%   -1.29%  (p=0.000 n=8+10)
Match/Easy0i/32M-6                           2.82s ± 0%      2.77s ± 1%   -1.81%  (p=0.000 n=8+10)
Match/Easy1/32-6                             123ns ± 1%      124ns ± 1%   +0.90%  (p=0.001 n=10+10)
Match/Easy1/1K-6                            1.70µs ± 1%     1.65µs ± 0%   -3.18%  (p=0.000 n=9+10)
Match/Easy1/32K-6                           69.1µs ± 0%     68.4µs ± 1%   -0.95%  (p=0.000 n=8+10)
Match/Easy1/1M-6                            2.46ms ± 1%     2.42ms ± 1%   -1.66%  (p=0.000 n=10+10)
Match/Easy1/32M-6                           78.4ms ± 1%     77.5ms ± 0%   -1.08%  (p=0.000 n=10+9)
Match/Medium/32-6                           2.07µs ± 1%     1.91µs ± 1%   -7.69%  (p=0.000 n=10+10)
Match/Medium/1K-6                           62.8µs ± 0%     58.0µs ± 1%   -7.70%  (p=0.000 n=8+10)
Match/Medium/32K-6                          2.63ms ± 1%     2.58ms ± 1%   -2.14%  (p=0.000 n=10+10)
Match/Medium/1M-6                           84.6ms ± 0%     82.5ms ± 0%   -2.37%  (p=0.000 n=8+9)
Match/Medium/32M-6                           2.71s ± 0%      2.64s ± 0%   -2.46%  (p=0.000 n=10+9)
Match/Hard/32-6                             3.26µs ± 1%     2.98µs ± 1%   -8.49%  (p=0.000 n=10+10)
Match/Hard/1K-6                              100µs ± 0%       90µs ± 1%   -9.55%  (p=0.000 n=9+10)
Match/Hard/32K-6                            3.82ms ± 0%     3.82ms ± 1%     ~     (p=0.515 n=8+10)
Match/Hard/1M-6                              122ms ± 1%      123ms ± 0%   +0.66%  (p=0.000 n=10+8)
Match/Hard/32M-6                             3.89s ± 1%      3.91s ± 1%     ~     (p=0.105 n=10+10)
Match/Hard1/32-6                            18.1µs ± 1%     16.1µs ± 1%  -11.31%  (p=0.000 n=10+10)
Match/Hard1/1K-6                             565µs ± 0%      493µs ± 1%  -12.65%  (p=0.000 n=8+10)
Match/Hard1/32K-6                           18.8ms ± 0%     18.8ms ± 1%     ~     (p=0.905 n=9+10)
Match/Hard1/1M-6                             602ms ± 1%      602ms ± 1%     ~     (p=0.278 n=9+10)
Match/Hard1/32M-6                            19.1s ± 1%      19.2s ± 1%   +0.31%  (p=0.035 n=9+10)
Match_onepass_regex/32-6                    6.32µs ± 1%     6.34µs ± 1%     ~     (p=0.060 n=10+10)
Match_onepass_regex/1K-6                     204µs ± 1%      204µs ± 1%     ~     (p=0.842 n=9+10)
Match_onepass_regex/32K-6                   6.53ms ± 0%     6.55ms ± 1%   +0.36%  (p=0.005 n=10+10)
Match_onepass_regex/1M-6                     209ms ± 0%      208ms ± 1%   -0.65%  (p=0.034 n=8+10)
Match_onepass_regex/32M-6                    6.72s ± 0%      6.68s ± 1%   -0.74%  (p=0.000 n=9+10)
CompileOnepass/^(?:(?:(?:.(?:$))?))...-6    7.02µs ± 1%     7.02µs ± 1%     ~     (p=0.671 n=10+10)
CompileOnepass/^abcd$-6                     5.65µs ± 1%     5.65µs ± 1%     ~     (p=0.411 n=10+9)
CompileOnepass/^(?:(?:a{0,})*?)$-6          7.06µs ± 1%     7.06µs ± 1%     ~     (p=0.912 n=10+10)
CompileOnepass/^(?:(?:a+)*)$-6              6.40µs ± 1%     6.41µs ± 1%     ~     (p=0.699 n=10+10)
CompileOnepass/^(?:(?:a|(?:aa)))$-6         8.18µs ± 2%     8.16µs ± 1%     ~     (p=0.529 n=10+10)
CompileOnepass/^(?:[^\s\S])$-6              5.08µs ± 1%     5.17µs ± 1%   +1.77%  (p=0.000 n=9+10)
CompileOnepass/^(?:(?:(?:a*)+))$-6          6.86µs ± 1%     6.85µs ± 0%     ~     (p=0.190 n=10+9)
CompileOnepass/^[a-c]+$-6                   5.14µs ± 1%     5.11µs ± 0%   -0.53%  (p=0.041 n=10+10)
CompileOnepass/^[a-c]*$-6                   5.62µs ± 1%     5.63µs ± 1%     ~     (p=0.382 n=10+10)
CompileOnepass/^(?:a*)$-6                   5.76µs ± 1%     5.73µs ± 1%   -0.41%  (p=0.008 n=9+10)
CompileOnepass/^(?:(?:aa)|a)$-6             7.89µs ± 1%     7.84µs ± 1%   -0.66%  (p=0.020 n=10+10)
CompileOnepass/^...$-6                      5.38µs ± 1%     5.38µs ± 1%     ~     (p=0.857 n=9+10)
CompileOnepass/^(?:a|(?:aa))$-6             7.80µs ± 2%     7.82µs ± 1%     ~     (p=0.342 n=10+10)
CompileOnepass/^a((b))c$-6                  7.75µs ± 1%     7.78µs ± 1%     ~     (p=0.172 n=10+10)
CompileOnepass/^a.[l-nA-Cg-j]?e$-6          8.39µs ± 1%     8.42µs ± 1%     ~     (p=0.138 n=10+10)
CompileOnepass/^a((b))$-6                   6.92µs ± 1%     6.95µs ± 1%     ~     (p=0.159 n=10+10)
CompileOnepass/^a(?:(b)|(c))c$-6            10.0µs ± 1%     10.0µs ± 1%     ~     (p=0.896 n=10+10)
CompileOnepass/^a(?:b|c)$-6                 5.62µs ± 1%     5.66µs ± 1%   +0.71%  (p=0.023 n=10+10)
CompileOnepass/^a(?:b?|c)$-6                8.49µs ± 1%     8.43µs ± 1%   -0.69%  (p=0.010 n=10+10)
CompileOnepass/^a(?:b?|c+)$-6               9.26µs ± 1%     9.28µs ± 1%     ~     (p=0.448 n=10+10)
CompileOnepass/^a(?:bc)+$-6                 6.52µs ± 1%     6.46µs ± 2%   -1.02%  (p=0.003 n=10+10)
CompileOnepass/^a(?:[bcd])+$-6              6.29µs ± 1%     6.32µs ± 1%     ~     (p=0.256 n=10+10)
CompileOnepass/^a((?:[bcd])+)$-6            7.77µs ± 1%     7.79µs ± 1%     ~     (p=0.105 n=10+10)
CompileOnepass/^a(:?b|c)*d$-6               14.0µs ± 1%     13.9µs ± 1%   -0.69%  (p=0.003 n=10+10)
CompileOnepass/^.bc(d|e)*$-6                8.96µs ± 1%     9.06µs ± 1%   +1.20%  (p=0.000 n=10+9)
CompileOnepass/^loooooooooooooooooo...-6     219µs ± 1%      220µs ± 1%   +0.63%  (p=0.006 n=9+10)
[Geo mean]                                  31.6µs          31.1µs        -1.82%

name                                      old speed      new speed       delta
QuoteMetaAll-6                            65.5MB/s ± 2%   64.8MB/s ± 3%     ~     (p=0.315 n=10+10)
QuoteMetaNone-6                            290MB/s ± 1%    290MB/s ± 1%     ~     (p=0.755 n=10+10)
Match/Easy0/32-6                           250MB/s ± 0%    251MB/s ± 1%     ~     (p=0.277 n=8+9)
Match/Easy0/1K-6                          1.81GB/s ± 0%   1.81GB/s ± 0%     ~     (p=0.408 n=8+10)
Match/Easy0/32K-6                         3.52GB/s ± 1%   3.53GB/s ± 1%     ~     (p=0.529 n=10+10)
Match/Easy0/1M-6                          2.28GB/s ± 1%   2.28GB/s ± 1%     ~     (p=0.853 n=10+10)
Match/Easy0/32M-6                         2.24GB/s ± 0%   2.23GB/s ± 0%   -0.76%  (p=0.000 n=9+8)
Match/Easy0i/32-6                         15.2MB/s ± 1%   16.2MB/s ± 0%   +6.43%  (p=0.000 n=10+9)
Match/Easy0i/1K-6                         16.6MB/s ± 0%   17.9MB/s ± 0%   +7.48%  (p=0.000 n=10+9)
Match/Easy0i/32K-6                        11.9MB/s ± 0%   12.0MB/s ± 0%   +1.11%  (p=0.000 n=9+9)
Match/Easy0i/1M-6                         11.9MB/s ± 0%   12.1MB/s ± 1%   +1.31%  (p=0.000 n=8+10)
Match/Easy0i/32M-6                        11.9MB/s ± 0%   12.1MB/s ± 1%   +1.84%  (p=0.000 n=8+10)
Match/Easy1/32-6                           260MB/s ± 1%    258MB/s ± 1%   -0.91%  (p=0.001 n=10+10)
Match/Easy1/1K-6                           601MB/s ± 1%    621MB/s ± 0%   +3.28%  (p=0.000 n=9+10)
Match/Easy1/32K-6                          474MB/s ± 0%    479MB/s ± 1%   +0.96%  (p=0.000 n=8+10)
Match/Easy1/1M-6                           426MB/s ± 1%    433MB/s ± 1%   +1.68%  (p=0.000 n=10+10)
Match/Easy1/32M-6                          428MB/s ± 1%    433MB/s ± 0%   +1.09%  (p=0.000 n=10+9)
Match/Medium/32-6                         15.4MB/s ± 1%   16.7MB/s ± 1%   +8.23%  (p=0.000 n=10+9)
Match/Medium/1K-6                         16.3MB/s ± 1%   17.7MB/s ± 1%   +8.43%  (p=0.000 n=9+10)
Match/Medium/32K-6                        12.5MB/s ± 1%   12.7MB/s ± 1%   +2.15%  (p=0.000 n=10+10)
Match/Medium/1M-6                         12.4MB/s ± 0%   12.7MB/s ± 0%   +2.44%  (p=0.000 n=8+9)
Match/Medium/32M-6                        12.4MB/s ± 0%   12.7MB/s ± 0%   +2.52%  (p=0.000 n=10+9)
Match/Hard/32-6                           9.82MB/s ± 1%  10.73MB/s ± 1%   +9.29%  (p=0.000 n=10+10)
Match/Hard/1K-6                           10.2MB/s ± 0%   11.3MB/s ± 1%  +10.56%  (p=0.000 n=9+10)
Match/Hard/32K-6                          8.58MB/s ± 0%   8.58MB/s ± 1%     ~     (p=0.554 n=8+10)
Match/Hard/1M-6                           8.59MB/s ± 1%   8.53MB/s ± 0%   -0.70%  (p=0.000 n=10+8)
Match/Hard/32M-6                          8.62MB/s ± 1%   8.59MB/s ± 1%     ~     (p=0.098 n=10+10)
Match/Hard1/32-6                          1.77MB/s ± 1%   1.99MB/s ± 1%  +12.40%  (p=0.000 n=10+8)
Match/Hard1/1K-6                          1.81MB/s ± 1%   2.08MB/s ± 1%  +14.55%  (p=0.000 n=10+10)
Match/Hard1/32K-6                         1.74MB/s ± 0%   1.74MB/s ± 0%     ~     (p=0.108 n=9+10)
Match/Hard1/1M-6                          1.74MB/s ± 0%   1.74MB/s ± 1%     ~     (p=1.000 n=9+10)
Match/Hard1/32M-6                         1.75MB/s ± 0%   1.75MB/s ± 1%     ~     (p=0.157 n=9+10)
Match_onepass_regex/32-6                  5.05MB/s ± 0%   5.05MB/s ± 1%     ~     (p=0.262 n=8+10)
Match_onepass_regex/1K-6                  5.02MB/s ± 1%   5.02MB/s ± 1%     ~     (p=0.677 n=9+10)
Match_onepass_regex/32K-6                 5.02MB/s ± 0%   4.99MB/s ± 0%   -0.47%  (p=0.000 n=10+9)
Match_onepass_regex/1M-6                  5.01MB/s ± 0%   5.04MB/s ± 1%   +0.68%  (p=0.017 n=8+10)
Match_onepass_regex/32M-6                 4.99MB/s ± 0%   5.03MB/s ± 1%   +0.74%  (p=0.000 n=10+10)
[Geo mean]                                29.1MB/s        29.8MB/s        +2.44%

go1 data for reference

name                     old time/op    new time/op    delta
BinaryTree17-6              4.39s ± 1%     4.37s ± 0%   -0.58%  (p=0.006 n=9+9)
Fannkuch11-6                5.13s ± 0%     5.18s ± 0%   +0.87%  (p=0.000 n=8+8)
FmtFprintfEmpty-6          74.2ns ± 0%    71.7ns ± 3%   -3.41%  (p=0.000 n=10+10)
FmtFprintfString-6          120ns ± 1%     122ns ± 2%     ~     (p=0.333 n=10+10)
FmtFprintfInt-6             127ns ± 1%     127ns ± 1%     ~     (p=0.809 n=10+10)
FmtFprintfIntInt-6          186ns ± 0%     188ns ± 1%   +1.02%  (p=0.002 n=8+10)
FmtFprintfPrefixedInt-6     223ns ± 1%     222ns ± 2%     ~     (p=0.421 n=10+10)
FmtFprintfFloat-6           374ns ± 0%     376ns ± 1%   +0.43%  (p=0.030 n=8+10)
FmtManyArgs-6               795ns ± 0%     788ns ± 1%   -0.79%  (p=0.000 n=8+9)
GobDecode-6                10.9ms ± 1%    10.9ms ± 0%     ~     (p=0.079 n=10+9)
GobEncode-6                8.60ms ± 1%    8.56ms ± 0%   -0.52%  (p=0.004 n=10+10)
Gzip-6                      378ms ± 1%     386ms ± 1%   +2.28%  (p=0.000 n=10+10)
Gunzip-6                   63.7ms ± 0%    62.3ms ± 0%   -2.22%  (p=0.000 n=9+8)
HTTPClientServer-6          120µs ± 3%     114µs ± 3%   -4.99%  (p=0.000 n=10+10)
JSONEncode-6               20.3ms ± 1%    19.9ms ± 0%   -1.90%  (p=0.000 n=9+10)
JSONDecode-6               84.3ms ± 0%    83.7ms ± 0%   -0.76%  (p=0.000 n=8+8)
Mandelbrot200-6            6.91ms ± 0%    6.89ms ± 0%   -0.31%  (p=0.000 n=9+8)
GoParse-6                  5.49ms ± 0%    5.47ms ± 1%     ~     (p=0.101 n=8+10)
RegexpMatchEasy0_32-6       130ns ± 0%     128ns ± 0%   -1.54%  (p=0.002 n=8+10)
RegexpMatchEasy0_1K-6       322ns ± 1%     322ns ± 0%     ~     (p=0.525 n=10+9)
RegexpMatchEasy1_32-6       124ns ± 0%     124ns ± 0%   -0.32%  (p=0.046 n=8+10)
RegexpMatchEasy1_1K-6       570ns ± 0%     548ns ± 1%   -3.76%  (p=0.000 n=10+10)
RegexpMatchMedium_32-6      196ns ± 0%     183ns ± 1%   -6.61%  (p=0.000 n=8+10)
RegexpMatchMedium_1K-6     64.3µs ± 0%    59.0µs ± 1%   -8.31%  (p=0.000 n=8+10)
RegexpMatchHard_32-6       3.08µs ± 0%    2.80µs ± 0%   -8.96%  (p=0.000 n=8+9)
RegexpMatchHard_1K-6       93.0µs ± 0%    84.5µs ± 1%   -9.17%  (p=0.000 n=8+9)
Revcomp-6                   647ms ± 2%     646ms ± 1%     ~     (p=0.720 n=10+9)
Template-6                 92.3ms ± 0%    91.7ms ± 0%   -0.65%  (p=0.000 n=8+8)
TimeParse-6                 490ns ± 0%     488ns ± 0%   -0.43%  (p=0.000 n=10+10)
TimeFormat-6                513ns ± 0%     513ns ± 1%     ~     (p=0.144 n=9+10)
[Geo mean]                 79.1µs         77.7µs        -1.73%

name                     old speed      new speed      delta
GobDecode-6              70.1MB/s ± 1%  70.3MB/s ± 0%     ~     (p=0.078 n=10+9)
GobEncode-6              89.2MB/s ± 1%  89.7MB/s ± 0%   +0.52%  (p=0.004 n=10+10)
Gzip-6                   51.4MB/s ± 1%  50.2MB/s ± 1%   -2.23%  (p=0.000 n=10+10)
Gunzip-6                  304MB/s ± 0%   311MB/s ± 0%   +2.27%  (p=0.000 n=9+8)
JSONEncode-6             95.8MB/s ± 1%  97.7MB/s ± 0%   +1.93%  (p=0.000 n=9+10)
JSONDecode-6             23.0MB/s ± 0%  23.2MB/s ± 0%   +0.76%  (p=0.000 n=8+8)
GoParse-6                10.6MB/s ± 0%  10.6MB/s ± 1%     ~     (p=0.111 n=8+10)
RegexpMatchEasy0_32-6     244MB/s ± 0%   249MB/s ± 0%   +2.06%  (p=0.000 n=9+10)
RegexpMatchEasy0_1K-6    3.18GB/s ± 1%  3.17GB/s ± 0%     ~     (p=0.211 n=10+9)
RegexpMatchEasy1_32-6     257MB/s ± 0%   258MB/s ± 0%   +0.37%  (p=0.000 n=8+8)
RegexpMatchEasy1_1K-6    1.80GB/s ± 0%  1.87GB/s ± 1%   +3.91%  (p=0.000 n=10+10)
RegexpMatchMedium_32-6   5.08MB/s ± 0%  5.43MB/s ± 1%   +7.03%  (p=0.000 n=8+10)
RegexpMatchMedium_1K-6   15.9MB/s ± 0%  17.4MB/s ± 1%   +9.08%  (p=0.000 n=8+10)
RegexpMatchHard_32-6     10.4MB/s ± 0%  11.4MB/s ± 0%   +9.82%  (p=0.000 n=8+9)
RegexpMatchHard_1K-6     11.0MB/s ± 0%  12.1MB/s ± 1%  +10.10%  (p=0.000 n=8+9)
Revcomp-6                 393MB/s ± 2%   394MB/s ± 1%     ~     (p=0.720 n=10+9)
Template-6               21.0MB/s ± 0%  21.2MB/s ± 0%   +0.66%  (p=0.000 n=8+8)
[Geo mean]               74.2MB/s       76.2MB/s        +2.70%

Updates #21851

Change-Id: Ie88455db925f422a828f8528293790726a9c036b
Reviewed-on: https://go-review.googlesource.com/65491
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-25 19:34:26 +00:00
Marvin Stenger f22ba1f247 all: prefer strings.IndexByte over strings.Index
strings.IndexByte was introduced in go1.2 and it can be used
effectively wherever the second argument to strings.Index is
exactly one byte long.

This avoids generating unnecessary string symbols and saves
a few calls to strings.Index.

Change-Id: I1ab5edb7c4ee9058084cfa57cbcc267c2597e793
Reviewed-on: https://go-review.googlesource.com/65930
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-09-25 17:35:41 +00:00
Kunpei Sakai 5a986eca86 all: fix article typos
a -> an

Change-Id: I7362bdc199e83073a712be657f5d9ba16df3077e
Reviewed-on: https://go-review.googlesource.com/63850
Reviewed-by: Rob Pike <r@golang.org>
2017-09-15 02:39:16 +00:00
Sylvain Zimmer 67da597312 regexp: Remove duplicated function wordRune()
Fixes #21742

Change-Id: Ib56b092c490c27a4ba7ebdb6391f1511794710b8
Reviewed-on: https://go-review.googlesource.com/61034
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2017-09-08 23:39:37 +00:00
Matej Baćo 1fe1512f50 regexp: examples for Regexp.Expand and Regexp.ExpandString functions
Current documentation lacks simple examples for functions Regexp.Expand
and Regexp.ExpandString whose usage is unclear from description alone.
This commit adds examples that demonstrate usage in practical way.

Fixes #21649

Change-Id: I7b2c06c8ab747f69a6578f0595bf0f3c742ac479
Reviewed-on: https://go-review.googlesource.com/59470
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-28 15:34:19 +00:00
Josh Roppo 9ca9f31f0b regexp: example for MatchString function
Change-Id: I5ca5a6689f0679154c24820466f5cf0011d0aaa6
Reviewed-on: https://go-review.googlesource.com/48959
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-07-15 21:13:35 +00:00
Ivan Moscoso 6bfd2d19ff regexp: clarify example for 'FindString'
Clarifying that FindString only provides left-most match

Change-Id: Ic6ecec12cca759fd4b3565ef5901a110843ffd56
Reviewed-on: https://go-review.googlesource.com/48609
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-07-15 20:38:58 +00:00
Kevin Burke 89ebdbb5fd regexp: speed up QuoteMeta with a lookup table
This is the same technique used in CL 24466. By adding a little bit of
size to the binary, we can remove a function call and gain a lot of
performance.

A raw array ([128]bool) would be faster, but is also be 128 bytes
instead of 16.

Running tip on a Mac:

name             old time/op    new time/op     delta
QuoteMetaAll-4      192ns ±12%      120ns ±11%   -37.27%  (p=0.000 n=10+10)
QuoteMetaNone-4     186ns ± 6%       64ns ± 6%   -65.52%  (p=0.000 n=10+10)

name             old speed      new speed       delta
QuoteMetaAll-4   73.2MB/s ±11%  116.6MB/s ±10%   +59.21%  (p=0.000 n=10+10)
QuoteMetaNone-4   139MB/s ± 6%    405MB/s ± 6%  +190.74%  (p=0.000 n=10+10)

Change-Id: I68ce9fe2ef1c28e2274157789b35b0dd6ae3efb5
Reviewed-on: https://go-review.googlesource.com/41495
Run-TryBot: Kevin Burke <kev@inburke.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-28 06:43:14 +00:00
Daniel Martí 7d547b6411 regexp: remove redundant break
Breaks are implicit, and since there is no outer loop this one could not
mean a loop break that was missing a label.

Change-Id: Ie91018db1825aa8285c1aa55c9d28fc7ec7148af
Reviewed-on: https://go-review.googlesource.com/39691
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-25 15:00:06 +00:00
Takuto Ikuta a306a851cc regexp: Use []bool instead of map[uint32]bool in makeOnePass
Variable m is accessed like variable onePassRunes.
So, we can use array instead of map for variable m.

Onepass compile performance is improved 10~20%.

name                                      old time/op    new time/op    delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    4.60µs ± 1%    4.10µs ± 1%  -10.98%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                     3.76µs ± 2%    3.33µs ± 1%  -11.43%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          4.47µs ± 1%    4.14µs ± 1%   -7.49%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4              4.07µs ± 1%    3.81µs ± 2%   -6.60%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         5.21µs ± 1%    4.80µs ± 2%   -7.90%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              3.26µs ± 1%    3.06µs ± 1%   -6.15%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          4.33µs ± 0%    4.04µs ± 3%   -6.78%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                   3.33µs ± 1%    3.06µs ± 4%   -8.24%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                   3.69µs ± 1%    3.39µs ± 4%   -8.26%  (p=0.008 n=5+5)
CompileOnepass/^(?:a*)$-4                   3.78µs ± 2%    3.36µs ± 0%  -11.09%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4             5.11µs ± 1%    4.60µs ± 1%   -9.85%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                      3.51µs ± 1%    3.25µs ± 1%   -7.37%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             5.05µs ± 1%    4.59µs ± 1%   -9.13%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                  5.24µs ± 1%    4.66µs ± 1%  -11.16%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          5.94µs ± 7%    5.02µs ± 1%  -15.62%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   5.34µs ± 7%    4.21µs ± 2%  -21.05%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            7.25µs ± 7%    5.86µs ± 1%  -19.17%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 4.13µs ± 9%    3.35µs ± 1%  -18.99%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                6.48µs ± 4%    5.05µs ± 1%  -22.16%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               7.05µs ± 7%    5.48µs ± 1%  -22.21%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 4.71µs ± 4%    3.85µs ± 0%  -18.14%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4              4.10µs ± 2%    3.69µs ± 1%   -9.98%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4            5.20µs ± 1%    4.59µs ± 0%  -11.72%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               9.29µs ± 2%    8.23µs ± 1%  -11.43%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                6.33µs ± 3%    5.51µs ± 5%  -12.95%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     162µs ± 0%     138µs ± 2%  -14.70%  (p=0.008 n=5+5)

name                                      old alloc/op   new alloc/op   delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    3.38kB ± 0%    3.27kB ± 0%   -3.08%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                     2.74kB ± 0%    2.59kB ± 0%   -5.54%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          3.34kB ± 0%    3.23kB ± 0%   -3.12%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4              2.95kB ± 0%    2.85kB ± 0%   -3.52%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         3.74kB ± 0%    3.58kB ± 0%   -4.07%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              2.45kB ± 0%    2.35kB ± 0%   -4.20%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          3.13kB ± 0%    3.02kB ± 0%   -3.32%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                   2.48kB ± 0%    2.38kB ± 0%   -4.19%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                   2.52kB ± 0%    2.42kB ± 0%   -4.13%  (p=0.008 n=5+5)
CompileOnepass/^(?:a*)$-4                   2.63kB ± 0%    2.53kB ± 0%   -3.95%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4             3.62kB ± 0%    3.47kB ± 0%   -4.19%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                      2.87kB ± 0%    2.78kB ± 0%   -3.34%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             3.62kB ± 0%    3.47kB ± 0%   -4.19%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                  4.38kB ± 0%    4.23kB ± 0%   -3.33%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          4.30kB ± 0%    4.15kB ± 0%   -3.35%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   4.05kB ± 0%    3.90kB ± 0%   -3.56%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            5.30kB ± 0%    5.05kB ± 0%   -4.83%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 2.87kB ± 0%    2.77kB ± 0%   -3.62%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                4.35kB ± 0%    4.21kB ± 0%   -3.31%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               4.58kB ± 0%    4.44kB ± 0%   -3.14%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 3.15kB ± 0%    3.00kB ± 0%   -4.82%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4              2.94kB ± 0%    2.84kB ± 0%   -3.53%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4            4.08kB ± 0%    3.94kB ± 0%   -3.53%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               6.10kB ± 0%    5.85kB ± 0%   -4.19%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                4.46kB ± 0%    4.31kB ± 0%   -3.28%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     135kB ± 0%     127kB ± 0%   -5.88%  (p=0.008 n=5+5)

name                                      old allocs/op  new allocs/op  delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4      47.0 ± 0%      46.0 ± 0%   -2.13%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                       41.0 ± 0%      40.0 ± 0%   -2.44%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4            49.0 ± 0%      48.0 ± 0%   -2.04%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4                44.0 ± 0%      43.0 ± 0%   -2.27%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4           54.0 ± 0%      53.0 ± 0%   -1.85%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4                33.0 ± 0%      32.0 ± 0%   -3.03%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4            46.0 ± 0%      45.0 ± 0%   -2.17%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                     36.0 ± 0%      35.0 ± 0%   -2.78%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                     41.0 ± 0%      40.0 ± 0%   -2.44%  (p=0.008 n=5+5)
CompileOnepass/^(?:a*)$-4                     42.0 ± 0%      41.0 ± 0%   -2.38%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4               53.0 ± 0%      52.0 ± 0%   -1.89%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                        39.0 ± 0%      38.0 ± 0%   -2.56%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4               53.0 ± 0%      52.0 ± 0%   -1.89%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                    53.0 ± 0%      52.0 ± 0%   -1.89%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4            56.0 ± 0%      55.0 ± 0%   -1.79%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                     47.0 ± 0%      46.0 ± 0%   -2.13%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4              65.0 ± 0%      64.0 ± 0%   -1.54%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                   40.0 ± 0%      39.0 ± 0%   -2.50%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                  57.0 ± 0%      56.0 ± 0%   -1.75%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4                 63.0 ± 0%      62.0 ± 0%   -1.59%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                   46.0 ± 0%      45.0 ± 0%   -2.17%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4                43.0 ± 0%      42.0 ± 0%   -2.33%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4              49.0 ± 0%      48.0 ± 0%   -2.04%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4                  101 ± 0%       100 ± 0%   -0.99%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                  60.0 ± 0%      59.0 ± 0%   -1.67%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     1.09k ± 0%     1.08k ± 0%   -0.74%  (p=0.008 n=5+5)

Fixes #19984

Change-Id: I2268b28d068926a057c62751528de15b6de61a7b
Reviewed-on: https://go-review.googlesource.com/40890
Reviewed-by: Ralph Corderoy <ralph@inputplus.co.uk>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-16 15:24:48 +00:00
Ian Lance Taylor 94a9bc960c regexp: document that Longest method is not concurrent-safe
Change-Id: I9ec137502353e65325087dfb60ee9bd68ffd286d
Reviewed-on: https://go-review.googlesource.com/38447
Reviewed-by: Russ Cox <rsc@golang.org>
2017-04-07 21:12:11 +00:00
haya14busa fbe6723903 regexp: reduce allocations at makeOnePass
It reduces needless allocations on compiling onepass regex.

Following CL 38750

name                                      old time/op    new time/op    delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    5.75µs ± 1%    5.51µs ± 2%   -4.25%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                     4.76µs ± 0%    4.52µs ± 1%   -5.06%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          5.56µs ± 0%    5.56µs ± 3%     ~     (p=0.524 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4              5.09µs ± 0%    5.15µs ± 5%     ~     (p=0.690 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         6.53µs ± 0%    6.43µs ± 5%     ~     (p=0.151 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              4.05µs ± 1%    4.00µs ± 2%     ~     (p=0.095 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          5.47µs ± 0%    5.36µs ± 1%   -1.91%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                   4.13µs ± 1%    4.05µs ± 0%   -2.07%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                   4.59µs ± 2%    4.93µs ± 7%   +7.30%  (p=0.016 n=5+5)
CompileOnepass/^(?:a*)$-4                   4.67µs ± 1%    4.82µs ± 8%     ~     (p=0.730 n=4+5)
CompileOnepass/^(?:(?:aa)|a)$-4             6.43µs ± 1%    6.18µs ± 1%   -3.91%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                      4.71µs ± 0%    4.31µs ± 1%   -8.51%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             6.37µs ± 0%    6.17µs ± 0%   -3.23%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                  6.85µs ± 1%    6.50µs ± 1%   -5.15%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          6.99µs ± 1%    6.66µs ± 1%   -4.81%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   6.15µs ± 1%    5.87µs ± 0%   -4.57%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            8.62µs ± 1%    8.21µs ± 1%   -4.77%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 5.76µs ±42%    4.42µs ± 1%  -23.35%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                7.17µs ± 6%    6.86µs ± 0%   -4.39%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               8.08µs ± 2%    7.67µs ± 2%   -4.97%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 5.53µs ± 3%    5.35µs ± 1%   -3.34%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4              5.08µs ± 1%    4.98µs ± 0%   -2.02%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4            6.49µs ± 1%    6.29µs ± 1%   -3.03%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               11.8µs ± 1%    11.4µs ± 3%   -3.98%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                8.02µs ± 1%    7.54µs ± 1%   -6.00%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     228µs ±18%     196µs ± 0%  -14.02%  (p=0.016 n=5+4)

name                                      old alloc/op   new alloc/op   delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    3.41kB ± 0%    3.38kB ± 0%   -0.94%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                     2.75kB ± 0%    2.74kB ± 0%   -0.29%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          3.34kB ± 0%    3.34kB ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:a+)*)$-4              2.95kB ± 0%    2.95kB ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         3.75kB ± 0%    3.74kB ± 0%   -0.43%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              2.46kB ± 0%    2.45kB ± 0%   -0.49%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          3.13kB ± 0%    3.13kB ± 0%     ~     (all equal)
CompileOnepass/^[a-c]+$-4                   2.48kB ± 0%    2.48kB ± 0%     ~     (all equal)
CompileOnepass/^[a-c]*$-4                   2.52kB ± 0%    2.52kB ± 0%     ~     (all equal)
CompileOnepass/^(?:a*)$-4                   2.63kB ± 0%    2.63kB ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:aa)|a)$-4             3.64kB ± 0%    3.62kB ± 0%   -0.44%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                      2.91kB ± 0%    2.87kB ± 0%   -1.37%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             3.64kB ± 0%    3.62kB ± 0%   -0.44%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                  4.39kB ± 0%    4.38kB ± 0%   -0.18%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          4.32kB ± 0%    4.30kB ± 0%   -0.56%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   4.06kB ± 0%    4.05kB ± 0%   -0.39%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            5.31kB ± 0%    5.30kB ± 0%   -0.15%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 2.88kB ± 0%    2.87kB ± 0%   -0.28%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                4.36kB ± 0%    4.35kB ± 0%   -0.18%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               4.59kB ± 0%    4.58kB ± 0%   -0.17%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 3.15kB ± 0%    3.15kB ± 0%     ~     (all equal)
CompileOnepass/^a(?:[bcd])+$-4              2.94kB ± 0%    2.94kB ± 0%     ~     (all equal)
CompileOnepass/^a((?:[bcd])+)$-4            4.09kB ± 0%    4.08kB ± 0%   -0.20%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               6.15kB ± 0%    6.10kB ± 0%   -0.78%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                4.47kB ± 0%    4.46kB ± 0%   -0.36%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     135kB ± 0%     135kB ± 0%     ~     (p=0.810 n=5+5)

name                                      old allocs/op  new allocs/op  delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4      49.0 ± 0%      47.0 ± 0%   -4.08%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                       41.0 ± 0%      41.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:a{0,})*?)$-4            49.0 ± 0%      49.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:a+)*)$-4                44.0 ± 0%      44.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:a|(?:aa)))$-4           54.0 ± 0%      54.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:[^\s\S])$-4                33.0 ± 0%      33.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:(?:a*)+))$-4            46.0 ± 0%      46.0 ± 0%     ~     (all equal)
CompileOnepass/^[a-c]+$-4                     36.0 ± 0%      36.0 ± 0%     ~     (all equal)
CompileOnepass/^[a-c]*$-4                     41.0 ± 0%      41.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:a*)$-4                     42.0 ± 0%      42.0 ± 0%     ~     (all equal)
CompileOnepass/^(?:(?:aa)|a)$-4               53.0 ± 0%      53.0 ± 0%     ~     (all equal)
CompileOnepass/^...$-4                        43.0 ± 0%      39.0 ± 0%   -9.30%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4               53.0 ± 0%      53.0 ± 0%     ~     (all equal)
CompileOnepass/^a((b))c$-4                    53.0 ± 0%      53.0 ± 0%     ~     (all equal)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4            58.0 ± 0%      56.0 ± 0%   -3.45%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                     47.0 ± 0%      47.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:(b)|(c))c$-4              65.0 ± 0%      65.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:b|c)$-4                   40.0 ± 0%      40.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:b?|c)$-4                  57.0 ± 0%      57.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:b?|c+)$-4                 63.0 ± 0%      63.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:bc)+$-4                   46.0 ± 0%      46.0 ± 0%     ~     (all equal)
CompileOnepass/^a(?:[bcd])+$-4                43.0 ± 0%      43.0 ± 0%     ~     (all equal)
CompileOnepass/^a((?:[bcd])+)$-4              49.0 ± 0%      49.0 ± 0%     ~     (all equal)
CompileOnepass/^a(:?b|c)*d$-4                  105 ± 0%       101 ± 0%   -3.81%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                  62.0 ± 0%      60.0 ± 0%   -3.23%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     1.09k ± 0%     1.09k ± 0%     ~     (all equal)

Fixes #19735

Change-Id: Ib90e18e1b06166407b26b2a68b88afbb1f486024
Reviewed-on: https://go-review.googlesource.com/38751
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-29 20:35:08 +00:00
haya14busa f5c1926e93 regexp: reduce allocations at onePassCopy
It reduces needless allocations on compiling onepass regex.

name                                      old time/op    new time/op    delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    6.31µs ± 3%    6.11µs ± 3%     ~     (p=0.056 n=5+5)
CompileOnepass/^abcd$-4                     5.69µs ±12%    4.93µs ± 4%  -13.42%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          7.10µs ±12%    5.82µs ± 5%  -17.95%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4              5.99µs ±10%    6.07µs ±11%     ~     (p=1.000 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         7.36µs ± 4%    7.81µs ±19%     ~     (p=0.310 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              4.71µs ± 3%    4.71µs ± 5%     ~     (p=1.000 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          6.06µs ± 2%    6.23µs ± 9%     ~     (p=0.310 n=5+5)
CompileOnepass/^[a-c]+$-4                   4.74µs ± 4%    4.64µs ± 6%     ~     (p=0.421 n=5+5)
CompileOnepass/^[a-c]*$-4                   5.17µs ± 2%    4.68µs ± 0%   -9.57%  (p=0.016 n=5+4)
CompileOnepass/^(?:a*)$-4                   5.34µs ± 3%    5.08µs ±12%     ~     (p=0.151 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4             7.24µs ± 5%    7.33µs ±12%     ~     (p=0.841 n=5+5)
CompileOnepass/^...$-4                      5.28µs ± 3%    4.99µs ± 9%     ~     (p=0.095 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             7.20µs ± 4%    7.24µs ±10%     ~     (p=0.841 n=5+5)
CompileOnepass/^a((b))c$-4                  7.99µs ± 3%    7.76µs ± 8%     ~     (p=0.151 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          8.30µs ± 5%    7.29µs ± 4%  -12.08%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   7.34µs ± 4%    7.24µs ±19%     ~     (p=0.690 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            9.80µs ± 6%    9.49µs ±18%     ~     (p=0.151 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 5.23µs ± 3%    4.80µs ±10%     ~     (p=0.056 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                8.26µs ± 3%    7.30µs ± 3%  -11.62%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               9.18µs ± 2%    8.16µs ± 2%  -11.06%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 6.16µs ± 3%    6.41µs ±13%     ~     (p=0.548 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4              5.75µs ± 5%    5.50µs ±12%     ~     (p=0.151 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4            7.65µs ± 5%    6.93µs ± 9%     ~     (p=0.056 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               13.0µs ± 1%    12.1µs ± 2%   -6.91%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                9.20µs ± 4%    8.25µs ± 3%  -10.38%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     254µs ± 2%     220µs ± 6%  -13.47%  (p=0.008 n=5+5)

name                                      old alloc/op   new alloc/op   delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4    3.92kB ± 0%    3.41kB ± 0%  -13.06%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                     3.20kB ± 0%    2.75kB ± 0%  -14.00%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4          3.85kB ± 0%    3.34kB ± 0%  -13.31%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4              3.46kB ± 0%    2.95kB ± 0%  -14.78%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4         4.20kB ± 0%    3.75kB ± 0%  -10.67%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4              3.10kB ± 0%    2.46kB ± 0%  -20.62%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4          3.64kB ± 0%    3.13kB ± 0%  -14.07%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                   3.06kB ± 0%    2.48kB ± 0%  -18.85%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                   3.10kB ± 0%    2.52kB ± 0%  -18.60%  (p=0.008 n=5+5)
CompileOnepass/^(?:a*)$-4                   3.21kB ± 0%    2.63kB ± 0%  -17.96%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4             4.09kB ± 0%    3.64kB ± 0%  -10.96%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                      3.42kB ± 0%    2.91kB ± 0%  -14.95%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4             4.09kB ± 0%    3.64kB ± 0%  -10.96%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                  5.67kB ± 0%    4.39kB ± 0%  -22.59%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4          5.73kB ± 0%    4.32kB ± 0%  -24.58%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                   5.41kB ± 0%    4.06kB ± 0%  -24.85%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4            6.40kB ± 0%    5.31kB ± 0%  -17.00%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                 3.46kB ± 0%    2.88kB ± 0%  -16.67%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                5.77kB ± 0%    4.36kB ± 0%  -24.41%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4               5.94kB ± 0%    4.59kB ± 0%  -22.64%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                 3.60kB ± 0%    3.15kB ± 0%  -12.44%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4              3.46kB ± 0%    2.94kB ± 0%  -14.81%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4            5.50kB ± 0%    4.09kB ± 0%  -25.62%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4               7.24kB ± 0%    6.15kB ± 0%  -15.03%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                5.75kB ± 0%    4.47kB ± 0%  -22.25%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     225kB ± 0%     135kB ± 0%  -39.99%  (p=0.008 n=5+5)

name                                      old allocs/op  new allocs/op  delta
CompileOnepass/^(?:(?:(?:.(?:$))?))...-4      52.0 ± 0%      49.0 ± 0%   -5.77%  (p=0.008 n=5+5)
CompileOnepass/^abcd$-4                       44.0 ± 0%      41.0 ± 0%   -6.82%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a{0,})*?)$-4            52.0 ± 0%      49.0 ± 0%   -5.77%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a+)*)$-4                47.0 ± 0%      44.0 ± 0%   -6.38%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:a|(?:aa)))$-4           57.0 ± 0%      54.0 ± 0%   -5.26%  (p=0.008 n=5+5)
CompileOnepass/^(?:[^\s\S])$-4                36.0 ± 0%      33.0 ± 0%   -8.33%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:(?:a*)+))$-4            49.0 ± 0%      46.0 ± 0%   -6.12%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]+$-4                     39.0 ± 0%      36.0 ± 0%   -7.69%  (p=0.008 n=5+5)
CompileOnepass/^[a-c]*$-4                     44.0 ± 0%      41.0 ± 0%   -6.82%  (p=0.008 n=5+5)
CompileOnepass/^(?:a*)$-4                     45.0 ± 0%      42.0 ± 0%   -6.67%  (p=0.008 n=5+5)
CompileOnepass/^(?:(?:aa)|a)$-4               56.0 ± 0%      53.0 ± 0%   -5.36%  (p=0.008 n=5+5)
CompileOnepass/^...$-4                        46.0 ± 0%      43.0 ± 0%   -6.52%  (p=0.008 n=5+5)
CompileOnepass/^(?:a|(?:aa))$-4               56.0 ± 0%      53.0 ± 0%   -5.36%  (p=0.008 n=5+5)
CompileOnepass/^a((b))c$-4                    57.0 ± 0%      53.0 ± 0%   -7.02%  (p=0.008 n=5+5)
CompileOnepass/^a.[l-nA-Cg-j]?e$-4            62.0 ± 0%      58.0 ± 0%   -6.45%  (p=0.008 n=5+5)
CompileOnepass/^a((b))$-4                     51.0 ± 0%      47.0 ± 0%   -7.84%  (p=0.008 n=5+5)
CompileOnepass/^a(?:(b)|(c))c$-4              69.0 ± 0%      65.0 ± 0%   -5.80%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b|c)$-4                   43.0 ± 0%      40.0 ± 0%   -6.98%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c)$-4                  61.0 ± 0%      57.0 ± 0%   -6.56%  (p=0.008 n=5+5)
CompileOnepass/^a(?:b?|c+)$-4                 67.0 ± 0%      63.0 ± 0%   -5.97%  (p=0.008 n=5+5)
CompileOnepass/^a(?:bc)+$-4                   49.0 ± 0%      46.0 ± 0%   -6.12%  (p=0.008 n=5+5)
CompileOnepass/^a(?:[bcd])+$-4                46.0 ± 0%      43.0 ± 0%   -6.52%  (p=0.008 n=5+5)
CompileOnepass/^a((?:[bcd])+)$-4              53.0 ± 0%      49.0 ± 0%   -7.55%  (p=0.008 n=5+5)
CompileOnepass/^a(:?b|c)*d$-4                  109 ± 0%       105 ± 0%   -3.67%  (p=0.008 n=5+5)
CompileOnepass/^.bc(d|e)*$-4                  66.0 ± 0%      62.0 ± 0%   -6.06%  (p=0.008 n=5+5)
CompileOnepass/^loooooooooooooooooo...-4     1.10k ± 0%     1.09k ± 0%   -0.91%  (p=0.008 n=5+5)

Fixes #19735

Change-Id: Ic68503aaa08e42fafcf7e11cf1f584d674f5ea7b
Reviewed-on: https://go-review.googlesource.com/38750
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-28 17:58:10 +00:00
Martin Möhrmann e74c6cd3c0 regexp: add ASCII fast path for context methods
The step method implementations check directly if the next rune
only needs one byte to be decoded and avoid calling utf8.DecodeRune
for such ASCII characters.

Introduce the same fast path optimization for rune decoding
for the context methods.

Results for regexp benchmarks that use the context methods:

name                            old time/op  new time/op  delta
AnchoredLiteralShortNonMatch-4  97.5ns ± 1%  94.8ns ± 2%  -2.80%  (p=0.000 n=45+43)
AnchoredShortMatch-4             163ns ± 1%   160ns ± 1%  -1.84%  (p=0.000 n=46+47)
NotOnePassShortA-4               742ns ± 2%   742ns ± 2%    ~     (p=0.440 n=49+50)
NotOnePassShortB-4               535ns ± 1%   533ns ± 2%  -0.37%  (p=0.005 n=46+48)
OnePassLongPrefix-4              169ns ± 2%   166ns ± 2%  -2.06%  (p=0.000 n=50+49)

Change-Id: Ib302d9e8c63333f02695369fcf9963974362e335
Reviewed-on: https://go-review.googlesource.com/38256
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-23 00:08:20 +00:00
haya14busa 8a16d7d40a regexp: reduce allocs in regexp.Match for onepass regex
There were no allocations in regexp.Match for *non* onepass regex
because m.matchcap length is reset to zero (ncap=0 for regexp.Match).

But, as for onepass regex, m.matchcap length remains as it is even when
ncap=0 and it leads needless allocations.

benchmark                                    old ns/op      new ns/op      delta
BenchmarkMatch_onepass_regex/32-4      6465           4628           -28.41%
BenchmarkMatch_onepass_regex/1K-4      208324         151558         -27.25%
BenchmarkMatch_onepass_regex/32K-4     7230259        5834492        -19.30%
BenchmarkMatch_onepass_regex/1M-4      234379810      166310682      -29.04%
BenchmarkMatch_onepass_regex/32M-4     7903529363     4981119950     -36.98%

benchmark                                    old MB/s     new MB/s     speedup
BenchmarkMatch_onepass_regex/32-4      4.95         6.91         1.40x
BenchmarkMatch_onepass_regex/1K-4      4.92         6.76         1.37x
BenchmarkMatch_onepass_regex/32K-4     4.53         5.62         1.24x
BenchmarkMatch_onepass_regex/1M-4      4.47         6.30         1.41x
BenchmarkMatch_onepass_regex/32M-4     4.25         6.74         1.59x

benchmark                                    old allocs     new allocs     delta
BenchmarkMatch_onepass_regex/32-4      32             0              -100.00%
BenchmarkMatch_onepass_regex/1K-4      1024           0              -100.00%
BenchmarkMatch_onepass_regex/32K-4     32768          0              -100.00%
BenchmarkMatch_onepass_regex/1M-4      1048576        0              -100.00%
BenchmarkMatch_onepass_regex/32M-4     104559255      0              -100.00%

benchmark                                    old bytes      new bytes     delta
BenchmarkMatch_onepass_regex/32-4      512            0             -100.00%
BenchmarkMatch_onepass_regex/1K-4      16384          0             -100.00%
BenchmarkMatch_onepass_regex/32K-4     524288         0             -100.00%
BenchmarkMatch_onepass_regex/1M-4      16777216       0             -100.00%
BenchmarkMatch_onepass_regex/32M-4     2019458128     0             -100.00%

Fixes #19573

Change-Id: I033982d0003ebb0360bb40b92eb3941c781ec74d
Reviewed-on: https://go-review.googlesource.com/38270
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-03-23 00:02:55 +00:00
Daniel Martí ad74e450ca regexp/syntax: remove unused flags parameter
Found by github.com/mvdan/unparam.

Change-Id: I186d2afd067e97eb05d65c4599119b347f82867d
Reviewed-on: https://go-review.googlesource.com/37840
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-06 19:11:09 +00:00
Ingo Oeser 9aed16e96d regexp: avoid alloc in QuoteMeta when not quoting
Many users quote literals in regular expressions just in case.
No need to allocate then.

Note: Also added benchmarks for quoting and not quoting.

	name             old time/op    new time/op     delta
	QuoteMetaAll-4      629ns ± 6%      654ns ± 5%    +4.01%        (p=0.001 n=20+19)
	QuoteMetaNone-4    1.02µs ± 6%     0.20µs ± 0%   -80.73%        (p=0.000 n=18+20)

	name             old speed      new speed       delta
	QuoteMetaAll-4   22.3MB/s ± 6%   21.4MB/s ± 5%    -3.94%        (p=0.001 n=20+19)
	QuoteMetaNone-4  25.3MB/s ± 3%  131.5MB/s ± 0%  +419.28%        (p=0.000 n=17+19)

	name             old alloc/op   new alloc/op    delta
	QuoteMetaAll-4      64.0B ± 0%      64.0B ± 0%      ~     (all samples are equal)
	QuoteMetaNone-4     96.0B ± 0%      0.0B ±NaN%  -100.00%        (p=0.000 n=20+20)

	name             old allocs/op  new allocs/op   delta
	QuoteMetaAll-4       2.00 ± 0%       2.00 ± 0%      ~     (all samples are equal)
	QuoteMetaNone-4      2.00 ± 0%      0.00 ±NaN%  -100.00%        (p=0.000 n=20+20)

Change-Id: I38d50f463cde463115d22534f8eb849e54d899af
Reviewed-on: https://go-review.googlesource.com/31395
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-19 07:09:08 +00:00
Brad Fitzpatrick 7d0642d9d6 regexp: remove dead code
Wasn't convenient enough.

Change-Id: I78270dc22cdb2e264641148e50029a9e4de953cd
Reviewed-on: https://go-review.googlesource.com/30251
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-10-04 14:49:35 +00:00
Brad Fitzpatrick f09d0458d3 regexp: don't run slow benchmarks on race builders
Shave 6.5 minutes off the *-race build time.

The *-race builders run:

    go test -short -race -run=^$ -benchtime=.1s -cpu=4 $PKG

... for each package with benchmarks.

The point isn't to measure the speed of the packages, but rather to
see if there are any races. (which is why a benchtime of 0.1 seconds
is used)

But running in race mode makes things slower and our benchmarks aren't
all very fast to begin with.

The regexp benchmarks in race were taking over 6.5 minutes. With this
CL, it's now 8 seconds.

Updates #17104

Change-Id: I054528d09b1568d37aac9f9b515d6ed90a5cf5b0
Reviewed-on: https://go-review.googlesource.com/29156
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-09-14 18:17:06 +00:00
Aliaksandr Valialkin bea39e63ec regexp: reduce mallocs in Regexp.Find* and Regexp.ReplaceAll*.
This improves Regexp.Find* and Regexp.ReplaceAll* speed:

name                  old time/op    new time/op    delta
Find-4                   345ns ± 1%     314ns ± 1%    -8.94%    (p=0.000 n=9+8)
FindString-4             341ns ± 1%     308ns ± 0%    -9.85%   (p=0.000 n=10+9)
FindSubmatch-4           440ns ± 1%     404ns ± 0%    -8.27%   (p=0.000 n=10+8)
FindStringSubmatch-4     426ns ± 0%     387ns ± 0%    -9.07%   (p=0.000 n=10+9)
ReplaceAll-4            1.75µs ± 1%    1.67µs ± 0%    -4.45%   (p=0.000 n=9+10)

name                  old alloc/op   new alloc/op   delta
Find-4                   16.0B ± 0%     0.0B ±NaN%  -100.00%  (p=0.000 n=10+10)
FindString-4             16.0B ± 0%     0.0B ±NaN%  -100.00%  (p=0.000 n=10+10)
FindSubmatch-4           80.0B ± 0%     48.0B ± 0%   -40.00%  (p=0.000 n=10+10)
FindStringSubmatch-4     64.0B ± 0%     32.0B ± 0%   -50.00%  (p=0.000 n=10+10)
ReplaceAll-4              152B ± 0%      104B ± 0%   -31.58%  (p=0.000 n=10+10)

name                  old allocs/op  new allocs/op  delta
Find-4                    1.00 ± 0%     0.00 ±NaN%  -100.00%  (p=0.000 n=10+10)
FindString-4              1.00 ± 0%     0.00 ±NaN%  -100.00%  (p=0.000 n=10+10)
FindSubmatch-4            2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
FindStringSubmatch-4      2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
ReplaceAll-4              8.00 ± 0%      5.00 ± 0%   -37.50%  (p=0.000 n=10+10)

Fixes #15643

Change-Id: I594fe51172373e2adb98d1d25c76ca2cde54ff48
Reviewed-on: https://go-review.googlesource.com/23030
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-06 17:04:31 +00:00
Tamir Duberstein f88a88402c regexp: add some tests that were fixed in #12980
Also includes a minor golint cleanup in the tests.

Change-Id: I8c0fc81479e635e7cca18d5c48c28b654afa59d8
Reviewed-on: https://go-review.googlesource.com/25380
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-16 18:36:43 +00:00
Marcel van Lohuizen a2a4db7375 unicode: upgrade to version 9.0.0
Changes beyond generated tables:
- Now supports aliases to handle deprecated
  property classes.
- Some Mongolian letters are now modifiers.

Other changes:
- strconv: newly generated table to be in sync
- regexp/syntax: updated maxFold

Fixes #16191

Change-Id: I56bdf21ee2f775f2a82d0465b3772faf5c24cb61
Reviewed-on: https://go-review.googlesource.com/24496
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-28 15:08:11 +00:00
Marcel van Lohuizen ad074e205e regexp: use Run for benchmark
Change-Id: I4d19e3221d3789d4c460b421b2d1484253778068
Reviewed-on: https://go-review.googlesource.com/23429
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
2016-06-01 10:28:01 +00:00
Brad Fitzpatrick cdcb8271a4 regexp/syntax: clarify that \Z means Perl's \Z
Fixes #14793

Change-Id: I408056d096cd6a999fa5e349704b5ea8e26d2e4e
Reviewed-on: https://go-review.googlesource.com/23201
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-18 04:43:32 +00:00
Emmanuel Odeke 53fd522c0d all: make copyright headers consistent with one space after period
Follows suit with https://go-review.googlesource.com/#/c/20111.

Generated by running
$ grep -R 'Go Authors.  All' * | cut -d":" -f1 | while read F;do perl -pi -e 's/Go
Authors.  All/Go Authors. All/g' $F;done

The code in cmd/internal/unvendor wasn't changed.

Fixes #15213

Change-Id: I4f235cee0a62ec435f9e8540a1ec08ae03b1a75f
Reviewed-on: https://go-review.googlesource.com/21819
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-02 13:43:18 +00:00
Michael Matloob 70d95a488d regexp: add a harder regexp to the benchmarks
This regexp has many parallel alternations

Change-Id: I8044f460aa7d18f20cb0452e9470557b87facd6d
Reviewed-on: https://go-review.googlesource.com/22471
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-27 16:40:22 +00:00
Egon Elbre e607abbfd6 unicode: improve SimpleFold performance for ascii
This change significantly speeds up case-insensitive regexp matching.

benchmark                      old ns/op      new ns/op      delta
BenchmarkMatchEasy0i_32-8      2690           1473           -45.24%
BenchmarkMatchEasy0i_1K-8      80404          42269          -47.43%
BenchmarkMatchEasy0i_32K-8     3272187        2076118        -36.55%
BenchmarkMatchEasy0i_1M-8      104805990      66503805       -36.55%
BenchmarkMatchEasy0i_32M-8     3360192200     2126121600     -36.73%

benchmark                      old MB/s     new MB/s     speedup
BenchmarkMatchEasy0i_32-8      11.90        21.72        1.83x
BenchmarkMatchEasy0i_1K-8      12.74        24.23        1.90x
BenchmarkMatchEasy0i_32K-8     10.01        15.78        1.58x
BenchmarkMatchEasy0i_1M-8      10.00        15.77        1.58x
BenchmarkMatchEasy0i_32M-8     9.99         15.78        1.58x

Issue #13288

Change-Id: I94af7bb29e75d60b4f6ee760124867ab271b9642
Reviewed-on: https://go-review.googlesource.com/16943
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-26 21:59:50 +00:00
Matthew Dempsky 0da4dbe232 all: remove unnecessary type conversions
cmd and runtime were handled separately, and I'm intentionally skipped
syscall. This is the rest of the standard library.

CL generated mechanically with github.com/mdempsky/unconvert.

Change-Id: I9e0eff886974dedc37adb93f602064b83e469122
Reviewed-on: https://go-review.googlesource.com/22104
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-15 07:31:45 +00:00
Dominik Honnef fdba5a7544 all: delete dead non-test code
This change removes a lot of dead code. Some of the code has never been
used, not even when it was first commited. The rest shouldn't have
survived refactors.

This change doesn't remove unused routines helpful for debugging, nor
does it remove code that's used in commented out blocks of code that are
only unused temporarily. Furthermore, unused constants weren't removed
when they were part of a set of constants from specifications.

One noteworthy omission from this CL are about 1000 lines of unused code
in cmd/fix, 700 lines of which are the typechecker, which hasn't been
used ever since the pre-Go 1 fixes have been removed. I wasn't sure if
this code should stick around for future uses of cmd/fix or be culled as
well.

Change-Id: Ib714bc7e487edc11ad23ba1c3222d1fd02e4a549
Reviewed-on: https://go-review.googlesource.com/20926
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 06:28:13 +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
David Symonds 248c3a3c7b regexp: avoid copying mutex in (*Regexp).Copy.
There's nothing guaranteeing that the *Regexp isn't in active use,
and so copying the sync.Mutex value is invalid.

Updates #14839.

Change-Id: Iddf52bf69df1b563377922399f64a571f76b95dd
Reviewed-on: https://go-review.googlesource.com/20841
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
2016-03-18 03:56:28 +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
Brad Fitzpatrick 519474451a all: make copyright headers consistent with one space after period
This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.

Go policy has been single space after periods in comments for some time.

The copyright header template at:

    https://golang.org/doc/contribute.html#copyright

also uses a single space.

Make them all consistent.

Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-01 23:34:33 +00:00
Martin Möhrmann fdd0179bb1 all: fix typos and spelling
Change-Id: Icd06d99c42b8299fd931c7da821e1f418684d913
Reviewed-on: https://go-review.googlesource.com/19829
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-24 18:42:29 +00:00
Alberto Donizetti cd41db34bc regexp: remove unreachable code
Found running go vet on the package. It barks that
	regexp/backtrack.go:257: unreachable code
	regexp/backtrack.go:302: unreachable code

For #11041

Change-Id: I0f5ba0d6183108fba3d144991b826273db0ffb09
Reviewed-on: https://go-review.googlesource.com/19824
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-23 15:16:50 +00:00
Nathan VanBenschoten b04f3b06ec all: replace strings.Index with strings.Contains where possible
Change-Id: Ia613f1c37bfce800ece0533a5326fca91d99a66a
Reviewed-on: https://go-review.googlesource.com/18120
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
2016-02-19 01:06:05 +00:00
Paul Wankadia 5ccaf0255b regexp/syntax: fix factoring of common prefixes in alternations
In the past, `a.*?c|a.*?b` was factored to `a.*?[bc]`. Thus, given
"abc" as its input string, the automaton would consume "ab" and
then stop (when unanchored) whereas it should consume all of "abc"
as per leftmost semantics.

Fixes #13812.

Change-Id: I67ac0a353d7793b3d0c9c4aaf22d157621dfe784
Reviewed-on: https://go-review.googlesource.com/18357
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-08 16:41:46 +00:00
Russ Cox 0680e9c0c1 regexp/syntax: fix handling of \Q...\E
It's not a group: must handle the inside as a sequence of literal chars,
not a single literal string.

That is, \Qab\E+ is the same as ab+, not (ab)+.

Fixes #11187.

Change-Id: I5406d05ccf7efff3a7f15395bdb0cfb2bd23a8ed
Reviewed-on: https://go-review.googlesource.com/17233
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-01 22:45:12 +00:00
Caleb Spare e36bf614c8 regexp: fix one-pass compilation
The one-pass transformation is structured as a search over the input
machine for conditions that violate the one-pass requisites. At each
iteration, we should fully explore all non-input paths that proceed from
the current instruction; this is implemented via recursive check calls.
But when we reach instructions that demand input (InstRune*), these
should be put onto the search queue.

Instead of searching this way, the routine previously (effectively)
proceeded through the machine one instruction at a time until finding an
Inst{Match,Fail,Rune*}, calling check on each instruction. This caused
bug #11905, where the transformation stopped before rewriting all
InstAlts as InstAltMatches.

Further, the check function unnecessarily recurred on InstRune*
instructions. (I believe this helps to mask the above bug.)

This change also deletes some unused functions and duplicate test cases.

Fixes #11905.

Change-Id: I5b0b26efea3d3bd01c7479a518b5ed1b886701cd
Reviewed-on: https://go-review.googlesource.com/17195
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-25 17:44:17 +00:00
Caleb Spare d1eedfe132 regexp: fix LiteralPrefix for certain onepass progs
The prefix computation for onepass was incorrectly returning
complete=true when it encountered a beginning-of-text empty width match
(^) in the middle of an expression.

Fix by returning complete only when the prefix is followed by $ and then
an accepting state.

Fixes #11175.

Change-Id: Ie9c4cf5f76c1d2c904a6fb2f016cedb265c19fde
Reviewed-on: https://go-review.googlesource.com/16200
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-25 17:28:33 +00:00
Caleb Spare 937172b247 regexp: add Copy method to Regexp
This helps users who wish to use separate Regexps in each goroutine to
avoid lock contention. Previously they had to parse the expression
multiple times to achieve this.

I used variants of the included benchmark to evaluate this change. I
used the arguments -benchtime 20s -cpu 1,2,4,8,16 on a machine with 16
hardware cores.

Comparing a single shared Regexp vs. copied Regexps, we can see that
lock contention causes huge slowdowns at higher levels of parallelism.
The copied version shows the expected linear speedup.

name              old time/op  new time/op  delta
MatchParallel      366ns ± 0%   370ns ± 0%   +1.09%   (p=0.000 n=10+8)
MatchParallel-2    324ns ±28%   184ns ± 1%  -43.37%  (p=0.000 n=10+10)
MatchParallel-4    352ns ± 5%    93ns ± 1%  -73.70%   (p=0.000 n=9+10)
MatchParallel-8    480ns ± 3%    46ns ± 0%  -90.33%    (p=0.000 n=9+8)
MatchParallel-16   510ns ± 8%    24ns ± 6%  -95.36%   (p=0.000 n=10+8)

I also compared a modified version of Regexp that has no mutex and a
single machine (the "RegexpForSingleGoroutine" rsc mentioned in
https://github.com/golang/go/issues/8232#issuecomment-66096128).

In this next test, I compared using N copied Regexps vs. N separate
RegexpForSingleGoroutines. This shows that, even for this relatively
simple regex, avoiding the lock entirely would only buy about 10-12%
further improvement.

name              old time/op  new time/op  delta
MatchParallel      370ns ± 0%   322ns ± 0%  -12.97%    (p=0.000 n=8+8)
MatchParallel-2    184ns ± 1%   162ns ± 1%  -11.60%  (p=0.000 n=10+10)
MatchParallel-4   92.7ns ± 1%  81.1ns ± 2%  -12.43%  (p=0.000 n=10+10)
MatchParallel-8   46.4ns ± 0%  41.8ns ±10%   -9.78%   (p=0.000 n=8+10)
MatchParallel-16  23.7ns ± 6%  20.6ns ± 1%  -13.14%    (p=0.000 n=8+8)

Updates #8232.

Change-Id: I15201a080c363d1b44104eafed46d8df5e311902
Reviewed-on: https://go-review.googlesource.com/16110
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-25 17:26:37 +00:00
Tamir Duberstein 3aa755b8fb regexp/syntax: correctly print `^` BOL and `$` EOL
Fixes #12980.

Change-Id: I936db2f57f7c4dc80bb8ec32715c4c6b7bf0d708
Reviewed-on: https://go-review.googlesource.com/16112
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-25 17:25:22 +00:00