Using this `reg_cache` is racy across ractors, so don't use it when in a
ractor. Also, its use across ractors can cause a regular expression created
in 1 ractor to be used in another ractor (an isolation bug).
In commit d42b9ffb20, an optimization was introduced that can speed up
Regexp#match by 15% when it matches with strings of different encodings.
This optimization, however, does not work across ractors. To fix this,
we only use the optimization if no ractors have been started. In the
future, we could use atomics for the reference counting if we find it's
needed and if it's more performant.
The backtrace of the misbehaving native thread:
```
* frame #0: 0x0000000189c94388 libsystem_kernel.dylib`__pthread_kill + 8
frame #1: 0x0000000189ccd88c libsystem_pthread.dylib`pthread_kill + 296
frame #2: 0x0000000189bd6c60 libsystem_c.dylib`abort + 124
frame #3: 0x0000000189adb174 libsystem_malloc.dylib`malloc_vreport + 892
frame #4: 0x0000000189adec90 libsystem_malloc.dylib`malloc_report + 64
frame #5: 0x0000000189ae321c libsystem_malloc.dylib`___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32
frame #6: 0x00000001001c3be4 ruby`onig_free_body(reg=0x000000012d84b660) at regcomp.c:5663:5
frame #7: 0x00000001001ba828 ruby`rb_reg_prepare_re(re=4748462304, str=4748451168) at re.c:1680:13
frame #8: 0x00000001001bac58 ruby`rb_reg_onig_match(re=4748462304, str=4748451168, match=(ruby`reg_onig_search [inlined] rbimpl_RB_TYPE_P_fastpath at value_type.h:349:14
ruby`reg_onig_search [inlined] rbimpl_rstring_getmem at rstring.h:391:5
ruby`reg_onig_search at re.c:1781:5), args=0x000000013824b168, regs=0x000000013824b150) at re.c:1708:20
frame #9: 0x00000001001baefc ruby`rb_reg_search_set_match(re=4748462304, str=4748451168, pos=<unavailable>, reverse=0, set_backref_str=1, set_match=0x0000000000000000) at re.c:1809:27
frame #10: 0x00000001001bae80 ruby`rb_reg_search0(re=<unavailable>, str=<unavailable>, pos=<unavailable>, reverse=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at re.c:1861:12 [artificial]
frame #11: 0x0000000100230b90 ruby`rb_pat_search0(pat=<unavailable>, str=<unavailable>, pos=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at string.c:6619:16 [artificial]
frame #12: 0x00000001002287f4 ruby`rb_str_sub_bang [inlined] rb_pat_search(pat=4748462304, str=4748451168, pos=0, set_backref_str=1) at string.c:6626:12
frame #13: 0x00000001002287dc ruby`rb_str_sub_bang(argc=1, argv=0x00000001381280d0, str=4748451168) at string.c:6668:11
frame #14: 0x000000010022826c ruby`rb_str_sub
```
You can reproduce this by running:
```
RUBY_TESTOPTS="--name=/test_str_capitalize/" make test-all TESTS=test/ruby/test_m17n.comb
```
However, you need to run it with multiple ractors at once.
Co-authored-by: jhawthorn <john@hawthorn.email>
https://github.com/ruby/ruby/pull/12801 changed regexp matches to reuse
the backref, which causes memory to leak if the original registers of the
match is not freed.
For example, the following script leaks memory:
10.times do
1_000_000.times do
"aaaaaaaaaaa".gsub(/a/, "")
end
puts `ps -o rss= -p #{$$}`
end
Before:
774256
1535152
2297360
3059280
3821296
4583552
5160304
5091456
5114256
4980192
After:
12480
11440
11696
11632
11632
11760
11824
11824
11824
11888
In gsub is used with a string replacement or a map that doesn't
have a default proc, we know for sure no code can cause the MatchData
to escape the `gsub` call.
In such case, we still have to allocate a new MatchData because we
don't know what is the lifetime of the backref, but for any subsequent
match we can re-use the MatchData we allocated ourselves, reducing
allocations significantly.
This partially fixes [Misc #20652], except when a block is used,
and partially reduce the performance impact of
abc0304cb2 / [Bug #17507]
```
compare-ruby: ruby 3.5.0dev (2025-02-24T09:44:57Z master 5cf146399f) +PRISM [arm64-darwin24]
built-ruby: ruby 3.5.0dev (2025-02-24T10:58:27Z gsub-elude-match da966636e9) +PRISM [arm64-darwin24]
warming up....
| |compare-ruby|built-ruby|
|:----------------|-----------:|---------:|
|escape | 3.577k| 3.697k|
| | -| 1.03x|
|escape_bin | 5.869k| 6.743k|
| | -| 1.15x|
|escape_utf8 | 3.448k| 3.738k|
| | -| 1.08x|
|escape_utf8_bin | 6.361k| 7.267k|
| | -| 1.14x|
```
Co-Authored-By: Étienne Barrié <etienne.barrie@gmail.com>
The section "Special global variables" has changed:
e021754db0: Special Global Variables
2b4b513ef0: Regexp Global Variables
e50b7bf784: Regexp@Global+Variables
[Bug #20653]
This commit refactors how Onigmo handles timeout. Instead of raising a
timeout error, onig_search will return a ONIGERR_TIMEOUT which the
caller can free memory, and then raise a timeout error.
This fixes a memory leak in String#start_with when the regexp times out.
For example:
regex = Regexp.new("^#{"(a*)" * 10_000}x$", timeout: 0.000001)
str = "a" * 1000000 + "x"
10.times do
100.times do
str.start_with?(regex)
rescue
end
puts `ps -o rss= -p #{$$}`
end
Before:
33216
51936
71152
81728
97152
103248
120384
133392
133520
133616
After:
14912
15376
15824
15824
16128
16128
16144
16144
16160
16160
[Feature #18576]
Since outright renaming `ASCII-8BIT` is deemed to backward incompatible,
the next best thing would be to only change its `#inspect`, particularly
in exception messages.
rb_reg_desc was not safe for GC compaction because it took in the C
string and length but not the backing String object so it get moved
during compaction. This commit changes rb_reg_desc to use the string
from the Regexp object.
The test fails when RGENGC_CHECK_MODE is turned on:
TestRegexp#test_inspect_under_gc_compact_stress [test/ruby/test_regexp.rb:474]:
<"(?-mix:\\/)|"> expected but was
<"/\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00/">.
The test fails when RGENGC_CHECK_MODE is turned on:
TestRegexp#test_match_under_gc_compact_stress:
NoMethodError: undefined method `match' for nil
test_regexp.rb:878:in `block in test_match_under_gc_compact_stress'
The test fails when RGENGC_CHECK_MODE is turned on:
TestRegexp#test_to_s_under_gc_compact_stress = 13.46 s
1) Failure:
TestRegexp#test_to_s_under_gc_compact_stress [test/ruby/test_regexp.rb:81]:
<"(?-mix:abcd\u3042)"> expected but was
<"(?-mix:\u5C78\u3030\u5C78\u3030\u5C78\u3030\u5C78\u3030\u5C78\u3030)">.
* 🐛 Fixes [Bug #20039](https://bugs.ruby-lang.org/issues/20039)
When a Regexp is initialized with another Regexp, we simply copy the
properties from the original. However, the flags on the original were
not being copied correctly. This caused an issue when the original had
multibyte characters and was being compared with an ASCII string.
Without the forced encoding flag (`KCODE_FIXED`) transferred on to the
new Regexp, the comparison would fail. See the included test for an
example.
Co-authored-by: Nobuyoshi Nakada <nobu@ruby-lang.org>
- Rename regexp.rdoc to exclude from "Pages". This file is for to be
included in the "class Regexp" document, but it also appeared as a
separate page duplicately.
- Fix links on case-sensitive filesystems.
- Fix to use rdoc-ref instead of converted HTML page names.
When matching an incompatible encoding, the Regexp needs to recompile.
If `usecnt == 0`, then we can reuse the `ptr` because nothing else is
using it. This avoids allocating another `regex_t`.
This speeds up matches that switch to incompatible encodings by 15%.
Branch:
```
Regex#match? with different encoding
1.431M (± 1.3%) i/s - 7.264M in 5.076153s
Regex#match? with same encoding
16.858M (± 1.1%) i/s - 85.347M in 5.063279s
```
Base:
```
Regex#match? with different encoding
1.248M (± 2.0%) i/s - 6.342M in 5.083151s
Regex#match? with same encoding
16.377M (± 1.1%) i/s - 82.519M in 5.039504s
```
Script:
```
regex = /foo/
str1 = "日本語"
str2 = "English".force_encoding("ASCII-8BIT")
Benchmark.ips do |x|
x.report("Regex#match? with different encoding") do |times|
i = 0
while i < times
regex.match?(str1)
regex.match?(str2)
i += 1
end
end
x.report("Regex#match? with same encoding") do |times|
i = 0
while i < times
regex.match?(str1)
i += 1
end
end
end
```
Existing strscan releases rely on this C API. It means that the current
Ruby master doesn't work if your Gemfile.lock has strscan unless it's
locked to 3.0.7, which is not released yet.
To fix it, let's not remove the C API we've exposed to users.
rb_reg_onig_match performs preparation, error handling, and cleanup for
matching a regex against a string. This reduces repetitive code and
removes the need for StringScanner to access internal data of regex.
