Commit Graph

88 Commits

Author SHA1 Message Date
Maxime Coste
d9b4076e3c Regex: Go back to instruction based search of next start
The previous method, which was a bit faster in the general use case,
can hit some cases where we get quadratic behaviour and very slow
matching.

By using an instruction, we can guarantee our complexity of O(N*M)
as we will never have more than N threads (N being the instruction
count) and we run the threads once per codepoint in the subject
string.

That slows down the general case slightly, but ensure we dont have
pathological cases.

This new version is much faster than the previous instruction based
search because it does not use a plain `.*` searcher, but a specific,
smarter instruction specialized for finding the next start if we are
in the correct conditions.
2017-11-01 14:05:15 +08:00
Maxime Coste
3f627058b0 Regex: add support for \0, \cX, \xXX and \uXXXX escapes 2017-11-01 14:05:15 +08:00
Maxime Coste
c423b47109 Regex: compute if codepoints outside of the start chars map can start 2017-11-01 14:05:15 +08:00
Maxime Coste
2c6c0be0c1 Regex: abort compilation as soon as we hit the instruction count limit 2017-11-01 14:05:15 +08:00
Maxime Coste
d44e160aa7 Regex: add a unit test for why lookaheads dont count for start chars anymore 2017-11-01 14:05:15 +08:00
Maxime Coste
87eec79d07 Regex: comment the mutables in CompiledRegex::Instruction and fix their init 2017-11-01 14:05:14 +08:00
Maxime Coste
8b2297f5ca Regex: Introduce a Regex memory domain to track usage separately 2017-11-01 14:05:14 +08:00
Maxime Coste
9ec175f2f8 Regex: use binary search to for character class ranges check 2017-11-01 14:05:14 +08:00
Maxime Coste
6e65589a34 Regex: compute start chars from matchers, do not compute it from lookarounds
Computing potential start characters from lookarounds is more complex
than expected, and not worth the complexity.
2017-11-01 14:05:14 +08:00
Maxime Coste
df16fea82d Regex: rename "flags" with the more common "modifiers" 2017-11-01 14:05:14 +08:00
Maxime Coste
52d443f764 Regex: Correctly handle ignore case mode for start chars computation 2017-11-01 14:05:14 +08:00
Maxime Coste
b8495f0953 Regex: Rework parsing, treat lookarounds as assertions, and flags separately 2017-11-01 14:05:14 +08:00
Maxime Coste
b0233262b8 Regex: Limit programs to std::numeric_limits<uint16_t>::max() instructions 2017-11-01 14:05:14 +08:00
Maxime Coste
8c8dcb3a84 Regex: Fix reverse searching behaviour, again 2017-11-01 14:05:14 +08:00
Maxime Coste
9753bcd0ad Regex: limit explicit quantifiers value (too 1000 for now)
Fixes #1628
2017-11-01 14:05:14 +08:00
Maxime Coste
2b97e4e124 Regex: Fix handling of ^ and $ in backward matching mode 2017-11-01 14:05:14 +08:00
Maxime Coste
5bf4be645a Regex: Fix support for ignore case in lookarounds 2017-11-01 14:05:14 +08:00
Maxime Coste
23b3a221eb Regex: support more than two children in alternations
Avoid deep nested alternations, parse them flattened.
2017-11-01 14:05:14 +08:00
Maxime Coste
fb5243f710 Regex: print instruction index in dump_regex 2017-11-01 14:05:14 +08:00
Maxime Coste
74ed102cab Regex: Tweak definition of character class and control escape tables 2017-11-01 14:05:14 +08:00
Maxime Coste
df73b71dfc Regex: fix lookarounds handling when computing starting chars 2017-11-01 14:05:14 +08:00
Maxime Coste
785cd34b4b Regex: Make boost checking disableable at compile time 2017-11-01 14:05:14 +08:00
Maxime Coste
065bbc8f59 Regex: switch to custom impl, use boost for checking 2017-11-01 14:05:14 +08:00
Maxime Coste
9305fa1369 Regex: Fix lookaround use in moon.kak
(?=[A-Z]\w*) is strictly the same as (?=[A-Z]) as \w* will always
at least match an empty string.
2017-11-01 14:05:14 +08:00
Maxime Coste
cca730193c Regex: Support any char and character classes in lookarounds
Lookarounds still need to be fixed size, but accept character classes
as well as plain literals.
2017-11-01 14:05:14 +08:00
Maxime Coste
db06acdfab Regex: Fix computation of potential starts for lookaheads 2017-11-01 14:05:14 +08:00
Maxime Coste
34b1f1ccb6 Regex: detect when all characters can start and avoid allocating 2017-11-01 14:05:14 +08:00
Maxime Coste
bf3b50a543 Regex: Fix wrong size of character_class_escapes array 2017-11-01 14:05:14 +08:00
Maxime Coste
9ec376135b Regex: Introduce RegexExecFlags::PrevAvailable
Rework assertion code as well.
2017-11-01 14:05:14 +08:00
Maxime Coste
30dacdade2 Regex: deallocate Saves memory on ThreadedRegexVM destruction 2017-11-01 14:05:14 +08:00
Maxime Coste
578640c8a4 Regex: Fix handling of control escapes inside character classes 2017-11-01 14:05:14 +08:00
Maxime Coste
f3736a4b48 Regex: tag instructions as scheduled as well instead of searching
And a few more code cleanup in the ThreadedRegexVM
2017-11-01 14:05:14 +08:00
Maxime Coste
4ff655cc09 Regex: store the processed flag directly in CompiledRegex instructions 2017-11-01 14:05:14 +08:00
Maxime Coste
732b8bc2a4 Regex: abandon bytecode and just use a simple list of instructions
Makes the code simpler.
2017-11-01 14:05:14 +08:00
Maxime Coste
11abd544c6 Regex: avoid infinite loops 2017-11-01 14:05:14 +08:00
Maxime Coste
c47cdc06a7 Regex: Add support for backward matching
Regex can be compiled for backward matching instead of forward matching
and the ThreadedRegexVM is able to iterate in reverse on the subject
string to find the last match instead of the first.
2017-11-01 14:05:14 +08:00
Maxime Coste
071b897e00 Regex: Remove static RegexCompiler::compile 2017-11-01 14:05:14 +08:00
Maxime Coste
52ee62172a Regex: remove use of buffer_utils.hh from regex_impl.cc 2017-11-01 14:05:14 +08:00
Maxime Coste
c375268c2d Regex: Use memcpy to write/read offsets from bytecode
reinterpret_cast was undefined behaviour as we do not guarantee
that offsets are going to be stored properly aligned.
2017-11-01 14:05:14 +08:00
Maxime Coste
b53227d62c Regex: slight cleanup of the unit tests 2017-11-01 14:05:14 +08:00
Maxime Coste
337e58d4f9 Regex: Cleanup character class parsing a bit 2017-11-01 14:05:14 +08:00
Maxime Coste
236751cb84 Regex: Make ThreadedRegexVM a proper class, define a proper interface 2017-11-01 14:05:14 +08:00
Maxime Coste
3b69dda04e Regex: Find potential start position using a map of valid start chars
With this optimization we get close to performance parity with boost
regex on the common use cases in Kakoune.
2017-11-01 14:05:14 +08:00
Maxime Coste
741772aef9 Regex: Optimize single char character classes as literals 2017-11-01 14:05:14 +08:00
Maxime Coste
fabeab1ee1 Regex: reorder lookaround ops, group by direction 2017-11-01 14:05:14 +08:00
Maxime Coste
f1b4931824 Regex: Fix handling of non capturing groups (?:...)
We were wrongly keeping the `:` as a literal content of the group
2017-11-01 14:05:14 +08:00
Maxime Coste
dbb175841b Regex: do not write the search prefix inside the program bytecode
Its faster to have specialized code in the VM directly
2017-11-01 14:05:14 +08:00
Maxime Coste
e0fac20f6c Regex: Use a custom allocated buffer for Saves instead of a Vector 2017-11-01 14:05:14 +08:00
Maxime Coste
51ad8b4c85 Regex: fix handling of negative escaped character classes 2017-11-01 14:05:14 +08:00
Maxime Coste
f007794d9c Regex: introduce RegexExecFlags to control various behaviours 2017-11-01 14:05:14 +08:00