f_has(): fast-path for features not in has_list[]#19550
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mattn wants to merge 1 commit intovim:masterfrom
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f_has(): fast-path for features not in has_list[]#19550mattn wants to merge 1 commit intovim:masterfrom
mattn wants to merge 1 commit intovim:masterfrom
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Move runtime-checked features (patch-*, vim_starting, ttyin, etc.)
before the has_list[] linear scan so that common queries like
has('patch-9.1.xxxx') skip the ~198-entry table lookup entirely.
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zeertzjq
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…ure scan
Problem: The has() function is slow because it performs a linear scan
of the feature list for every call.
Solution: Move common runtime checks and the patch-version parser to the
beginning of the f_has() function (Yasuhiro Matsumoto).
closes: vim/vim#19550
vim/vim@327e0e3
Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>
zeertzjq
added a commit
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Mar 3, 2026
…ure scan
Problem: The has() function is slow because it performs a linear scan
of the feature list for every call.
Solution: Move common runtime checks and the patch-version parser to the
beginning of the f_has() function (Yasuhiro Matsumoto).
closes: vim/vim#19550
vim/vim@327e0e3
Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>
zeertzjq
added a commit
to zeertzjq/neovim
that referenced
this pull request
Mar 3, 2026
…ure scan
Problem: The has() function is slow because it performs a linear scan
of the feature list for every call.
Solution: Move common runtime checks and the patch-version parser to the
beginning of the f_has() function (Yasuhiro Matsumoto).
closes: vim/vim#19550
vim/vim@327e0e3
Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>
zeertzjq
added a commit
to neovim/neovim
that referenced
this pull request
Mar 3, 2026
…ure scan (#38135) Problem: The has() function is slow because it performs a linear scan of the feature list for every call. Solution: Move common runtime checks and the patch-version parser to the beginning of the f_has() function (Yasuhiro Matsumoto). closes: vim/vim#19550 vim/vim@327e0e3 Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>
ZieMcd
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Mar 6, 2026
…ure scan (neovim#38135) Problem: The has() function is slow because it performs a linear scan of the feature list for every call. Solution: Move common runtime checks and the patch-version parser to the beginning of the f_has() function (Yasuhiro Matsumoto). closes: vim/vim#19550 vim/vim@327e0e3 Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>
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When querying
has()for things likepatch-*,vim_starting,gui_running, etc., these were only checked after a linear scan through all ~198 entries inhas_list[]. Since none of them exist in that table, the scan always came up empty before reaching the actual check.This moves those runtime-checked features before the
has_list[]scan so we skip the unnecessary work.Called
has()1000000 times per item, averaged over 3 runs:Items that hit the fast-path are 20-28% faster. No regression for items looked up via
has_list[].