Add ASCII fast path to gototab to avoid bsearch#264
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yhirose wants to merge 1 commit intoonetrueawk:stagingfrom
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Add ASCII fast path to gototab to avoid bsearch#264yhirose wants to merge 1 commit intoonetrueawk:stagingfrom
yhirose wants to merge 1 commit intoonetrueawk:stagingfrom
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Each state's gototab gains a direct-indexed array for ASCII code points (0..GOTO_DIRECT-1), letting get_gototab and set_gototab return in a single load on the common path. Non-ASCII still goes through the existing sorted (codepoint, state) entries via bsearch, so behavior is unchanged. On the testdir/Compare.tt suite this cuts total time by ~14%; pure regex matches like /.$/ run about 2.3x faster.
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thanks, I'll think about this change. |
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Add a per-state direct-indexed array for ASCII code points to
gototab,so
get_gototabandset_gototabreturn in a single load on the commonpath. Non-ASCII still falls through to the existing sorted (codepoint,
state) entries via
bsearch, so behavior is unchanged. Same dense-tabletechnique gnulib's
dfa.cuses, narrowed to ASCII.Performance on
testdir/Compare.tt(Apple M1, default-O2 -g):/.$/)Same ratio under
-O3 -DNDEBUG -flto -mcpu=apple-m1.Per-state struct grows by
GOTO_DIRECT * sizeof(int) = 512 bytes,about 5% of the existing per-state
entriescalloc.