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Add a "contains" fast-path to like_utf8_scalar
#1582
Merged
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This PR uses
memchr
to add a fast path tolike_utf8_scalar
for when the pattern can be processed as a "contains" query. For example, if the pattern is%ABBA%
, then we can check to see if each string containsABBA
instead of building a regular expression.To measure the performance improvement from this fast path, I added a benchmark. Here are the results on my machine:
Since
memchr
does the state-of-the-art SIMD tricks (as far as I know), this technique should even be faster for "contains" queries than the glob-matching suggestion in #1295 .