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More backref performance - no strncmp


I think that using strncmp to match backreferences is incorrect because it
fails when matching nuls, not to mention inefficient.  Also, the return
value of memcmp and strncmp is quite `complicated' to compute while we only
need a yes/no answer.  For this reason the attached patch replaces strncmp
with a customized memcmp.  Performance improvement is on the order of 5%
(2.1 s before, 1.98s after on factor.sed).

2002-10-23  Paolo Bonzini  (bonzini@gnu.org)

        * posix/regexec.c (my_memcmp): new function.
        Used instead of strncmp throughout the file.

|_  _  _ __
|_)(_)| ),'
------- '---

Attachment: regex-no-strncmp.patch
Description: Binary data


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