From 3cbfe485e44d055b9e6a27e47069729375059f8c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 24 Feb 2012 03:36:49 -0500 Subject: Remove useless "retry memory" logic within regex engine. Apparently some primordial version of Spencer's engine needed cdissect() and child functions to be able to continue matching from a previous position when re-called. That is dead code, though, since trivial inspection shows that cdissect can never be entered without having previously done zapmem which resets the relevant retry counter. I have also verified experimentally that no case in the Tcl regression tests reaches cdissect with a nonzero retry value. Accordingly, remove that logic. This doesn't really save any noticeable number of cycles in itself, but it is one step towards making dissect() and cdissect() equivalent, which will allow removing hundreds of lines of near-duplicated code. Since struct subre's "retry" field is no longer particularly related to any kind of retry, rename it to "id". As of this commit it's only used for identifying a subre node in debug printouts, so you might think we should get rid of the field entirely; but I have a plan for another use. --- src/include/regex/regguts.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/include/regex/regguts.h') diff --git a/src/include/regex/regguts.h b/src/include/regex/regguts.h index d420ea8316e..bc5419d98e7 100644 --- a/src/include/regex/regguts.h +++ b/src/include/regex/regguts.h @@ -409,7 +409,7 @@ struct subre #define PREF(f) ((f)&LOCAL) #define PREF2(f1, f2) ((PREF(f1) != 0) ? PREF(f1) : PREF(f2)) #define COMBINE(f1, f2) (UP((f1)|(f2)) | PREF2(f1, f2)) - short retry; /* index into retry memory */ + short id; /* ID of subre (1..ntree) */ int subno; /* subexpression number (for 'b' and '(') */ short min; /* min repetitions for iteration or backref */ short max; /* max repetitions for iteration or backref */ -- cgit v1.2.3