Date: Mon, 30 Nov 2009 18:48:07 +0000 (UTC) From: Ed Schouten <ed@FreeBSD.org> To: src-committers@freebsd.org, svn-src-user@freebsd.org Subject: svn commit: r199971 - user/ed/newcons/sys/dev/vt Message-ID: <200911301848.nAUIm77V037655@svn.freebsd.org>
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Author: ed Date: Mon Nov 30 18:48:07 2009 New Revision: 199971 URL: http://svn.freebsd.org/changeset/base/199971 Log: Optimize vtfont_bisearch() for the common case (ASCII). More than 90% of the time we'll probably just display ASCII characters. In almost all cases this is stored in entry 0 of the map, so validate the first map by hand. Modified: user/ed/newcons/sys/dev/vt/vt_font.c Modified: user/ed/newcons/sys/dev/vt/vt_font.c ============================================================================== --- user/ed/newcons/sys/dev/vt/vt_font.c Mon Nov 30 18:26:46 2009 (r199970) +++ user/ed/newcons/sys/dev/vt/vt_font.c Mon Nov 30 18:48:07 2009 (r199971) @@ -53,10 +53,20 @@ vtfont_bisearch(const struct vt_font_map min = 0; max = len - 1; - if (len == 0 || src < map[0].vfm_src || - src > map[max].vfm_src + map[max].vfm_len) + /* Empty font map. */ + if (len == 0) + return (0); + /* Character below minimal entry. */ + if (src < map[0].vfm_src) + return (0); + /* Optimization: ASCII characters occur very often. */ + if (src <= map[0].vfm_src + map[0].vfm_len) + return (src - map[0].vfm_src + map[0].vfm_dst); + /* Character above maximum entry. */ + if (src > map[max].vfm_src + map[max].vfm_len) return (0); + /* Binary search. */ while (max >= min) { mid = (min + max) / 2; if (src < map[mid].vfm_src)
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