diff options
author | Denis Vlasenko <vda.linux@googlemail.com> | 2006-12-30 22:52:28 +0300 |
---|---|---|
committer | Denis Vlasenko <vda.linux@googlemail.com> | 2006-12-30 22:52:28 +0300 |
commit | 80602a98bcc3100279e09e1291d47a0adb6addb1 (patch) | |
tree | 7eaed9db7ac11303e1a97ae4e2d2daf2d3860f75 /scripts/basic | |
parent | 1b3e8179a299f3f947e21b9e44e824da89ad1d5a (diff) |
saw commit of vapier@busybox.net (thanks!),
decided to stop doing FOUR memcmp's per each input character.
I should have fixed this much earlier...
Diffstat (limited to 'scripts/basic')
-rw-r--r-- | scripts/basic/fixdep.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c index 2fa78ee6a..65bae4dac 100644 --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -225,31 +225,36 @@ void use_config(char *m, int slen) void parse_config_file(char *map, size_t len) { /* modified for bbox */ - char *end = map + len; + char *end_4 = map + len - 4; /* 4 == length of "USE_" */ + char *end_7 = map + len - 7; char *p = map; char *q; int off; - for (; p < end; p++) { - if (p<end-7 && !memcmp(p, "CONFIG_", 7)) goto conf7; - if (p<end-7 && !memcmp(p, "ENABLE_", 7)) goto conf7; - if (p<end-4 && !memcmp(p, "USE_", 4)) goto conf4; - if (p<end-5 && !memcmp(p, "SKIP_", 5)) goto conf5; + for (; p < end_4; p++) { + if (p < end_7 && p[6] == '_') { + if (!memcmp(p, "CONFIG", 6)) goto conf7; + if (!memcmp(p, "ENABLE", 6)) goto conf7; + } + /* We have at least 5 chars: for() has + * "p < end-4", not "p <= end-4" + * therefore we don't need to check p <= end-5 here */ + if (p[4] == '_') { + if (!memcmp(p, "SKIP", 4)) goto conf5; + } + /* Ehhh, gcc is too stupid to just compare it as 32bit int */ + if (!memcmp(p, "USE_", 4)) goto conf4; continue; - conf4: off = 4; goto conf; - conf5: off = 5; goto conf; + + conf4: off = 4; + conf5: off = 5; conf7: off = 7; - conf: - if (p > map + len - off) - continue; - for (q = p + off; q < map + len; q++) { + p += off; + for (q = p; q < end_4+4; q++) { if (!(isalnum(*q) || *q == '_')) - goto found; + break; } - continue; - - found: - use_config(p+off, q-p-off); + use_config(p, q-p); } } |