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| author | Alexey Dobriyan <adobriyan@gmail.com> | 2016-10-11 22:51:32 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-12 00:06:30 +0200 |
| commit | 8cfd56d4790423499d03f09f8584e0c6de494ec7 (patch) | |
| tree | 214e9634190641a501cab0393580394a3b4f7eb9 /lib/kstrtox.c | |
| parent | include/linux/ctype.h: make isdigit() table lookupless (diff) | |
| download | linux-8cfd56d4790423499d03f09f8584e0c6de494ec7.tar.xz linux-8cfd56d4790423499d03f09f8584e0c6de494ec7.zip | |
lib/kstrtox.c: smaller _parse_integer()
Set "overflow" bit upon encountering it instead of postponing to the end
of the conversion. Somehow gcc unwedges itself and generates better code:
$ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux
_parse_integer 177 139 -38
Inspired by patch from Zhaoxiu Zeng.
Link: http://lkml.kernel.org/r/20160826221920.GA1909@p183.telecom.by
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/kstrtox.c')
| -rw-r--r-- | lib/kstrtox.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/lib/kstrtox.c b/lib/kstrtox.c index d8a5cf66c316..b8e2080c1a47 100644 --- a/lib/kstrtox.c +++ b/lib/kstrtox.c @@ -48,11 +48,9 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long { unsigned long long res; unsigned int rv; - int overflow; res = 0; rv = 0; - overflow = 0; while (*s) { unsigned int val; @@ -71,15 +69,13 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long */ if (unlikely(res & (~0ull << 60))) { if (res > div_u64(ULLONG_MAX - val, base)) - overflow = 1; + rv |= KSTRTOX_OVERFLOW; } res = res * base + val; rv++; s++; } *p = res; - if (overflow) - rv |= KSTRTOX_OVERFLOW; return rv; } |