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Subject[PATCH] kstrtox: 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.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

lib/kstrtox.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

--- 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;
}

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