Hi Andrew,
This patch exploits some optimization opportunities
similar to those in first two patches I sent a while ago.
In particular:
In arch/x86/boot/printf.c gets rid of unused tail of digits:
const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz";
(we are using 0-9a-f only)
Uses smaller/faster lowercasing (by ORing with 0x20)
if we know that we work on numbers/digits. Makes
strtoul smaller, and also we are getting rid of
static const char small_digits[] = "0123456789abcdefx";
static const char large_digits[] = "0123456789ABCDEFX";
since this works equally well:
static const char digits[16] = "0123456789ABCDEF";
Size savings:
$ size vmlinux.org vmlinux
text data bss dec hex filename
877320 112252 90112 1079684 107984 vmlinux.org
877048 112252 90112 1079412 107874 vmlinux
It may be also a tiny bit faster because code has less
branches now, but I doubt it is measurable.
Patch is run-tested.
Signed-off-by: Denys Vlasenko <[email protected]>
--
vda