linux/arch
David S. Miller 4efcac3a24 sparc: Optimize strncpy_from_user() zero byte search.
Compute a mask that will only have 0x80 in the bytes which
had a zero in them.  The formula is:

	~(((x & 0x7f7f7f7f) + 0x7f7f7f7f) | x | 0x7f7f7f7f)

In the inner word iteration, we have to compute the "x | 0x7f7f7f7f"
part, so we can reuse that in the above calculation.

Once we have this mask, we perform divide and conquer to find the
highest 0x80 location.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-23 19:20:20 -07:00
..
alpha Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
arm Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 20:33:19 -07:00
avr32 init_task: Replace CONFIG_HAVE_GENERIC_INIT_TASK 2012-05-05 13:00:46 +02:00
blackfin Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
c6x Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
cris cris: Use common threadinfo allocator 2012-05-08 14:08:44 +02:00
frv Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
h8300 init_task: Replace CONFIG_HAVE_GENERIC_INIT_TASK 2012-05-05 13:00:46 +02:00
hexagon Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 20:33:19 -07:00
ia64 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
m32r m32r: Use common threadinfo allocator 2012-05-08 14:08:45 +02:00
m68k Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
microblaze Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
mips Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
mn10300 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
openrisc Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
parisc Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
powerpc Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
s390 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
score score: Use common threadinfo allocator 2012-05-08 14:08:46 +02:00
sh Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
sparc sparc: Optimize strncpy_from_user() zero byte search. 2012-05-23 19:20:20 -07:00
tile Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
um Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
unicore32 init_task: Replace CONFIG_HAVE_GENERIC_INIT_TASK 2012-05-05 13:00:46 +02:00
x86 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
xtensa Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-21 19:43:57 -07:00
.gitignore
Kconfig Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00