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17 May 2024, 11:00:25 UTC
Revision 72d931046030beb2d13dad6d205be0e228618432 authored by Linus Torvalds on 13 September 2014, 18:14:53 UTC, committed by Linus Torvalds on 13 September 2014, 18:14:53 UTC 
Make ARCH_HAS_FAST_MULTIPLIER a real config variable
 
It used to be an ad-hoc hack defined by the x86 version of
<asm/bitops.h> that enabled a couple of library routines to know whether
an integer multiply is faster than repeated shifts and additions.

This just makes it use the real Kconfig system instead, and makes x86
(which was the only architecture that did this) select the option.

NOTE! Even for x86, this really is kind of wrong.  If we cared, we would
probably not enable this for builds optimized for netburst (P4), where
shifts-and-adds are generally faster than multiplies.  This patch does
*not* change that kind of logic, though, it is purely a syntactic change
with no code changes.

This was triggered by the fact that we have other places that really
want to know "do I want to expand multiples by constants by hand or
not", particularly the hash generation code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 186cec3
History
Tip revision: 72d931046030beb2d13dad6d205be0e228618432 authored by Linus Torvalds on 13 September 2014, 18:14:53 UTC
Make ARCH_HAS_FAST_MULTIPLIER a real config variable
Tip revision: 72d9310
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.gitignore -rw-r--r-- 1.1 KB
.mailmap -rw-r--r-- 4.7 KB
COPYING -rw-r--r-- 18.3 KB
CREDITS -rw-r--r-- 93.8 KB
Kbuild -rw-r--r-- 2.5 KB
Kconfig -rw-r--r-- 252 bytes
MAINTAINERS -rw-r--r-- 279.7 KB
Makefile -rw-r--r-- 52.8 KB
README -rw-r--r-- 18.3 KB
REPORTING-BUGS -rw-r--r-- 7.3 KB

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