Commit f10db627 authored Feb 06, 2008 by Herbert Xu Committed by Linus Torvalds Feb 06, 2008

Avoid divide in IS_ALIGN



I was happy to discover the brand new IS_ALIGN macro and quickly used it in
my code.  To my dismay I found that the generated code used division to
perform the test.

This patch fixes it by changing the % test to an &.  This avoids the
division.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b0940003

include/linux/kernel.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -35,7 +35,7 @@ extern const char linux_proc_banner[];
		#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
		#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
		#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
		#define IS_ALIGNED(x,a) (((x) % ((typeof(x))(a))) == 0)
		#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)

		#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))

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