x86: make 'constant_test_bit()' take an unsigned bit number

torvalds · torvalds · commit c4295fbb6048 · 2009-01-09T12:49:50.000-08:00
Ingo noticed that using signed arithmetic seems to confuse the gcc
inliner, and make it potentially decide that it's all too complicated.

(Yeah, yeah, it's a constant. It's always positive. Still..)

Based-on: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
@@ -300,7 +300,7 @@ static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
 	return oldbit;
 }
 
-static inline int constant_test_bit(int nr, const volatile unsigned long *addr)
+static inline int constant_test_bit(unsigned int nr, const volatile unsigned long *addr)
 {
 	return ((1UL << (nr % BITS_PER_LONG)) &
 		(((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0;

Original file line number	Diff line number	Diff line change
`@@ -300,7 +300,7 @@ static inline int test_and_change_bit(int nr, volatile unsigned long *addr)`
`300`	`300`	`return oldbit;`
`301`	`301`	`}`
`302`	`302`
`303`		`-static inline int constant_test_bit(int nr, const volatile unsigned long *addr)`
	`303`	`+static inline int constant_test_bit(unsigned int nr, const volatile unsigned long *addr)`
`304`	`304`	`{`
`305`	`305`	`return ((1UL << (nr % BITS_PER_LONG)) &`
`306`	`306`	`(((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0;`