ChangeSet 1.1591, 2005/05/29 17:13:43+01:00, kaf24@xxxxxxxxxxxxxxxxxxxx
Bit-scanning function take offset/size as an int, not a long, and
return an int. This allows some small optimisation in code produced
for x86/64.
Signed-off-by: Keir Fraser <keir@xxxxxxxxxxxxx>
arch/x86/bitops.c | 42 +++++++++++++++++++++---------------------
include/asm-x86/bitops.h | 24 ++++++++++++------------
2 files changed, 33 insertions(+), 33 deletions(-)
diff -Nru a/xen/arch/x86/bitops.c b/xen/arch/x86/bitops.c
--- a/xen/arch/x86/bitops.c 2005-05-29 13:02:16 -04:00
+++ b/xen/arch/x86/bitops.c 2005-05-29 13:02:16 -04:00
@@ -2,8 +2,8 @@
#include <xen/bitops.h>
#include <xen/lib.h>
-unsigned long __find_first_bit(
- const unsigned long *addr, unsigned long size)
+unsigned int __find_first_bit(
+ const unsigned long *addr, unsigned int size)
{
unsigned long d0, d1, res;
@@ -13,29 +13,29 @@
" je 1f\n\t"
" lea -"STR(BITS_PER_LONG/8)"(%2),%2\n\t"
" bsf (%2),%0\n"
- "1: sub %5,%2\n\t"
- " shl $3,%2\n\t"
- " add %2,%0"
+ "1: sub %%ebx,%%edi\n\t"
+ " shl $3,%%edi\n\t"
+ " add %%edi,%%eax"
: "=&a" (res), "=&c" (d0), "=&D" (d1)
: "1" ((size + BITS_PER_LONG - 1) / BITS_PER_LONG),
- "2" (addr), "b" (addr) : "memory" );
+ "2" (addr), "b" ((int)(long)addr) : "memory" );
return res;
}
-unsigned long __find_next_bit(
- const unsigned long *addr, unsigned long size, unsigned long offset)
+unsigned int __find_next_bit(
+ const unsigned long *addr, unsigned int size, unsigned int offset)
{
const unsigned long *p = addr + (offset / BITS_PER_LONG);
- unsigned long set, bit = offset & (BITS_PER_LONG - 1);
+ unsigned int set, bit = offset & (BITS_PER_LONG - 1);
ASSERT(offset < size);
if ( bit != 0 )
{
/* Look for a bit in the first word. */
- __asm__ ( "bsf %1,%0"
- : "=r" (set) : "r" (*p >> bit), "0" (BITS_PER_LONG) );
+ __asm__ ( "bsf %1,%%"__OP"ax"
+ : "=a" (set) : "r" (*p >> bit), "0" (BITS_PER_LONG) );
if ( set < (BITS_PER_LONG - bit) )
return (offset + set);
offset += BITS_PER_LONG - bit;
@@ -50,8 +50,8 @@
return (offset + set);
}
-unsigned long __find_first_zero_bit(
- const unsigned long *addr, unsigned long size)
+unsigned int __find_first_zero_bit(
+ const unsigned long *addr, unsigned int size)
{
unsigned long d0, d1, d2, res;
@@ -62,28 +62,28 @@
" lea -"STR(BITS_PER_LONG/8)"(%2),%2\n\t"
" xor (%2),%3\n\t"
" bsf %3,%0\n"
- "1: sub %6,%2\n\t"
- " shl $3,%2\n\t"
- " add %2,%0"
+ "1: sub %%ebx,%%edi\n\t"
+ " shl $3,%%edi\n\t"
+ " add %%edi,%%edx"
: "=&d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
: "1" ((size + BITS_PER_LONG - 1) / BITS_PER_LONG),
- "2" (addr), "b" (addr), "3" (-1L) : "memory" );
+ "2" (addr), "b" ((int)(long)addr), "3" (-1L) : "memory" );
return res;
}
-unsigned long __find_next_zero_bit(
- const unsigned long *addr, unsigned long size, unsigned long offset)
+unsigned int __find_next_zero_bit(
+ const unsigned long *addr, unsigned int size, unsigned int offset)
{
const unsigned long *p = addr + (offset / BITS_PER_LONG);
- unsigned long set, bit = offset & (BITS_PER_LONG - 1);
+ unsigned int set, bit = offset & (BITS_PER_LONG - 1);
ASSERT(offset < size);
if ( bit != 0 )
{
/* Look for zero in the first word. */
- __asm__ ( "bsf %1,%0" : "=r" (set) : "r" (~(*p >> bit)) );
+ __asm__ ( "bsf %1,%%"__OP"ax" : "=a" (set) : "r" (~(*p >> bit)) );
if ( set < (BITS_PER_LONG - bit) )
return (offset + set);
offset += BITS_PER_LONG - bit;
diff -Nru a/xen/include/asm-x86/bitops.h b/xen/include/asm-x86/bitops.h
--- a/xen/include/asm-x86/bitops.h 2005-05-29 13:02:17 -04:00
+++ b/xen/include/asm-x86/bitops.h 2005-05-29 13:02:17 -04:00
@@ -248,20 +248,20 @@
constant_test_bit((nr),(addr)) : \
variable_test_bit((nr),(addr)))
-extern unsigned long __find_first_bit(
- const unsigned long *addr, unsigned long size);
-extern unsigned long __find_next_bit(
- const unsigned long *addr, unsigned long size, unsigned long offset);
-extern unsigned long __find_first_zero_bit(
- const unsigned long *addr, unsigned long size);
-extern unsigned long __find_next_zero_bit(
- const unsigned long *addr, unsigned long size, unsigned long offset);
+extern unsigned int __find_first_bit(
+ const unsigned long *addr, unsigned int size);
+extern unsigned int __find_next_bit(
+ const unsigned long *addr, unsigned int size, unsigned int offset);
+extern unsigned int __find_first_zero_bit(
+ const unsigned long *addr, unsigned int size);
+extern unsigned int __find_next_zero_bit(
+ const unsigned long *addr, unsigned int size, unsigned int offset);
/* return index of first bit set in val or BITS_PER_LONG when no bit is set */
-static inline unsigned long __scanbit(unsigned long val)
+static inline unsigned int __scanbit(unsigned long val)
{
__asm__ ( "bsf %1,%0" : "=r" (val) : "r" (val), "0" (BITS_PER_LONG) );
- return val;
+ return (unsigned int)val;
}
/**
@@ -320,10 +320,10 @@
* Returns the bit-number of the first set bit. If no bits are set then the
* result is undefined.
*/
-static __inline__ unsigned long find_first_set_bit(unsigned long word)
+static __inline__ unsigned int find_first_set_bit(unsigned long word)
{
__asm__ ( "bsf %1,%0" : "=r" (word) : "r" (word) );
- return word;
+ return (unsigned int)word;
}
/**
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