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x86, bitops: remove use of "sbb" to return CF

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Use SETC instead of SBB to return the value of CF from assembly. Using
SETcc enables uniformity with other flags-returning pieces of assembly
code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1465414726-197858-2-git-send-email-hpa@linux.intel.com
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
This commit is contained in:
H. Peter Anvin
2016-06-08 12:38:37 -07:00
committed by H. Peter Anvin
parent f5967101e9
commit 2823d4da5d
5 changed files with 31 additions and 34 deletions
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18
arch/x86/include/asm/sync_bitops.h
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@@ -79,10 +79,10 @@ static inline void sync_change_bit(long nr, volatile unsigned long *addr)
*/
static inline int sync_test_and_set_bit(long nr, volatile unsigned long *addr)
{
int oldbit;
unsigned char oldbit;
asm volatile("lock; bts %2,%1\n\tsbbl %0,%0"
: "=r" (oldbit), "+m" (ADDR)
asm volatile("lock; bts %2,%1\n\tsetc %0"
: "=qm" (oldbit), "+m" (ADDR)
: "Ir" (nr) : "memory");
return oldbit;
}
@@ -97,10 +97,10 @@ static inline int sync_test_and_set_bit(long nr, volatile unsigned long *addr)
*/
static inline int sync_test_and_clear_bit(long nr, volatile unsigned long *addr)
{
int oldbit;
unsigned char oldbit;
asm volatile("lock; btr %2,%1\n\tsbbl %0,%0"
: "=r" (oldbit), "+m" (ADDR)
asm volatile("lock; btr %2,%1\n\tsetc %0"
: "=qm" (oldbit), "+m" (ADDR)
: "Ir" (nr) : "memory");
return oldbit;
}
@@ -115,10 +115,10 @@ static inline int sync_test_and_clear_bit(long nr, volatile unsigned long *addr)
*/
static inline int sync_test_and_change_bit(long nr, volatile unsigned long *addr)
{
int oldbit;
unsigned char oldbit;
asm volatile("lock; btc %2,%1\n\tsbbl %0,%0"
: "=r" (oldbit), "+m" (ADDR)
asm volatile("lock; btc %2,%1\n\tsetc %0"
: "=qm" (oldbit), "+m" (ADDR)
: "Ir" (nr) : "memory");
return oldbit;
}