From b862f3b099f3ea672c7438c0b282ce8201d39dfc Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 8 Jul 2006 15:24:18 -0700 Subject: i386: improve and correct inline asm memory constraints Use "+m" rather than a combination of "=m" and "m" for improved clarity and consistency. This also fixes some inlines that incorrectly didn't tell the compiler that they read the old value at all, potentially causing the compiler to generate bogus code. It appear that all of those potential bugs were hidden by the use of extra "volatile" specifiers on the data structures in question, though. Signed-off-by: Linus Torvalds --- include/asm-i386/rwlock.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/asm-i386/rwlock.h') diff --git a/include/asm-i386/rwlock.h b/include/asm-i386/rwlock.h index 94f00195d543..96b0bef2ea56 100644 --- a/include/asm-i386/rwlock.h +++ b/include/asm-i386/rwlock.h @@ -37,7 +37,7 @@ "popl %%eax\n\t" \ "1:\n", \ "subl $1,%0\n\t", \ - "=m" (*(volatile int *)rw) : : "memory") + "+m" (*(volatile int *)rw) : : "memory") #define __build_read_lock(rw, helper) do { \ if (__builtin_constant_p(rw)) \ @@ -63,7 +63,7 @@ "popl %%eax\n\t" \ "1:\n", \ "subl $" RW_LOCK_BIAS_STR ",%0\n\t", \ - "=m" (*(volatile int *)rw) : : "memory") + "+m" (*(volatile int *)rw) : : "memory") #define __build_write_lock(rw, helper) do { \ if (__builtin_constant_p(rw)) \ -- cgit v1.2.3