diff options
Diffstat (limited to 'innobase/include/sync0sync.ic')
| -rw-r--r-- | innobase/include/sync0sync.ic | 37 |
1 files changed, 13 insertions, 24 deletions
diff --git a/innobase/include/sync0sync.ic b/innobase/include/sync0sync.ic index a32a82d6e8b..e5c6f56d8ba 100644 --- a/innobase/include/sync0sync.ic +++ b/innobase/include/sync0sync.ic @@ -6,6 +6,16 @@ Mutex, the basic synchronization primitive Created 9/5/1995 Heikki Tuuri *******************************************************/ +#if defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86) +/* %z0: Use the size of operand %0 which in our case is *m to determine +instruction size, it should end up as xchgl. "1" in the input constraint, +says that "in" has to go in the same place as "out".*/ +#define TAS(m, in, out) \ + asm volatile ("xchg%z0 %2, %0" \ + : "=g" (*(m)), "=r" (out) \ + : "1" (in)) /* Note: "1" here refers to "=r" (out) */ +#endif + /********************************************************************** Sets the waiters field in a mutex. */ @@ -85,20 +95,10 @@ mutex_test_and_set( return(res); #elif defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86) - ulint* lw; ulint res; - lw = &(mutex->lock_word); - - /* In assembly we use the so-called AT & T syntax where - the order of operands is inverted compared to the ordinary Intel - syntax. The 'l' after the mnemonics denotes a 32-bit operation. - The line after the code tells which values come out of the asm - code, and the second line tells the input to the asm code. */ + TAS(&mutex->lock_word, 1, res); - asm volatile("movl $1, %%eax; xchgl (%%ecx), %%eax" : - "=eax" (res), "=m" (*lw) : - "ecx" (lw)); return(res); #else ibool ret; @@ -137,20 +137,9 @@ mutex_reset_lock_word( __asm MOV ECX, lw __asm XCHG EDX, DWORD PTR [ECX] #elif defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86) - ulint* lw; - - lw = &(mutex->lock_word); - - /* In assembly we use the so-called AT & T syntax where - the order of operands is inverted compared to the ordinary Intel - syntax. The 'l' after the mnemonics denotes a 32-bit operation. */ + ulint res; - asm volatile("movl $0, %%eax; xchgl (%%ecx), %%eax" : - "=m" (*lw) : - "ecx" (lw) : - "eax"); /* gcc does not seem to understand - that our asm code resets eax: tell it - explicitly that after the third ':' */ + TAS(&mutex->lock_word, 0, res); #else mutex->lock_word = 0; |