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Diffstat (limited to 'db2/mutex/sparc.gcc')
| -rw-r--r-- | db2/mutex/sparc.gcc | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/db2/mutex/sparc.gcc b/db2/mutex/sparc.gcc new file mode 100644 index 0000000000..8445a0629b --- /dev/null +++ b/db2/mutex/sparc.gcc @@ -0,0 +1,33 @@ +/* + * @(#)sparc.gcc 10.1 (Sleepycat) 4/12/97 + * + * The ldstub instruction takes the location specified by its first argument + * (a register containing a memory address) and loads its contents into its + * second argument (a register) and atomically sets the contents the location + * specified by its first argument to a byte of 1s. (The value in the second + * argument is never read, but only overwritten.) + * + * The membar instructions are needed to ensure that writes to the lock are + * correctly ordered with writes that occur later in the instruction stream. + * + * For gcc/sparc, 0 is clear, 1 is set. + */ + +#if defined(__sparcv9__) +Does the following code need membar instructions for V9 processors? +#endif + +#define TSL_SET(tsl) ({ \ + register tsl_t *__l = (tsl); \ + register tsl_t __r; \ + __asm__ volatile \ + ("ldstub [%1],%0" \ + : "=r"( __r) : "r" (__l)); \ + !__r; \ +}) + +#define TSL_UNSET(tsl) ({ \ + register tsl_t *__l = (tsl); \ + __asm__ volatile ("stb %%g0,[%0]" : : "r" (__l)); \ +}) +#define TSL_INIT(tsl) TSL_UNSET(tsl) |