r12473@Kushana: nickm | 2007-03-06 15:49:45 -0500

Excise PREDICT and PREDICT_FALSE in favor of PREDICT_LIKELY and PREDICT_UNLIKELY.


svn:r9781
This commit is contained in:
Nick Mathewson 2007-03-09 21:39:19 +00:00
parent d26a587309
commit d62e37b4a9
2 changed files with 10 additions and 9 deletions

View File

@ -98,15 +98,17 @@ extern INLINE double U64_TO_DBL(uint64_t x) {
#define ATTR_PURE __attribute__((pure))
#define ATTR_MALLOC __attribute__((malloc))
#define ATTR_NONNULL(x) __attribute__((nonnull x))
#define PREDICT(exp, val) __builtin_expect((exp), (val))
#define PREDICT_LIKELY(exp) PREDICT((exp), 1)
#define PREDICT_UNLIKELY(exp) PREDICT((exp), 0)
/** Macro: Evaluates to <b>exp</b> and hints the compiler that the value
* of <b>exp</b> will probably be true. */
#define PREDICT_LIKELY(exp) __builtin_expect((exp), 1)
/** Macro: Evaluates to <b>exp</b> and hints the compiler that the value
* of <b>exp</b> will probably be false. */
#define PREDICT_UNLIKELY(exp) __builtin_expect((exp), 0)
#else
#define ATTR_NORETURN
#define ATTR_PURE
#define ATTR_MALLOC
#define ATTR_NONNULL(x)
#define PREDICT(exp, val) (exp)
#define PREDICT_LIKELY(exp) (exp)
#define PREDICT_UNLIKELY(exp) (exp)
#endif

View File

@ -39,17 +39,16 @@
#error "Sorry; we don't support building with NDEBUG."
#else
#ifdef __GNUC__
/** Macro: evaluate the expression x, which we expect to be false.
* Used to hint the compiler that a branch won't be taken. */
#define PREDICT_FALSE(x) PREDICT_UNLIKELY((x) == ((typeof(x)) 0))
/* Give an int-valued version of !x that won't confuse PREDICT_UNLIKELY. */
#define IS_FALSE_AS_INT(x) ((x) == ((typeof(x)) 0))
#else
#define PREDICT_FALSE(x) !(x)
#define IS_FALSE_AS_INT(x) !(x)
#endif
/** Like assert(3), but send assertion failures to the log as well as to
* stderr. */
#define tor_assert(expr) do { \
if (PREDICT_FALSE(expr)) { \
if (PREDICT_UNLIKELY(IS_FALSE_AS_INT(expr))) { \
log(LOG_ERR, LD_BUG, "%s:%d: %s: Assertion %s failed; aborting.", \
_SHORT_FILE_, __LINE__, __func__, #expr); \
fprintf(stderr,"%s:%d %s: Assertion %s failed; aborting.\n", \