Environment cache heuristicts.

* mes.c (ENV_HEAD): New define.
  (assq_ref_cache): Use it.
This commit is contained in:
Jan Nieuwenhuizen 2016-10-21 10:43:32 +02:00
parent 28b695510b
commit 2545605a69
1 changed files with 4 additions and 2 deletions

6
mes.c
View File

@ -295,6 +295,9 @@ assq (scm *x, scm *a)
}
#define ENV_CACHE 1
#define CACHE_SIZE 30
#define ENV_HEAD 15
#if !ENV_CACHE
scm *
assq_ref_cache (scm *x, scm *a) //internal
@ -310,7 +313,6 @@ scm*cache_lookup (scm*x){}
#else // ENV_CACHE
#define CACHE_SIZE 20
scm *env_cache_cars[CACHE_SIZE];
scm *env_cache_cdrs[CACHE_SIZE];
int cache_threshold = 0;
@ -380,7 +382,7 @@ assq_ref_cache (scm *x, scm *a)
int i = 0;
while (a != &scm_nil && x != a->car->car) {i++;a = a->cdr;}
if (a == &scm_nil) return &scm_undefined;
if (i>4*CACHE_SIZE) cache_save (a->car);
if (i>ENV_HEAD) cache_save (a->car);
return a->car->cdr;
}
#endif // ENV_CACHE