1 files changed, 145 insertions, 0 deletions
diff --git a/methods.c b/methods.c
new file mode 100644
index 0000000000..d861323444
--- /dev/null
+++ b/methods.c
@@ -0,0 +1,145 @@
+/************************************************
+
+  methods.c -
+
+  $Author: matz $
+  $Date: 1994/06/17 14:23:50 $
+  created at: Fri Oct  1 17:25:07 JST 1993
+
+  Copyright (C) 1994 Yukihiro Matsumoto
+
+************************************************/
+
+#include "ruby.h"
+#include "ident.h"
+#include "env.h"
+#include "node.h"
+
+#define CACHE_SIZE 577
+#if 0
+#define EXPR1(c,m) (((int)(c)*(m))>>0)
+#else
+#define EXPR1(c,m) ((int)(c)^(m))
+#endif
+
+#define TRIAL 3
+
+struct hash_entry {		/* method hash table. */
+    ID mid;			/* method's id */
+    struct RClass *class;	/* receiver's class */
+    struct RClass *origin;	/* where method defined  */
+    struct RMethod *method;
+    enum mth_scope scope;
+};
+
+static struct hash_entry cache[CACHE_SIZE];
+
+static struct RMethod*
+search_method(class, id, origin)
+    struct RClass *class, **origin;
+    ID id;
+{
+    struct RMethod *body;
+    NODE *list;
+
+    while (!st_lookup(class->m_tbl, id, &body)) {
+	class = class->super;
+	if (class == Qnil) return Qnil;
+    }
+
+    if (body->origin)
+	*origin = body->origin;
+    else
+	*origin = class;
+    return body;
+}
+
+NODE*
+rb_get_method_body(class, id, envset, scope)
+    struct RClass *class;
+    ID id;
+    int envset;
+    enum mth_scope scope;
+{
+    int pos, i;
+    int cscope;
+    struct RMethod *method;
+
+    /* is it in the method cache? */
+    pos = EXPR1(class, id) % CACHE_SIZE;
+    if (cache[pos].class != class || cache[pos].mid != id) {
+	/* not in the cache */
+	struct RMethod *body;
+	struct RClass *origin;
+
+	if ((body = search_method(class, id, &origin)) == Qnil) {
+	    return Qnil;
+	}
+	/* store in cache */
+	cache[pos].mid = id;
+	cache[pos].class = class;
+	cache[pos].origin = origin;
+	cache[pos].method = body;
+	cache[pos].scope = body->scope;
+    }
+
+    cscope = cache[pos].scope;
+    method = cache[pos].method;
+    if (cscope == MTH_UNDEF) return Qnil;
+    if (cscope == MTH_FUNC && scope == MTH_METHOD) return Qnil;
+    if (envset) {
+	the_env->last_func = method->id;
+	the_env->last_class = cache[pos].origin;
+    }
+    return method->node;
+}
+
+void
+rb_alias(class, name, def)
+    struct RClass *class;
+    ID name, def;
+{
+    struct RMethod *body;
+
+    if (st_lookup(class->m_tbl, name, &body)) {
+	if (verbose) {
+	    Warning("redefine %s", rb_id2name(name));
+	}
+	unliteralize(body);
+    }
+    body = search_method(class, def, &body);
+    st_insert(class->m_tbl, name, body);
+}
+
+void
+rb_clear_cache(body)
+    struct RMethod *body;
+{
+    int i;
+
+    for (i = 0; i< CACHE_SIZE; i++ ) {
+	if (cache[i].method == body) {
+	    cache[i].class = Qnil;
+	    cache[i].mid = Qnil;
+	}
+    }
+}
+
+void
+rb_clear_cache2(class)
+    struct RClass *class;
+{
+
+    class = class->super;
+    while (class) {
+	int i;
+
+	for (i = 0; i< CACHE_SIZE; i++ ) {
+	    if (cache[i].origin == class) {
+		cache[i].class = Qnil;
+		cache[i].mid = Qnil;
+	    }
+	}
+	class = class->super;
+    }
+}