[svn:parrot] r38823 - in trunk: lib/Parrot/Pmc2c src/pmc

[chromatic at svn.parrot.org]

Author: chromatic
Date: Sat May 16 10:45:28 2009
New Revision: 38823
URL: https://trac.parrot.org/parrot/changeset/38823

Log:
[PMC] Modified PMC generator to skip the isa_hash in the case where the PMC has
no superclass besides itself.  This allows the appropriate isa and isa_pmc
VTABLE entries to perform a simple exact match instead of the comparatively
expensive hash lookup for type equivalence.

Modified:
   trunk/lib/Parrot/Pmc2c/PMCEmitter.pm
   trunk/src/pmc/default.pmc
   trunk/src/pmc/pmcproxy.pmc

Modified: trunk/lib/Parrot/Pmc2c/PMCEmitter.pm
==============================================================================
--- trunk/lib/Parrot/Pmc2c/PMCEmitter.pm	Sat May 16 10:35:31 2009	(r38822)
+++ trunk/lib/Parrot/Pmc2c/PMCEmitter.pm	Sat May 16 10:45:28 2009	(r38823)
@@ -619,8 +619,8 @@
 
     my $flags = $self->vtable_flags;
     $cout .= <<"EOC";
-        Hash   * isa_hash;
-        VTABLE * vt        = Parrot_${classname}_get_vtable(interp);
+        Hash    *isa_hash  = NULL;
+        VTABLE  *vt        = Parrot_${classname}_get_vtable(interp);
         vt->base_type      = $enum_name;
         vt->flags          = $flags;
         vt->attribute_defs = attr_defs;
@@ -647,20 +647,26 @@
             string_make(interp, " $provides", @{[length($provides) + 1]}, "ascii",
             PObj_constant_FLAG|PObj_external_FLAG));
 
-        /* set up isa hash */
-        isa_hash = parrot_new_hash(interp);
-        vt->isa_hash     = isa_hash;
 EOC
     }
     else {
         $cout .= <<"EOC";
         vt->whoami       = CONST_STRING_GEN(interp, "$classname");
         vt->provides_str = CONST_STRING_GEN(interp, "$provides");
+EOC
+    }
+
+    if (@isa) {
+        unshift @isa, $classname;
+        $cout .= <<"EOC";
 
-        /* set up isa hash */
         isa_hash         = parrot_new_hash(interp);
         vt->isa_hash     = isa_hash;
 EOC
+    } else {
+        $cout .= <<"EOC";
+        vt->isa_hash     = NULL;
+EOC
     }
 
     for my $k ( keys %extra_vt ) {
@@ -683,7 +689,7 @@
         interp->vtables[entry] = vt;
 EOC
 
-    for my $isa ($classname, @isa) {
+    for my $isa (@isa) {
         $cout .= <<"EOC";
         parrot_hash_put(interp, isa_hash, (void *)(CONST_STRING_GEN(interp, "$isa")), PMCNULL);
 EOC
@@ -729,7 +735,8 @@
 
 EOC
 
-    for my $isa ($classname, @isa) {
+    @isa = $classname unless @isa;
+    for my $isa (@isa) {
         $cout .= <<"EOC";
             VTABLE_push_string(interp, mro, CONST_STRING_GEN(interp, "$isa"));
 EOC

Modified: trunk/src/pmc/default.pmc
==============================================================================
--- trunk/src/pmc/default.pmc	Sat May 16 10:35:31 2009	(r38822)
+++ trunk/src/pmc/default.pmc	Sat May 16 10:45:28 2009	(r38823)
@@ -896,12 +896,19 @@
 */
 
     VTABLE INTVAL isa_pmc(PMC *lookup) {
+       Hash   *isa_hash = SELF->vtable->isa_hash;
+       STRING *pmc_name;
+
         if (PMC_IS_NULL(lookup))
             return 0;
 
+        pmc_name = VTABLE_get_string(interp, lookup);
+
+        if (!isa_hash)
+            return Parrot_str_equal(interp, SELF->vtable->whoami, pmc_name);
+
         /* RT #46665 - walk mro */
-        return parrot_hash_exists(INTERP, SELF->vtable->isa_hash,
-                (void *)VTABLE_get_string(interp, lookup));
+        return parrot_hash_exists(INTERP, isa_hash, (void *)pmc_name);
     }
 
 /*
@@ -918,6 +925,9 @@
 
     VTABLE INTVAL isa(STRING *_class) {
         /* RT #46665 - walk mro */
+        if (!SELF->vtable->isa_hash)
+            return Parrot_str_equal(interp, SELF->vtable->whoami, _class);
+
         return parrot_hash_exists(INTERP, SELF->vtable->isa_hash,
                     (void *)_class);
     }

Modified: trunk/src/pmc/pmcproxy.pmc
==============================================================================
--- trunk/src/pmc/pmcproxy.pmc	Sat May 16 10:35:31 2009	(r38822)
+++ trunk/src/pmc/pmcproxy.pmc	Sat May 16 10:45:28 2009	(r38823)
@@ -295,9 +295,16 @@
             return 1;
 
         /* Look in the isa hash. */
-        if (interp->vtables[_proxy->id] != NULL &&
-            parrot_hash_exists(interp, interp->vtables[_proxy->id]->isa_hash, classname))
-            return 1;
+        if (interp->vtables[_proxy->id]) {
+            Hash *isa_hash = interp->vtables[_proxy->id]->isa_hash;
+
+            if (!isa_hash && Parrot_str_equal(interp,
+                     interp->vtables[_proxy->id]->whoami, classname))
+                return 1;
+
+            if (isa_hash && parrot_hash_exists(interp, isa_hash, classname))
+                return 1;
+        }
 
         /* Iterate over all the parents and check if they respond true
          * for 'isa' on the original comparison. */
@@ -334,9 +341,17 @@
             return 1;
 
         /* Look in the isa hash. */
-        if (interp->vtables[_proxy->id] != NULL &&
-            parrot_hash_exists(interp, interp->vtables[_proxy->id]->isa_hash, classname))
-            return 1;
+        if (interp->vtables[_proxy->id]) {
+            Hash *isa_hash = interp->vtables[_proxy->id]->isa_hash;
+
+            if (!isa_hash && Parrot_str_equal(interp,
+                     interp->vtables[_proxy->id]->whoami, classname)) {
+                return 1;
+            }
+
+            if (isa_hash && parrot_hash_exists(interp, isa_hash, classname))
+                return 1;
+        }
 
         return 0;
     }