[PCC] Optimized CS switching invoke.

These checks can go away with threading system improvements, but avoiding this function call which is almost always a do-nothing gives a modest performance improvement to the default case of Sub's invoke.
parrot · Sep 8, 2011 · e934aa8 · e934aa8
1 parent 60c22d7
commit e934aa8
Showing 1 changed file with 44 additions and 45 deletions.
diff --git a/src/packfile/api.c b/src/packfile/api.c
@@ -1794,9 +1794,14 @@ Parrot_switch_to_cs(PARROT_INTERP, ARGIN(PackFile_ByteCode *new_cs), int really)
 
     interp->code               = new_cs;
 
-    Parrot_pcc_set_constants(interp, CURRENT_CONTEXT(interp), really
-                               ? find_constants(interp, new_cs->const_table)
-                               : new_cs->const_table);
+    if (really
+    && (n_interpreters
+    &&  interp->thread_data && interp->thread_data->tid != 0))
+        Parrot_pcc_set_constants(interp, CURRENT_CONTEXT(interp),
+                               find_constants(interp, new_cs->const_table));
+    else
+        Parrot_pcc_set_constants(interp, CURRENT_CONTEXT(interp),
+                               new_cs->const_table);
 
     if (really)
         prepare_for_run(interp);
@@ -1860,55 +1865,49 @@ static PackFile_ConstTable *
 find_constants(PARROT_INTERP, ARGIN(PackFile_ConstTable *ct))
 {
     ASSERT_ARGS(find_constants)
-    if (!n_interpreters
-    ||  !interp->thread_data
-    ||  interp->thread_data->tid == 0)
-        return ct;
-    else {
-        Hash                 *tables;
-        PackFile_ConstTable  *new_ct;
-
-        PARROT_ASSERT(interp->thread_data);
-
-        if (!interp->thread_data->const_tables) {
-            interp->thread_data->const_tables = Parrot_hash_new_pointer_hash(interp);
-        }
-
-        tables = interp->thread_data->const_tables;
-        new_ct = (PackFile_ConstTable *)Parrot_hash_get(interp, tables, ct);
+    Hash                 *tables;
+    PackFile_ConstTable  *new_ct;
 
-        if (!new_ct) {
-            /* need to construct it */
+    PARROT_ASSERT(interp->thread_data);
 
-            int i;
-
-            new_ct = mem_gc_allocate_zeroed_typed(interp, PackFile_ConstTable);
-
-            new_ct->num.const_count = ct->num.const_count;
-            new_ct->num.constants = mem_gc_allocate_n_zeroed_typed(interp,
-                                        ct->num.const_count, FLOATVAL);
-            memcpy(new_ct->num.constants, ct->num.constants,
-                    ct->num.const_count * sizeof (FLOATVAL));
+    if (!interp->thread_data->const_tables) {
+        interp->thread_data->const_tables = Parrot_hash_new_pointer_hash(interp);
+    }
 
-            new_ct->str.const_count = ct->str.const_count;
-            new_ct->str.constants = mem_gc_allocate_n_zeroed_typed(interp,
-                                        ct->str.const_count, STRING *);
-            memcpy(new_ct->str.constants, ct->str.constants,
-                    ct->str.const_count * sizeof (STRING *));
+    tables = interp->thread_data->const_tables;
+    new_ct = (PackFile_ConstTable *)Parrot_hash_get(interp, tables, ct);
 
-            new_ct->pmc.const_count = ct->pmc.const_count;
-            new_ct->pmc.constants = mem_gc_allocate_n_zeroed_typed(interp,
-                                        ct->pmc.const_count, PMC *);
-            memcpy(new_ct->pmc.constants, ct->pmc.constants,
-                    ct->pmc.const_count * sizeof (PMC *));
-            for (i = 0; i < new_ct->pmc.const_count; ++i)
-                clone_constant(interp, &new_ct->pmc.constants[i]);
+    if (!new_ct) {
+        /* need to construct it */
 
-            Parrot_hash_put(interp, tables, ct, new_ct);
-        }
+        int i;
 
-        return new_ct;
+        new_ct = mem_gc_allocate_zeroed_typed(interp, PackFile_ConstTable);
+
+        new_ct->num.const_count = ct->num.const_count;
+        new_ct->num.constants = mem_gc_allocate_n_zeroed_typed(interp,
+                                    ct->num.const_count, FLOATVAL);
+        memcpy(new_ct->num.constants, ct->num.constants,
+                ct->num.const_count * sizeof (FLOATVAL));
+
+        new_ct->str.const_count = ct->str.const_count;
+        new_ct->str.constants = mem_gc_allocate_n_zeroed_typed(interp,
+                                    ct->str.const_count, STRING *);
+        memcpy(new_ct->str.constants, ct->str.constants,
+                ct->str.const_count * sizeof (STRING *));
+
+        new_ct->pmc.const_count = ct->pmc.const_count;
+        new_ct->pmc.constants = mem_gc_allocate_n_zeroed_typed(interp,
+                                    ct->pmc.const_count, PMC *);
+        memcpy(new_ct->pmc.constants, ct->pmc.constants,
+                ct->pmc.const_count * sizeof (PMC *));
+        for (i = 0; i < new_ct->pmc.const_count; ++i)
+            clone_constant(interp, &new_ct->pmc.constants[i]);
+
+        Parrot_hash_put(interp, tables, ct, new_ct);
     }
+
+    return new_ct;
 }