Lazy allocation of HashMap for VMHash storage on JVM.

Raku · Sep 24, 2013 · f7c396a · f7c396a
1 parent 601b8e9
commit f7c396a
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Showing 2 changed files with 9 additions and 3 deletions.
diff --git a/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/VMHash.java b/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/VMHash.java
@@ -23,7 +23,7 @@ public SixModelObject type_object_for(ThreadContext tc, SixModelObject HOW) {
     public SixModelObject allocate(ThreadContext tc, STable st) {
         VMHashInstance obj = new VMHashInstance();
         obj.st = st;
-        obj.storage = new HashMap<String, SixModelObject>();
+        obj.storage = VMHashInstance.EMPTY_MAP;
         return obj;
     }
 
@@ -34,7 +34,7 @@ public StorageSpec get_value_storage_spec(ThreadContext tc, STable st) {
     public SixModelObject deserialize_stub(ThreadContext tc, STable st) {
         VMHashInstance obj = new VMHashInstance();
         obj.st = st;
-        obj.storage = new HashMap<String, SixModelObject>();
+        obj.storage = VMHashInstance.EMPTY_MAP;
         return obj;
     }
 

diff --git a/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/VMHashInstance.java b/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/VMHashInstance.java
@@ -6,13 +6,19 @@
 import org.perl6.nqp.sixmodel.SixModelObject;
 
 public class VMHashInstance extends SixModelObject {
+    public static final HashMap<String, SixModelObject> EMPTY_MAP = 
+            new HashMap<String, SixModelObject>();
+
     public HashMap<String, SixModelObject> storage;
-    
+
     public SixModelObject at_key_boxed(ThreadContext tc, String key) {
         return storage.get(key);
     }
 
     public void bind_key_boxed(ThreadContext tc, String key, SixModelObject value) {
+        if (storage == VMHashInstance.EMPTY_MAP) {
+            storage = new HashMap<String, SixModelObject>();
+        }
         storage.put(key, value);
     }