Add a shape flag to signify an object has no dict

Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/object/PythonObject.java

@@ -33,6 +33,7 @@
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
 import com.oracle.graal.python.builtins.objects.PNone;
 import com.oracle.graal.python.builtins.objects.PythonAbstractObject;
+import com.oracle.graal.python.builtins.objects.dict.PDict;
 import com.oracle.graal.python.builtins.objects.type.PythonBuiltinClass;
 import com.oracle.graal.python.builtins.objects.type.PythonManagedClass;
 import com.oracle.graal.python.nodes.HiddenAttributes;
@@ -47,13 +48,20 @@
 
 public class PythonObject extends PythonAbstractObject {
     public static final HiddenKey DICT = HiddenAttributes.DICT;
-    public static final byte CLASS_CHANGED_FLAG = 1;
-    public static final byte HAS_SLOTS_BUT_NO_DICT_FLAG = 2;
+    public static final byte CLASS_CHANGED_FLAG = 0b1;
+    /**
+     * Indicates that the object doesn't allow {@code __dict__}, but may have slots
+     */
+    public static final byte HAS_SLOTS_BUT_NO_DICT_FLAG = 0b10;
     /**
      * Indicates that the shape has some properties that may contain {@link PNone#NO_VALUE} and
      * therefore the shape itself is not enough to resolve any lookups.
      */
-    public static final byte HAS_NO_VALUE_PROPERTIES = 4;
+    public static final byte HAS_NO_VALUE_PROPERTIES = 0b100;
+    /**
+     * Indicates that the object has a dict in the form of an actual dictionary
+     */
+    public static final byte HAS_MATERIALIZED_DICT = 0b1000;
 
     private final Object initialPythonClass;
 
@@ -85,6 +93,11 @@ public void setPythonClass(Object cls, DynamicObjectLibrary dylib) {
         dylib.put(this, CLASS, cls);
     }
 
+    public void setDict(DynamicObjectLibrary dylib, PDict dict) {
+        dylib.setShapeFlags(this, dylib.getShapeFlags(this) | HAS_MATERIALIZED_DICT);
+        dylib.put(this, DICT, dict);
+    }
+
     public Object getInitialPythonClass() {
         return initialPythonClass;
     }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/type/PythonClass.java

@@ -230,6 +230,7 @@ public void setMRO(PythonAbstractClass[] mro, PythonLanguage language) {
     }
 
     public void setDictHiddenProp(DynamicObjectLibrary dylib, BranchProfile hasMroShapeProfile, Object value) {
+        dylib.setShapeFlags(this, dylib.getShapeFlags(this) | HAS_MATERIALIZED_DICT);
         dylib.put(this, DICT, value);
         if (mroShapeSubTypes != null) {
             hasMroShapeProfile.enter();

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/object/GetDictIfExistsNode.java

@@ -60,13 +60,29 @@
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.object.DynamicObjectLibrary;
+import com.oracle.truffle.api.object.Shape;
 
 @GenerateUncached
 public abstract class GetDictIfExistsNode extends PNodeWithContext {
     public abstract PDict execute(Object object);
 
     public abstract PDict execute(PythonObject object);
 
+    @Specialization(guards = {"object.getShape() == cachedShape", "hasNoDict(cachedShape)"}, limit = "1")
+    static PDict getNoDictCachedShape(@SuppressWarnings("unused") PythonObject object,
+                    @SuppressWarnings("unused") @Cached("object.getShape()") Shape cachedShape) {
+        return null;
+    }
+
+    @Specialization(guards = "hasNoDict(object.getShape())", replaces = "getNoDictCachedShape")
+    static PDict getNoDict(@SuppressWarnings("unused") PythonObject object) {
+        return null;
+    }
+
+    protected static boolean hasNoDict(Shape shape) {
+        return (shape.getFlags() & PythonObject.HAS_MATERIALIZED_DICT) == 0;
+    }
+
     @Specialization(guards = {"object == cached", "dictIsConstant(cached)", "dict != null"}, assumptions = "singleContextAssumption()", limit = "1")
     static PDict getConstant(@SuppressWarnings("unused") PythonObject object,
                     @SuppressWarnings("unused") @Cached(value = "object", weak = true) PythonObject cached,

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/object/SetDictNode.java

@@ -67,7 +67,7 @@ static void doPythonClass(PythonClass object, PDict dict,
     @Fallback
     static void doPythonObjectNotClass(PythonObject object, PDict dict,
                     @Shared("dylib") @CachedLibrary(limit = "4") DynamicObjectLibrary dylib) {
-        dylib.put(object, PythonObject.DICT, dict);
+        object.setDict(dylib, dict);
     }
 
     public static SetDictNode create() {