Support native float subclasses in CastToJavaDoubleNode

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/util/CastToJavaDoubleNode.java

@@ -43,19 +43,23 @@
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
 import com.oracle.graal.python.builtins.modules.MathGuards;
 import com.oracle.graal.python.builtins.objects.cext.PythonAbstractNativeObject;
+import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.FromNativeSubclassNode;
+import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.ImportCAPISymbolNode;
+import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.ToSulongNode;
 import com.oracle.graal.python.builtins.objects.ints.PInt;
 import com.oracle.graal.python.nodes.PNodeWithContext;
 import com.oracle.graal.python.nodes.PRaiseNode;
 import com.oracle.graal.python.nodes.classes.IsSubtypeNode;
 import com.oracle.graal.python.nodes.object.InlinedGetClassNode.GetPythonObjectClassNode;
 import com.oracle.graal.python.nodes.truffle.PythonArithmeticTypes;
-import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.dsl.Bind;
 import com.oracle.truffle.api.dsl.Cached;
 import com.oracle.truffle.api.dsl.GenerateUncached;
 import com.oracle.truffle.api.dsl.ImportStatic;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.dsl.TypeSystemReference;
+import com.oracle.truffle.api.interop.InteropLibrary;
+import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
 
 /**
@@ -89,10 +93,12 @@ static double toDouble(PInt x,
     static double doNativeObject(PythonAbstractNativeObject x,
                     @Bind("this") Node node,
                     @Cached GetPythonObjectClassNode getClassNode,
-                    @Cached IsSubtypeNode isSubtypeNode) {
+                    @Cached IsSubtypeNode isSubtypeNode,
+                    @CachedLibrary(limit = "1") InteropLibrary interopLibrary,
+                    @Cached ToSulongNode toSulongNode,
+                    @Cached ImportCAPISymbolNode importSymNode) {
         if (isSubtypeNode.execute(getClassNode.execute(node, x), PythonBuiltinClassType.PFloat)) {
-            CompilerDirectives.transferToInterpreter();
-            throw new RuntimeException("casting a native float object to a Java double is not implemented yet");
+            return FromNativeSubclassNode.readObFval(x, toSulongNode, interopLibrary, importSymNode);
         }
         // the object's type is not a subclass of 'float'
         throw CannotCastException.INSTANCE;