Add support to for native JsType arrays.

Java arrays stash some properties to be have to perform casts and array
store checks. Storing properties can be avoided for native JsType arrays,
which in this patch are represented as plan JavaScript arrays.

Change-Id: I63e7dcfa606dd639819f3bc17fd31d16f759cf12

dev/core/src/com/google/gwt/dev/jjs/ast/JProgram.java

@@ -485,7 +485,10 @@ public EnumSet<DispatchType> getDispatchType(JReferenceType type) {
     }
 
     if (type.isArrayType()) {
-      return EnumSet.of(DispatchType.JAVA_ARRAY);
+      // A variable of type Object[] could contain an instance of native JsType[], the latter
+      // is treated as a JSO for devirtualization purposes.
+      // TODO(rluble): maybe it should not be treated as a JSO, think .toString().
+      return EnumSet.of(DispatchType.JSO, DispatchType.JAVA_ARRAY);
     }
     EnumSet<DispatchType> dispatchSet = EnumSet.noneOf(DispatchType.class);
     DispatchType dispatchType = getRepresentedAsNativeTypesDispatchMap().get(type);
@@ -1134,6 +1137,15 @@ public void initTypeInfo(Map<JReferenceType, JCastMap> castMapForType) {
     }
   }
 
+  public boolean isUntypedArrayType(JType type) {
+    if (!type.isArrayType()) {
+      return false;
+    }
+
+    JArrayType arrayType = (JArrayType) type;
+    return arrayType.getLeafType().isJsNative();
+  }
+
   public boolean isJavaLangString(JType type) {
     assert type != null;
     return type.getUnderlyingType() == typeString;

dev/core/src/com/google/gwt/dev/jjs/ast/RuntimeConstants.java

@@ -27,13 +27,14 @@ public class RuntimeConstants {
   public static final String ARRAY_GET_CLASS_LITERAL_FOR_ARRAY = "Array.getClassLiteralForArray";
   public static final String ARRAY_INITIALIZE_UNIDIMENSIONAL_ARRAY = "Array.initUnidimensionalArray";
   public static final String ARRAY_INITIALIZE_MULTIDIMENSIONAL_ARRAY = "Array.initMultidimensionalArray";
-  public static final String ARRAY_STAMP_JAVA_TYPE_INFO = "Array.stampJavaTypeInfo";
+  public static final String ARRAY_NEW_ARRAY = "Array.newArray";
   public static final String ARRAY_SET_CHECK = "Array.setCheck";
+  public static final String ARRAY_STAMP_JAVA_TYPE_INFO = "Array.stampJavaTypeInfo";
+  public static final String ARRAY_IS_JAVA_ARRAY = "Array.isJavaArray";
 
   public static final String CAST_CHAR_TO_STRING = "Cast.charToString";
   public static final String CAST_HAS_JAVA_OBJECT_VIRTUAL_DISPATCH =
       "Cast.hasJavaObjectVirtualDispatch";
-  public static final String CAST_IS_JAVA_ARRAY = "Cast.isJavaArray";
   public static final String CAST_THROW_CLASS_CAST_EXCEPTION_UNLESS_NULL
       = "Cast.throwClassCastExceptionUnlessNull";
 

dev/core/src/com/google/gwt/dev/jjs/ast/js/JsonArray.java

@@ -17,8 +17,8 @@
 
 import com.google.gwt.dev.jjs.SourceInfo;
 import com.google.gwt.dev.jjs.ast.Context;
-import com.google.gwt.dev.jjs.ast.JClassType;
 import com.google.gwt.dev.jjs.ast.JExpression;
+import com.google.gwt.dev.jjs.ast.JType;
 import com.google.gwt.dev.jjs.ast.JVisitor;
 import com.google.gwt.thirdparty.guava.common.collect.Lists;
 
@@ -30,17 +30,19 @@
  */
 public class JsonArray extends JExpression {
 
-  private final List<JExpression> expressions;
+  private final List<JExpression> expressions = Lists.newArrayList();
 
-  private JClassType arrayType;
+  // JsonArray objects are typed as either JavaScriptObject, Object[], or native JsType[] depending
+  // on the use.
+  private JType arrayType;
 
-  public JsonArray(SourceInfo sourceInfo, JClassType arrayType, Iterable<JExpression> expressions) {
+  public JsonArray(SourceInfo sourceInfo, JType arrayType, List<JExpression> expressions) {
     super(sourceInfo);
     this.arrayType = arrayType;
-    this.expressions = Lists.newArrayList(expressions);
+    this.expressions.addAll(expressions);
   }
 
-  public JsonArray(SourceInfo sourceInfo, JClassType arrayType, JExpression... expressions) {
+  public JsonArray(SourceInfo sourceInfo, JType arrayType, JExpression... expressions) {
     this(sourceInfo, arrayType, Arrays.asList(expressions));
   }
 
@@ -49,7 +51,7 @@ public List<JExpression> getExpressions() {
   }
 
   @Override
-  public JClassType getType() {
+  public JType getType() {
     return arrayType;
   }
 
@@ -66,9 +68,9 @@ public boolean hasSideEffects() {
   /**
    * Resolve an external references during AST stitching.
    */
-  public void resolve(JClassType jsoType) {
-    assert jsoType.replaces(this.arrayType);
-    this.arrayType = jsoType;
+  public void resolve(JType arrayType) {
+    assert arrayType.replaces(this.arrayType);
+    this.arrayType = arrayType;
   }
 
   @Override

dev/core/src/com/google/gwt/dev/jjs/impl/ArrayNormalizer.java

@@ -37,6 +37,7 @@
 import com.google.gwt.dev.jjs.ast.js.JsonArray;
 
 import java.util.Collections;
+import java.util.List;
 
 /**
  * Replace array accesses and instantiations with calls to the Array class.
@@ -78,11 +79,25 @@ public void endVisit(JBinaryOperation x, Context ctx) {
     public void endVisit(JNewArray x, Context ctx) {
       JArrayType type = x.getArrayType();
 
-      if (x.getInitializers() != null) {
+      List<JExpression> initializers = x.getInitializers();
+      if (initializers != null) {
+        JsonArray initializerArray = new JsonArray(x.getSourceInfo(), type, initializers);
+        if (program.isUntypedArrayType(type)) {
+          ctx.replaceMe(initializerArray);
+          return;
+        }
         ctx.replaceMe(createArrayFromInitializers(x, type));
         return;
       }
 
+      if (program.isUntypedArrayType(type) && type.getDims() == 1) {
+          // Create a plain array.
+        ctx.replaceMe(new JMethodCall(x.getSourceInfo(), null,
+            program.getIndexedMethod(RuntimeConstants.ARRAY_NEW_ARRAY),
+            x.getDimensionExpressions().get(0)));
+        return;
+      }
+
       int suppliedDimensions = x.getDimensionExpressions().size();
       assert (suppliedDimensions >= 1);
 

dev/core/src/com/google/gwt/dev/jjs/impl/Devirtualizer.java

@@ -225,7 +225,7 @@ public static void exec(JProgram program) {
   private final JMethod hasJavaObjectVirtualDispatch;
 
   /**
-   * Contains the Cast.instanceofArray method.
+   * Contains the Cast.isJavaArray method.
    */
   private final JMethod isJavaArray;
 
@@ -284,7 +284,7 @@ private Devirtualizer(JProgram program) {
 
     this.hasJavaObjectVirtualDispatch =
         program.getIndexedMethod(RuntimeConstants.CAST_HAS_JAVA_OBJECT_VIRTUAL_DISPATCH);
-    this.isJavaArray = program.getIndexedMethod(RuntimeConstants.CAST_IS_JAVA_ARRAY);
+    this.isJavaArray = program.getIndexedMethod(RuntimeConstants.ARRAY_IS_JAVA_ARRAY);
     // TODO: consider turning on null checks for "this"?
     // However, for JSO's there is existing code that relies on nulls being okay.
     this.converter = new StaticCallConverter(program, false);
@@ -479,7 +479,7 @@ private JMethod getOrCreateDevirtualMethod(JMethod method) {
     // Synthesize the dispatch at a single conditional doing the checks in this order.
     //   isString(obj) ? dispatchToString : (
     //     isRegularJavaObject(obj) ? obj.method : (
-    //       isArray(obj) ?
+    //       isJavaArray(obj) ?
     //         dispatchToArray :
     //         dispatchToJSO
     //     )

dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java

@@ -2912,14 +2912,20 @@ private JStringLiteral getStringLiteral(SourceInfo info, String string) {
       return new JStringLiteral(info, intern(string), javaLangString);
     }
 
-    /**
-     * TODO(scottb): move to UnifyAst and only for non-abstract classes.
-     */
     private void implementGetClass(JDeclaredType type) {
+      // TODO(rluble): Object.getClass() should be final our JRE, when that is done, GwtAstBuilder
+      // creates overrides for convenience and should unmark Object.getClass as final for
+      // consistency.
       JMethod method = type.getMethods().get(GET_CLASS_METHOD_INDEX);
-      assert (GwtAstBuilder.GET_CLASS_METHOD_NAME.equals(method.getName()));
+      assert (GET_CLASS_METHOD_NAME.equals(method.getName()));
       SourceInfo info = method.getSourceInfo();
-      JjsUtils.replaceMethodBody(method, new JClassLiteral(info, type));
+      if (type.isJsoType()) {
+        // return Cast.getClass(this)
+        JjsUtils.replaceMethodBody(method,
+            new JMethodCall(info, null, CAST_GET_CLASS_METHOD, new JThisRef(info, type)));
+      } else {
+        JjsUtils.replaceMethodBody(method, new JClassLiteral(info, type));
+      }
     }
 
     private JDeclarationStatement makeDeclaration(SourceInfo info, JLocal local,
@@ -3795,6 +3801,10 @@ private boolean isBinaryBinding(ReferenceBinding binding) {
       JMethod.getExternalizedMethod("com.google.gwt.lang.Exceptions",
       "safeClose(Ljava/lang/AutoCloseable;Ljava/lang/Throwable;)Ljava/lang/Throwable;", true);
 
+  private static JMethod CAST_GET_CLASS_METHOD =
+      JMethod.getExternalizedMethod("com.google.gwt.lang.Cast",
+      "getClass(Ljava/lang/Object;)Ljava/lang/Class;", true);
+
   private List<JDeclaredType> processImpl() {
     CompilationUnitDeclaration cud = curCud.cud;
     if (cud.types == null) {

dev/core/src/com/google/gwt/dev/jjs/impl/ImplementCastsAndTypeChecks.java

@@ -224,6 +224,7 @@ private TypeCategory determineTypeCategoryForType(JReferenceType type) {
 
     assert EnumSet.of(TypeCategory.TYPE_JSO,
         TypeCategory.TYPE_JAVA_OBJECT_OR_JSO,
+        TypeCategory.TYPE_NATIVE_ARRAY,
         TypeCategory.TYPE_JAVA_LANG_OBJECT,
         TypeCategory.TYPE_JAVA_LANG_STRING,
         TypeCategory.TYPE_JAVA_LANG_DOUBLE,

dev/core/src/com/google/gwt/dev/jjs/impl/ReplaceGetClassOverrides.java

@@ -80,7 +80,8 @@ private boolean isGetClassMethod(JMethod method) {
 
     private boolean isGetClassDevirtualized(JType type) {
       return type == program.getJavaScriptObject()
-          || program.getRepresentedAsNativeTypes().contains(type);
+          || program.getRepresentedAsNativeTypes().contains(type)
+          || type.isJsNative();
     }
   }
 }

dev/core/src/com/google/gwt/dev/jjs/impl/TypeCategory.java

@@ -41,6 +41,7 @@ public enum TypeCategory {
   TYPE_JAVA_OBJECT,
   TYPE_JAVA_OBJECT_OR_JSO("AllowJso"),
   TYPE_JSO("Jso"),
+  TYPE_NATIVE_ARRAY("NativeArray"),
   TYPE_JAVA_LANG_OBJECT("AllowJso"),
   TYPE_JAVA_LANG_STRING("String"),
   TYPE_JAVA_LANG_DOUBLE("Double"),
@@ -54,11 +55,11 @@ public enum TypeCategory {
 
   private final String castInstanceOfQualifier;
 
-  private TypeCategory() {
+  TypeCategory() {
     this("");
   }
 
-  private TypeCategory(String castInstanceOfQualifier) {
+  TypeCategory(String castInstanceOfQualifier) {
     this.castInstanceOfQualifier = castInstanceOfQualifier;
   }
 
@@ -82,7 +83,9 @@ public static TypeCategory typeCategoryForType(JType type, JProgram program) {
 
     assert type instanceof JReferenceType;
     type = type.getUnderlyingType();
-    if (type == program.getTypeJavaLangObject()) {
+    if (program.isUntypedArrayType(type)) {
+      return TypeCategory.TYPE_NATIVE_ARRAY;
+    } else if (type == program.getTypeJavaLangObject()) {
       return TypeCategory.TYPE_JAVA_LANG_OBJECT;
     } else if (program.getRepresentedAsNativeTypesDispatchMap().containsKey(type)) {
       return program.getRepresentedAsNativeTypesDispatchMap().get(type).getTypeCategory();

dev/core/super/com/google/gwt/dev/jjs/intrinsic/com/google/gwt/lang/Array.java

@@ -32,23 +32,34 @@ public final class Array {
   private static final int TYPE_JAVA_OBJECT = 0;
   private static final int TYPE_JAVA_OBJECT_OR_JSO = 1;
   private static final int TYPE_JSO = 2;
-  private static final int TYPE_JAVA_LANG_OBJECT = 3;
-  private static final int TYPE_JAVA_LANG_STRING = 4;
-  private static final int TYPE_JAVA_LANG_DOUBLE = 5;
-  private static final int TYPE_JAVA_LANG_BOOLEAN = 6;
-  private static final int TYPE_JS_NATIVE = 7;
-  private static final int TYPE_JS_NATIVE_PROTOTYPE = 8;
-  private static final int TYPE_JS_FUNCTION = 9;
-  private static final int TYPE_PRIMITIVE_LONG = 10;
-  private static final int TYPE_PRIMITIVE_NUMBER = 11;
-  private static final int TYPE_PRIMITIVE_BOOLEAN = 12;
+  private static final int TYPE_NATIVE_ARRAYs = 3;
+  private static final int TYPE_JAVA_LANG_OBJECT = 4;
+  private static final int TYPE_JAVA_LANG_STRING = 5;
+  private static final int TYPE_JAVA_LANG_DOUBLE = 6;
+  private static final int TYPE_JAVA_LANG_BOOLEAN = 7;
+  private static final int TYPE_JS_NATIVE = 8;
+  private static final int TYPE_JS_UNKNOWN_NATIVE = 9;
+  private static final int TYPE_JS_FUNCTION = 10;
+  private static final int TYPE_PRIMITIVE_LONG = 11;
+  private static final int TYPE_PRIMITIVE_NUMBER = 12;
+  private static final int TYPE_PRIMITIVE_BOOLEAN = 13;
 
   public static <T> T[] stampJavaTypeInfo(Object array, T[] referenceType) {
-    stampJavaTypeInfo(referenceType.getClass(), Util.getCastableTypeMap(referenceType),
-        Array.getElementTypeId(referenceType), Array.getElementTypeCategory(referenceType), array);
+    if (Array.getElementTypeCategory(referenceType) != TYPE_JS_UNKNOWN_NATIVE) {
+      stampJavaTypeInfo(referenceType.getClass(), Util.getCastableTypeMap(referenceType),
+          Array.getElementTypeId(referenceType),
+          Array.getElementTypeCategory(referenceType), array);
+    }
     return Array.asArray(array);
   }
 
+  /**
+   * Returns an untyped uninitialized array.
+   */
+  static native Object[] newArray(int size) /*-{
+    return new Array(size);
+  }-*/;
+
   /**
    * Creates an array like "new T[a][b][c][][]" by passing in a native JSON
    * array, [a, b, c].
@@ -71,8 +82,10 @@ public static Object initUnidimensionalArray(Class<?> leafClassLiteral,
       JavaScriptObject castableTypeMap, JavaScriptObject elementTypeId, int length,
       int elementTypeCategory, int dimensions) {
     Object result = initializeArrayElementsWithDefaults(elementTypeCategory, length);
-    stampJavaTypeInfo(getClassLiteralForArray(leafClassLiteral, dimensions), castableTypeMap,
-        elementTypeId, elementTypeCategory, result);
+    if (elementTypeCategory != TYPE_JS_UNKNOWN_NATIVE) {
+      stampJavaTypeInfo(getClassLiteralForArray(leafClassLiteral, dimensions), castableTypeMap,
+          elementTypeId, elementTypeCategory, result);
+    }
     return result;
   }
 
@@ -222,8 +235,10 @@ private static Object initMultidimensionalArray(Class<?> leafClassLiteral,
     int elementTypeCategory = isLastDimension ? leafElementTypeCategory : TYPE_JAVA_OBJECT;
 
     Object result = initializeArrayElementsWithDefaults(elementTypeCategory, length);
-    stampJavaTypeInfo(getClassLiteralForArray(leafClassLiteral, count - index),
-        castableTypeMapExprs[index], elementTypeIds[index], elementTypeCategory, result);
+    if (leafElementTypeCategory != TYPE_JS_UNKNOWN_NATIVE) {
+      stampJavaTypeInfo(getClassLiteralForArray(leafClassLiteral, count - index),
+          castableTypeMapExprs[index], elementTypeIds[index], elementTypeCategory, result);
+    }
 
     if (!isLastDimension) {
       // Recurse to next dimension.
@@ -247,9 +262,12 @@ static <T> Class<T> getClassLiteralForArray(Class<?> clazz , int dimensions) {
   }
 
   private static native int getElementTypeCategory(Object array) /*-{
-    return array.__elementTypeCategory$;
+    return array.__elementTypeCategory$ == null
+        ? @Array::TYPE_JS_UNKNOWN_NATIVE
+        : array.__elementTypeCategory$;
   }-*/;
 
+  @HasNoSideEffects
   private static native JavaScriptObject getElementTypeId(Object array) /*-{
     return array.__elementTypeId$;
   }-*/;
@@ -281,6 +299,14 @@ private static native void setElementTypeCategory(Object array, int elementTypeC
     array.__elementTypeCategory$ = elementTypeCategory;
   }-*/;
 
+  /**
+   * Returns true if {@code src} is a Java array.
+   */
+  @HasNoSideEffects
+  static boolean isJavaArray(Object src) {
+    return Cast.isArray(src) && Util.hasTypeMarker(src);
+  }
+
   private Array() {
   }
 }