Move computation of method flags into model.

pkg/compiler/lib/src/js_emitter/program_builder.dart

Index: pkg/compiler/lib/src/js_emitter/program_builder.dart
diff --git a/pkg/compiler/lib/src/js_emitter/program_builder.dart b/pkg/compiler/lib/src/js_emitter/program_builder.dart
index 4e2f55577e1f5162fdeb4978ad9e506d378751da..50ab505001fb58178cce29584ec31777a5abd03e 100644
--- a/pkg/compiler/lib/src/js_emitter/program_builder.dart
+++ b/pkg/compiler/lib/src/js_emitter/program_builder.dart
@@ -266,6 +266,7 @@ class ProgramBuilder {
   ///
   /// Returns a class that contains the fields of a class.
   Class buildClassWithFieldsForTry(ClassElement element) {
+    assert(_compiler.hasIncrementalSupport);
     bool onlyForRti = _task.typeTestRegistry.rtiNeededClasses.contains(element);
 
     List<Field> instanceFields =
@@ -374,10 +375,73 @@ class ProgramBuilder {
     return result;
   }
 
-  Method _buildMethod(FunctionElement element, js.Expression code) {
+  bool _methodNeedsStubs(FunctionElement method) {
+    return !method.functionSignature.optionalParameters.isEmpty;
+  }
+
+  bool _methodCanBeReflected(FunctionElement method) {
+    return backend.isAccessibleByReflection(method) ||
+        // During incremental compilation, we have to assume that reflection
+        // *might* get enabled.
+        _compiler.hasIncrementalSupport;
+  }
+
+  bool _methodCanBeApplied(FunctionElement method) {
+    return _compiler.enabledFunctionApply &&
+        _compiler.world.getMightBePassedToApply(method);
+  }
+
+  // Hack for Try!
+  Method buildMethodForTry(FunctionElement element) {

[floitsch, 2015/01/28 16:10:39]

As discussed: change name.

[herhut, 2015/01/29 10:24:21]

now buildMethodHackForIncrementalCompilation

+    assert(_compiler.hasIncrementalSupport);
+    if (element.isInstanceMember) {
+      js.Expression code = backend.generatedCode[element];
+      return _buildMethod(element, code);
+    } else {
+      return _buildStaticMethod(element);
+    }
+  }
+
+  // TODO(herhut): Why does this get code passed in and statics don't?

[floitsch, 2015/01/28 16:10:39]

Probably just an oversight.

[herhut, 2015/01/29 10:24:21]

Changed.

+  DartMethod _buildMethod(FunctionElement element, js.Expression code) {
     String name = namer.getNameOfInstanceMember(element);
-    // TODO(floitsch): compute `needsTearOff`.
-    return new Method(element, name, code, needsTearOff: false);
+
+    bool canTearOff = false;
+    String tearOffName;
+    bool isClosure = false;
+    bool isNotApplyTarget = !element.isFunction || element.isAccessor;
+
+    final bool needsStubs = _methodNeedsStubs(element);
+    final bool canBeReflected = _methodCanBeReflected(element);
+    final bool canBeApplied = _methodCanBeApplied(element);
+    final bool hasSuperAlias = backend.isAliasedSuperMember(element);
+
+    if (isNotApplyTarget) {
+      canTearOff = false;
+    } else {
+      if (element.enclosingClass.isClosure) {
+        canTearOff = false;
+        isClosure = true;
+      } else {
+        // Careful with operators.
+        canTearOff = universe.hasInvokedGetter(element, _compiler.world) ||
+            (canBeReflected && !element.isOperator);
+        assert(canTearOff ||
+               !universe.methodsNeedingSuperGetter.contains(element));
+        tearOffName = namer.getterName(element);
+      }
+    }
+
+    if (canTearOff) {
+      assert(invariant(element, !element.isGenerativeConstructor));
+      assert(invariant(element, !element.isGenerativeConstructorBody));
+      assert(invariant(element, !element.isConstructor));
+    }
+
+    return new InstanceMethod(element, name, code, needsTearOff: canTearOff,
+        tearOffName: tearOffName, isClosure: isClosure,
+        hasSuperAlias: hasSuperAlias, canBeApplied: canBeApplied,
+        canBeReflected: canBeReflected, needsStubs: needsStubs);
   }
 
   /// Builds a stub method.
@@ -386,8 +450,7 @@ class ProgramBuilder {
   /// attribution.
   Method _buildStubMethod(String name, js.Expression code,
                           {Element element}) {
-    // TODO(floitsch): compute `needsTearOff`.
-    return new StubMethod(name, code, needsTearOff: false, element: element);
+    return new StubMethod(name, code, element: element);
   }
 
   // The getInterceptor methods directly access the prototype of classes.
@@ -418,6 +481,7 @@ class ProgramBuilder {
       Set<ClassElement> classes = specializedGetInterceptors[name];
       js.Expression code = stubGenerator.generateGetInterceptorMethod(classes);
       // TODO(floitsch): compute `needsTearOff`.
+      // TODO(herhut): Can these actually ever be torn off?

[floitsch, 2015/01/28 16:10:39]

Until we find a case where it can be, let's just remove it and assume that "no".

[herhut, 2015/01/29 10:24:21]

Done.

       return new StaticStubMethod(name, holder, code, needsTearOff: false);
     });
   }
@@ -486,12 +550,25 @@ class ProgramBuilder {
     String name = namer.getNameOfMember(element);
     String holder = namer.globalObjectFor(element);
     js.Expression code = backend.generatedCode[element];
-    bool needsTearOff =
-        universe.staticFunctionsNeedingGetter.contains(element);
-    // TODO(floitsch): add tear-off name: namer.getStaticClosureName(element).
+
+    final bool isNotApplyTarget = !element.isConstructor && !element.isAccessor;
+    final bool needsStubs = _methodNeedsStubs(element);
+    final bool canBeApplied = _methodCanBeApplied(element);
+    final bool canBeReflected = _methodCanBeReflected(element);
+
+    final bool needsTearOff = isNotApplyTarget && (canBeReflected ||
+         universe.staticFunctionsNeedingGetter.contains(element));
+
+    final String tearOffName =
+        needsTearOff ? namer.getStaticClosureName(element) : null;
+
     return new StaticMethod(element,
                             name, _registry.registerHolder(holder), code,
-                            needsTearOff: needsTearOff);
+                            needsTearOff: needsTearOff,
+                            tearOffName: tearOffName,
+                            canBeApplied: canBeApplied,
+                            canBeReflected: canBeReflected,
+                            needsStubs: needsStubs);
   }
 
   void _registerConstants(OutputUnit outputUnit,