dart2js cps: Refactor tracking of side effects.

pkg/compiler/lib/src/cps_ir/type_propagation.dart

Index: pkg/compiler/lib/src/cps_ir/type_propagation.dart
diff --git a/pkg/compiler/lib/src/cps_ir/type_propagation.dart b/pkg/compiler/lib/src/cps_ir/type_propagation.dart
index f1944ce5a88217e7debaaf8622e8ea196496396e..1fc027734871785e183c981d280f37406269dc6c 100644
--- a/pkg/compiler/lib/src/cps_ir/type_propagation.dart
+++ b/pkg/compiler/lib/src/cps_ir/type_propagation.dart
@@ -38,6 +38,7 @@ import '../world.dart' show World;
 import 'cps_fragment.dart';
 import 'cps_ir_nodes.dart';
 import 'type_mask_system.dart';
+import 'effects.dart';
 
 class ConstantPropagationLattice {
   final TypeMaskSystem typeSystem;
@@ -1882,7 +1883,19 @@ class TransformingVisitor extends DeepRecursiveVisitor {
     }
   }
 
+  visitInvokeConstructor(InvokeConstructor node) {
+    node.effectFlags =
+        Effects.from(compiler.world.getSideEffectsOfElement(node.target));
+  }
+
   visitInvokeMethodDirectly(InvokeMethodDirectly node) {
+    Element target = node.target;
+    if (target is ConstructorBodyElement) {
+      ConstructorBodyElement constructorBody = target;
+      target = constructorBody.constructor;
+    }
+    node.effectFlags =
+        Effects.from(compiler.world.getSideEffectsOfElement(target));
     TypeMask receiverType = node.dartReceiver.type;
     if (node.callingConvention == CallingConvention.Intercepted &&
         typeSystem.areDisjoint(receiverType, typeSystem.interceptorType)) {
@@ -1906,6 +1919,9 @@ class TransformingVisitor extends DeepRecursiveVisitor {
     TypeMask receiverType = node.dartReceiver.type;
     node.mask = typeSystem.intersection(node.mask, receiverType);
 
+    node.effectFlags = Effects.from(
+        compiler.world.getSideEffectsOfSelector(node.selector, node.mask));
+
     bool canBeNonThrowingCallOnNull =
         selectorsOnNull.contains(node.selector) &&
         receiverType.isNullable;
@@ -1977,6 +1993,8 @@ class TransformingVisitor extends DeepRecursiveVisitor {
   }
 
   visitInvokeStatic(InvokeStatic node) {
+    node.effectFlags = Effects.from(
+        compiler.world.getSideEffectsOfElement(node.target));
     return specializeInternalMethodCall(node);
   }
 
@@ -2276,6 +2294,28 @@ class TransformingVisitor extends DeepRecursiveVisitor {
     return null;
   }
 
+  bool isFinal(Element element) {
+    return element is FunctionElement || // Tear-offs are "final".
+           element is FieldElement && classWorld.fieldNeverChanges(element);
+  }
+
+  visitGetField(GetField node) {
+    node.isFinal = isFinal(node.field);

[Siggi Cherem (dart-lang), 2016/02/17 20:53:24]

since `isFinal(element)` is based only on information we have from earlier on,
could we simply initialize node.isFinal at creation time and make it a final
property?

(at least for GetField, GetStatic, and GetLazyStatic)?

[asgerf, 2016/02/29 12:48:17]

Yeah it's better that way. Done.

+  }
+
+  visitGetStatic(GetStatic node) {
+    node.isFinal = isFinal(node.element);
+  }
+
+  visitGetLazyStatic(GetLazyStatic node) {
+    node.isFinal = isFinal(node.element);
+  }
+
+  visitGetLength(GetLength node) {
+    node.isFinal = typeSystem.isDefinitelyFixedLengthIndexable(
+        node.object.definition.type, allowNull: true);
+  }
+
   visitReadTypeVariable(ReadTypeVariable node) {
     // Pattern match on
     //