Allow intercepted calls to have typed selectors.

sdk/lib/_internal/compiler/implementation/ssa/optimize.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/optimize.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/ssa/optimize.dart	(revision 18140)
+++ sdk/lib/_internal/compiler/implementation/ssa/optimize.dart	(working copy)
@@ -279,6 +279,12 @@
     HInstruction input = node.inputs[1];
     HType type = types[input];
     var interceptor = node.inputs[0];
+
+    if (interceptor.isConstant() && selector.isCall()) {
+      DartType type = types[interceptor].computeType(compiler);
+      node.element = type.element.lookupSelector(selector);
+    }
+
     if (interceptor is !HThis && !type.canBePrimitive()) {
       // If the type can be null, and the intercepted method can be in
       // the object class, keep the interceptor.
@@ -331,6 +337,10 @@
         }
       }
       if (target != null) {
+        // There is a strong dependency between codegen and this

[kasperl, 2013/02/06 07:24:03]

Is this a TODO? It's unclear from the comment whether or not this is a problem
or a feature. The use of the word "should" is also a little bit hard to grasp --
will it go away by itself or is it something we should work on getting rid of?

[ngeoffray, 2013/02/06 08:11:55]

It's kind of a problem. The feature is that we're getting rid of the interceptor
SSA node in the inputs, so the interceptor just becomes dead code.

 The use of the word "should" is also a little bit hard to grasp --
I think we should work getting rid of it. Dependencies like this will come back
and hunt us. We could turn it into a HForeign instead but then the pass that
inserts bounds check (for removeLast) needs to be somehow updated. I hope
inlining will make these problems disappear (for example for removeLast, the
bounds checks becomes explicit, so is the growable check and the call to push).

+        // optimization that the dynamic invoke does not need an
+        // interceptor. Once we start inlining, the dependency should
+        // go away.
         HInvokeDynamicMethod result = new HInvokeDynamicMethod(
             node.selector, node.inputs.getRange(1, node.inputs.length - 1));
         result.element = target;
@@ -812,6 +822,7 @@
 
   void visitInvokeDynamicMethod(HInvokeDynamicMethod node) {
     Element element = node.element;
+    if (node.isInterceptorCall) return;
     if (element != backend.jsArrayRemoveLast) return;
     if (boundsChecked.contains(node)) return;
     insertBoundsCheck(