Dummy receiver optimization

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

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 /**
  * This phase simplifies interceptors in multiple ways:
  *
  * 1) If the interceptor is for an object whose type is known, it
@@ skipping 168 matching lines @@
     // use only the selector of that instruction.
     if (dominator != null) {
       interceptedClasses =
             backend.getInterceptedClassesOn(dominator.selector.name);
 
       // If we found that we need number, we must still go through all
       // uses to check if they require int, or double.
       if (interceptedClasses.contains(backend.jsNumberClass)
           && !(interceptedClasses.contains(backend.jsDoubleClass)
                || interceptedClasses.contains(backend.jsIntClass))) {
-        for (var user in node.usedBy) {
+        for (HInstruction user in node.usedBy) {
           if (user is! HInvoke) continue;
           Set<ClassElement> intercepted =
               backend.getInterceptedClassesOn(user.selector.name);
           if (intercepted.contains(backend.jsIntClass)) {
             interceptedClasses.add(backend.jsIntClass);
           }
           if (intercepted.contains(backend.jsDoubleClass)) {
             interceptedClasses.add(backend.jsDoubleClass);
           }
         }
       }
     } else {
       interceptedClasses = new Set<ClassElement>();
-      for (var user in node.usedBy) {
+      for (HInstruction user in node.usedBy) {
         if (user is HIs) {
           // Is-checks can be performed on any intercepted class.
           interceptedClasses.addAll(backend.interceptedClasses);
           break;
         }
         if (user is! HInvoke) continue;
         // We don't handle escaping interceptors yet.
         interceptedClasses.addAll(
             backend.getInterceptedClassesOn(user.selector.name));
       }
     }
 
     HInstruction receiver = node.receiver;
     if (canUseSelfForInterceptor(receiver, interceptedClasses)) {
+      List<HInstruction> users = node.usedBy.toList();
       node.block.rewrite(node, receiver);
+
+      // Replace occurences of the receiver in invocations with a dummy receiver
+      // if the selector matches only methods that ignore the receiver.
+      JavaScriptBackend backend = compiler.backend;
+      for (HInstruction user in users) {
+        if (user is HInvokeDynamic) {
+          HInvokeDynamic invoke = user;
+          if (invoke.getDartReceiver(compiler) == receiver
+              && !backend.isInterceptedMixinSelector(invoke.selector)) {
+            // [receiver] might not be the direct input since `node.receiver`
+            // looks through type conversion nodes like [TypeKnown].
+            HInstruction immediateReceiver = invoke.inputs[1];
+            Constant constant = new DummyReceiverConstant(
+                immediateReceiver.instructionType);
+            HConstant dummy = graph.addConstant(constant, compiler);
+            immediateReceiver.usedBy.remove(invoke);
+            invoke.inputs[1] = dummy;
+            dummy.usedBy.add(invoke);
+          }
+        }
+      }
       return false;
     }
 
     // Try computing a constant interceptor.
     HInstruction constantInterceptor =
         tryComputeConstantInterceptor(receiver, interceptedClasses);
     if (constantInterceptor != null) {
       node.block.rewrite(node, constantInterceptor);
       return false;
     }
@@ skipping 51 matching lines @@
       instruction = new HInvokeDynamicMethod(
           selector, inputs, node.instructionType, true);
     }
 
     HBasicBlock block = node.block;
     block.addAfter(node, instruction);
     block.rewrite(node, instruction);
     return true;
   }
 }