Cache lookups at megamorphic call sites in optimized code.

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/cha.h"
 #include "vm/dart_entry.h"
@@ skipping 515 matching lines @@
             StubCode::ThreeArgsOptimizedCheckInlineCacheEntryPoint();
         break;
       default:
         UNIMPLEMENTED();
     }
     ExternalLabel target_label("InlineCache", label_address);
     EmitOptimizedInstanceCall(&target_label, ic_data, arguments_descriptor,
                               argument_count, deopt_id, token_pos, locs);
     return;
   }
+
   if (is_optimizing()) {
-    // Megamorphic call requires one argument ICData.
-    ASSERT(ic_data.num_args_tested() == 1);
-    label_address = StubCode::MegamorphicCallEntryPoint();
-  } else {
-    switch (ic_data.num_args_tested()) {
-      case 1:
-        label_address = StubCode::OneArgCheckInlineCacheEntryPoint();
-        break;
-      case 2:
-        label_address = StubCode::TwoArgsCheckInlineCacheEntryPoint();
-        break;
-      case 3:
-        label_address = StubCode::ThreeArgsCheckInlineCacheEntryPoint();
-        break;
-      default:
-        UNIMPLEMENTED();
-    }
+    EmitMegamorphicInstanceCall(ic_data, arguments_descriptor, argument_count,
+                                deopt_id, token_pos, locs);
+    return;
+  }
+
+  switch (ic_data.num_args_tested()) {
+    case 1:
+      label_address = StubCode::OneArgCheckInlineCacheEntryPoint();
+      break;
+    case 2:
+      label_address = StubCode::TwoArgsCheckInlineCacheEntryPoint();
+      break;
+    case 3:
+      label_address = StubCode::ThreeArgsCheckInlineCacheEntryPoint();
+      break;
+    default:
+      UNIMPLEMENTED();
   }
   ExternalLabel target_label("InlineCache", label_address);
   EmitInstanceCall(&target_label, ic_data, arguments_descriptor, argument_count,
                    deopt_id, token_pos, locs);
 }
 
 
 void FlowGraphCompiler::GenerateStaticCall(intptr_t deopt_id,
                                            intptr_t token_pos,
                                            const Function& function,
@@ skipping 460 matching lines @@
     const AbstractTypeArguments& type_arguments =
         AbstractTypeArguments::Handle(type.arguments());
     const bool is_raw_type = type_arguments.IsNull() ||
         type_arguments.IsRaw(type_arguments.Length());
     return is_raw_type;
   }
   return true;
 }
 
 }  // namespace dart