Remove saving/restoring of the context at function entry.

runtime/vm/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/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 743 matching lines @@
   const LocalVarDescriptors& var_descriptors =
       LocalVarDescriptors::Handle(code.var_descriptors());
   intptr_t var_desc_length =
       var_descriptors.IsNull() ? 0 : var_descriptors.Length();
   String& var_name = String::Handle();
   for (intptr_t i = 0; i < var_desc_length; i++) {
     var_name = var_descriptors.GetName(i);
     RawLocalVarDescriptors::VarInfo var_info;
     var_descriptors.GetInfo(i, &var_info);
     const int8_t kind = var_info.kind();
-    if (kind == RawLocalVarDescriptors::kSavedEntryContext) {
-      OS::Print("  saved caller's CTX reg offset %d\n", var_info.index());
-    } else if (kind == RawLocalVarDescriptors::kSavedCurrentContext) {
+    if (kind == RawLocalVarDescriptors::kSavedCurrentContext) {
       OS::Print("  saved current CTX reg offset %d\n", var_info.index());
     } else {
       if (kind == RawLocalVarDescriptors::kContextLevel) {
         OS::Print("  context level %d scope %d", var_info.index(),
             var_info.scope_id);
       } else if (kind == RawLocalVarDescriptors::kStackVar) {
         OS::Print("  stack var '%s' offset %d",
           var_name.ToCString(), var_info.index());
       } else {
         ASSERT(kind == RawLocalVarDescriptors::kContextVar);
@@ skipping 287 matching lines @@
     const Object& result =
       PassiveObject::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart