When a value has been optimized away by the compiler, set its value to

runtime/vm/debugger_api_impl_test.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 "include/dart_debugger_api.h"
 #include "include/dart_mirrors_api.h"
 #include "platform/assert.h"
 #include "vm/dart_api_impl.h"
 #include "vm/thread.h"
 #include "vm/unit_test.h"
@@ skipping 435 matching lines @@
   // Set up the breakpoint.
   Dart_SetPausedEventHandler(InspectOptimizedStack_Breakpoint);
   SetBreakpointAtEntry("", "breakpointNow");
 
   // Run the code and inspect the stack.
   stack_buffer[0] = '\0';
   dart_args[0] = Dart_True();
   dart_args[1] = Dart_NewInteger(kLowThreshold);
   EXPECT_VALID(Dart_Invoke(script_lib, NewString("test"), 2, dart_args));
   if (optimize) {
-    // Note that several variables have the value 'null' in the
-    // optimized case.  This is because these values were determined
-    // to be dead by the optimizing compiler and their values were not
-    // preserved by the deopt information.
     EXPECT_STREQ("[0] breakpointNow { }\n"
-                 "[1] helper { a = 5 b = 99 stop = null }\n"
-                 "[2] anotherMiddleMan { one = null two = null stop = null }\n"
+                 "[1] helper { a = 5 b = 99 stop = <optimized out> }\n"
+                 "[2] anotherMiddleMan { one = <optimized out> "
+                 "two = <optimized out> stop = <optimized out> }\n"
                  "[3] middleMan { x = 5 limit = 100 stop = true value = 24255"
                  " i = 99 }\n"
                  "[4] test { stop = true limit = 100 }\n",
                  stack_buffer);
   } else {
     EXPECT_STREQ("[0] breakpointNow { }\n"
                  "[1] helper { a = 5 b = 99 stop = true }\n"
                  "[2] anotherMiddleMan { one = 5 two = 99 stop = true }\n"
                  "[3] middleMan { x = 5 limit = 100 stop = true value = 24255"
                  " i = 99 }\n"
@@ skipping 69 matching lines @@
   Dart_SetPausedEventHandler(InspectOptimizedStack_Breakpoint);
   SetBreakpointAtEntry("", "breakpointNow");
 
   // Run the code and inspect the stack.
   stack_buffer[0] = '\0';
   dart_args[0] = Dart_True();
   dart_args[1] = Dart_NewInteger(kLowThreshold);
   EXPECT_VALID(Dart_Invoke(script_lib, NewString("test"), 2, dart_args));
   if (optimize) {
     EXPECT_STREQ("[0] breakpointNow { }\n"
-                 "[1] helper { a = 50 b = 99 stop = null }\n"
+                 "[1] helper { a = 50 b = 99 stop = <optimized out> }\n"
                  "[2] <anonymous closure> { x = 5 i = 99 stop = true"
-                 " value = null }\n"
-                 "[3] anotherMiddleMan { func = null }\n"
+                 " value = <optimized out> }\n"
+                 "[3] anotherMiddleMan { func = <optimized out> }\n"
                  "[4] middleMan { x = 5 limit = 100 stop = true"
                  " value = 242550 i = 99 }\n"
                  "[5] test { stop = true limit = 100 }\n",
                  stack_buffer);
   } else {
     EXPECT_STREQ("[0] breakpointNow { }\n"
                  "[1] helper { a = 50 b = 99 stop = true }\n"
                  "[2] <anonymous closure> { x = 5 i = 99 stop = true"
                  " value = 10 }\n"
                  "[3] anotherMiddleMan {"
@@ skipping 1451 matching lines @@
 
   Dart_Handle list_type = Dart_InstanceGetType(list_access_test_obj);
   Dart_Handle super_type = Dart_GetSupertype(list_type);
   EXPECT(!Dart_IsError(super_type));
   super_type = Dart_GetSupertype(super_type);
   EXPECT(!Dart_IsError(super_type));
   EXPECT(super_type == Dart_Null());
 }
 
 }  // namespace dart