Correctly resolve forcibly context allocated parameters in debug-evaluate.

R=ulan@chromium.org
BUG=325676
LOG=Y

Review URL: https://codereview.chromium.org/107243006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18402 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/runtime.cc

@@ -11373,6 +11373,12 @@ static Handle<JSObject> MaterializeStackLocalsWithFrameInspector(
 
   // First fill all parameters.
   for (int i = 0; i < scope_info->ParameterCount(); ++i) {
+    Handle<String> name(scope_info->ParameterName(i));
+    VariableMode mode;
+    InitializationFlag init_flag;
+    // Do not materialize the parameter if it is shadowed by a context local.
+    if (scope_info->ContextSlotIndex(*name, &mode, &init_flag) != -1) continue;
+
     Handle<Object> value(i < frame_inspector->GetParametersCount()
                              ? frame_inspector->GetParameter(i)
                              : isolate->heap()->undefined_value(),
@@ -11381,29 +11387,21 @@ static Handle<JSObject> MaterializeStackLocalsWithFrameInspector(
 
     RETURN_IF_EMPTY_HANDLE_VALUE(
         isolate,
-        Runtime::SetObjectProperty(isolate,
-                                   target,
-                                   Handle<String>(scope_info->ParameterName(i)),
-                                   value,
-                                   NONE,
-                                   kNonStrictMode),
+        Runtime::SetObjectProperty(
+            isolate, target, name, value, NONE, kNonStrictMode),
         Handle<JSObject>());
   }
 
   // Second fill all stack locals.
   for (int i = 0; i < scope_info->StackLocalCount(); ++i) {
+    Handle<String> name(scope_info->StackLocalName(i));
     Handle<Object> value(frame_inspector->GetExpression(i), isolate);
     if (value->IsTheHole()) continue;
 
     RETURN_IF_EMPTY_HANDLE_VALUE(
         isolate,
         Runtime::SetObjectProperty(
-            isolate,
-            target,
-            Handle<String>(scope_info->StackLocalName(i)),
-            value,
-            NONE,
-            kNonStrictMode),
+            isolate, target, name, value, NONE, kNonStrictMode),
         Handle<JSObject>());
   }
 

test/mjsunit/regress/regress-325676.js

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --expose-debug-as debug
+
+// If a function parameter is forced to be context allocated,
+// debug evaluate need to resolve it to a context slot instead of
+// parameter slot on the stack.
+
+var Debug = debug.Debug;
+
+var expected;
+var exception = null;
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Break) return;
+  try {
+    assertEquals(expected, exec_state.frame(0).evaluate('arg').value());
+    exec_state.frame(0).evaluate('arg = "evaluated";');
+  } catch (e) {
+    exception = e;
+  }
+}
+
+Debug.setListener(listener);
+
+function f(arg) {
+  expected = arg;
+  debugger;
+  assertEquals("evaluated", arg);
+
+  arg = "value";
+  expected = arg;
+  debugger;
+  assertEquals("evaluated", arg);
+
+  // Forces arg to be context allocated even though a parameter.
+  function g() { arg; }
+}
+
+f();
+f(1);
+f(1, 2);
+
+assertNull(exception);