Correctly support several consecutive stack modifications.

Review URL: https://chromiumcodereview.appspot.com/10637003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11914 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/debug.cc

@@ -2331,7 +2331,9 @@ bool Debug::IsBreakAtReturn(JavaScriptFrame* frame) {
 void Debug::FramesHaveBeenDropped(StackFrame::Id new_break_frame_id,
                                   FrameDropMode mode,
                                   Object** restarter_frame_function_pointer) {
-  thread_local_.frame_drop_mode_ = mode;
+  if (mode != CURRENTLY_SET_MODE) {
+    thread_local_.frame_drop_mode_ = mode;
+  }
   thread_local_.break_frame_id_ = new_break_frame_id;
   thread_local_.restarter_frame_function_pointer_ =
       restarter_frame_function_pointer;

src/debug.h

@@ -448,7 +448,8 @@ class Debug {
     // The top JS frame had been calling some C++ function. The return address
     // gets patched automatically.
     FRAME_DROPPED_IN_DIRECT_CALL,
-    FRAME_DROPPED_IN_RETURN_CALL
+    FRAME_DROPPED_IN_RETURN_CALL,
+    CURRENTLY_SET_MODE
   };
 
   void FramesHaveBeenDropped(StackFrame::Id new_break_frame_id,

src/liveedit.cc

@@ -1468,7 +1468,9 @@ static const char* DropFrames(Vector<StackFrame*> frames,
       isolate->builtins()->builtin(
           Builtins::kFrameDropper_LiveEdit)) {
     // OK, we can drop our own code.
-    *mode = Debug::FRAME_DROPPED_IN_DIRECT_CALL;
+    pre_top_frame = frames[top_frame_index - 2];
+    top_frame = frames[top_frame_index - 1];
+    *mode = Debug::CURRENTLY_SET_MODE;
     frame_has_padding = false;
   } else if (pre_top_frame_code ==
       isolate->builtins()->builtin(Builtins::kReturn_DebugBreak)) {
@@ -1483,6 +1485,15 @@ static const char* DropFrames(Vector<StackFrame*> frames,
     // Here the stub is CEntry, it's not debug-only and can't be padded.
     // If anyone would complain, a proxy padded stub could be added.
     frame_has_padding = false;
+  } else if (pre_top_frame->type() == StackFrame::ARGUMENTS_ADAPTOR) {
+    // This must be adaptor that remain from the frame dropping that
+    // is still on stack. A frame dropper frame must be above it.
+    ASSERT(frames[top_frame_index - 2]->LookupCode() ==
+        isolate->builtins()->builtin(Builtins::kFrameDropper_LiveEdit));
+    pre_top_frame = frames[top_frame_index - 3];
+    top_frame = frames[top_frame_index - 2];
+    *mode = Debug::CURRENTLY_SET_MODE;
+    frame_has_padding = false;
   } else {
     return "Unknown structure of stack above changing function";
   }

test/mjsunit/debug-liveedit-double-call.js

+// Copyright 2012 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
+// Get the Debug object exposed from the debug context global object.
+
+Debug = debug.Debug
+
+
+function TestCase(test_scenario, expected_output) {
+  // Global variable, accessed from eval'd script.
+  test_output = "";
+
+  var script_text_generator = (function() {
+    var variables = { a: 1, b: 1, c: 1, d: 1, e: 1, f: 1 };
+
+    return {
+      get: function() {
+        return "(function() {\n " +
+            "  function A() {\n " +
+            "    test_output += 'a' + " + variables.a + ";\n " +
+            "    test_output += '=';\n " +
+            "    debugger;\n " +
+            "    return 'Capybara';\n " +
+            "  }\n " +
+            "  function B(p1, p2) {\n " +
+            "    test_output += 'b' + " + variables.b + ";\n " +
+            "    return A();\n " +
+            "  }\n " +
+            "  function C() {\n " +
+            "    test_output += 'c' + " + variables.c + ";\n " +
+            "    // Function call with argument adaptor is intentional.\n " +
+            "    return B();\n " +
+            "  }\n " +
+            "  function D() {\n " +
+            "    test_output += 'd' + " + variables.d + ";\n " +
+            "    // Function call with argument adaptor is intentional.\n " +
+            "    return C(1, 2);\n " +
+            "  }\n " +
+            "  function E() {\n " +
+            "    test_output += 'e' + " + variables.e + ";\n " +
+            "    return D();\n " +
+            "  }\n " +
+            "  function F() {\n " +
+            "    test_output += 'f' + " + variables.f + ";\n " +
+            "    return E();\n " +
+            "  }\n " +
+            "  return F();\n " +
+            "})\n";
+      },
+      change: function(var_name) {
+        variables[var_name]++;
+      }
+    };
+  })();
+
+  var test_fun = eval(script_text_generator.get());
+
+  var script = Debug.findScript(test_fun);
+
+  var scenario_pos = 0;
+
+  function DebuggerStatementHandler() {
+    while (true) {
+      assertTrue(scenario_pos < test_scenario.length);
+      var change_var = test_scenario[scenario_pos++];
+      if (change_var == '=') {
+        // Continue.
+        return;
+      }
+      script_text_generator.change(change_var);
+      try {
+        Debug.LiveEdit.SetScriptSource(script, script_text_generator.get(),
+            false, []);
+      } catch (e) {
+        print("LiveEdit exception: " + e);
+        throw e;
+      }
+    }
+  }
+
+  var saved_exception = null;
+
+  function listener(event, exec_state, event_data, data) {
+    if (event == Debug.DebugEvent.Break) {
+      try {
+        DebuggerStatementHandler();
+      } catch (e) {
+        saved_exception = e;
+      }
+    } else {
+      print("Other: " + event);
+    }
+  }
+
+  Debug.setListener(listener);
+  assertEquals("Capybara", test_fun());
+  Debug.setListener(null);
+
+  if (saved_exception) {
+    print("Exception: " + saved_exception);
+    assertUnreachable();
+  }
+
+  print(test_output);
+
+  assertEquals(expected_output, test_output);
+}
+
+TestCase(['='], "f1e1d1c1b1a1=");
+
+TestCase(['c', '=', '='], "f1e1d1c1b1a1=c2b1a1=");
+
+TestCase(['b', 'c', 'd', 'e', '=', '='], "f1e1d1c1b1a1=e2d2c2b2a1=");
+
+TestCase(['b', 'c', '=', 'b', 'c', 'd', 'e', '=', '='], "f1e1d1c1b1a1=c2b2a1=e2d2c3b3a1=");
+
+TestCase(['e', 'f', '=', '='], "f1e1d1c1b1a1=f2e2d1c1b1a1=");