[debugger] do not predict step in target for liveedit.

src/debug/debug.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/debug/debug.h"
 
 #include "src/api.h"
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 318 matching lines @@
   thread_local_.last_step_action_ = StepNone;
   thread_local_.last_statement_position_ = RelocInfo::kNoPosition;
   thread_local_.step_count_ = 0;
   thread_local_.last_fp_ = 0;
   thread_local_.queued_step_count_ = 0;
   thread_local_.step_out_fp_ = 0;
   thread_local_.step_in_enabled_ = false;
   // TODO(isolates): frames_are_dropped_?
   base::NoBarrier_Store(&thread_local_.current_debug_scope_,
                         static_cast<base::AtomicWord>(0));
-  thread_local_.restarter_frame_function_pointer_ = NULL;
 }
 
 
 char* Debug::ArchiveDebug(char* storage) {
   char* to = storage;
   MemCopy(to, reinterpret_cast<char*>(&thread_local_), sizeof(ThreadLocal));
   ThreadInit();
   return storage + ArchiveSpacePerThread();
 }
 
@@ skipping 471 matching lines @@
 }
 
 
 void Debug::PrepareStep(StepAction step_action,
                         int step_count,
                         StackFrame::Id frame_id) {
   HandleScope scope(isolate_);
 
   DCHECK(in_debug_scope());
 
-  // Remember this step action and count.
-  thread_local_.last_step_action_ = step_action;
-  STATIC_ASSERT(StepFrame > StepIn);
-  thread_local_.step_in_enabled_ = (step_action >= StepIn);
-  if (step_action == StepOut) {
-    // For step out target frame will be found on the stack so there is no need
-    // to set step counter for it. It's expected to always be 0 for StepOut.
-    thread_local_.step_count_ = 0;
-  } else {
-    thread_local_.step_count_ = step_count;
-  }
-
   // Get the frame where the execution has stopped and skip the debug frame if
   // any. The debug frame will only be present if execution was stopped due to
   // hitting a break point. In other situations (e.g. unhandled exception) the
   // debug frame is not present.
   StackFrame::Id id = break_frame_id();
   if (id == StackFrame::NO_ID) {
     // If there is no JavaScript stack don't do anything.
     return;
   }
   if (frame_id != StackFrame::NO_ID) {
     id = frame_id;
   }
   JavaScriptFrameIterator frames_it(isolate_, id);
   JavaScriptFrame* frame = frames_it.frame();
 
   feature_tracker()->Track(DebugFeatureTracker::kStepping);
 
+  // Remember this step action and count.
+  thread_local_.last_step_action_ = step_action;
+  STATIC_ASSERT(StepFrame > StepIn);
+  thread_local_.step_in_enabled_ = (step_action >= StepIn);
+  if (step_action == StepOut) {
+    // For step out target frame will be found on the stack so there is no need
+    // to set step counter for it. It's expected to always be 0 for StepOut.
+    thread_local_.step_count_ = 0;
+  } else {
+    thread_local_.step_count_ = step_count;
+  }
+
   // First of all ensure there is one-shot break points in the top handler
   // if any.
   FloodHandlerWithOneShot();
 
   // If the function on the top frame is unresolved perform step out. This will
   // be the case when calling unknown function and having the debugger stopped
   // in an unhandled exception.
   if (!frame->function()->IsJSFunction()) {
     // Step out: Find the calling JavaScript frame and flood it with
     // breakpoints.
@@ skipping 54 matching lines @@
       // Set target frame pointer.
       ActivateStepOut(frames_it.frame());
     } else {
       // Stepping out to the embedder. Disable step-in to avoid stepping into
       // the next (unrelated) call that the embedder makes.
       thread_local_.step_in_enabled_ = false;
     }
     return;
   }
 
-  STATIC_ASSERT(StepFrame > StepIn);
-  if (step_action >= StepIn) {
-    // If there's restarter frame on top of the stack, just get the pointer
-    // to function which is going to be restarted.
-    if (thread_local_.restarter_frame_function_pointer_ != NULL) {
-      Handle<JSFunction> restarted_function(
-          JSFunction::cast(*thread_local_.restarter_frame_function_pointer_));
-      FloodWithOneShot(restarted_function);
-    }
-  }
-
   // Fill the current function with one-shot break points even for step in on
   // a call target as the function called might be a native function for
   // which step in will not stop. It also prepares for stepping in
   // getters/setters.
   // If we are stepping into another frame, only fill calls and returns.
   FloodWithOneShot(function, step_action == StepFrame ? CALLS_AND_RETURNS
                                                       : ALL_BREAK_LOCATIONS);
 
   // Remember source position and frame to handle step next.
   thread_local_.last_statement_position_ =
@@ skipping 87 matching lines @@
 }
 
 
 void Debug::ClearStepping() {
   // Clear the various stepping setup.
   ClearOneShot();
   ClearStepOut();
 
   thread_local_.step_count_ = 0;
   thread_local_.last_step_action_ = StepNone;
+  thread_local_.step_in_enabled_ = false;
   thread_local_.last_statement_position_ = RelocInfo::kNoPosition;
   thread_local_.last_fp_ = 0;
 }
 
 
 // Clears all the one-shot break points that are currently set. Normally this
 // function is called each time a break point is hit as one shot break points
 // are used to support stepping.
 void Debug::ClearOneShot() {
   // The current implementation just runs through all the breakpoints. When the
@@ skipping 453 matching lines @@
   Address slot_pc = frame->pc() - Assembler::kDebugBreakSlotLength;
   int mask = RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_RETURN);
   for (RelocIterator it(*code, mask); !it.done(); it.next()) {
     if (it.rinfo()->pc() == slot_pc) return true;
   }
   return false;
 }
 
 
 void Debug::FramesHaveBeenDropped(StackFrame::Id new_break_frame_id,
-                                  LiveEdit::FrameDropMode mode,
-                                  Object** restarter_frame_function_pointer) {
+                                  LiveEdit::FrameDropMode mode) {
   if (mode != LiveEdit::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;
 }
 
 
 bool Debug::IsDebugGlobal(JSGlobalObject* global) {
   return is_loaded() && global == debug_context()->global_object();
 }
 
 
 void Debug::ClearMirrorCache() {
   PostponeInterruptsScope postpone(isolate_);
@@ skipping 977 matching lines @@
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 }  // namespace internal
 }  // namespace v8