Update V8 to version 4.1.0.21

This is a cherry-pick of all commits up to and including the
4.1.0.21 cherry-pick in Chromium.

Original commit message:

Version 4.1.0.21 (cherry-pick)

Merged 206e9136bde0f2b5ae8cb77afbb1e7833e5bd412

Unlink pages from the space page list after evacuation.

BUG=430201
LOG=N
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/953813002

Cr-Commit-Position: refs/branch-heads/4.1@{#22}
Cr-Branched-From: 2e08d2a7aa9d65d269d8c57aba82eb38a8cb0a18-refs/heads/candidates@{#25353}

---

FPIIM-449

Change-Id: I8c23c7bbb70772b4858fe8a47b64fa97ee0d1f8c
diff --git a/src/runtime/runtime-liveedit.cc b/src/runtime/runtime-liveedit.cc
new file mode 100644
index 0000000..b453d15
--- /dev/null
+++ b/src/runtime/runtime-liveedit.cc
@@ -0,0 +1,293 @@
+// Copyright 2014 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/v8.h"
+
+#include "src/arguments.h"
+#include "src/debug.h"
+#include "src/liveedit.h"
+#include "src/runtime/runtime.h"
+#include "src/runtime/runtime-utils.h"
+
+namespace v8 {
+namespace internal {
+
+
+static int FindSharedFunctionInfosForScript(HeapIterator* iterator,
+                                            Script* script,
+                                            FixedArray* buffer) {
+  DisallowHeapAllocation no_allocation;
+  int counter = 0;
+  int buffer_size = buffer->length();
+  for (HeapObject* obj = iterator->next(); obj != NULL;
+       obj = iterator->next()) {
+    DCHECK(obj != NULL);
+    if (!obj->IsSharedFunctionInfo()) {
+      continue;
+    }
+    SharedFunctionInfo* shared = SharedFunctionInfo::cast(obj);
+    if (shared->script() != script) {
+      continue;
+    }
+    if (counter < buffer_size) {
+      buffer->set(counter, shared);
+    }
+    counter++;
+  }
+  return counter;
+}
+
+
+// For a script finds all SharedFunctionInfo's in the heap that points
+// to this script. Returns JSArray of SharedFunctionInfo wrapped
+// in OpaqueReferences.
+RUNTIME_FUNCTION(Runtime_LiveEditFindSharedFunctionInfosForScript) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_CHECKED(JSValue, script_value, 0);
+
+  RUNTIME_ASSERT(script_value->value()->IsScript());
+  Handle<Script> script = Handle<Script>(Script::cast(script_value->value()));
+
+  const int kBufferSize = 32;
+
+  Handle<FixedArray> array;
+  array = isolate->factory()->NewFixedArray(kBufferSize);
+  int number;
+  Heap* heap = isolate->heap();
+  {
+    HeapIterator heap_iterator(heap);
+    Script* scr = *script;
+    FixedArray* arr = *array;
+    number = FindSharedFunctionInfosForScript(&heap_iterator, scr, arr);
+  }
+  if (number > kBufferSize) {
+    array = isolate->factory()->NewFixedArray(number);
+    HeapIterator heap_iterator(heap);
+    Script* scr = *script;
+    FixedArray* arr = *array;
+    FindSharedFunctionInfosForScript(&heap_iterator, scr, arr);
+  }
+
+  Handle<JSArray> result = isolate->factory()->NewJSArrayWithElements(array);
+  result->set_length(Smi::FromInt(number));
+
+  LiveEdit::WrapSharedFunctionInfos(result);
+
+  return *result;
+}
+
+
+// For a script calculates compilation information about all its functions.
+// The script source is explicitly specified by the second argument.
+// The source of the actual script is not used, however it is important that
+// all generated code keeps references to this particular instance of script.
+// Returns a JSArray of compilation infos. The array is ordered so that
+// each function with all its descendant is always stored in a continues range
+// with the function itself going first. The root function is a script function.
+RUNTIME_FUNCTION(Runtime_LiveEditGatherCompileInfo) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_CHECKED(JSValue, script, 0);
+  CONVERT_ARG_HANDLE_CHECKED(String, source, 1);
+
+  RUNTIME_ASSERT(script->value()->IsScript());
+  Handle<Script> script_handle = Handle<Script>(Script::cast(script->value()));
+
+  Handle<JSArray> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result, LiveEdit::GatherCompileInfo(script_handle, source));
+  return *result;
+}
+
+
+// Changes the source of the script to a new_source.
+// If old_script_name is provided (i.e. is a String), also creates a copy of
+// the script with its original source and sends notification to debugger.
+RUNTIME_FUNCTION(Runtime_LiveEditReplaceScript) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 3);
+  CONVERT_ARG_CHECKED(JSValue, original_script_value, 0);
+  CONVERT_ARG_HANDLE_CHECKED(String, new_source, 1);
+  CONVERT_ARG_HANDLE_CHECKED(Object, old_script_name, 2);
+
+  RUNTIME_ASSERT(original_script_value->value()->IsScript());
+  Handle<Script> original_script(Script::cast(original_script_value->value()));
+
+  Handle<Object> old_script = LiveEdit::ChangeScriptSource(
+      original_script, new_source, old_script_name);
+
+  if (old_script->IsScript()) {
+    Handle<Script> script_handle = Handle<Script>::cast(old_script);
+    return *Script::GetWrapper(script_handle);
+  } else {
+    return isolate->heap()->null_value();
+  }
+}
+
+
+RUNTIME_FUNCTION(Runtime_LiveEditFunctionSourceUpdated) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_info, 0);
+  RUNTIME_ASSERT(SharedInfoWrapper::IsInstance(shared_info));
+
+  LiveEdit::FunctionSourceUpdated(shared_info);
+  return isolate->heap()->undefined_value();
+}
+
+
+// Replaces code of SharedFunctionInfo with a new one.
+RUNTIME_FUNCTION(Runtime_LiveEditReplaceFunctionCode) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, new_compile_info, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_info, 1);
+  RUNTIME_ASSERT(SharedInfoWrapper::IsInstance(shared_info));
+
+  LiveEdit::ReplaceFunctionCode(new_compile_info, shared_info);
+  return isolate->heap()->undefined_value();
+}
+
+
+// Connects SharedFunctionInfo to another script.
+RUNTIME_FUNCTION(Runtime_LiveEditFunctionSetScript) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(Object, function_object, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, script_object, 1);
+
+  if (function_object->IsJSValue()) {
+    Handle<JSValue> function_wrapper = Handle<JSValue>::cast(function_object);
+    if (script_object->IsJSValue()) {
+      RUNTIME_ASSERT(JSValue::cast(*script_object)->value()->IsScript());
+      Script* script = Script::cast(JSValue::cast(*script_object)->value());
+      script_object = Handle<Object>(script, isolate);
+    }
+    RUNTIME_ASSERT(function_wrapper->value()->IsSharedFunctionInfo());
+    LiveEdit::SetFunctionScript(function_wrapper, script_object);
+  } else {
+    // Just ignore this. We may not have a SharedFunctionInfo for some functions
+    // and we check it in this function.
+  }
+
+  return isolate->heap()->undefined_value();
+}
+
+
+// In a code of a parent function replaces original function as embedded object
+// with a substitution one.
+RUNTIME_FUNCTION(Runtime_LiveEditReplaceRefToNestedFunction) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 3);
+
+  CONVERT_ARG_HANDLE_CHECKED(JSValue, parent_wrapper, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSValue, orig_wrapper, 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSValue, subst_wrapper, 2);
+  RUNTIME_ASSERT(parent_wrapper->value()->IsSharedFunctionInfo());
+  RUNTIME_ASSERT(orig_wrapper->value()->IsSharedFunctionInfo());
+  RUNTIME_ASSERT(subst_wrapper->value()->IsSharedFunctionInfo());
+
+  LiveEdit::ReplaceRefToNestedFunction(parent_wrapper, orig_wrapper,
+                                       subst_wrapper);
+  return isolate->heap()->undefined_value();
+}
+
+
+// Updates positions of a shared function info (first parameter) according
+// to script source change. Text change is described in second parameter as
+// array of groups of 3 numbers:
+// (change_begin, change_end, change_end_new_position).
+// Each group describes a change in text; groups are sorted by change_begin.
+RUNTIME_FUNCTION(Runtime_LiveEditPatchFunctionPositions) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_array, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, position_change_array, 1);
+  RUNTIME_ASSERT(SharedInfoWrapper::IsInstance(shared_array))
+
+  LiveEdit::PatchFunctionPositions(shared_array, position_change_array);
+  return isolate->heap()->undefined_value();
+}
+
+
+// For array of SharedFunctionInfo's (each wrapped in JSValue)
+// checks that none of them have activations on stacks (of any thread).
+// Returns array of the same length with corresponding results of
+// LiveEdit::FunctionPatchabilityStatus type.
+RUNTIME_FUNCTION(Runtime_LiveEditCheckAndDropActivations) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_array, 0);
+  CONVERT_BOOLEAN_ARG_CHECKED(do_drop, 1);
+  RUNTIME_ASSERT(shared_array->length()->IsSmi());
+  RUNTIME_ASSERT(shared_array->HasFastElements())
+  int array_length = Smi::cast(shared_array->length())->value();
+  for (int i = 0; i < array_length; i++) {
+    Handle<Object> element =
+        Object::GetElement(isolate, shared_array, i).ToHandleChecked();
+    RUNTIME_ASSERT(
+        element->IsJSValue() &&
+        Handle<JSValue>::cast(element)->value()->IsSharedFunctionInfo());
+  }
+
+  return *LiveEdit::CheckAndDropActivations(shared_array, do_drop);
+}
+
+
+// Compares 2 strings line-by-line, then token-wise and returns diff in form
+// of JSArray of triplets (pos1, pos1_end, pos2_end) describing list
+// of diff chunks.
+RUNTIME_FUNCTION(Runtime_LiveEditCompareStrings) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(String, s1, 0);
+  CONVERT_ARG_HANDLE_CHECKED(String, s2, 1);
+
+  return *LiveEdit::CompareStrings(s1, s2);
+}
+
+
+// Restarts a call frame and completely drops all frames above.
+// Returns true if successful. Otherwise returns undefined or an error message.
+RUNTIME_FUNCTION(Runtime_LiveEditRestartFrame) {
+  HandleScope scope(isolate);
+  CHECK(isolate->debug()->live_edit_enabled());
+  DCHECK(args.length() == 2);
+  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
+  RUNTIME_ASSERT(isolate->debug()->CheckExecutionState(break_id));
+
+  CONVERT_NUMBER_CHECKED(int, index, Int32, args[1]);
+  Heap* heap = isolate->heap();
+
+  // Find the relevant frame with the requested index.
+  StackFrame::Id id = isolate->debug()->break_frame_id();
+  if (id == StackFrame::NO_ID) {
+    // If there are no JavaScript stack frames return undefined.
+    return heap->undefined_value();
+  }
+
+  JavaScriptFrameIterator it(isolate, id);
+  int inlined_jsframe_index = Runtime::FindIndexedNonNativeFrame(&it, index);
+  if (inlined_jsframe_index == -1) return heap->undefined_value();
+  // We don't really care what the inlined frame index is, since we are
+  // throwing away the entire frame anyways.
+  const char* error_message = LiveEdit::RestartFrame(it.frame());
+  if (error_message) {
+    return *(isolate->factory()->InternalizeUtf8String(error_message));
+  }
+  return heap->true_value();
+}
+}
+}  // namespace v8::internal