1// Copyright 2010 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28#ifndef V8_VM_STATE_INL_H_
29#define V8_VM_STATE_INL_H_
30
31#include "vm-state.h"
32#include "runtime-profiler.h"
33
34namespace v8 {
35namespace internal {
36
37//
38// VMState class implementation.  A simple stack of VM states held by the
39// logger and partially threaded through the call stack.  States are pushed by
40// VMState construction and popped by destruction.
41//
42#ifdef ENABLE_VMSTATE_TRACKING
43inline const char* StateToString(StateTag state) {
44  switch (state) {
45    case JS:
46      return "JS";
47    case GC:
48      return "GC";
49    case COMPILER:
50      return "COMPILER";
51    case OTHER:
52      return "OTHER";
53    case EXTERNAL:
54      return "EXTERNAL";
55    default:
56      UNREACHABLE();
57      return NULL;
58  }
59}
60
61
62VMState::VMState(Isolate* isolate, StateTag tag)
63    : isolate_(isolate), previous_tag_(isolate->current_vm_state()) {
64#ifdef ENABLE_LOGGING_AND_PROFILING
65  if (FLAG_log_state_changes) {
66    LOG(isolate, UncheckedStringEvent("Entering", StateToString(tag)));
67    LOG(isolate, UncheckedStringEvent("From", StateToString(previous_tag_)));
68  }
69#endif
70
71  isolate_->SetCurrentVMState(tag);
72
73#ifdef ENABLE_HEAP_PROTECTION
74  if (FLAG_protect_heap) {
75    if (tag == EXTERNAL) {
76      // We are leaving V8.
77      ASSERT(previous_tag_ != EXTERNAL);
78      isolate_->heap()->Protect();
79    } else if (previous_tag_ = EXTERNAL) {
80      // We are entering V8.
81      isolate_->heap()->Unprotect();
82    }
83  }
84#endif
85}
86
87
88VMState::~VMState() {
89#ifdef ENABLE_LOGGING_AND_PROFILING
90  if (FLAG_log_state_changes) {
91    LOG(isolate_,
92        UncheckedStringEvent("Leaving",
93                              StateToString(isolate_->current_vm_state())));
94    LOG(isolate_,
95        UncheckedStringEvent("To", StateToString(previous_tag_)));
96  }
97#endif  // ENABLE_LOGGING_AND_PROFILING
98
99#ifdef ENABLE_HEAP_PROTECTION
100  StateTag tag = isolate_->current_vm_state();
101#endif
102
103  isolate_->SetCurrentVMState(previous_tag_);
104
105#ifdef ENABLE_HEAP_PROTECTION
106  if (FLAG_protect_heap) {
107    if (tag == EXTERNAL) {
108      // We are reentering V8.
109      ASSERT(previous_tag_ != EXTERNAL);
110      isolate_->heap()->Unprotect();
111    } else if (previous_tag_ == EXTERNAL) {
112      // We are leaving V8.
113      isolate_->heap()->Protect();
114    }
115  }
116#endif  // ENABLE_HEAP_PROTECTION
117}
118
119#endif  // ENABLE_VMSTATE_TRACKING
120
121
122#ifdef ENABLE_LOGGING_AND_PROFILING
123
124ExternalCallbackScope::ExternalCallbackScope(Isolate* isolate, Address callback)
125    : isolate_(isolate), previous_callback_(isolate->external_callback()) {
126  isolate_->set_external_callback(callback);
127}
128
129ExternalCallbackScope::~ExternalCallbackScope() {
130  isolate_->set_external_callback(previous_callback_);
131}
132
133#endif  // ENABLE_LOGGING_AND_PROFILING
134
135
136} }  // namespace v8::internal
137
138#endif  // V8_VM_STATE_INL_H_
139