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+// Copyright 2006-2008 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.
+
+#ifndef V8_LOG_H_
+#define V8_LOG_H_
+
+#include "platform.h"
+#include "log-utils.h"
+
+namespace v8 {
+namespace internal {
+
+// Logger is used for collecting logging information from V8 during
+// execution. The result is dumped to a file.
+//
+// Available command line flags:
+//
+//  --log
+// Minimal logging (no API, code, or GC sample events), default is off.
+//
+// --log-all
+// Log all events to the file, default is off.  This is the same as combining
+// --log-api, --log-code, --log-gc, and --log-regexp.
+//
+// --log-api
+// Log API events to the logfile, default is off.  --log-api implies --log.
+//
+// --log-code
+// Log code (create, move, and delete) events to the logfile, default is off.
+// --log-code implies --log.
+//
+// --log-gc
+// Log GC heap samples after each GC that can be processed by hp2ps, default
+// is off.  --log-gc implies --log.
+//
+// --log-regexp
+// Log creation and use of regular expressions, Default is off.
+// --log-regexp implies --log.
+//
+// --logfile <filename>
+// Specify the name of the logfile, default is "v8.log".
+//
+// --prof
+// Collect statistical profiling information (ticks), default is off.  The
+// tick profiler requires code events, so --prof implies --log-code.
+
+// Forward declarations.
+class Ticker;
+class Profiler;
+class Semaphore;
+class SlidingStateWindow;
+class LogMessageBuilder;
+class CompressionHelper;
+
+#undef LOG
+#ifdef ENABLE_LOGGING_AND_PROFILING
+#define LOG(Call)                           \
+  do {                                      \
+    if (v8::internal::Logger::is_logging()) \
+      v8::internal::Logger::Call;           \
+  } while (false)
+#else
+#define LOG(Call) ((void) 0)
+#endif
+
+
+class VMState BASE_EMBEDDED {
+#ifdef ENABLE_LOGGING_AND_PROFILING
+ public:
+  inline explicit VMState(StateTag state);
+  inline ~VMState();
+
+  StateTag state() { return state_; }
+
+ private:
+  bool disabled_;
+  StateTag state_;
+  VMState* previous_;
+#else
+ public:
+  explicit VMState(StateTag state) {}
+#endif
+};
+
+
+#define LOG_EVENTS_AND_TAGS_LIST(V) \
+  V(CODE_CREATION_EVENT,            "code-creation",          "cc")       \
+  V(CODE_MOVE_EVENT,                "code-move",              "cm")       \
+  V(CODE_DELETE_EVENT,              "code-delete",            "cd")       \
+  V(TICK_EVENT,                     "tick",                   "t")        \
+  V(REPEAT_META_EVENT,              "repeat",                 "r")        \
+  V(BUILTIN_TAG,                    "Builtin",                "bi")       \
+  V(CALL_DEBUG_BREAK_TAG,           "CallDebugBreak",         "cdb")      \
+  V(CALL_DEBUG_PREPARE_STEP_IN_TAG, "CallDebugPrepareStepIn", "cdbsi")    \
+  V(CALL_IC_TAG,                    "CallIC",                 "cic")      \
+  V(CALL_INITIALIZE_TAG,            "CallInitialize",         "ci")       \
+  V(CALL_MEGAMORPHIC_TAG,           "CallMegamorphic",        "cmm")      \
+  V(CALL_MISS_TAG,                  "CallMiss",               "cm")       \
+  V(CALL_NORMAL_TAG,                "CallNormal",             "cn")       \
+  V(CALL_PRE_MONOMORPHIC_TAG,       "CallPreMonomorphic",     "cpm")      \
+  V(EVAL_TAG,                       "Eval",                   "e")        \
+  V(FUNCTION_TAG,                   "Function",               "f")        \
+  V(KEYED_LOAD_IC_TAG,              "KeyedLoadIC",            "klic")     \
+  V(KEYED_STORE_IC_TAG,             "KeyedStoreIC",           "ksic")     \
+  V(LAZY_COMPILE_TAG,               "LazyCompile",            "lc")       \
+  V(LOAD_IC_TAG,                    "LoadIC",                 "lic")      \
+  V(REG_EXP_TAG,                    "RegExp",                 "re")       \
+  V(SCRIPT_TAG,                     "Script",                 "sc")       \
+  V(STORE_IC_TAG,                   "StoreIC",                "sic")      \
+  V(STUB_TAG,                       "Stub",                   "s")
+
+class Logger {
+ public:
+#define DECLARE_ENUM(enum_item, ignore1, ignore2) enum_item,
+  enum LogEventsAndTags {
+    LOG_EVENTS_AND_TAGS_LIST(DECLARE_ENUM)
+    NUMBER_OF_LOG_EVENTS
+  };
+#undef DECLARE_ENUM
+
+  // Acquires resources for logging if the right flags are set.
+  static bool Setup();
+
+  // Frees resources acquired in Setup.
+  static void TearDown();
+
+  // Enable the computation of a sliding window of states.
+  static void EnableSlidingStateWindow();
+
+  // Write a raw string to the log to be used as a preamble.
+  // No check is made that the 'preamble' is actually at the beginning
+  // of the log. The preample is used to write code events saved in the
+  // snapshot.
+  static void Preamble(const char* content);
+
+  // Emits an event with a string value -> (name, value).
+  static void StringEvent(const char* name, const char* value);
+
+  // Emits an event with an int value -> (name, value).
+  static void IntEvent(const char* name, int value);
+
+  // Emits an event with an handle value -> (name, location).
+  static void HandleEvent(const char* name, Object** location);
+
+  // Emits memory management events for C allocated structures.
+  static void NewEvent(const char* name, void* object, size_t size);
+  static void DeleteEvent(const char* name, void* object);
+
+  // Emits an event with a tag, and some resource usage information.
+  // -> (name, tag, <rusage information>).
+  // Currently, the resource usage information is a process time stamp
+  // and a real time timestamp.
+  static void ResourceEvent(const char* name, const char* tag);
+
+  // Emits an event that an undefined property was read from an
+  // object.
+  static void SuspectReadEvent(String* name, Object* obj);
+
+  // Emits an event when a message is put on or read from a debugging queue.
+  // DebugTag lets us put a call-site specific label on the event.
+  static void DebugTag(const char* call_site_tag);
+  static void DebugEvent(const char* event_type, Vector<uint16_t> parameter);
+
+
+  // ==== Events logged by --log-api. ====
+  static void ApiNamedSecurityCheck(Object* key);
+  static void ApiIndexedSecurityCheck(uint32_t index);
+  static void ApiNamedPropertyAccess(const char* tag,
+                                     JSObject* holder,
+                                     Object* name);
+  static void ApiIndexedPropertyAccess(const char* tag,
+                                       JSObject* holder,
+                                       uint32_t index);
+  static void ApiObjectAccess(const char* tag, JSObject* obj);
+  static void ApiEntryCall(const char* name);
+
+
+  // ==== Events logged by --log-code. ====
+  // Emits a code create event.
+  static void CodeCreateEvent(LogEventsAndTags tag,
+                              Code* code, const char* source);
+  static void CodeCreateEvent(LogEventsAndTags tag, Code* code, String* name);
+  static void CodeCreateEvent(LogEventsAndTags tag, Code* code, String* name,
+                              String* source, int line);
+  static void CodeCreateEvent(LogEventsAndTags tag, Code* code, int args_count);
+  // Emits a code create event for a RegExp.
+  static void RegExpCodeCreateEvent(Code* code, String* source);
+  // Emits a code move event.
+  static void CodeMoveEvent(Address from, Address to);
+  // Emits a code delete event.
+  static void CodeDeleteEvent(Address from);
+
+  // ==== Events logged by --log-gc. ====
+  // Heap sampling events: start, end, and individual types.
+  static void HeapSampleBeginEvent(const char* space, const char* kind);
+  static void HeapSampleEndEvent(const char* space, const char* kind);
+  static void HeapSampleItemEvent(const char* type, int number, int bytes);
+  static void HeapSampleJSConstructorEvent(const char* constructor,
+                                           int number, int bytes);
+  static void HeapSampleJSRetainersEvent(const char* constructor,
+                                         const char* event);
+  static void HeapSampleStats(const char* space, const char* kind,
+                              int capacity, int used);
+
+  static void SharedLibraryEvent(const char* library_path,
+                                 uintptr_t start,
+                                 uintptr_t end);
+  static void SharedLibraryEvent(const wchar_t* library_path,
+                                 uintptr_t start,
+                                 uintptr_t end);
+
+  // ==== Events logged by --log-regexp ====
+  // Regexp compilation and execution events.
+
+  static void RegExpCompileEvent(Handle<JSRegExp> regexp, bool in_cache);
+
+  // Log an event reported from generated code
+  static void LogRuntime(Vector<const char> format, JSArray* args);
+
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  static StateTag state() {
+    return current_state_ ? current_state_->state() : OTHER;
+  }
+
+  static bool is_logging() {
+    return is_logging_;
+  }
+
+  // Pause/Resume collection of profiling data.
+  // When data collection is paused, CPU Tick events are discarded until
+  // data collection is Resumed.
+  static void PauseProfiler(int flags);
+  static void ResumeProfiler(int flags);
+  static int GetActiveProfilerModules();
+
+  // If logging is performed into a memory buffer, allows to
+  // retrieve previously written messages. See v8.h.
+  static int GetLogLines(int from_pos, char* dest_buf, int max_size);
+
+  // Logs all compiled functions found in the heap.
+  static void LogCompiledFunctions();
+
+ private:
+
+  // Profiler's sampling interval (in milliseconds).
+  static const int kSamplingIntervalMs = 1;
+
+  // Size of window used for log records compression.
+  static const int kCompressionWindowSize = 4;
+
+  // Emits the profiler's first message.
+  static void ProfilerBeginEvent();
+
+  // Emits aliases for compressed messages.
+  static void LogAliases();
+
+  // Emits the source code of a regexp. Used by regexp events.
+  static void LogRegExpSource(Handle<JSRegExp> regexp);
+
+  // Emits a profiler tick event. Used by the profiler thread.
+  static void TickEvent(TickSample* sample, bool overflow);
+
+  static void ApiEvent(const char* name, ...);
+
+  // Logs a StringEvent regardless of whether FLAG_log is true.
+  static void UncheckedStringEvent(const char* name, const char* value);
+
+  // Stops logging and profiling in case of insufficient resources.
+  static void StopLoggingAndProfiling();
+
+  // Returns whether profiler's sampler is active.
+  static bool IsProfilerSamplerActive();
+
+  // The sampler used by the profiler and the sliding state window.
+  static Ticker* ticker_;
+
+  // When the statistical profile is active, profiler_
+  // points to a Profiler, that handles collection
+  // of samples.
+  static Profiler* profiler_;
+
+  // A stack of VM states.
+  static VMState* current_state_;
+
+  // Singleton bottom or default vm state.
+  static VMState bottom_state_;
+
+  // SlidingStateWindow instance keeping a sliding window of the most
+  // recent VM states.
+  static SlidingStateWindow* sliding_state_window_;
+
+  // An array of log events names.
+  static const char** log_events_;
+
+  // An instance of helper created if log compression is enabled.
+  static CompressionHelper* compression_helper_;
+
+  // Internal implementation classes with access to
+  // private members.
+  friend class CompressionHelper;
+  friend class EventLog;
+  friend class TimeLog;
+  friend class Profiler;
+  friend class SlidingStateWindow;
+  friend class VMState;
+
+  friend class LoggerTestHelper;
+
+  static bool is_logging_;
+#else
+  static bool is_logging() { return false; }
+#endif
+};
+
+
+// Class that extracts stack trace, used for profiling.
+class StackTracer : public AllStatic {
+ public:
+  static void Trace(TickSample* sample);
+};
+
+
+} }  // namespace v8::internal
+
+#endif  // V8_LOG_H_