Add a new API V8::SetJitCodeEventHandler to push code name and location to users such as profilers.

src/code-events.h

-// Copyright 2006-2008 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
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 // 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
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 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifndef V8_CODE_H_
-#define V8_CODE_H_
+#ifndef V8_CODE_EVENTS_H_
+#define V8_CODE_EVENTS_H_
 
 #include "allocation.h"
 
 namespace v8 {
 namespace internal {
 
+class CompilationInfo;
 
-// Wrapper class for passing expected and actual parameter counts as
-// either registers or immediate values. Used to make sure that the
-// caller provides exactly the expected number of parameters to the
-// callee.
-class ParameterCount BASE_EMBEDDED {
+class CodeEvents : public AllStatic {
  public:
-  explicit ParameterCount(Register reg)
-      : reg_(reg), immediate_(0) { }
-  explicit ParameterCount(int immediate)
-      : reg_(no_reg), immediate_(immediate) { }
-
-  bool is_reg() const { return !reg_.is(no_reg); }
-  bool is_immediate() const { return !is_reg(); }
-
-  Register reg() const {
-    ASSERT(is_reg());
-    return reg_;
-  }
-  int immediate() const {
-    ASSERT(is_immediate());
-    return immediate_;
+  static bool is_active() {
+    return event_handler_ != NULL;
   }
 
+  static void set_handler(JitCodeEventHandler event_handler) {
+    event_handler_ = event_handler;
+  }
+
+  // Code added notifications.
+  static void AddCode(const char* name,
+                      Code* code,
+                      Script* script,
+                      CompilationInfo* info);
+  static void AddCode(Handle<String> name,

[danno, 2012/07/25 13:50:42]

I find it a little odd that this interface takes both handles and raw pointers.
You probably should be uniform in the API, using all Handles or all pointers.
Since you call this from pointer-based code, you probably should keep everything
pointer-based, since calling handle-based APIs from pointer-based code is
generally not a good idea.

[Sigurður Ásgeirsson, 2012/07/25 14:38:35]

The interface here is substantially the same as the GDBJIT interface (with the
exception of removing the tag parameter). I did this to make it easy to tack the
GDBJIT code onto the JIT_CODE macros.

[Sigurður Ásgeirsson, 2012/07/27 13:25:24]

Added TODO to clean this up with the GDBJit fix.

+                      Handle<Script> script,
+                      Handle<Code> code,

[danno, 2012/07/25 13:50:42]

Order or parameters same? In fact, if both routines are pointer based, don't you
only need a single API call?

[Sigurður Ásgeirsson, 2012/07/25 14:38:35]

SGTM

+                      CompilationInfo* info);
+  static void AddCode(String* name, Code* code);
+  static void AddCode(const char* name, Code* code);
+  static void AddCode(Code* code);
+
+  // Code moved notification.
+  static void MoveCode(Address src, Address dst);
+
+  // Code removed notification.
+  static void RemoveCode(Code* code);
+
  private:
-  const Register reg_;
-  const int immediate_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(ParameterCount);
+  static JitCodeEventHandler event_handler_;
 };
 
+#define JIT_CODE_EVENT(action) \
+  do { if (CodeEvents::is_active()) CodeEvents::action; } while(0)
 
 } }  // namespace v8::internal
 
-#endif  // V8_CODE_H_
+#endif  // V8_CODE_EVENTS_H_