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

src/code-events.cc

+// Copyright 2012 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.
+
+#include "v8.h"
+
+#include "code-events.h"
+
+namespace v8 {
+namespace internal {
+
+static const char* CodeKindToString(Code::Kind kind) {
+  switch (kind) {
+#define DEF_CASE(name) case Code::name: return #name;
+    CODE_KIND_LIST(DEF_CASE)
+#undef DEF_CASE
+    default:
+      return "*UNKNOWN*";
+  } 
+}
+
+JitCodeEventHandler CodeEvents::event_handler_ = NULL;
+
+
+void CodeEvents::AddCode(const char* name,
+                         Code* code,
+                         Script* script,
+                         CompilationInfo* info) {
+  JitCodeEvent event = { JitCodeEvent::CODE_ADDED,
+                         code->instruction_start(), 
+                         code->instruction_size() };
+  event.name = name;
+  event_handler_(&event);
+}
+
+
+void CodeEvents::AddCode(Handle<String> name,
+                         Handle<Script> script,
+                         Handle<Code> code,
+                         CompilationInfo* info) {
+  if (!name.is_null()) {
+    SmartArrayPointer<char> name_cstring = name->ToCString(DISALLOW_NULLS);
+    AddCode(*name_cstring, *code, *script, info);
+  } else {
+    AddCode("", *code, *script, info);
+  }
+}
+
+
+void CodeEvents::AddCode(String* name, Code* code) {
+  AddCode(name != NULL ? *name->ToCString(DISALLOW_NULLS) : NULL, code);
+}
+
+
+void CodeEvents::AddCode(const char* name, Code* code) {
+  EmbeddedVector<char, 256> buffer;
+  StringBuilder builder(buffer.start(), buffer.length());
+
+  builder.AddString(CodeKindToString(code->kind()));
+  if ((name != NULL) && (*name != '\0')) {
+    builder.AddString(": ");
+    builder.AddString(name);
+  } else {
+    builder.AddFormatted(": code object %p", static_cast<void*>(code));
+  }
+
+  AddCode(builder.Finalize(), code, NULL, NULL);
+}
+
+
+void CodeEvents::AddCode(Code* code) {

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

Can you handle this with default parameters with a single AddCode API?

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

I imagine I can, do you mind if I fold that into a second CL with a fix to the
GDBJIT code?

+  AddCode("", code);
+}
+
+void CodeEvents::MoveCode(Address src, Address dst) {
+  Code* src_code = Code::cast(HeapObject::FromAddress(src));
+  
+  JitCodeEvent event = { JitCodeEvent::CODE_MOVED,
+                         src_code->instruction_start(),
+                         src_code->instruction_size() };
+
+  // Calculate the header size.
+  const size_t header_size =
+      src_code->instruction_start() - reinterpret_cast<byte*>(src_code);
+
+  event.new_code_start = dst + header_size;
+  
+  event_handler_(&event);
+}
+
+
+void CodeEvents::RemoveCode(Code* code) {
+  JitCodeEvent event = { JitCodeEvent::CODE_REMOVED,
+                         code->instruction_start(),
+                         code->instruction_size() };
+
+  event_handler_(&event);
+}
+
+
+} }  // namespace v8::internal