It is now possible to experiment with profiler guided optimizations when building V8. First build an instrumented sample shell:

  > scons pgo=instrument sample=shell

Then run the JavaScript code to optimize for using that sample shell. Finally build an optimized sample shell.

  > scons pgo=optimize sample=shell

Currently this does not work when building V8 as a DLL due to scons deleting v8.exp prior to the pgo=optimize step.

Due to a bug in Visual Studio (seen in version 2008) the function MessageDispatchHelperThread::Run() in debug.cc needs to be empty for this to work.
Review URL: http://codereview.chromium.org/652114

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3934 ce2b1a6d-e550-0410-aec6-3dcde31c8c00