Something based on this may finally land, since Intel is helping out with vtune integration. The API needs some further changes to handle chunked compilation. (I've been using this patch for several months now with gdb/jit and recently vtune.)
Created attachment 617100 [details] [diff] [review] Convert JIT registration API to use JITChunks nearly everywhere in place of JITScripts.
Sorry, I backed out this bug and bug 730208: https://hg.mozilla.org/integration/mozilla-inbound/rev/cecc9064c6cb because one of them apparently caused crashes in xpcshell tests on debug builds: https://tbpl.mozilla.org/php/getParsedLog.php?id=11180559&tree=Mozilla-Inbound