PHP 7 ZendEngine thoughts


  • Those are internal engine changes ideas. Nothing here is about PHP userland API, but engine API/ABI.
  • Do not break if it is not needed.
  • Think about global changes, BC breaking, that could possibly be kept for about 10 years (we don't know yet if when will happen the next major)
  • Design clever, for good, not evil

Initial factors to be taken care of:

  • number of contributors
  • timetable (2 years development)
  • Cleanup API and dead code
    • Clear namings
    • Clear conventions between macros and functions
    • Clear those
  • Update dependencies.
    • Notably support Bison 3.0+.
  • Keep the extension-based build. Smaller pieces, better code maintaining
    • Merge SPL to the engine (at least, deep engine related stuff in SPL, such as the exception classes, the iterators and the functions like class_parents())
    • Rework Phar. Phar has too many engine hooks and voodoos, this must be rethought
  • Ehance extensions power
    • Keep distinction between zend extensions and php extensions ?
    • Use of other engine hooks ? other VM hooks ? (object store hooks, hashtable hooks ..? )
    • Remove old PHP4 support in ext code
    • Refactor error handler for extensions to be able to stack them like zend_execute
  • VM
    • Executor rewrite
    • Compiler rewrite
      • reentrant
      • AST based
      • Hookable AST for optimizer passes
    • OPCache integration
    • OPcode binary data based compiler (phalanger,, bcompiler, roadsend)
    • Create a flag to prevent separation of arguments in function calls ?
  • Arrays/Objects struct data sharing
    • Use array_* functions with objects or arrays
  • MM rewrite
    • Different pool sizes
    • Different heap allocators ? (jmalloc ?)
    • GC thoughts
  • Improve debug
    • Improve DTrace usage
    • Give Linux process-probes a try (SystempTap, perf, OProfile)
    • Add more debug level (we already have bunch of macros, such as “AGRESSIVE_DEBUG”)
ideas/php6/engine.txt · Last modified: 2014/08/15 15:41 by derick