Re: [PATCH] No runtime fetching of built-in global constants

Hi Matt, Sorry if I missed it. Does this patch make any performance difference? I assume it saves on hash lookup during compilation and its really insignificant time. However it add new scanner rules which may slowdown the whole scanner. For now I don't see a big reason, but may be I didn't see something. Do you have any other "postponed" patches? I remember something about string optimizations and long multiply. Thanks. Dmitry. Matt Wilmas wrote:

Hi all, Never heard anything about this optimization after sending it 3 months ago (should've sent a follow-up sooner)... Is this something that can be done? Dmitry? Details in original message. Patch is unchanged, I just updated them for the current file versions. http://realplain.com/php/const_ct_optimization.diff http://realplain.com/php/const_ct_optimization_5_3.diff Thanks, Matt ----- Original Message ----- From: "Matt Wilmas" Sent: Friday, April 18, 2008

Hi all, I changed things so that the many "built-in" constants (CONST_PERSISTENT ones) will be replaced at compile-time, saving the FETCH_CONSTANT opcode,

if

these changes are usable. This was added for TRUE/FALSE/NULL 2 years ago, but seems like it can be done for "lots" of others too. Since the change 2 years ago, other constants have been getting looked up also, but just discarded. And if a constant wasn't found, its name was lowercased and looked up again (for case-insensitive TRUE/FALSE/NULL). Lowercasing has been removed, since case-insensitive constants can't be

done

(guess an exception was made for TRUE/FALSE/NULL :-)), and TRUE/FALSE/NULL get flagged in the scanner (not reserved words, which Marcus did briefly a few years ago), skipping a hash lookup. BTW, to get this compile-time optimization in a namespace, it needs to be prefixed (::CONSTANT). I also removed an unnecessary memcmp() in zend_get_constant() -- old code that was needed a long time ago, it appears. http://realplain.com/php/const_ct_optimization.diff http://realplain.com/php/const_ct_optimization_5_3.diff Thoughts? Thanks, Matt