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

Hi Matt, I updated your patch a little bit to make it more clear (from my point of view). Please take a look. Thanks. Dmitry. Matt Wilmas wrote: > Hi Dmitry, > > Well, it's been awhile since Alpha 1 :-), so I wanted to finally resend this > before Alpha 2! I agree that the additional optimization probably wouldn't > happen often, as there won't be that much namespace usage right away, I > assume. But I think it makes sense to handle :: prefix constants, since > they're known to have global scope, and I can see the future [online] > optimization tip: "When using namespaces, use :: for global constants to get > compile-time substitution." ;-) > > The code is the same as before, just updated the patch. It doesn't really > seem less clear, to me, than the current code. In zend_do_fetch_constant(), > the "check_namespace" variable may be better named something like > "from_namespace" according to my changes, to be more clear, but I left that > out to make the patch as simple as possible. > > http://realplain.com/php/ct_const_fixes.diff > http://realplain.com/php/ct_const_fixes_5_3.diff > > > Thanks, > Matt > > > ----- Original Message ----- > From: "Dmitry Stogov" > Sent: Thursday, July 31, 2008 > >> Hi Matt, >> >> Now I know. :) >> Anyway, I don't think this optimization will work often. >> >> Send me the patch after Alpha1 release. >> >> Thanks. Dmitry. >> >> >> Matt Wilmas wrote: >>> Hi Dmitry, >>> >>> Do you know that with your changes, no substitution will happen in a >>> namespace even when using :: prefix? :-/ (That's what I would do when I >>> know it's global, for optimization.) Or is that what you meant by "not > so >>> optimal?" >>> >>> >>> - Matt >>> >>> >>> ----- Original Message ----- >>> From: "Dmitry Stogov" >>> Sent: Thursday, July 31, 2008 >>> >>>> Thanks Matt. I committed near the same patch. >>>> It's not so optimal, but little bit more clear. >>>> >>>> Thanks. Dmitry. >>>> >>>> Matt Wilmas wrote: >>>>> Hi Dmitry, >>>>> >>>>> For the behavior change that I mentioned in the other thread, with > this >>>>> code: >>>>> >>>>> function foo() { >>>>> static $a = -PHP_INT_MAX; >>>>> } >>>>> >>>>> Which could work sometimes, and sometimes not (if in a namespace or >>>>> ZEND_COMPILE_NO_CONSTANT_SUBSTITUTION is set). I changed things so > that >>>>> there is no substitution of constants (except with CT_SUBST flag, like >>>>> always) for compile time constants (ZEND_CT mode). They don't create > a >>>>> FETCH_CONSTANT opcode anyway. :-) >>>>> >>>>> Another thing I realized wasn't getting optimized (runtime constants), >>> which >>>>> can be, is with: >>>>> >>>>> namespace foo; >>>>> $a = ::PHP_INT_MAX; // :: for global scope >>>>> >>>>> So the patch allows substitution there as well. >>>>> >>>>> http://realplain.com/php/ct_const_fixes.diff >>>>> >>>>> http://realplain.com/php/ct_const_fixes_5_3.diff >