On Aug 6, 2015 1:49 PM, "Matt Wilmas" <php_li...@realplain.com> wrote: > > Hi Levi, > > > ----- Original Message ----- > From: "Levi Morrison" > Sent: Thursday, August 06, 2015 > >>> Don't know about Windows now... Visual Studio 2008 and 2012 (not much >>> difference) are NOT optimizing away the code (other times it was GCC with >>> issues). :-/ Not sure why. Of course they don't support the necessary >>> compound literals anyway, but I was just testing a manual case... I'll have >>> to try and check 2015 version soon. >> >> >> VS 2015 supports compound literals, I believe. > > > Yes, VS 2013 added, AFAIK. But I was just talking about optimizing the code that would use them. A compound literal (void *[]), derived from variadic macro, is needed to transform zend_parse_parameters() into a non-varargs inline function call (since va_arg usage prevents inlining). > > The problem in the earlier VS versions, which I simulated manually without compound literals, is that it doesn't want to optimize away all the inlined stuff, leaving only the result. Definitely can't have something creating several KB of extra instructions! :-) > > So unless they improved something in the newest versions, this wouldn't be able to be used there, unless I can work around it somehow. I don't know if macros, instead of inline functions, inside the main inline function would help or not... > > Although, it *would* simplify a couple tiny parts if didn't need to support MSVC... First, detecting a string *literal* (99% of usage): could just use __builtin_constant_p() instead of a macro trick. > > And second, using a variable length array, with size set by, well, a variable, which I think VS still doesn't support from C99, right? (It's for a "variable" in this case, but always the same, so should optimize like a compile-time size.)
If you have a piece of self contained code to test it, we can then add it to the VC test repo to valid what we can support with 7+.
