Re: [win32gui] RE: [perl-win32-gui-hackers] T_HANDLE in the typemap

[Robert M. <rm...@po...>]

Jeremy White wrote:
>> Jeremy White wrote:
>>
>>> Just done some performance testing with this type map:
>>>
>>>    if(SvROK($arg)) {
>>>        SV** out=hv_fetch((HV*)SvRV($arg), \"-handle\", 7, 0);
>>>        if(out != NULL)
>>>            $var = ($type) SvIV(*out);
>>>        else
>>>            $var = NULL;
>>>    } else
>>>        $var = ($type) SvIV($arg);
>>>
>>> Benchmark: timing 1000000 iterations of NewTypeMap, OldTypeMap...
>>> NewTypeMap: 29 wallclock secs (29.64 usr +  0.06 sys = 29.70 CPU) @ 
>>> 33666.63/s (
>>> n=1000000)
>>> OldTypeMap: 38 wallclock secs (38.22 usr +  0.02 sys = 38.23 CPU) @ 
>>> 26154.05/s (
>>> n=1000000)
>>
>> I'm no typemap expert, but don't see anything wrong with that.  
>> Indeed, only doing the hv_fetch once seems like an obvious 
>> improvement.  If you can hold onto the code until after the next 
>> release, then we can get it into CVS for the following release?
> 
> No problem - there may be one issue. This code was compiled via Mingw, 
> and as I'm declaring SV** out within a block of code, VC will complain. 
> This may have been the reason that two hash reads were needed. I've a 
> copy of VC now, so once the current build is out of the way, I'll do 
> more testing.

I'm no C expert either, but I think it was always OK (C89 spec) to 
declare variables at the start of a block.  (I think it was the C99 spec 
that allowed you to declare a variable anywhere).  I think if it 
compiles with your somewhat old version of MinGW we'll be OK with VC98. 
  We'll try it once the next release is out of the way.

Regards,
Rob.