[fpc-devel] Patch for rtl/inc/rtti.inc

[Florian Klaempfl]

Daniël Mantione schrieb:
> 
> 
> Op Sun, 14 Sep 2008, schreef Jonas Maebe:
> 
>>
>> On 14 Sep 2008, at 14:49, Markus Beth wrote:
>>
>>> this patch rewrites code of ArrayRTTI and fpc_Copy to allow the 
>>> compiler to generate faster code (at least on i386).
>>> The change in ArrayRTTI yields a performance gain of ~4% for our real 
>>> world application on a 3 GHz Intel Xeon.
>>> The change in fpc_Copy is completely untestet because I don't know 
>>> when this compilerproc is called. Maybe someone who knows can hack a 
>>> quick benchmark...
>>
>> I don't think it's a good idea to start manually adding loop induction 
>> variables to many routines in the rtl. It makes the code less 
>> maintainable, and at one point the compilation process itself 
>> will/should do that by itself.
> 
> This patch should get applied. It's debatable wether additions are hard 
> to maintain than multiplications and it may take years before the 
> compiler can do that optimization. That doesn't mean we should optimize 
> anything manually, but fpc_copy is definately speed critical code for 
> things like widestrings.

Shall I implement automatic simple loop induction variable tonight :)?