[fpc-devel] CompareMem slower in FPC 2.4.4

Michalis Kamburelis michalis.kambi at gmail.com
Fri Jun 3 03:06:02 CEST 2011


Florian Klämpfl wrote:
> Am 01.06.2011 22:07, schrieb Michalis Kamburelis:
>> Hi,
>>
>> In my tests, FPC 2.4.4 has much slower CompareMem than FPC 2.4.2, at
>> least for some cases:
> 
> I've commited an improved version in r17642

That's great :) I just tested with fpc from SVN (rev 17644), and can
confirm that CompareMem is much faster now. It beats CompareMem from
both FPC 2.4.4 and FPC 2.4.2:

FPC 2.4.2: 2.635s
FPC 2.4.4: 16.803s
FPC trunk: 1.931s

Although it's still slightly slower than comparing directly with "(V1[0]
= V2[0]) and ...", which is ~1.2s for all 3 FPC versions mentioned
above. I guess there has to be some price for CompareMem being more
general, and checking size at runtime.

Thanks everyone,
Michalis



More information about the fpc-devel mailing list