[fpc-pascal] Maybe one stupid question

Eduardo Morras emorras at xroff.net
Fri Jan 23 13:46:59 CET 2009

At 01:10 23/01/2009, you wrote:
>Hello FPC-Pascal,
>I'm using FPC 2.2.2 running over WinXP SP2. Are there any technical
>reasons that expains that a program runs faster using all checks ( I/O,
>Range, Overflow, Stack and Verify calls ) with optimization level 1
>and using heaptrace, than the same one compiled without any check,
>optimization level 2 or 3 and not using heaptrace ?

Perhaps your level 1 code fits in level 1-2 cache, and your level 2-3 
don't, causing more cache misses. Try to compile with -Os  instead 
level 1-2-3 and see if it's faster.

>I had expected around a 5% faster with the non-checks config, but I
>get a 2% slower program :-?
>Everything has been tested using Lazarus 1 month SVN, using a 1 minute
>runtime check.
>Best regards,
>  JoshyFun
>fpc-pascal maillist  -  fpc-pascal at lists.freepascal.org

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