Re: [Mingw-users] CPU optimizations using -mcpu compiler option.

[Earnie B. <ear...@ya...>]

Sternbach, William [IT] wrote:
> Danny,
> 
> I run a long running number crunching program on my
> Pentium III 733 MHZ PC with 384 MB of Ram running
> Windows 2000 Professional and Mingw gcc version 3.2.
> 
> Currently I use the following compiler options:
> gcc -Wall -O3 -malign-double -s program.c -oprogram.exe
> 
> 1) Which -mcpu option should I use to get the fastest running
>     executables?
> 

-mcpu=i686 or -mcpu=pentiumpro

> 2) Are there other compiler options which you can recommend to
>     get faster running executables?
> 

You may want to play with -march if you are targeting only a specific 
set of ix86 hardware.  -march=i686 will create binaries that are only 
executable with that chip set.

You may want to look at -mms-bitfields to help with MS compatible data 
structure alignment.

Earnie.