Re: Possibility of adding -march=native to x86

[Michael Lothian]

On 25/10/2007, Gabriel C <nix.or.die@xxxxxxxxxxxxxx> wrote:
> Michael Lothian wrote:
> >> The MPENTIUM4 option does not only set -march=pentium4, it also enables
> >> several other options in arch/i386/Kconfig.cpu resulting in better
> >> performance.
> >
> > How about an autodetect to set the right options here too using cpuid?
> >
> > With a warning of course that the code produced will be specifically
> > for the native cpu that it's compiled on.
>
> And kill off all Distro kernels right ? IMO to set that auto magically is bad.
>
> Regards,
>
> Gabriel
>
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Yes for something like a distro kernel it is bad but as I said before
this isn't what this is for.

Eventually it would be nice to to a make localkernel and for a
customised kernel to be build compiling in all pci / pci express
drivers into the kernel and all usb devices as modules.

Auto magically detecting the cpu would be part of that

I hate getting a new piece of kit and then have to figure out from
lspci which options need to be turned on and the the really iritation
part of finding the option in make menuconfig

Detecting the cpu and using march=native could be all part of that

Mike
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