Re: linux-2.3.3 doesn't boot when compiled with egcs-2.93.22

[Andi Kleen <ak at muc dot de>]

martin@mira.isdn.cs.tu-berlin.de (Martin v. Loewis) writes:

> > The only portable way to write memcpy is with `char*'; you can access
> > anything through a pointer-to-character.  But, to make it fast, you
> > probably have to write it in assembly code.
> 
> That's what I first thought, but it doesn't solve the problem
> completely.
> 
> The idea behind constant_memcpy is to have the compiler emit
> integer-moves for small amounts of data, and only use the x86 string
> operations for larger pieces of memory.
> 
> Now, that *could* be changed to use assembler code for the small
> structures as well, but then you'd lose optimization opportunities.
> AFAIK, you'd have to say that the asm changes "memory", whereas you
> clearly know that it changes *to. 

Another way is to fix __builtin_memcpy that it does the same stuff
as the Linux version, and then #ifdef out the string.h version for an appropiate
compiler version.

I guess it wouldn't be that hard. 


-Andi

-- 
This is like TV. I don't like TV.