Re: [coreboot] [patch][v2] remove inline functions in fam10 source

[Carl-Daniel Hailfinger]

On 25.04.2008 22:05, Marc Jones wrote:
> Segher Boessenkool wrote:
> > > Remove inline from FAM10 CPU initialization functions. This should
> > > save some ROM space.
>
> ....
> > > -static inline u32 read_cr4(void)
> > > +static u32 read_cr4(void)
> > >  {
> > >      u32 cr4;
> > >      __asm__ volatile ("movl %%cr4, %0" : "=r" (cr4));
> >
> > Things like these (not exhaustive) are usually *smaller* when inlined;
> > they compile to a single machine instruction (or two or so), and don't
> > have the space overhead for setting up a call (saving stuff to stack,
> > etc.)
> >
> > But don't take my word for it, just measure it after every change :-)
>
> Segher,
>
> Thanks for the comments. I think you are right about  _asm_ inline
> instructions should be smaller than a function call. It turns out that
> none of these changes resulted in a ROM size decrease with my tools.
> My guess is the GCC inlined them anyway.
>
> gcc version 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)
> GNU ld (GNU Binutils for Ubuntu) 2.18
>
> Here is a revised version of patch.

Thanks for doing this work!
> Remove inline from FAM10 CPU initialization functions.
> This doesn't save any space for me but it is the right thing to allow GCC to optimize.
>
> Signed-off-by: Marc Jones

Acked-by: Carl-Daniel Hailfinger

Regards,
Carl-Daniel