Re: PATCH: Fix the MIPS ISA ELF setting (Re: RedHat 7.1/mips update)

[Thiemo Seufer <ica2_ts at csv dot ica dot uni-stuttgart dot de>]

H . J . Lu wrote:
[snip]
> > Unfortunately the current behaviour of -mipsX is to select an
> > processor close to this ISA level. This is compatible with
> 
> I don't see that in the source code. It is only default to a particular
> processor for certain things if -march/-mtune is not used.
> 
> > traditional MIPS assemblers and older gas.

The older tools don't have -march/-mtune but rely on -mipsX.
Current gas tries to be compatible to old usage.

> > Giving it different
> > semantics instead of deprecating it will make things worse.
> > 
> 
> That is a news to me:
> 
> # as -help
> ...
> -mips1                  generate MIPS ISA I instructions
> -mips2                  generate MIPS ISA II instructions
> -mips3                  generate MIPS ISA III instructions
> -mips4                  generate MIPS ISA IV instructions
> -mips5                  generate MIPS ISA V instructions
> -mips32                 generate MIPS32 ISA instructions
> -mips64                 generate MIPS64 ISA instructions
> ...

Well, that's sort-of true. -mipsX allows the ISA's instructions
plus some processor specific ones (like e.g. eret).


Thiemo