Re: MIPS support for --with-arch-32 etc.

[Richard Sandiford <rdsandiford at googlemail dot com>]

Thanks for doing this.  Looks good.

"Joseph S. Myers" <joseph@codesourcery.com> writes:
> This patch adds support for the --with-arch-32 --with-arch-64
> --with-tune-32 --with-tune-64 configure options for MIPS.
>
> Because of the multiple MIPS ABIs, the meaning of such options is
> perhaps less obvious than for other processors - the approach I chose
> is that the -64 options are for ABIs requiring a 64-bit processor
> (ABI_NEEDS_64BIT_REGS), as the intended purpose of these options is to
> specify a 32-bit default processor for multilibs that may be run on
> non-64-bit processors and a 64-bit default processor for multilibs
> that can't run on non-64-bit processors.

Agreed, but I think this means that the dependency is really on
-mgp rather than -mabi.  This only makes a difference for -mabi=eabi,
because EABI has both 32-bit and 64-bit modes.  "-mabi=eabi -mgp32"
and "-mabi=eabi -mgp64" are both valid.

Since the default specs are (rightly) processed before the
default specs, I think this just means:

> +#if MIPS_ABI_DEFAULT == ABI_O64 \
> +  || MIPS_ABI_DEFAULT == ABI_N32 \
> +  || MIPS_ABI_DEFAULT == ABI_64
> +#define OPT_ARCH64 "mabi=32|mabi=eabi:;"
> +#define OPT_ARCH32 "mabi=32|mabi=eabi"

s/mabi=eabi/mgp32/ here

> +#else
> +#define OPT_ARCH64 "mabi=o64|mabi=n32|mabi=64"
> +#define OPT_ARCH32 "mabi=o64|mabi=n32|mabi=64:;"

and adding "|mgp64" here.

OK with those changes, thanks.

Richard