RFC & patch: Rework MIPS command-line handling

[Maciej W. Rozycki]

On Mon, 15 Jul 2002, Thiemo Seufer wrote:

> There seems to be some misconception about the term 'ABI', maybe
> because the current -mabi=FOO option basically means "select calling
> conventions and register sizes". But an ABI is a much more powerful
> concept than pushing a few compiler options. It defines a platform
> over a variety of hardware which allows to run the same binary code.

 As I already stated, the compromise might be to add an option to select
the code conventions regardless of the ABI and then make all the "-mabi="
options strict, i.e. select both a convention and an ISA and be
incompatible with both "-march=" and the convention selection option (bail
out if specified). 

> > I agree that might be true for embedded configs.  But like Maciej
> > said, it could be useful to have a default ABI for hosted toolchains
> > like mips64-linux-gnu.  It seems reasonable that anyone using such
> > an assembler would be at least try to write ABI-conformant code.
> 
> I don't know about embedded configs. Just have a look at the linux
> kernel. I claim it has nearly no assembly code which could be written
> in an ABI-conformant way, with few performance improvements in assembly
> as an exception.

 The kernel is special -- it's not a real target for a toolchain (it
doesn't even use PIC for MIPS).  Think e.g. glibc which uses assembly
directly here and there. 

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +