Re: Indy 64 or 32 bit?

[Ralf Baechle <ralf@oss.sgi.com>]

On Wed, Aug 08, 2001 at 11:02:44AM -0400, J. Scott Kasten wrote:

>    gcc -mips3 -mint64 test.c -o test
> 
> The file command says:
> 
>   test:           ELF N32 MSB mips-3 dynamic executable (not stripped) MIPS - version 1
> 
> Run:
> 
>   sizeof(int) = 8, sizeof(*) = 8
>   Result: 11
> 
> If we look at the assembly, we see a sign extended 64 bit load, and a 64
> bit add.  So we are indeed generating 64 bit instructions, at least in
> some cases.
> 
>         dli $3,0xa # 10
>         <snip>
>         daddu $3,$2,1
> 
> Does N32 legitimately allow 64 bit instructions,

Yes.  Hey, that's the 80% of the purpose of N32!

> or is this an example of code that I've truely "munged" togeather?

Doubleplusyesyesyes :-)  -mint64 is not valid for any MIPS code model.  Gas
is royally b0rken for N32.  If you really want to read about N32 get the
respective docs from techpubs.sgi.com.

  Ralf