Re: [PATCH 28/30] configure, meson.build: Mark support for 64-bit LoongArch hosts

[WANG Xuerui]

Hi Philippe,

On 9/21/21 14:59, Philippe Mathieu-Daudé wrote:
> On 9/21/21 08:02, WANG Xuerui wrote:
> > On 9/21/21 01:23, Richard Henderson wrote:
> > > On 9/20/21 1:04 AM, WANG Xuerui wrote:
> > > > Signed-off-by: WANG Xuerui <git@xen0n.name>
> > > > ---
> > > >   configure   | 4 +++-
> > > >   meson.build | 4 +++-
> > > >   2 files changed, 6 insertions(+), 2 deletions(-)
>
> > > If there's no loongarch32, and never will be, then there's probably 
> > > no point in keeping the '64' suffix.
> >
> > The loongarch32 tuple will most certainly come into existence some 
> > time in the future, but probably bare-metal-only and without a Linux 
> > port AFAIK. That's a point the Loongson people and I didn't 
> > communicate well, apologizes for that. (While we're at it, the 
> > reserved "loongarchx32" which is x32/n32-like, most likely will never 
> > exist.)
>
> Are you trying to beat MIPS at their ABI complexity? /s

Hah, I'm not Loongson employee so maybe I'm not in the best position to 
answer this ;-)

But from an outsider's perspective, the Loongson people obviously 
reserved things upfront like a multi-millionaire, then suddenly realized 
they only have ~500 people on board, developers even less; so they did 
the Right Thing(TM), only later, to drop x32 altogether and focus their 
energy on bare-metal use cases for their 32-bit-only chips.

Plus, LoongArch is strictly little-endian, and only one baseline ISA 
revision is published so far, so IMO it can never beat MIPS in terms of 
combinatorial ABI possibilities. Maybe RISC-V have a chance? ;-)