[MIPS] Avoiding FP operations/register usage

[Richard Sandiford]

Matthew Fortune <Matthew.Fortune@imgtec.com> writes:
> I'm still interested in how successfully the MIPS backend is managing to
> avoid floating point but I am also convinced there are bugs in ld.so
> entry points for MIPS.

It uses the standard mechanism to avoid it, which is marking uses of
FP registers for integer moves, loads and stores with "*".  This tells
the register allocator to ignore those alternatives.  AFAIK it is
effective and I think any cases where it doesn't work would be fair
bug reports.

It becomes a lot more difficult to define with things like the Loongson
extensions though, since some of those are also useful as scalar integer
operations.  And of course the same goes for MSA.

Thanks,
Richard