[MIPS] reduce floating point registers

[Jim Wilson]

Shinpei Kato wrote:
> I want to reduce the number of floating point registers to 8 from 32.

All you have to do is mark the extra registers as fixed and call-used.
You can do this via the CONDITIONAL_REGISTER_USAGE macro.

I suspect your patch fails because you did not modify
REG_CLASS_CONTENTS, but you shouldn't try to fix this.  You should use
CONDITIONAL_REGISTER_USAGE instead.
-- 
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com