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Re: standard runtime for (possible/hopeful) 64bit kernels

Paul Koning said;

if you want 64 bit
FP registers, then I agree N32 or N64 is the way to go.

n64 was invented to explore 64bit nature of post-R4000 processors;
- to have more arguments in registers passed to callee.
- to have 64bit integers in 64bit GP registers.
- same as 64bit FP in 64bit FP registers.

n32 is a particular variant of n64.  In kernel handling wise, the two
are identical each other.  And processor mode runs in the same,
including xtended TLB refill code path and the use fo  XTLBASE
register.  So, if NetBSD is going to have n64, n32 is realised instantly
w/o any further work.

For newer ABIs you need either a real
FPU, or compile everything with -msoftfloat if you don't have an FPU.
That's fine; softfloat is faster and cleaner than FP emulation.

Your point taken.

Toru Nishimura / ALKYL Technology

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