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



On Mon, Mar 16, 2009 at 03:10:11PM +1100, Simon Burge wrote:
 > > (I'm not currently clear on to what extent
 > > N32/N64 is coupled to the 64-bit FPU; if it is, we might end up
 > > wanting the O64 ABI...)
 > 
 > I'm not exactly sure what you mean by "64-bit FPU" - do you mean using
 > all 32 FP regs in 64-bit mode, instead of the 32 FP regs in 32-bit
 > "paired" mode?

Yes.

 > If so, n32 and n64 both use 32 FP regs in 64-bit mode
 > so both ABIs have the "full" FPU available.

Right; the (implicit) question is whether you can have N32 without
that FPU, as e.g. on a mips-II, or whether such machines have to build
userland, or at least anything using the FPU, as O32 or O64.

-- 
David A. Holland
dholland%netbsd.org@localhost


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