Re: [Linux-ia64] Using f6-f11 floating-point registers

[David Mosberger <davidm@hpl.hp.com>]

>>>>> On Tue, 27 Jun 2000 18:02:09 -0400, Jun Nakajima <jun@sco.com> said:

  Jun> At this point, the kernel is using more than f6-f11
  Jun> floating-point registers (using -mfixed-rangeñ0-f15,f32-f127,
  Jun> i.e. those are *not* available to the kernel, but the others,
  Jun> like f16-f31 are).

If the compiler or someone writing assembly code thinks it's
beneficial to use a preserved fp register, we should let them use it.
Of course, they'll have to explicitly save/restore the register before
using it, but there may well be cases where this is beneficial, so we
shouldn't prevent it for no good reason.

  Jun> When do we support the reduced FP model (EL_IA_64_REDUCEFP),
  Jun> where only f6-f11 are used by the kernel?

For the record, I have no plans to adopt the REDUCEFP model.  I want
to reserve the right for kernel developers to tweak the kernel
register usage without having to talk to a standards body.  Sorry.

	--david