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Re: armelfp: new architecture name for an armel variant

On 2010-07-06 21:55, Loïc Minier wrote:
  I would be a bit scared that this has a chance of getting out of date,
  or be confusing because other ports might be v7 as well, or also
  because this only reflects a subset of the ports' requirement (VFP
  level for instance isn't reflected, such as vfpv2, vfpv3).

ARMv7 (which I think is VFPv3) has 64 quads-worth of floating point registers (64 singles or 32 doubles). Earlier versions have 32 (32 singles or 16 doubles). The calling convention doesn't change --- d0-d7 (s0-s15) are used for parameter passing, and everything else are callee-saves scratch registers.

This means that code built for ARMv7 will mostly work on ARMv6 and before, but if it happens to use more than a certain number of registers it'll fail in really odd ways.

┌─── dg@cowlark.com ───── http://www.cowlark.com ─────
│ life←{ ↑1 ⍵∨.^3 4=+/,¯1 0 1∘.⊖¯1 0 1∘.⌽⊂⍵ }
│ --- Conway's Game Of Life, in one line of APL

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