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Re: armelfp: new architecture name for an armel variant

On 09/07/10 21:40, Paul Brook wrote:
> There are several variants of VFPv3. Some have the additional registers 
> (typically the implementations that also have NEON), some do not. VFPv3 also 
> introduces some new instructions, so even the variants with the restricted 
> register file will not work on VFPv2 hardware (e.g. arm11).
> You mean VFPv3 v.s. VFPv2? Saying ARMv7 when you actually mean a particular 
> FPU is extremely unhelpful.

Indeed; I've only ever experienced one variant of VFPv3 on ARMv7 devices
and assumed it was mandated in the spec. (And I didn't want to get in to
the horrible maze of VFP variants.)

This just makes it even more important that any hypothetical FPU-based
Debian variant thinks very, very carefully about the ABI it uses. There
is a standard EABI variant for passing parameters in FPU registers ---
but is it sufficiently common to be useful in a cross-platform OS? Are
there devices that claim to support VFP that *don't* support this ABI?

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