[L2Ork-dev] Double Precision project

[Giulio Moro]

I'd keep PD_FLOATSIZE, out of personal preference.

ARM: on arm, the NEON SIMD floating point unit flushes denormals to zero and is not slowed down by NaNs (although it doesn't flush them). The VFPv3 (on the Cortex-A8floating point unit by default keeps denormals and does slow computations on NaNs, however it can be put into flush-denormals-to-zero and fast-nan mode.
Not sure what happens with the more recent armv8 NEONs and VFPv4 though.

Giulio

________________________________________
From: L2Ork-dev <l2ork-dev-bounces at disis.music.vt.edu> on behalf of Jonathan Wilkes <jon.w.wilkes at gmail.com>
Sent: 08 May 2018 16:50
To: l2ork-dev
Subject: [L2Ork-dev] Double Precision project

Hi list,

We've merged one patch from Pranay's GSoC double precision project,
and I'll be merging another one soon:

https://git.purrdata.net/pranay_36/purr-data/commit/d0d6b54deb1b803c67d85bd5d123d3da98faf495

I'd like to raise a few questions before we get too deep into the project:

1. We're using a macro PD_FLOAT_PRECISION to make it possible to set
t_float precision at build time. This is the same macro katja used in
pd double, but I noticed Pd Vanilla changed this to PD_FLOATSIZE. Does
it matter? Related, should we go ahead and use the same macro as Pd
Vanilla here?

2. I'm not sure I understand the comment from the old code:

/* a test for NANs and denormals.  Should only be necessary on i386. */

How does x86_64 instruction set change things?

Also, what does ARM do here?

-Jonathan
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