1 Jul
2010
1 Jul
'10
5:09 p.m.
On Thu, Jul 1, 2010 at 10:41 AM, Stefan Westerfeld <stefan(a)space.twc.de> wrote:
Hi!
I am trying to fix a problem in beast, where an algorithm (subnormal
cancellation and the associated unit test) will work on "normal" computers,
but
not on AMD64, because denormals are treated as zero on this platform with the
compiler options we are using (-ffast-math and others).
So ideally I need a snippet of code (maybe assembler) that will just return
whether the processor/platform will have subnormals, like on x86, or not,
like on AMD64, by querying the processor status registers.
i don't have that, but ardour has libs/pbd/fpu.cc which does contain
code to determine if the processor has DAZ (denormals are zero).
libs/ardour/globals.cc has code to turn DAZ on.
--p