Torbjörn Granlund tg at
Thu Mar 16 13:45:58 UTC 2017

nisse at (Niels Möller) writes:

  I think the "long double" type means an 80-bit floating point format
  which was implemented in the original 80387 floating point coprocessor.
  And which isn't supported by the later x86 SIMD instructions (and not
  supported at all on on non-x86 platforms, as far as I'm aware).
It is presumably the same as plain double almost everywhere.

We should probably not rely on FP arithmetic in GMP's generic code as it
is not predicatble enough.  Even if we do it just for IEEE 754, we can
not control the rounding mode.  That means that e.g., sqrt(2)^2 will be
greater that 2 sometimes, less than 2 sometimes.

Please encrypt, key id 0xC8601622

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