Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
1. Previously, printing the number 1.0 could produce 0x1p+0, 0x2p-1,
0x4p-2, or 0x8p-3, depending on what happened to be convenient. This
meant that printing a value as a double and printing the same value
as a long double could produce different (but equivalent) results.
The change is to always make the leading digit a 1, unless the
number is 0. This solves the aforementioned problem and has
several other advantages.
2. Use the FPU to do rounding. This is far simpler and more portable
than manipulating the bits, and it fixes an obsure round-to-even
bug. It also raises the exceptions now required by IEEE 754R.
The drawbacks are that it is usually slightly slower, and it makes
printf less effective as a debugging tool when the FPU is hosed
(e.g., due to a buggy softfloat implementation).
3. On i386, twiddle the rounding precision so that (2) works properly
for long doubles.
4. Make several simplifications that are now possible due to (2).
5. Split __hldtoa() into a separate file.
Thanks to remko for access to a sparc64 box for testing.
instead use the FPU to convert subnormals to normals. (NB: Further
simplification is possible, such as using the FPU for the rounding
step.)
This fixes a bug reported by stefanf where long double subnormals in
the Intel 80-bit format would be output with one fewer digit than
necessary when the default precision was used.