This was the last remaining GNU assembler code that was in its own
independent source file, as opposed to being embedded in C code with
GNU `__asm__ volatile` or MSVC `__asm` (which tends to be much easier
to deal with in a modern build system).
When the Quake 3 engine was originally written, this might have been
an "expensive" function when written in portable C, but after 25 years
of CPU development it's less likely to matter (and modern compilers
might produce faster results from the C code anyway).
Resolves: https://github.com/ioquake/ioq3/issues/778
Signed-off-by: Simon McVittie <smcv@debian.org>
Before commit a7d33b1c "(bug #3639) BoxOnPlaneSide rewrite" there
was more code here, but since then the only thing left is the
Invert24To16 function, to which I couldn't find any references since
the beginning of ioquake3's git history.
Resolves: https://github.com/ioquake/ioq3/issues/774
Signed-off-by: Simon McVittie <smcv@debian.org>