round and fmin/fmax are relatively commonly used functions but were not
implemented anywhere in the tcc Windows distribution package. Newer mingw(64)
math.h stil doesn't include these implementations.
Add C implementations for these functions and place it as inline functions at
win32/include/tcc/tcc_libm.h - which is already included from math.h .
The code is mostly taken from musl-libc rs-1.0 (MIT) [*],
musl-libc: http://git.musl-libc.org/cgit/musl/tree/src/math?h=rs-1.0
license: http://git.musl-libc.org/cgit/musl/tree/COPYRIGHT?h=rs-1.0
Potential enhancements:
- Check how many useful libm implementations are still missing and consider
adding them (some of them already work via the MS runtime).
- Consider putting libm implementations in an actual libm.a file, or add a dummy
one such that build processes which try to link with libm will not fail.
The asm code cannot currently be used with tcc since tcc doesn't support 't'
constraint.
Use inline C implementation instead, place it win32/include/tcc/tcc_libm.h, and
include it from win32/include/math.h.
Since fpclassify now works, it also fixes few other macros which depend on it.
Implicitly fixed: isfinite, isinf, isnan, isnormal.
The implementations were taken from musl-libc rs-1.0 (MIT license).
musl-libc: http://git.musl-libc.org/cgit/musl/tree/src/math?h=rs-1.0
license: http://git.musl-libc.org/cgit/musl/tree/COPYRIGHT?h=rs-1.0
