This is a experimental math lib based on musl libc, aiming at the determinism on all platforms. Different from musl libc, there are no code for a specific platform(like asm instructions).

Tag Dev: developping

Tag Finished: the branch finished its job, and is going to be deprecated

Main branch. Other developping branches are created based on this, and will finally merged into main.

Finished A test on mac showing that mac didn't turn off fma. Fixed.

Dev Test trigonometry operations using musl.

Finished Test basic operations like sum, without musl. Validates the stability of basic operations across platforms.

Finished Test + - * /, double to float across platforms.

Finished A version from determinism_asm_sin, uses the origin musl libc.

• Math functions: no implementations are changed. math.h, features.h, float.h are included as #include "".
• -1ULL: -1ULL and -1ULL>>1 are replaced by macros.
• features.h: add hidden definition, which is required by xxx_data.h and libm.h.

Simple tests with determinism_test.c. Tested on Windows11, 22H2, x64_64, AMD Ryzen Threadripper 3990X.

Cumulative error is found in the test. A small number equal to DBL_EPSILON is produced during the computation. For example, sqrt(2), the result of pow(sqrt(2), 2) is 2.0+2*DBL_EPSILON. The same phenomenon is found on the following compilers.

No problem.

No problem.

No problem.

Except for windows, CI in Github Actions tests this repo on:

Ubuntu 22.04, x64, gcc and clang

Ubuntu 22.04, x86 aarch64 armv7, gcc and clang

Macos 14, clang

Deleted ./arch: code for different platforms, file like fp_arch.h and float.h defines behavior for specific platforms. Deleted ./compat, ./crt, ./dist, ./ldso, ./tools: not related with math.

Modified ./include: only kept float.h, math.h, stdint.h, which are related to math.

Modified ./src: only kept folders related by math.h. ./src/include/features.h is included by math.h, kept. ./src/internal/libm.h is included by many math functions, kept. ./src/math, kept.

!! Deleted ./src/math/(some platform) folders: some functions (especially sqrt) have the corresponding assembly instruction on different platforms. These folders are deleted to make sure that all the functions are implemented by ourselves.

After deletion, I put the rest files like this:

./include
    | -- features.h
    | -- float.h
    | -- libm.h
    | -- math.h
    | -- stdint.h
./src
    | -- math
           | -- math function files

Deleted features.h: platform feature defines.

Deleted float.h, libm.h, stdint.h.

Modified math.h: paste code from float.h, libm.h, stdint.h.

Deletion: These functions for calculation are kept. input and output are double.

acos, asin, atan, atan2, ceil, cos, exp, fabs, floor, fmod, 
log, log10, log2, modf, pow, scalbn, sin, sqrt, tan, trunc

Internal functions like __cos.c, error handling functions like __math_invalid.c are kept.

Addition: functions for degree computation, reduction, factorial, gcd.

double degrees(double);
int    factorial(int);
double fsum(double*, int);
int    gcd(int, int);
double radians(double);

Modification: all files' include headers are changed. Files like cos.c including libm.h are changed to math.h. Files like __fpclassify.c including math.h, stdint.h are changed to math.h.