diff options
| author | Ian Moffett <ian@osmora.org> | 2025-07-14 22:39:34 -0400 |
|---|---|---|
| committer | Ian Moffett <ian@osmora.org> | 2025-07-14 23:27:58 -0400 |
| commit | 30634165980deaeead9f4e71e0ff6a5c9d897776 (patch) | |
| tree | 18546a9d493a699eb3ea23ab5cc792d40cf82d7d /lib/libc/src/musl-math/acoshf.c | |
| parent | 83acdbef7ae961c2ae296835df3f368573c89eeb (diff) | |
usr: libc: Add math.h + musl math impl portexpt
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'lib/libc/src/musl-math/acoshf.c')
| -rw-r--r-- | lib/libc/src/musl-math/acoshf.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/lib/libc/src/musl-math/acoshf.c b/lib/libc/src/musl-math/acoshf.c new file mode 100644 index 0000000..8a4ec4d --- /dev/null +++ b/lib/libc/src/musl-math/acoshf.c @@ -0,0 +1,26 @@ +#include "libm.h" + +#if FLT_EVAL_METHOD==2 +#undef sqrtf +#define sqrtf sqrtl +#elif FLT_EVAL_METHOD==1 +#undef sqrtf +#define sqrtf sqrt +#endif + +/* acosh(x) = log(x + sqrt(x*x-1)) */ +float acoshf(float x) +{ + union {float f; uint32_t i;} u = {x}; + uint32_t a = u.i & 0x7fffffff; + + if (a < 0x3f800000+(1<<23)) + /* |x| < 2, invalid if x < 1 or nan */ + /* up to 2ulp error in [1,1.125] */ + return log1pf(x-1 + sqrtf((x-1)*(x-1)+2*(x-1))); + if (a < 0x3f800000+(12<<23)) + /* |x| < 0x1p12 */ + return logf(2*x - 1/(x+sqrtf(x*x-1))); + /* x >= 0x1p12 */ + return logf(x) + 0.693147180559945309417232121458176568f; +} |