orca/cstdlib/include/math.h

#ifndef _MATH_H
#define _MATH_H

#ifdef __cplusplus
extern "C" {
#endif

// NOTE(orca): not doing anything fancy for float_t and double_t
typedef float float_t;
typedef double double_t;

#define NAN       __builtin_nanf("")
#define INFINITY  __builtin_inff()

#define FP_NAN       0
#define FP_INFINITE  1
#define FP_ZERO      2
#define FP_SUBNORMAL 3
#define FP_NORMAL    4

int __fpclassify(double);
int __fpclassifyf(float);
int __fpclassifyl(long double);

static __inline unsigned __FLOAT_BITS(float __f)
{
	union {float __f; unsigned __i;} __u;
	__u.__f = __f;
	return __u.__i;
}
static __inline unsigned long long __DOUBLE_BITS(double __f)
{
	union {double __f; unsigned long long __i;} __u;
	__u.__f = __f;
	return __u.__i;
}

#define fpclassify(x) ( \
	sizeof(x) == sizeof(float) ? __fpclassifyf(x) : \
	sizeof(x) == sizeof(double) ? __fpclassify(x) : \
	__fpclassifyl(x) )

#define isinf(x) ( \
	sizeof(x) == sizeof(float) ? (__FLOAT_BITS(x) & 0x7fffffff) == 0x7f800000 : \
	sizeof(x) == sizeof(double) ? (__DOUBLE_BITS(x) & -1ULL>>1) == 0x7ffULL<<52 : \
	__fpclassifyl(x) == FP_INFINITE)

#define isnan(x) ( \
	sizeof(x) == sizeof(float) ? (__FLOAT_BITS(x) & 0x7fffffff) > 0x7f800000 : \
	sizeof(x) == sizeof(double) ? (__DOUBLE_BITS(x) & -1ULL>>1) > 0x7ffULL<<52 : \
	__fpclassifyl(x) == FP_NAN)

double      acos(double);

double      ceil(double);

double      cos(double);
float       cosf(float);

double      fabs(double);

double      floor(double);

double      fmod(double, double);

double      pow(double, double);

double      scalbn(double, int);

double      sin(double);
float       sinf(float);

double      sqrt(double);
float       sqrtf(float);

#define M_E             2.7182818284590452354   /* e */
#define M_LOG2E         1.4426950408889634074   /* log_2 e */
#define M_LOG10E        0.43429448190325182765  /* log_10 e */
#define M_LN2           0.69314718055994530942  /* log_e 2 */
#define M_LN10          2.30258509299404568402  /* log_e 10 */
#define M_PI            3.14159265358979323846  /* pi */
#define M_PI_2          1.57079632679489661923  /* pi/2 */
#define M_PI_4          0.78539816339744830962  /* pi/4 */
#define M_1_PI          0.31830988618379067154  /* 1/pi */
#define M_2_PI          0.63661977236758134308  /* 2/pi */
#define M_2_SQRTPI      1.12837916709551257390  /* 2/sqrt(pi) */
#define M_SQRT2         1.41421356237309504880  /* sqrt(2) */
#define M_SQRT1_2       0.70710678118654752440  /* 1/sqrt(2) */

#ifdef __cplusplus
}
#endif

#endif