diff options
Diffstat (limited to 'src/math/sincosf.c')
| -rw-r--r-- | src/math/sincosf.c | 113 | 
1 files changed, 113 insertions, 0 deletions
| diff --git a/src/math/sincosf.c b/src/math/sincosf.c new file mode 100644 index 00000000..fede5f23 --- /dev/null +++ b/src/math/sincosf.c @@ -0,0 +1,113 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/s_sinf.c */ +/* + * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + * Optimized by Bruce D. Evans. + */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +#include "libm.h" + +/* Small multiples of pi/2 rounded to double precision. */ +static const double +s1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ +s2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ +s3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ +s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ + +void sincosf(float x, float *sin, float *cos) +{ +	double y, s, c; +	uint32_t n, hx, ix; + +	GET_FLOAT_WORD(hx, x); +	ix = hx & 0x7fffffff; + +	/* |x| ~<= pi/4 */ +	if (ix <= 0x3f490fda) { +		/* |x| < 2**-12 */ +		if (ix < 0x39800000) { +			/* raise inexact if x != 0 */ +			if((int)x == 0) { +				*sin = x; +				*cos = 1.0f; +			} +			return; +		} +		*sin = __sindf(x); +		*cos = __cosdf(x); +		return; +	} + +	/* |x| ~<= 5*pi/4 */ +	if (ix <= 0x407b53d1) {   +		if (ix <= 0x4016cbe3) {  /* |x| ~<= 3pi/4 */ +			if (hx < 0x80000000) { +				*sin = __cosdf(x - s1pio2); +				*cos = __sindf(s1pio2 - x); +			} else { +				*sin = -__cosdf(x + s1pio2); +				*cos = __sindf(x + s1pio2); +			} +			return; +		} +		*sin = __sindf(hx < 0x80000000 ? s2pio2 - x : -s2pio2 - x); +		*cos = -__cosdf(hx < 0x80000000 ? x - s2pio2 : x + s2pio2); +		return; +	} + +	/* |x| ~<= 9*pi/4 */ +	if (ix <= 0x40e231d5) { +		if (ix <= 0x40afeddf) {  /* |x| ~<= 7*pi/4 */ +			if (hx < 0x80000000) { +				*sin = -__cosdf(x - s3pio2); +				*cos = __sindf(x - s3pio2); +			} else { +				*sin = __cosdf(x + s3pio2); +				*cos = __sindf(-s3pio2 - x); +			} +			return; +		} +		*sin = __sindf(hx < 0x80000000 ? x - s4pio2 : x + s4pio2); +		*cos = __cosdf(hx < 0x80000000 ? x - s4pio2 : x + s4pio2); +		return; +	} + +	/* sin(Inf or NaN) is NaN */ +	if (ix >= 0x7f800000) { +		*sin = *cos = x - x; +		return; +	} + +	/* general argument reduction needed */ +	n = __rem_pio2f(x, &y); +	s = __sindf(y); +	c = __cosdf(y); +	switch (n&3) { +	case 0: +		*sin = s; +		*cos = c; +		break; +	case 1: +		*sin = c; +		*cos = -s; +		break; +	case 2: +		*sin = -s; +		*cos = -c; +		break; +	case 3: +	default: +		*sin = -c; +		*cos = s; +		break; +	} +} | 
