From d96fd33aa8a220d547512eb43c88fc8f5651e39e Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Sun, 27 Oct 2013 23:28:50 -0700 Subject: [PATCH] altos: Add sinf to math code Needed for the quaternion gyro tracking code Signed-off-by: Keith Packard --- src/math/math.h | 2 ++ src/math/sf_sin.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+) create mode 100644 src/math/sf_sin.c diff --git a/src/math/math.h b/src/math/math.h index c62f583d..fd543bc2 100644 --- a/src/math/math.h +++ b/src/math/math.h @@ -22,6 +22,8 @@ float acosf(float x); float cosf(float x); +float sinf(float x); + float sqrtf(float x); float fabsf(float x); diff --git a/src/math/sf_sin.c b/src/math/sf_sin.c new file mode 100644 index 00000000..da81845d --- /dev/null +++ b/src/math/sf_sin.c @@ -0,0 +1,62 @@ +/* sf_sin.c -- float version of s_sin.c. + * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + */ + +/* + * ==================================================== + * 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 "fdlibm.h" + +#ifdef __STDC__ + float sinf(float x) +#else + float sinf(x) + float x; +#endif +{ + float y[2],z=0.0; + __int32_t n,ix; + + GET_FLOAT_WORD(ix,x); + + /* |x| ~< pi/4 */ + ix &= 0x7fffffff; + if(ix <= 0x3f490fd8) return __kernel_sinf(x,z,0); + + /* sin(Inf or NaN) is NaN */ + else if (!FLT_UWORD_IS_FINITE(ix)) return x-x; + + /* argument reduction needed */ + else { + n = __ieee754_rem_pio2f(x,y); + switch(n&3) { + case 0: return __kernel_sinf(y[0],y[1],1); + case 1: return __kernel_cosf(y[0],y[1]); + case 2: return -__kernel_sinf(y[0],y[1],1); + default: + return -__kernel_cosf(y[0],y[1]); + } + } +} + +#ifdef _DOUBLE_IS_32BITS + +#ifdef __STDC__ + double sin(double x) +#else + double sin(x) + double x; +#endif +{ + return (double) sinf((float) x); +} + +#endif /* defined(_DOUBLE_IS_32BITS) */ -- 2.30.2