mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-18 10:35:55 +00:00
dab159e3d6
at runtime. etc/make.conf: Nuked HAVE_FPU option. lib/msun/Makefile: Always build the i387 objects. Copy the i387 source files at build time so that the i387 objects have different names. This is simpler than renaming the files in the cvs repository or repeating half of bsd.lib.mk to add explicit rules. lib/msun/src/*.c: Renamed all functions that have an i387-specific version by adding `__generic_' to their names. lib/msun/src/get_hw_float.c: New file for getting machdep.hw_float from the kernel. sys/i386/include/asmacros.h: Abuse the ENTRY() macro to generate jump vectors and associated code. This works much like PIC PLT dynamic initialization. The PIC case is messy. The old i387 entry points are renamed. Renaming is easier here because the names are given by macro expansions.
83 lines
2.0 KiB
C
83 lines
2.0 KiB
C
/* @(#)s_sin.c 5.1 93/09/24 */
|
|
/*
|
|
* ====================================================
|
|
* 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.
|
|
* ====================================================
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char rcsid[] = "$FreeBSD$";
|
|
#endif
|
|
|
|
/* sin(x)
|
|
* Return sine function of x.
|
|
*
|
|
* kernel function:
|
|
* __kernel_sin ... sine function on [-pi/4,pi/4]
|
|
* __kernel_cos ... cose function on [-pi/4,pi/4]
|
|
* __ieee754_rem_pio2 ... argument reduction routine
|
|
*
|
|
* Method.
|
|
* Let S,C and T denote the sin, cos and tan respectively on
|
|
* [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
|
|
* in [-pi/4 , +pi/4], and let n = k mod 4.
|
|
* We have
|
|
*
|
|
* n sin(x) cos(x) tan(x)
|
|
* ----------------------------------------------------------
|
|
* 0 S C T
|
|
* 1 C -S -1/T
|
|
* 2 -S -C T
|
|
* 3 -C S -1/T
|
|
* ----------------------------------------------------------
|
|
*
|
|
* Special cases:
|
|
* Let trig be any of sin, cos, or tan.
|
|
* trig(+-INF) is NaN, with signals;
|
|
* trig(NaN) is that NaN;
|
|
*
|
|
* Accuracy:
|
|
* TRIG(x) returns trig(x) nearly rounded
|
|
*/
|
|
|
|
#include "math.h"
|
|
#include "math_private.h"
|
|
|
|
#ifdef __STDC__
|
|
double __generic_sin(double x)
|
|
#else
|
|
double __generic_sin(x)
|
|
double x;
|
|
#endif
|
|
{
|
|
double y[2],z=0.0;
|
|
int32_t n, ix;
|
|
|
|
/* High word of x. */
|
|
GET_HIGH_WORD(ix,x);
|
|
|
|
/* |x| ~< pi/4 */
|
|
ix &= 0x7fffffff;
|
|
if(ix <= 0x3fe921fb) return __kernel_sin(x,z,0);
|
|
|
|
/* sin(Inf or NaN) is NaN */
|
|
else if (ix>=0x7ff00000) return x-x;
|
|
|
|
/* argument reduction needed */
|
|
else {
|
|
n = __ieee754_rem_pio2(x,y);
|
|
switch(n&3) {
|
|
case 0: return __kernel_sin(y[0],y[1],1);
|
|
case 1: return __kernel_cos(y[0],y[1]);
|
|
case 2: return -__kernel_sin(y[0],y[1],1);
|
|
default:
|
|
return -__kernel_cos(y[0],y[1]);
|
|
}
|
|
}
|
|
}
|