about summary refs log tree commit diff
path: root/sysdeps/ieee754/dbl-64/dosincos.c
blob: 2a5f8fcc34bfe6498a1763fc5014643b63d511bc (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181

/*
 * IBM Accurate Mathematical Library
 * Copyright (c) International Business Machines Corp., 2001
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or 
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  
 */
/********************************************************************/
/*                                                                  */ 
/* MODULE_NAME: dosincos.c                                          */
/*                                                                  */
/*                                                                  */
/* FUNCTIONS:   dubsin                                              */
/*              dubcos                                              */
/*              docos                                               */
/* FILES NEEDED: endian.h mydefs.h dla.h dosincos.h                 */
/*               sincos.tbl                                         */
/*                                                                  */
/* Routines compute sin() and cos() as Double-Length numbers         */
/********************************************************************/



#include "endian.h"
#include "mydefs.h" 
#include "sincos.tbl"
#include "dla.h"
#include "dosincos.h"
/***********************************************************************/
/* Routine receive Double-Length number (x+dx) and computing sin(x+dx) */
/* as Double-Length number and store it at array v .It computes it by  */
/* arithmetic action on Double-Length numbers                          */
/*(x+dx) between 0 and PI/4                                            */      
/***********************************************************************/

void dubsin(double x, double dx, double v[]) {
  double xx,y,yy,z,zz,r,s,p,hx,tx,hy,ty,q,c,cc,d,dd,d2,dd2,e,ee,
    sn,ssn,cs,ccs,ds,dss,dc,dcc;
  mynumber u;
  int4 k;
  
  u.x=x+big.x;
  k = u.i[LOW_HALF]<<2;
  x=x-(u.x-big.x);
  d=x+dx;
  dd=(x-d)+dx;
         /* sin(x+dx)=sin(Xi+t)=sin(Xi)*cos(t) + cos(Xi)sin(t) where t ->0 */
  MUL2(d,dd,d,dd,d2,dd2,p,hx,tx,hy,ty,q,c,cc);
  sn=sincos.x[k];     /*                                  */
  ssn=sincos.x[k+1];  /*      sin(Xi) and cos(Xi)         */
  cs=sincos.x[k+2];   /*                                  */
  ccs=sincos.x[k+3];  /*                                  */
  MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc);  /* Taylor    */
  ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s); 
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);      /* series    */
  ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); 
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);      /* for sin   */
  MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,d,dd,ds,dss,r,s);                         /* ds=sin(t) */
  
  MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ;/* Taylor    */
  ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);      /* series    */
  ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);      /* for cos   */
  ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);      /* dc=cos(t) */
  
  MUL2(cs,ccs,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc);
  MUL2(dc,dcc,sn,ssn,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  SUB2(e,ee,dc,dcc,e,ee,r,s); 
  ADD2(e,ee,sn,ssn,e,ee,r,s);                    /* e+ee=sin(x+dx) */
  
  v[0]=e;
  v[1]=ee;
}
/**********************************************************************/
/* Routine receive Double-Length number (x+dx) and computes cos(x+dx) */
/* as Double-Length number and store it in array v .It computes it by */
/* arithmetic action on Double-Length numbers                         */
/*(x+dx) between 0 and PI/4                                           */
/**********************************************************************/

void dubcos(double x, double dx, double v[]) {
  double xx,y,yy,z,zz,r,s,p,hx,tx,hy,ty,q,c,cc,d,dd,d2,dd2,e,ee,
    sn,ssn,cs,ccs,ds,dss,dc,dcc;
  mynumber u;
  int4 k; 
  u.x=x+big.x; 
  k = u.i[LOW_HALF]<<2;
  x=x-(u.x-big.x);
  d=x+dx; 
  dd=(x-d)+dx;  /* cos(x+dx)=cos(Xi+t)=cos(Xi)cos(t) - sin(Xi)sin(t) */
  MUL2(d,dd,d,dd,d2,dd2,p,hx,tx,hy,ty,q,c,cc);  
  sn=sincos.x[k];     /*                                  */
  ssn=sincos.x[k+1];  /*      sin(Xi) and cos(Xi)         */
  cs=sincos.x[k+2];   /*                                  */
  ccs=sincos.x[k+3];  /*                                  */
  MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s); 
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); 
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,d,dd,ds,dss,r,s); 
  
  MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s); 
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  
  MUL2(cs,ccs,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc);
  MUL2(dc,dcc,sn,ssn,dc,dcc,p,hx,tx,hy,ty,q,c,cc);

  MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s);
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); 
  MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc);
  MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); 
  ADD2(ds,dss,d,dd,ds,dss,r,s); 
  MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s);
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s);
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s);
  MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  MUL2(sn,ssn,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc);
  MUL2(dc,dcc,cs,ccs,dc,dcc,p,hx,tx,hy,ty,q,c,cc);
  ADD2(e,ee,dc,dcc,e,ee,r,s); 
  SUB2(cs,ccs,e,ee,e,ee,r,s); 
 
  v[0]=e;
  v[1]=ee;
}
/**********************************************************************/
/* Routine receive Double-Length number (x+dx) and computes cos(x+dx) */
/* as Double-Length number and store it in array v                    */
/**********************************************************************/
void docos(double x, double dx, double v[]) {
  double y,yy,p,w[2];
  if (x>0) {y=x; yy=dx;}
     else {y=-x; yy=-dx;}
  if (y<0.5*hp0.x)                                 /*  y< PI/4    */
           {dubcos(y,yy,w); v[0]=w[0]; v[1]=w[1];}
     else if (y<1.5*hp0.x) {                       /* y< 3/4 * PI */
       p=hp0.x-y;  /* p = PI/2 - y */
       yy=hp1.x-yy;
       y=p+yy;
       yy=(p-y)+yy;
       if (y>0) {dubsin(y,yy,w); v[0]=w[0]; v[1]=w[1];}  
                                       /* cos(x) = sin ( 90 -  x ) */
         else {dubsin(-y,-yy,w); v[0]=-w[0]; v[1]=-w[1]; 
	 }
     }
  else { /* y>= 3/4 * PI */
    p=2.0*hp0.x-y;    /* p = PI- y */
    yy=2.0*hp1.x-yy;   
    y=p+yy;
    yy=(p-y)+yy;
    dubcos(y,yy,w);
    v[0]=-w[0];
    v[1]=-w[1];
  }
}