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
|
/*
* IBM Accurate Mathematical Library
* Written by International Business Machines Corp.
* Copyright (C) 2001 Free Software Foundation, Inc.
*
* 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: branred.c */
/* */
/* FUNCTIONS: branred */
/* */
/* FILES NEEDED: branred.h mydefs.h endian.h mpa.h */
/* mha.c */
/* */
/* Routine branred() performs range reduction of a double number */
/* x into Double length number a+aa,such that */
/* x=n*pi/2+(a+aa), abs(a+aa)<pi/4, n=0,+-1,+-2,.... */
/* Routine returns the integer (n mod 4) of the above description */
/* of x. */
/*******************************************************************/
#include "endian.h"
#include "mydefs.h"
#include "branred.h"
#include "math_private.h"
/*******************************************************************/
/* Routine branred() performs range reduction of a double number */
/* x into Double length number a+aa,such that */
/* x=n*pi/2+(a+aa), abs(a+aa)<pi/4, n=0,+-1,+-2,.... */
/* Routine return integer (n mod 4) */
/*******************************************************************/
int __branred(double x, double *a, double *aa)
{
int i,k;
#if 0
int n;
#endif
mynumber u,gor;
#if 0
mynumber v;
#endif
double r[6],s,t,sum,b,bb,sum1,sum2,b1,bb1,b2,bb2,x1,x2,t1,t2;
x*=tm600.x;
t=x*split; /* split x to two numbers */
x1=t-(t-x);
x2=x-x1;
sum=0;
u.x = x1;
k = (u.i[HIGH_HALF]>>20)&2047;
k = (k-450)/24;
if (k<0)
k=0;
gor.x = t576.x;
gor.i[HIGH_HALF] -= ((k*24)<<20);
for (i=0;i<6;i++)
{ r[i] = x1*toverp[k+i]*gor.x; gor.x *= tm24.x; }
for (i=0;i<3;i++) {
s=(r[i]+big.x)-big.x;
sum+=s;
r[i]-=s;
}
t=0;
for (i=0;i<6;i++)
t+=r[5-i];
bb=(((((r[0]-t)+r[1])+r[2])+r[3])+r[4])+r[5];
s=(t+big.x)-big.x;
sum+=s;
t-=s;
b=t+bb;
bb=(t-b)+bb;
s=(sum+big1.x)-big1.x;
sum-=s;
b1=b;
bb1=bb;
sum1=sum;
sum=0;
u.x = x2;
k = (u.i[HIGH_HALF]>>20)&2047;
k = (k-450)/24;
if (k<0)
k=0;
gor.x = t576.x;
gor.i[HIGH_HALF] -= ((k*24)<<20);
for (i=0;i<6;i++)
{ r[i] = x2*toverp[k+i]*gor.x; gor.x *= tm24.x; }
for (i=0;i<3;i++) {
s=(r[i]+big.x)-big.x;
sum+=s;
r[i]-=s;
}
t=0;
for (i=0;i<6;i++)
t+=r[5-i];
bb=(((((r[0]-t)+r[1])+r[2])+r[3])+r[4])+r[5];
s=(t+big.x)-big.x;
sum+=s;
t-=s;
b=t+bb;
bb=(t-b)+bb;
s=(sum+big1.x)-big1.x;
sum-=s;
b2=b;
bb2=bb;
sum2=sum;
sum=sum1+sum2;
b=b1+b2;
bb = (ABS(b1)>ABS(b2))? (b1-b)+b2 : (b2-b)+b1;
if (b > 0.5)
{b-=1.0; sum+=1.0;}
else if (b < -0.5)
{b+=1.0; sum-=1.0;}
s=b+(bb+bb1+bb2);
t=((b-s)+bb)+(bb1+bb2);
b=s*split;
t1=b-(b-s);
t2=s-t1;
b=s*hp0.x;
bb=(((t1*mp1.x-b)+t1*mp2.x)+t2*mp1.x)+(t2*mp2.x+s*hp1.x+t*hp0.x);
s=b+bb;
t=(b-s)+bb;
*a=s;
*aa=t;
return ((int) sum)&3; /* return quater of unit circle */
}
|
