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-rw-r--r--src/math/e_rem_pio2.c163
1 files changed, 0 insertions, 163 deletions
diff --git a/src/math/e_rem_pio2.c b/src/math/e_rem_pio2.c
deleted file mode 100644
index 9eee36ae..00000000
--- a/src/math/e_rem_pio2.c
+++ /dev/null
@@ -1,163 +0,0 @@
-
-/* @(#)e_rem_pio2.c 1.4 95/01/18 */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunSoft, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
- * is preserved.
- * ====================================================
- *
- */
-
-/* __ieee754_rem_pio2(x,y)
- * 
- * return the remainder of x rem pi/2 in y[0]+y[1] 
- * use __kernel_rem_pio2()
- */
-
-#include <math.h>
-#include "math_private.h"
-
-/*
- * Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi 
- */
-static const int32_t two_over_pi[] = {
-0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62, 
-0x95993C, 0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A, 
-0x424DD2, 0xE00649, 0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129, 
-0xA73EE8, 0x8235F5, 0x2EBB44, 0x84E99C, 0x7026B4, 0x5F7E41, 
-0x3991D6, 0x398353, 0x39F49C, 0x845F8B, 0xBDF928, 0x3B1FF8, 
-0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D, 0x367ECF, 
-0x27CB09, 0xB74F46, 0x3F669E, 0x5FEA2D, 0x7527BA, 0xC7EBE5, 
-0xF17B3D, 0x0739F7, 0x8A5292, 0xEA6BFB, 0x5FB11F, 0x8D5D08, 
-0x560330, 0x46FC7B, 0x6BABF0, 0xCFBC20, 0x9AF436, 0x1DA9E3, 
-0x91615E, 0xE61B08, 0x659985, 0x5F14A0, 0x68408D, 0xFFD880, 
-0x4D7327, 0x310606, 0x1556CA, 0x73A8C9, 0x60E27B, 0xC08C6B, 
-};
-
-static const int32_t npio2_hw[] = {
-0x3FF921FB, 0x400921FB, 0x4012D97C, 0x401921FB, 0x401F6A7A, 0x4022D97C,
-0x4025FDBB, 0x402921FB, 0x402C463A, 0x402F6A7A, 0x4031475C, 0x4032D97C,
-0x40346B9C, 0x4035FDBB, 0x40378FDB, 0x403921FB, 0x403AB41B, 0x403C463A,
-0x403DD85A, 0x403F6A7A, 0x40407E4C, 0x4041475C, 0x4042106C, 0x4042D97C,
-0x4043A28C, 0x40446B9C, 0x404534AC, 0x4045FDBB, 0x4046C6CB, 0x40478FDB,
-0x404858EB, 0x404921FB,
-};
-
-/*
- * invpio2:  53 bits of 2/pi
- * pio2_1:   first  33 bit of pi/2
- * pio2_1t:  pi/2 - pio2_1
- * pio2_2:   second 33 bit of pi/2
- * pio2_2t:  pi/2 - (pio2_1+pio2_2)
- * pio2_3:   third  33 bit of pi/2
- * pio2_3t:  pi/2 - (pio2_1+pio2_2+pio2_3)
- */
-
-static const double
-zero =  0.00000000000000000000e+00, /* 0x00000000, 0x00000000 */
-half =  5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
-two24 =  1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
-invpio2 =  6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */
-pio2_1  =  1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */
-pio2_1t =  6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */
-pio2_2  =  6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */
-pio2_2t =  2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */
-pio2_3  =  2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */
-pio2_3t =  8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */
-
-int32_t __ieee754_rem_pio2(double x, double *y)
-{
-        double z,w,t,r,fn;
-        double tx[3];
-        int32_t e0,i,j,nx,n,ix,hx;
-        uint32_t low;
-
-        GET_HIGH_WORD(hx,x);            /* high word of x */
-        ix = hx&0x7fffffff;
-        if(ix<=0x3fe921fb)   /* |x| ~<= pi/4 , no need for reduction */
-            {y[0] = x; y[1] = 0; return 0;}
-        if(ix<0x4002d97c) {  /* |x| < 3pi/4, special case with n=+-1 */
-            if(hx>0) { 
-                z = x - pio2_1;
-                if(ix!=0x3ff921fb) {    /* 33+53 bit pi is good enough */
-                    y[0] = z - pio2_1t;
-                    y[1] = (z-y[0])-pio2_1t;
-                } else {                /* near pi/2, use 33+33+53 bit pi */
-                    z -= pio2_2;
-                    y[0] = z - pio2_2t;
-                    y[1] = (z-y[0])-pio2_2t;
-                }
-                return 1;
-            } else {    /* negative x */
-                z = x + pio2_1;
-                if(ix!=0x3ff921fb) {    /* 33+53 bit pi is good enough */
-                    y[0] = z + pio2_1t;
-                    y[1] = (z-y[0])+pio2_1t;
-                } else {                /* near pi/2, use 33+33+53 bit pi */
-                    z += pio2_2;
-                    y[0] = z + pio2_2t;
-                    y[1] = (z-y[0])+pio2_2t;
-                }
-                return -1;
-            }
-        }
-        if(ix<=0x413921fb) { /* |x| ~<= 2^19*(pi/2), medium size */
-            t  = fabs(x);
-            n  = (int32_t) (t*invpio2+half);
-            fn = (double)n;
-            r  = t-fn*pio2_1;
-            w  = fn*pio2_1t;    /* 1st round good to 85 bit */
-            if(n<32&&ix!=npio2_hw[n-1]) {       
-                y[0] = r-w;     /* quick check no cancellation */
-            } else {
-                uint32_t high;
-                j  = ix>>20;
-                y[0] = r-w; 
-                GET_HIGH_WORD(high,y[0]);
-                i = j-((high>>20)&0x7ff);
-                if(i>16) {  /* 2nd iteration needed, good to 118 */
-                    t  = r;
-                    w  = fn*pio2_2;     
-                    r  = t-w;
-                    w  = fn*pio2_2t-((t-r)-w);  
-                    y[0] = r-w;
-                    GET_HIGH_WORD(high,y[0]);
-                    i = j-((high>>20)&0x7ff);
-                    if(i>49)  { /* 3rd iteration need, 151 bits acc */
-                        t  = r; /* will cover all possible cases */
-                        w  = fn*pio2_3; 
-                        r  = t-w;
-                        w  = fn*pio2_3t-((t-r)-w);      
-                        y[0] = r-w;
-                    }
-                }
-            }
-            y[1] = (r-y[0])-w;
-            if(hx<0)    {y[0] = -y[0]; y[1] = -y[1]; return -n;}
-            else         return n;
-        }
-    /* 
-     * all other (large) arguments
-     */
-        if(ix>=0x7ff00000) {            /* x is inf or NaN */
-            y[0]=y[1]=x-x; return 0;
-        }
-    /* set z = scalbn(|x|,ilogb(x)-23) */
-        GET_LOW_WORD(low,x);
-        e0      = (ix>>20)-1046;        /* e0 = ilogb(z)-23; */
-	INSERT_WORDS(z, ix - ((int32_t)(e0<<20)), low);
-        for(i=0;i<2;i++) {
-                tx[i] = (double)((int32_t)(z));
-                z     = (z-tx[i])*two24;
-        }
-        tx[2] = z;
-        nx = 3;
-        while(tx[nx-1]==zero) nx--;     /* skip zero term */
-        n  =  __kernel_rem_pio2(tx,y,e0,nx,2,two_over_pi);
-        if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;}
-        return n;
-}