first commit of the new libm!

thanks to the hard work of Szabolcs Nagy (nsz), identifying the best
(from correctness and license standpoint) implementations from freebsd
and openbsd and cleaning them up! musl should now fully support c99
float and long double math functions, and has near-complete complex
math support. tgmath should also work (fully on gcc-compatible
compilers, and mostly on any c99 compiler).

based largely on commit 0376d44a890fea261506f1fc63833e7a686dca19 from
nsz's libm git repo, with some additions (dummy versions of a few
missing long double complex functions, etc.) by me.

various cleanups still need to be made, including re-adding (if
they're correct) some asm functions that were dropped.

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;
-}