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authorBruce Mitchener <bruce.mitchener@gmail.com>2014-01-15 09:57:37 +0700
committerBruce Mitchener <bruce.mitchener@gmail.com>2014-01-15 12:01:56 +0700
commitdb88b6cd9b687c3c88efd0e193ba8a97b0aef53d (patch)
tree3e5512a476741d5585b933444a34ef0adf285507 /system
parent60a86d0fcb15b8381f1fc97ad17571cb281f26c1 (diff)
Fill in undefined math symbols.
Diffstat (limited to 'system')
-rw-r--r--system/lib/libc/musl/src/math/__cos.c71
-rw-r--r--system/lib/libc/musl/src/math/__sin.c64
-rw-r--r--system/lib/libcextra.symbols2
3 files changed, 137 insertions, 0 deletions
diff --git a/system/lib/libc/musl/src/math/__cos.c b/system/lib/libc/musl/src/math/__cos.c
new file mode 100644
index 00000000..46cefb38
--- /dev/null
+++ b/system/lib/libc/musl/src/math/__cos.c
@@ -0,0 +1,71 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/k_cos.c */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+/*
+ * __cos( x, y )
+ * kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164
+ * Input x is assumed to be bounded by ~pi/4 in magnitude.
+ * Input y is the tail of x.
+ *
+ * Algorithm
+ * 1. Since cos(-x) = cos(x), we need only to consider positive x.
+ * 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0.
+ * 3. cos(x) is approximated by a polynomial of degree 14 on
+ * [0,pi/4]
+ * 4 14
+ * cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x
+ * where the remez error is
+ *
+ * | 2 4 6 8 10 12 14 | -58
+ * |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2
+ * | |
+ *
+ * 4 6 8 10 12 14
+ * 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then
+ * cos(x) ~ 1 - x*x/2 + r
+ * since cos(x+y) ~ cos(x) - sin(x)*y
+ * ~ cos(x) - x*y,
+ * a correction term is necessary in cos(x) and hence
+ * cos(x+y) = 1 - (x*x/2 - (r - x*y))
+ * For better accuracy, rearrange to
+ * cos(x+y) ~ w + (tmp + (r-x*y))
+ * where w = 1 - x*x/2 and tmp is a tiny correction term
+ * (1 - x*x/2 == w + tmp exactly in infinite precision).
+ * The exactness of w + tmp in infinite precision depends on w
+ * and tmp having the same precision as x. If they have extra
+ * precision due to compiler bugs, then the extra precision is
+ * only good provided it is retained in all terms of the final
+ * expression for cos(). Retention happens in all cases tested
+ * under FreeBSD, so don't pessimize things by forcibly clipping
+ * any extra precision in w.
+ */
+
+#include "libm.h"
+
+static const double
+C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
+C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
+C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
+C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
+C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
+C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
+
+double __cos(double x, double y)
+{
+ double_t hz,z,r,w;
+
+ z = x*x;
+ w = z*z;
+ r = z*(C1+z*(C2+z*C3)) + w*w*(C4+z*(C5+z*C6));
+ hz = 0.5*z;
+ w = 1.0-hz;
+ return w + (((1.0-w)-hz) + (z*r-x*y));
+}
diff --git a/system/lib/libc/musl/src/math/__sin.c b/system/lib/libc/musl/src/math/__sin.c
new file mode 100644
index 00000000..40309496
--- /dev/null
+++ b/system/lib/libc/musl/src/math/__sin.c
@@ -0,0 +1,64 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/k_sin.c */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+/* __sin( x, y, iy)
+ * kernel sin function on ~[-pi/4, pi/4] (except on -0), pi/4 ~ 0.7854
+ * Input x is assumed to be bounded by ~pi/4 in magnitude.
+ * Input y is the tail of x.
+ * Input iy indicates whether y is 0. (if iy=0, y assume to be 0).
+ *
+ * Algorithm
+ * 1. Since sin(-x) = -sin(x), we need only to consider positive x.
+ * 2. Callers must return sin(-0) = -0 without calling here since our
+ * odd polynomial is not evaluated in a way that preserves -0.
+ * Callers may do the optimization sin(x) ~ x for tiny x.
+ * 3. sin(x) is approximated by a polynomial of degree 13 on
+ * [0,pi/4]
+ * 3 13
+ * sin(x) ~ x + S1*x + ... + S6*x
+ * where
+ *
+ * |sin(x) 2 4 6 8 10 12 | -58
+ * |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2
+ * | x |
+ *
+ * 4. sin(x+y) = sin(x) + sin'(x')*y
+ * ~ sin(x) + (1-x*x/2)*y
+ * For better accuracy, let
+ * 3 2 2 2 2
+ * r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6))))
+ * then 3 2
+ * sin(x) = x + (S1*x + (x *(r-y/2)+y))
+ */
+
+#include "libm.h"
+
+static const double
+S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */
+S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */
+S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */
+S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */
+S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */
+S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */
+
+double __sin(double x, double y, int iy)
+{
+ double_t z,r,v,w;
+
+ z = x*x;
+ w = z*z;
+ r = S2 + z*(S3 + z*S4) + z*w*(S5 + z*S6);
+ v = z*x;
+ if (iy == 0)
+ return x + v*(S1 + z*r);
+ else
+ return x - ((z*(0.5*y - v*r) - y) - v*S1);
+}
diff --git a/system/lib/libcextra.symbols b/system/lib/libcextra.symbols
index 00dd899d..6f1039f1 100644
--- a/system/lib/libcextra.symbols
+++ b/system/lib/libcextra.symbols
@@ -1,3 +1,4 @@
+ T __cos
T __cosdf
T __fputwc_unlocked
T __intscan
@@ -9,6 +10,7 @@
C __optpos
D __optreset
W __posix_getopt
+ T __sin
T __sindf
T __strchrnul
T __strxfrm_l