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authormrb0nk500 <b0nk@b0nk.xyz>2023-02-02 17:29:19 -0400
committermrb0nk500 <b0nk@b0nk.xyz>2023-02-03 13:27:06 -0400
commitf2eabdb6257c09cf2890dac5e9737912728542af (patch)
tree3b46f6787185d65605651a0f48776dc9779ce648 /src/MSL_C.PPCEABI.bare.H/k_sin.c
parenteef1dd840b7cecac28c2e6b0574707b90a37d4e7 (diff)
global: Add rest of Dolphin SDK proper, add MSL, and MetroTRK
Finally, it links properly.
Diffstat (limited to 'src/MSL_C.PPCEABI.bare.H/k_sin.c')
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1 files changed, 79 insertions, 0 deletions
diff --git a/src/MSL_C.PPCEABI.bare.H/k_sin.c b/src/MSL_C.PPCEABI.bare.H/k_sin.c
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+/* @(#)k_sin.c 1.2 95/01/04 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+/* __kernel_sin( x, y, iy)
+ * kernel sin function on [-pi/4, pi/4], 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. if x < 2^-27 (hx<0x3e400000 0), return x with inexact if x!=0.
+ * 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 "fdlibm.h"
+
+#ifdef __STDC__
+static const double
+#else
+static double
+#endif
+ half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
+ 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 */
+
+#ifdef __STDC__
+double __kernel_sin(double x, double y, int iy)
+#else
+double __kernel_sin(x, y, iy)
+double x, y;
+int iy; /* iy=0 if y is zero */
+#endif
+{
+ double z, r, v;
+ int ix;
+ ix = __HI(x) & 0x7fffffff; /* high word of x */
+ if (ix < 0x3e400000) /* |x| < 2**-27 */
+ {
+ if ((int)x == 0)
+ return x;
+ } /* generate inexact */
+ z = x * x;
+ v = z * x;
+ r = S2 + z * (S3 + z * (S4 + z * (S5 + z * S6)));
+ if (iy == 0)
+ return x + v * (S1 + z * r);
+ else
+ return x - ((z * (half * y - v * r) - y) - v * S1);
+}