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-rw-r--r--libc-top-half/musl/src/math/sincos.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/math/sincos.c b/libc-top-half/musl/src/math/sincos.c
new file mode 100644
index 0000000..35b2d92
--- /dev/null
+++ b/libc-top-half/musl/src/math/sincos.c
@@ -0,0 +1,69 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/s_sin.c */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#define _GNU_SOURCE
+#include "libm.h"
+
+void sincos(double x, double *sin, double *cos)
+{
+ double y[2], s, c;
+ uint32_t ix;
+ unsigned n;
+
+ GET_HIGH_WORD(ix, x);
+ ix &= 0x7fffffff;
+
+ /* |x| ~< pi/4 */
+ if (ix <= 0x3fe921fb) {
+ /* if |x| < 2**-27 * sqrt(2) */
+ if (ix < 0x3e46a09e) {
+ /* raise inexact if x!=0 and underflow if subnormal */
+ FORCE_EVAL(ix < 0x00100000 ? x/0x1p120f : x+0x1p120f);
+ *sin = x;
+ *cos = 1.0;
+ return;
+ }
+ *sin = __sin(x, 0.0, 0);
+ *cos = __cos(x, 0.0);
+ return;
+ }
+
+ /* sincos(Inf or NaN) is NaN */
+ if (ix >= 0x7ff00000) {
+ *sin = *cos = x - x;
+ return;
+ }
+
+ /* argument reduction needed */
+ n = __rem_pio2(x, y);
+ s = __sin(y[0], y[1], 1);
+ c = __cos(y[0], y[1]);
+ switch (n&3) {
+ case 0:
+ *sin = s;
+ *cos = c;
+ break;
+ case 1:
+ *sin = c;
+ *cos = -s;
+ break;
+ case 2:
+ *sin = -s;
+ *cos = -c;
+ break;
+ case 3:
+ default:
+ *sin = -c;
+ *cos = s;
+ break;
+ }
+}