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+/* sinq.c -- __float128 version of s_sin.c.
+ * Conversion to long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* sinq(x)
+ * Return sine function of x.
+ *
+ * kernel function:
+ * __quadmath_kernel_sinq ... sine function on [-pi/4,pi/4]
+ * __quadmath_kernel_cosq ... cose function on [-pi/4,pi/4]
+ * __quadmath_rem_pio2q ... argument reduction routine
+ *
+ * Method.
+ * Let S,C and T denote the sin, cos and tan respectively on
+ * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ * in [-pi/4 , +pi/4], and let n = k mod 4.
+ * We have
+ *
+ * n sin(x) cos(x) tan(x)
+ * ----------------------------------------------------------
+ * 0 S C T
+ * 1 C -S -1/T
+ * 2 -S -C T
+ * 3 -C S -1/T
+ * ----------------------------------------------------------
+ *
+ * Special cases:
+ * Let trig be any of sin, cos, or tan.
+ * trig(+-INF) is NaN, with signals;
+ * trig(NaN) is that NaN;
+ *
+ * Accuracy:
+ * TRIG(x) returns trig(x) nearly rounded
+ */
+
+#include "quadmath-imp.h"
+
+__float128
+sinq (__float128 x)
+{
+ __float128 y[2],z=0.0Q;
+ int64_t n, ix;
+
+ /* High word of x. */
+ GET_FLT128_MSW64(ix,x);
+
+ /* |x| ~< pi/4 */
+ ix &= 0x7fffffffffffffffLL;
+ if(ix <= 0x3ffe921fb54442d1LL)
+ return __quadmath_kernel_sinq(x,z,0);
+
+ /* sin(Inf or NaN) is NaN */
+ else if (ix>=0x7fff000000000000LL) {
+ if (ix == 0x7fff000000000000LL) {
+ GET_FLT128_LSW64(n,x);
+ }
+ return x-x;
+ }
+
+ /* argument reduction needed */
+ else {
+ n = __quadmath_rem_pio2q(x,y);
+ switch(n&3) {
+ case 0: return __quadmath_kernel_sinq(y[0],y[1],1);
+ case 1: return __quadmath_kernel_cosq(y[0],y[1]);
+ case 2: return -__quadmath_kernel_sinq(y[0],y[1],1);
+ default:
+ return -__quadmath_kernel_cosq(y[0],y[1]);
+ }
+ }
+}