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+/* Used by sinf, cosf and sincosf functions.  X86-64 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+typedef double v2df_t __attribute__ ((vector_size (2 * sizeof (double))));
+
+#ifdef __SSE2_MATH__
+typedef float v4sf_t __attribute__ ((vector_size (4 * sizeof (float))));
+
+static inline void
+v2df_to_sf (v2df_t v2df, float *f0p, float *f1p)
+{
+  v4sf_t v4sf = __builtin_ia32_cvtpd2ps (v2df);
+  *f0p = v4sf[0];
+  *f1p = v4sf[1];
+}
+#else
+static inline void
+v2df_to_sf (v2df_t v2df, float *f0p, float *f1p)
+{
+  *f0p = (float) v2df[0];
+  *f1p = (float) v2df[1];
+}
+#endif
+
+/* The constants and polynomials for sine and cosine.  */
+typedef struct
+{
+  double sign[4];		/* Sign of sine in quadrants 0..3.  */
+  double hpi_inv;		/* 2 / PI ( * 2^24 if !TOINT_INTRINSICS).  */
+  double hpi;			/* PI / 2.  */
+  /* Cosine polynomial: c0, c1, c2, c3, c4.
+     Sine polynomial: s1, s2, s3.  */
+  double c0, c1;
+  v2df_t s1c2, s2c3, s3c4;
+} sincos_t;
+
+/* Compute the sine and cosine of inputs X and X2 (X squared), using the
+   polynomial P and store the results in SINP and COSP.  N is the quadrant,
+   if odd the cosine and sine polynomials are swapped.  */
+static inline void
+sincosf_poly (double x, double x2, const sincos_t *p, int n, float *sinp,
+	      float *cosp)
+{
+  v2df_t vx2x2 = { x2, x2 };
+  v2df_t vxx2 = { x, x2 };
+  v2df_t vx3x4, vs1c2;
+
+  vx3x4 = vx2x2 * vxx2;
+  vs1c2 = p->s2c3 + vx2x2 * p->s3c4;
+
+  /* Swap sin/cos result based on quadrant.  */
+  if (n & 1)
+    {
+      float *tmp = cosp;
+      cosp = sinp;
+      sinp = tmp;
+    }
+
+  double c1 = p->c0 + x2 * p->c1;
+  v2df_t vxc1 = { x, c1 };
+  v2df_t vx5x6 = vx3x4 * vx2x2;
+
+  v2df_t vsincos = vxc1 + vx3x4 * p->s1c2;
+  vsincos = vsincos + vx5x6 * vs1c2;
+  v2df_to_sf (vsincos, sinp, cosp);
+}
+
+/* Return the sine of inputs X and X2 (X squared) using the polynomial P.
+   N is the quadrant, and if odd the cosine polynomial is used.  */
+static inline float
+sinf_poly (double x, double x2, const sincos_t *p, int n)
+{
+  double x3, x4, x6, x7, s, c, c1, c2, s1;
+
+  if ((n & 1) == 0)
+    {
+      x3 = x * x2;
+      s1 = p->s2c3[0] + x2 * p->s3c4[0];
+
+      x7 = x3 * x2;
+      s = x + x3 * p->s1c2[0];
+
+      return s + x7 * s1;
+    }
+  else
+    {
+      x4 = x2 * x2;
+      c2 = p->s2c3[1] + x2 * p->s3c4[1];
+      c1 = p->c0 + x2 * p->c1;
+
+      x6 = x4 * x2;
+      c = c1 + x4 * p->s1c2[1];
+
+      return c + x6 * c2;
+    }
+}