freertos: release the generic version source code

freertos runs on the second core (small one) of the CPU

freertos/cvitek/common/include/cv1835/arm_optimized-routines/sincosf.h

@@ -0,0 +1,153 @@
+/*
+ * Header for sinf, cosf and sincosf.
+ *
+ * Copyright (c) 2018, Arm Limited.
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <stdint.h>
+#include <math.h>
+#include "math_config.h"
+
+/* 2PI * 2^-64.  */
+static const double pi63 = 0x1.921FB54442D18p-62;
+/* PI / 4.  */
+static const double pio4 = 0x1.921FB54442D18p-1;
+
+/* 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.  */
+  double c0, c1, c2, c3, c4;	/* Cosine polynomial.  */
+  double s1, s2, s3;		/* Sine polynomial.  */
+} sincos_t;
+
+/* Polynomial data (the cosine polynomial is negated in the 2nd entry).  */
+extern const sincos_t __sincosf_table[2] HIDDEN;
+
+/* Table with 4/PI to 192 bit precision.  */
+extern const uint32_t __inv_pio4[] HIDDEN;
+
+/* Top 12 bits of the float representation with the sign bit cleared.  */
+static inline uint32_t
+abstop12 (float x)
+{
+  return (asuint (x) >> 20) & 0x7ff;
+}
+
+/* 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)
+{
+  double x3, x4, x5, x6, s, c, c1, c2, s1;
+
+  x4 = x2 * x2;
+  x3 = x2 * x;
+  c2 = p->c3 + x2 * p->c4;
+  s1 = p->s2 + x2 * p->s3;
+
+  /* Swap sin/cos result based on quadrant.  */
+  float *tmp = (n & 1 ? cosp : sinp);
+  cosp = (n & 1 ? sinp : cosp);
+  sinp = tmp;
+
+  c1 = p->c0 + x2 * p->c1;
+  x5 = x3 * x2;
+  x6 = x4 * x2;
+
+  s = x + x3 * p->s1;
+  c = c1 + x4 * p->c2;
+
+  *sinp = s + x5 * s1;
+  *cosp = c + x6 * c2;
+}
+
+/* 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->s2 + x2 * p->s3;
+
+      x7 = x3 * x2;
+      s = x + x3 * p->s1;
+
+      return s + x7 * s1;
+    }
+  else
+    {
+      x4 = x2 * x2;
+      c2 = p->c3 + x2 * p->c4;
+      c1 = p->c0 + x2 * p->c1;
+
+      x6 = x4 * x2;
+      c = c1 + x4 * p->c2;
+
+      return c + x6 * c2;
+    }
+}
+
+/* Fast range reduction using single multiply-subtract.  Return the modulo of
+   X as a value between -PI/4 and PI/4 and store the quadrant in NP.
+   The values for PI/2 and 2/PI are accessed via P.  Since PI/2 as a double
+   is accurate to 55 bits and the worst-case cancellation happens at 6 * PI/4,
+   the result is accurate for |X| <= 120.0.  */
+static inline double
+reduce_fast (double x, const sincos_t *p, int *np)
+{
+  double r;
+#if TOINT_INTRINSICS
+  /* Use fast round and lround instructions when available.  */
+  r = x * p->hpi_inv;
+  *np = converttoint (r);
+  return x - roundtoint (r) * p->hpi;
+#else
+  /* Use scaled float to int conversion with explicit rounding.
+     hpi_inv is prescaled by 2^24 so the quadrant ends up in bits 24..31.
+     This avoids inaccuracies introduced by truncating negative values.  */
+  r = x * p->hpi_inv;
+  int n = ((int32_t)r + 0x800000) >> 24;
+  *np = n;
+  return x - n * p->hpi;
+#endif
+}
+
+/* Reduce the range of XI to a multiple of PI/2 using fast integer arithmetic.
+   XI is a reinterpreted float and must be >= 2.0f (the sign bit is ignored).
+   Return the modulo between -PI/4 and PI/4 and store the quadrant in NP.
+   Reduction uses a table of 4/PI with 192 bits of precision.  A 32x96->128 bit
+   multiply computes the exact 2.62-bit fixed-point modulo.  Since the result
+   can have at most 29 leading zeros after the binary point, the double
+   precision result is accurate to 33 bits.  */
+static inline double
+reduce_large (uint32_t xi, int *np)
+{
+  const uint32_t *arr = &__inv_pio4[(xi >> 26) & 15];
+  int shift = (xi >> 23) & 7;
+  uint64_t n, res0, res1, res2;
+
+  xi = (xi & 0xffffff) | 0x800000;
+  xi <<= shift;
+
+  res0 = xi * arr[0];
+  res1 = (uint64_t)xi * arr[4];
+  res2 = (uint64_t)xi * arr[8];
+  res0 = (res2 >> 32) | (res0 << 32);
+  res0 += res1;
+
+  n = (res0 + (1ULL << 61)) >> 62;
+  res0 -= n << 62;
+  double x = (int64_t)res0;
+  *np = n;
+  return x * pi63;
+}