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1 /*
2  * Single-precision sin/cos function.
3  *
4  * Copyright (c) 2018, Arm Limited.
5  * SPDX-License-Identifier: MIT
6  */
7 
8 #if WANT_SINGLEPREC
9 #include "single/s_sincosf.c"
10 #else
11 
12 #include <stdint.h>
13 #include <math.h>
14 #include "math_config.h"
15 #include "sincosf.h"
16 
17 /* Fast sincosf implementation.  Worst-case ULP is 0.5607, maximum relative
18    error is 0.5303 * 2^-23.  A single-step range reduction is used for
19    small values.  Large inputs have their range reduced using fast integer
20    arithmetic.  */
21 void
sincosf(float y,float * sinp,float * cosp)22 sincosf (float y, float *sinp, float *cosp)
23 {
24   double x = y;
25   double s;
26   int n;
27   const sincos_t *p = &__sincosf_table[0];
28 
29   if (abstop12 (y) < abstop12 (pio4))
30     {
31       double x2 = x * x;
32 
33       if (unlikely (abstop12 (y) < abstop12 (0x1p-12f)))
34 	{
35 	  if (unlikely (abstop12 (y) < abstop12 (0x1p-126f)))
36 	    /* Force underflow for tiny y.  */
37 	    force_eval_float (x2);
38 	  *sinp = y;
39 	  *cosp = 1.0f;
40 	  return;
41 	}
42 
43       sincosf_poly (x, x2, p, 0, sinp, cosp);
44     }
45   else if (abstop12 (y) < abstop12 (120.0f))
46     {
47       x = reduce_fast (x, p, &n);
48 
49       /* Setup the signs for sin and cos.  */
50       s = p->sign[n & 3];
51 
52       if (n & 2)
53 	p = &__sincosf_table[1];
54 
55       sincosf_poly (x * s, x * x, p, n, sinp, cosp);
56     }
57   else if (likely (abstop12 (y) < abstop12 (INFINITY)))
58     {
59       uint32_t xi = asuint (y);
60       int sign = xi >> 31;
61 
62       x = reduce_large (xi, &n);
63 
64       /* Setup signs for sin and cos - include original sign.  */
65       s = p->sign[(n + sign) & 3];
66 
67       if ((n + sign) & 2)
68 	p = &__sincosf_table[1];
69 
70       sincosf_poly (x * s, x * x, p, n, sinp, cosp);
71     }
72   else
73     {
74       /* Return NaN if Inf or NaN for both sin and cos.  */
75       *sinp = *cosp = y - y;
76 #if WANT_ERRNO
77       /* Needed to set errno for +-Inf, the add is a hack to work
78 	 around a gcc register allocation issue: just passing y
79 	 affects code generation in the fast path.  */
80       __math_invalidf (y + y);
81 #endif
82     }
83 }
84 
85 #endif
86