1/*
2 * Copyright (c) 2014 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20 * THE SOFTWARE.
21 */
22#include <clc/clc.h>
23
24#include "math.h"
25#include "sincos_helpers.h"
26#include "../clcmacro.h"
27#include "tables.h"
28
29_CLC_DEF _CLC_OVERLOAD float __clc_tanpi(float x)
30{
31    int ix = as_int(x);
32    int xsgn = ix & 0x80000000;
33    int xnsgn = xsgn ^ 0x80000000;
34    ix ^= xsgn;
35    float ax = as_float(ix);
36    int iax = (int)ax;
37    float r = ax - iax;
38    int xodd = xsgn ^ (iax & 0x1 ? 0x80000000 : 0);
39
40    // Initialize with return for +-Inf and NaN
41    int ir = 0x7fc00000;
42
43    // 2^24 <= |x| < Inf, the result is always even integer
44    ir = ix < 0x7f800000 ? xsgn : ir;
45
46    // 2^23 <= |x| < 2^24, the result is always integer
47    ir = ix < 0x4b800000 ? xodd : ir;
48
49    // 0x1.0p-7 <= |x| < 2^23, result depends on which 0.25 interval
50
51    // r < 1.0
52    float a = 1.0f - r;
53    int e = 0;
54    int s = xnsgn;
55
56    // r <= 0.75
57    int c = r <= 0.75f;
58    a = c ? r - 0.5f : a;
59    e = c ? 1 : e;
60    s = c ? xsgn : s;
61
62    // r < 0.5
63    c = r < 0.5f;
64    a = c ? 0.5f - r : a;
65    s = c ? xnsgn : s;
66
67    // 0 < r <= 0.25
68    c = r <= 0.25f;
69    a = c ? r : a;
70    e = c ? 0 : e;
71    s = c ? xsgn : s;
72
73    float t = __clc_tanf_piby4(a * M_PI_F, 0);
74    float tr = -native_recip(t);
75    int jr = s ^ as_int(e ? tr : t);
76
77    jr = r == 0.5f ? xodd | 0x7f800000 : jr;
78
79    ir = ix < 0x4b000000 ? jr : ir;
80
81    return as_float(ir);
82}
83_CLC_UNARY_VECTORIZE(_CLC_DEF _CLC_OVERLOAD, float, __clc_tanpi, float);
84
85#ifdef cl_khr_fp64
86#include "sincosD_piby4.h"
87
88_CLC_DEF _CLC_OVERLOAD double __clc_tanpi(double x)
89{
90    long ix = as_long(x);
91    long xsgn = ix & 0x8000000000000000L;
92    long xnsgn = xsgn ^ 0x8000000000000000L;
93    ix ^= xsgn;
94    double ax = as_double(ix);
95    long iax = (long)ax;
96    double r = ax - iax;
97    long xodd = xsgn ^ (iax & 0x1 ? 0x8000000000000000L : 0L);
98
99    // Initialize with return for +-Inf and NaN
100    long ir = 0x7ff8000000000000L;
101
102    // 2^53 <= |x| < Inf, the result is always even integer
103    ir = ix < 0x7ff0000000000000L ? xsgn : ir;
104
105    // 2^52 <= |x| < 2^53, the result is always integer
106    ir = ix < 0x4340000000000000L ? xodd : ir;
107
108    // 0x1.0p-14 <= |x| < 2^53, result depends on which 0.25 interval
109
110    // r < 1.0
111    double a = 1.0 - r;
112    int e = 0;
113    long s = xnsgn;
114
115    // r <= 0.75
116    int c = r <= 0.75;
117    double t = r - 0.5;
118    a = c ? t : a;
119    e = c ? 1 : e;
120    s = c ? xsgn : s;
121
122    // r < 0.5
123    c = r < 0.5;
124    t = 0.5 - r;
125    a = c ? t : a;
126    s = c ? xnsgn : s;
127
128    // r <= 0.25
129    c = r <= 0.25;
130    a = c ? r : a;
131    e = c ? 0 : e;
132    s = c ? xsgn : s;
133
134    double api = a * M_PI;
135    double2 tt = __clc_tan_piby4(api, 0.0);
136    long jr = s ^ as_long(e ? tt.hi : tt.lo);
137
138    long si = xodd | 0x7ff0000000000000L;
139    jr = r == 0.5 ? si : jr;
140
141    ir = ix < 0x4330000000000000L ? jr : ir;
142
143    return as_double(ir);
144}
145_CLC_UNARY_VECTORIZE(_CLC_DEF _CLC_OVERLOAD, double, __clc_tanpi, double);
146#endif
147