1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
/*========================== begin_copyright_notice ============================
Copyright (C) 2020-2022 Intel Corporation
SPDX-License-Identifier: MIT
============================= end_copyright_notice ===========================*/
#include "../imf.h"
#pragma OPENCL FP_CONTRACT OFF
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_two32 = {0x4f800000u};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c10 = {0xbd8770dcu};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c9 = {0x3e1c5827u};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c8 = {0xbe434bdeu};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c7 = {0x3e55e9b0u};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c6 = {0xbe75d6cau};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c5 = {0x3e93a7cbu};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c4 = {0xbeb8aabcu};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c3 = {0x3ef6389fu};
static __constant union {
unsigned int w;
float f;
} __slog2_ha_nolut_c2h = {0xbf38aa3bu};
static __constant union {
unsigned long w;
unsigned int w32[2];
int s32[2];
double f;
} __slog2_ha_nolut_dc1 = {0x3ff715476395bd86uL};
__attribute__((always_inline))
static inline int __ocl_svml_internal_slog2_ha_nolut(float *a, float *r)
{
float xin = *a;
union {
unsigned int w;
float f;
} x, mant, res;
int iexpon;
unsigned int xa;
float R, poly;
double dR, dpoly, expon;
int nRet = 0;
x.f = xin;
// normalize mantissa to [0.75, 1.5)
// normalized, unbiased exponent
iexpon = (x.w - 0x3f400000u) & 0xff800000u;
// normalized mantissa
mant.w = x.w - iexpon;
// exponent
iexpon >>= 23;
// filter out denormals/zero/negative/Inf/NaN
if ((unsigned int)(x.w - 0x00800000) >= 0x7f000000u)
goto LOG2F_SPECIAL;
LOG2F_MAIN:
// reduced argument
R = mant.f - 1.0f;
expon = (double)iexpon;
// polynomial
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(__slog2_ha_nolut_c10.f, R,
__slog2_ha_nolut_c9.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c8.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c7.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c6.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c5.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c4.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c3.f);
poly = SPIRV_OCL_BUILTIN(fma, _f32_f32_f32, )(poly, R, __slog2_ha_nolut_c2h.f);
dR = (double)R;
dpoly = (double)poly;
dpoly = SPIRV_OCL_BUILTIN(fma, _f64_f64_f64, )(dpoly, dR, __slog2_ha_nolut_dc1.f);
dpoly = SPIRV_OCL_BUILTIN(fma, _f64_f64_f64, )(dpoly, dR, expon);
poly = (float)dpoly;
*r = poly;
return nRet;
LOG2F_SPECIAL:
xa = x.w & 0x7fffffffu;
// zero
if (!xa) {
nRet = 2;
res.w = 0xff800000u;
*r = res.f;
return nRet;
}
// Inf/NaN or negative?
if (x.w >= 0x7f800000u) {
// +Inf?
if (x.w == 0x7f800000u) {
*r = x.f;
return nRet;
}
// return QNaN
nRet = 1;
x.w |= 0x7fc00000u;
*r = x.f;
return nRet;
}
// positive denormal?
if (!(xa & 0x7f800000)) {
// scale x by 2^32
x.f *= __slog2_ha_nolut_two32.f;
// normalized, unbiased exponent
iexpon = (x.w - 0x3f400000u) & 0xff800000u;
// normalized mantissa
mant.w = x.w - iexpon;
// exponent
iexpon >>= 23;
iexpon -= 32;
}
goto LOG2F_MAIN;
}
float __ocl_svml_log2f_ha_noLUT(float x)
{
float r;
__ocl_svml_internal_slog2_ha_nolut(&x, &r);
return r;
}
|
