xref: /aosp_15_r20/external/ComputeLibrary/tests/validation/reference/UtilsQuantizedAsymm.h (revision c217d954acce2dbc11938adb493fc0abd69584f3)
1 /*
2  * Copyright (c) 2017-2021 Arm Limited.
3  *
4  * SPDX-License-Identifier: MIT
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in all
14  * copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22  * SOFTWARE.
23  */
24 #ifndef ARM_COMPUTE_TEST_VALIDATION_UTILS_QUANTIZED_ASYMM_H
25 #define ARM_COMPUTE_TEST_VALIDATION_UTILS_QUANTIZED_ASYMM_H
26 
27 #include <cstdint>
28 
29 namespace arm_compute
30 {
31 namespace test
32 {
33 namespace validation
34 {
35 namespace
36 {
37 #if __clang__
38 // This has been tested on clang 7.0.2 (__clang_major__ == 7 && __clang_minor__ == 0 && __clang_patchlevel__ == 2)
to_int64(int32_t val)39 inline int64_t to_int64(int32_t val)
40 {
41     return static_cast<int64_t>(val) | ((val < 0) ? (((1ll << 32) - 1) << 32) : 0);
42 }
43 #else  // __clang__
44 inline int64_t to_int64(int32_t val)
45 {
46     return static_cast<int64_t>(val);
47 }
48 #endif // __clang__
49 } // namespace
50 
51 /** Rounded to nearest division by a power-of-two. */
asymm_rounding_divide_by_pow2(int32_t x,int exponent)52 inline int32_t asymm_rounding_divide_by_pow2(int32_t x, int exponent)
53 {
54     const int32_t mask      = (1 << exponent) - 1;
55     const int32_t threshold = (mask >> 1) + (x < 0 ? 1 : 0);
56     return (x >> exponent) + ((x & mask) > threshold ? 1 : 0);
57 }
58 
59 /** Multiplication of two integers. The same as ARMv7 Arm® Neon™ VQRDMULH instruction. */
asymm_int_mult(int32_t a,int32_t b)60 inline int32_t asymm_int_mult(int32_t a, int32_t b)
61 {
62     const bool    overflow     = a == b && a == std::numeric_limits<int32_t>::min();
63     const int64_t a_64         = to_int64(a);
64     const int64_t b_64         = to_int64(b);
65     const int64_t ab_64        = a_64 * b_64;
66     const int32_t nudge        = ab_64 >= 0 ? (1 << 30) : (1 - (1 << 30));
67     const int32_t ab_x2_high32 = static_cast<int32_t>((ab_64 + nudge) / (1ll << 31));
68     return overflow ? std::numeric_limits<int32_t>::max() : ab_x2_high32;
69 }
70 
71 /** Quantize down the input value in range [min, max]. */
quantize_down_scale_by_fixedpoint(int32_t val,int32_t result_mult_int,int32_t result_shift,int32_t result_offset_after_shift,int32_t min,int32_t max)72 inline int32_t quantize_down_scale_by_fixedpoint(int32_t val, int32_t result_mult_int, int32_t result_shift,
73                                                  int32_t result_offset_after_shift, int32_t min, int32_t max)
74 {
75     int32_t res = 0;
76     if(result_shift < 0)
77     {
78         res = asymm_int_mult(val * (1 << (-result_shift)), result_mult_int);
79     }
80     else
81     {
82         res = asymm_rounding_divide_by_pow2(asymm_int_mult(val, result_mult_int), result_shift);
83     }
84     res += result_offset_after_shift;
85     res = utility::clamp<int32_t>(res, min, max);
86     return res;
87 }
88 } // namespace validation
89 } // namespace test
90 } // namespace arm_compute
91 #endif /* ARM_COMPUTE_TEST_VALIDATION_UTILS_QUANTIZED_ASYMM_H */
92