xref: /aosp_15_r20/external/tensorflow/tensorflow/compiler/mlir/lite/quantization/numerical_utils.h (revision b6fb3261f9314811a0f4371741dbb8839866f948)
1 /* Copyright 2020 The TensorFlow Authors. All Rights Reserved.
2 
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6 
7     http://www.apache.org/licenses/LICENSE-2.0
8 
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15 
16 #ifndef TENSORFLOW_COMPILER_MLIR_LITE_QUANTIZATION_NUMERICAL_UTILS_H_
17 #define TENSORFLOW_COMPILER_MLIR_LITE_QUANTIZATION_NUMERICAL_UTILS_H_
18 
19 #include <cstdint>
20 #include <optional>
21 #include <utility>
22 
23 #include "absl/types/optional.h"
24 
25 namespace mlir {
26 namespace quant {
27 
28 using QuantizedMultiplier = std::pair<int32_t, int32_t>;
29 using QuantizedRange = std::pair<int32_t, int32_t>;
30 
31 // Decompose double precision multiplier to integer multiplier and exponent.
32 //    double_multiplier = int_multiplier * 2 ^ (-31 + exponent)
33 // int_multiplier will be range of (2^31, 2^30].
34 QuantizedMultiplier QuantizeMultiplier(double double_multiplier);
35 
36 // Calculate the effective quantized value range for the scale, zero point. The
37 // range is the minimum range defined by [rmin, rmax] and [qmin, qmax].
38 QuantizedRange CalculateQuantizedRange(double scale, int32_t zero_point,
39                                        std::optional<double> rmin,
40                                        std::optional<double> rmax, int32_t qmin,
41                                        int32_t qmax);
42 
43 }  // namespace quant
44 }  // namespace mlir
45 
46 #endif  // TENSORFLOW_COMPILER_MLIR_LITE_QUANTIZATION_NUMERICAL_UTILS_H_
47