Tracy Narine | 10403ec | 2023-11-28 11:55:08 +0000 | [diff] [blame] | 1 | // |
| 2 | // Copyright © 2024 Arm Ltd and Contributors. All rights reserved. |
| 3 | // SPDX-License-Identifier: MIT |
| 4 | // |
| 5 | |
| 6 | #include <armnn/Exceptions.hpp> |
| 7 | |
| 8 | #pragma once |
| 9 | |
| 10 | inline void CreateRescaleTosaOperator(const std::string& inputName, |
| 11 | const std::string& outputName, |
| 12 | DType output_type, |
| 13 | const std::vector<int32_t>& shape, |
| 14 | int32_t scale_multiplier, |
| 15 | int32_t scale_shift, |
| 16 | int32_t input_zp, |
| 17 | int32_t output_zp, |
| 18 | bool double_round, |
| 19 | bool scale32, |
| 20 | TosaSerializationOperator** op, |
| 21 | TosaSerializationTensor** tensor) |
| 22 | { |
| 23 | if (!op) |
| 24 | { |
| 25 | throw armnn::Exception("CreateRescaleTosaOperator: nullptr op"); |
| 26 | } |
| 27 | |
| 28 | std::vector<int32_t> multipliers{scale_multiplier}; |
| 29 | std::vector<int32_t> shifts{scale_shift}; |
| 30 | TosaRescaleAttribute attribute(input_zp, |
| 31 | output_zp, |
| 32 | multipliers, |
| 33 | shifts, |
| 34 | scale32, |
| 35 | double_round, |
| 36 | false); |
| 37 | |
| 38 | // op |
| 39 | *op = new TosaSerializationOperator(Op_RESCALE, Attribute_RescaleAttribute, &attribute, {inputName}, {outputName}); |
| 40 | if (!(*op)) |
| 41 | { |
| 42 | throw armnn::Exception("CreateRescaleTosaOperator: failed to created operator"); |
| 43 | } |
| 44 | if (tensor != nullptr) |
| 45 | { |
| 46 | // tensor |
| 47 | *tensor = new TosaSerializationTensor(outputName, shape, output_type, {}); |
| 48 | if (! (*tensor)) |
| 49 | { |
| 50 | throw armnn::Exception("CreateRescaleTosaOperator: failed to created tensor"); |
| 51 | } |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | inline void CreateRescaleTosaOperator(const std::string& inputName, |
| 56 | const std::string& outputName, |
| 57 | DType output_type, |
| 58 | const std::vector<int32_t>& shape, |
| 59 | double scale, |
| 60 | int32_t input_zp, |
| 61 | int32_t output_zp, |
| 62 | bool double_round, |
| 63 | bool scale32, |
| 64 | TosaSerializationOperator** op, |
| 65 | TosaSerializationTensor** tensor) |
| 66 | { |
| 67 | // The code that follows is based on the behaviour specified in |
| 68 | // https://www.mlplatform.org/tosa/tosa_spec.html#_precision_scaling |
| 69 | |
| 70 | auto GetScaleParams = [](double scale, double& m, int32_t& n) |
| 71 | { |
| 72 | m = 0; |
| 73 | n = 0; |
| 74 | |
| 75 | double lastErr = 1e06; |
| 76 | |
| 77 | const int32_t numExponents = 62; |
| 78 | const double start = 1.0; |
| 79 | const double end = 2.0; |
| 80 | |
| 81 | // Slow iterative approach but running in Reference only |
| 82 | for (int32_t i = 0; i < numExponents; ++i) |
| 83 | { |
| 84 | double exp = 1.0 / (1 << i); |
| 85 | double currentM = scale / exp; // Find current m given value = currentM * exp |
| 86 | if ((currentM >= start) && (currentM < end)) |
| 87 | { |
| 88 | double value = currentM * exp; |
| 89 | double err = std::abs(scale - value); |
| 90 | if (err < lastErr) |
| 91 | { |
| 92 | // Take the m, n that minimize the error |
| 93 | n = i; |
| 94 | m = currentM; |
| 95 | lastErr = err; |
| 96 | } |
| 97 | } |
| 98 | } |
| 99 | }; |
| 100 | |
| 101 | auto GetMultiplierShiftByScale = [GetScaleParams](bool scale32, double scale, int32_t& multiplier, int32_t& shift) |
| 102 | { |
| 103 | double m = 0; |
| 104 | int32_t n = 0; |
| 105 | |
| 106 | GetScaleParams(scale, m, n); |
| 107 | |
| 108 | multiplier = (scale32) ? (1 << 30) * static_cast<int32_t>(m) : (1 << 14) * static_cast<int32_t>(m); |
| 109 | shift = (scale32) ? (30 + n) : (14 + n); |
| 110 | }; |
| 111 | |
| 112 | int32_t multiplier; |
| 113 | int32_t shift; |
| 114 | GetMultiplierShiftByScale(scale32, scale, multiplier, shift); |
| 115 | CreateRescaleTosaOperator(inputName, outputName, output_type, shape, multiplier, shift, |
| 116 | input_zp, output_zp, double_round, scale32, op, tensor); |
| 117 | } |
| 118 | |
| 119 | inline void CreateFromInt32RescaleTosaOperator(const std::string& inputName, |
| 120 | const std::string& outputName, |
| 121 | DType output_type, |
| 122 | const std::vector<int32_t>& shape, |
| 123 | double output_scale, |
| 124 | int32_t output_zp, |
| 125 | TosaSerializationOperator** op, |
| 126 | TosaSerializationTensor** tensor) |
| 127 | { |
| 128 | CreateRescaleTosaOperator(inputName, outputName, output_type, shape, |
| 129 | output_scale, 0, output_zp, true, true, op, tensor); |
| 130 | } |