text: // Copyright (c) Facebook, Inc. and its affiliates.
  // All rights reserved.
  //
  // Copyright 2019 Google LLC
  //
  // This source code is licensed under the BSD-style license found in the
  // LICENSE file in the root directory of this source tree.
  
  #pragma once
  
  #include <gtest/gtest.h>
  
  #include <algorithm>
  #include <cassert>
  #include <cstddef>
  #include <cstdlib>
  #include <functional>
  #include <limits>
  #include <random>
  #include <vector>
  
  #include <xnnpack.h>
  #include <xnnpack/params-init.h>
  #include <xnnpack/params.h>
  #include <xnnpack/requantization.h>
  
  
  class VAddMicrokernelTester {
   public:
    enum class Variant {
      Native,
      Scalar,
    };
  
    inline VAddMicrokernelTester& n(size_t n) {
      assert(n != 0);
      this->n_ = n;
      return *this;
    }
  
    inline size_t n() const {
      return this->n_;
    }
  
    inline VAddMicrokernelTester& inplace_a(bool inplace_a) {
      this->inplace_a_ = inplace_a;
      return *this;
    }
  
    inline bool inplace_a() const {
      return this->inplace_a_;
    }
  
    inline VAddMicrokernelTester& inplace_b(bool inplace_b) {
      this->inplace_b_ = inplace_b;
      return *this;
    }
  
    inline bool inplace_b() const {
      return this->inplace_b_;
    }
  
    inline VAddMicrokernelTester& a_scale(float a_scale) {
      assert(a_scale > 0.0f);
      assert(std::isnormal(a_scale));
      this->a_scale_ = a_scale;
      return *this;
    }
  
    inline float a_scale() const {
      return this->a_scale_;
    }
  
    inline VAddMicrokernelTester& a_zero_point(uint8_t a_zero_point) {
      this->a_zero_point_ = a_zero_point;
      return *this;
    }
  
    inline uint8_t a_zero_point() const {
      return this->a_zero_point_;
    }
  
    inline VAddMicrokernelTester& b_scale(float b_scale) {
      assert(b_scale > 0.0f);
      assert(std::isnormal(b_scale));
      this->b_scale_ = b_scale;
      return *this;
    }
  
    inline float b_scale() const {
      return this->b_scale_;
    }
  
    inline VAddMicrokernelTester& b_zero_point(uint8_t b_zero_point) {
      this->b_zero_point_ = b_zero_point;
      return *this;
    }
  
    inline uint8_t b_zero_point() const {
      return this->b_zero_point_;
    }
  
    inline VAddMicrokernelTester& y_scale(float y_scale) {
      assert(y_scale > 0.0f);
      assert(std::isnormal(y_scale));
      this->y_scale_ = y_scale;
      return *this;
    }
  
    inline float y_scale() const {
      return this->y_scale_;
    }
  
    inline VAddMicrokernelTester& y_zero_point(uint8_t y_zero_point) {
      this->y_zero_point_ = y_zero_point;
      return *this;
    }
  
    inline uint8_t y_zero_point() const {
      return this->y_zero_point_;
    }
  
    inline VAddMicrokernelTester& qmin(uint8_t qmin) {
      this->qmin_ = qmin;
      return *this;
    }
  
    inline uint8_t qmin() const {
      return this->qmin_;
    }
  
    inline VAddMicrokernelTester& qmax(uint8_t qmax) {
      this->qmax_ = qmax;
      return *this;
    }
  
    inline uint8_t qmax() const {
      return this->qmax_;
    }
  
    inline VAddMicrokernelTester& iterations(size_t iterations) {
      this->iterations_ = iterations;
      return *this;
    }
  
    inline size_t iterations() const {
      return this->iterations_;
    }
  
    void Test(xnn_qu8_vadd_minmax_ukernel_function vadd_minmax, Variant variant = Variant::Native) const {
      std::random_device random_device;
      auto rng = std::mt19937(random_device());
      auto u8rng = std::bind(std::uniform_int_distribution<uint32_t>(0, std::numeric_limits<uint8_t>::max()), rng);
  
      std::vector<uint8_t> a(n() + XNN_EXTRA_BYTES / sizeof(uint8_t));
      std::vector<uint8_t> b(n() + XNN_EXTRA_BYTES / sizeof(uint8_t));
      std::vector<uint8_t> y(n() + (inplace_a() || inplace_b() ? XNN_EXTRA_BYTES / sizeof(uint8_t) : 0));
      std::vector<float> y_fp(n());
      std::vector<uint8_t> y_ref(n());
      for (size_t iteration = 0; iteration < iterations(); iteration++) {
        std::generate(a.begin(), a.end(), std::ref(u8rng));
        std::generate(b.begin(), b.end(), std::ref(u8rng));
        if (inplace_a() || inplace_b()) {
          std::generate(y.begin(), y.end(), std::ref(u8rng));
        } else {
          std::fill(y.begin(), y.end(), 0xA5);
        }
        const uint8_t* a_data = inplace_a() ? y.data() : a.data();
        const uint8_t* b_data = inplace_b() ? y.data() : b.data();
  
        // Prepare parameters.
        xnn_qu8_add_params quantization_params = { };
        switch (variant) {
          case Variant::Native:
            quantization_params = xnn_init_qu8_add_params(
              a_zero_point(), b_zero_point(), y_zero_point(),
              a_scale() / y_scale(), b_scale() / y_scale(),
              qmin(), qmax());
            break;
          case Variant::Scalar:
            quantization_params = xnn_init_scalar_qu8_add_params(
              a_zero_point(), b_zero_point(), y_zero_point(),
              a_scale() / y_scale(), b_scale() / y_scale(),
              qmin(), qmax());
            break;
        }
        const xnn_qu8_add_params scalar_quantization_params =
            xnn_init_scalar_qu8_add_params(
              a_zero_point(), b_zero_point(), y_zero_point(),
              a_scale() / y_scale(), b_scale() / y_scale(),
              qmin(), qmax());
  
        // Compute reference results.
        for (size_t i = 0; i < n(); i++) {
          y_fp[i] = float(y_zero_point()) +
            float(int32_t(a_data[i]) - int32_t(a_zero_point())) * (a_scale() / y_scale()) +
            float(int32_t(b_data[i]) - int32_t(b_zero_point())) * (b_scale() / y_scale());
          y_fp[i] = std::min<float>(y_fp[i], float(qmax()));
          y_fp[i] = std::max<float>(y_fp[i], float(qmin()));
          y_ref[i] = xnn_add_quantize(a_data[i], b_data[i], scalar_quantization_params);
        }
  
        // Call optimized micro-kernel.
        vadd_minmax(n(), a_data, b_data, y.data(), &quantization_params);
  
        // Verify results.
        for (size_t i = 0; i < n(); i++) {
          ASSERT_LE(uint32_t(y[i]), uint32_t(qmax()))
            << "at " << i << ", n = " << n();
          ASSERT_GE(uint32_t(y[i]), uint32_t(qmin()))
            << "at " << i << ", n = " << n();
          ASSERT_NEAR(float(int32_t(y[i])), y_fp[i], 0.6f)
            << "at " << i << ", n = " << n();
          ASSERT_EQ(uint32_t(y_ref[i]), uint32_t(y[i]))
            << "at " << i << ", n = " << n();
        }
      }
    }
  
   private:
    size_t n_{1};
    bool inplace_a_{false};
    bool inplace_b_{false};
    float a_scale_{0.75f};
    float b_scale_{1.25f};
    float y_scale_{0.96875f};
    uint8_t a_zero_point_{121};
    uint8_t b_zero_point_{127};
    uint8_t y_zero_point_{133};
    uint8_t qmin_{0};
    uint8_t qmax_{255};
    size_t iterations_{15};
  };
  