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 // SPDX-License-Identifier: MIT
 // Copyright (c) 2018-2023, Advanced Micro Devices, Inc. All rights reserved.
  
 #pragma once
  
 #include "ck_tile/core/config.hpp"
 #include "ck_tile/core/numeric/half.hpp"
 #include <stdint.h>
 #include <tuple>
 #include <type_traits>
  
 namespace ck_tile {
  
 // return 0 if data is not fp16 or fp32
 template <typename T, uint32_t seed_>
 struct prand_generator_t
 {
     CK_TILE_HOST_DEVICE uint32_t operator()(int, T, uint32_t = seed_) { return 0; }
 };
  
 // version for fp32
 template <uint32_t seed_>
 struct prand_generator_t<float, seed_>
 {
     CK_TILE_HOST_DEVICE uint32_t operator()(int id, float val, uint32_t seed = seed_)
     {
         uint32_t x         = bit_cast<uint32_t>(val);
         uint32_t drop_bits = uint32_t(x) & 0xFFFFu;
         drop_bits ^= x >> 16;
         drop_bits = ((drop_bits & 31) << 11) | (drop_bits >> 5);
         drop_bits *= 0x7000149;
         // NOTE: If id is in 64 bit, we are only using lower 32 bit.
         //       So, it can have an effect of using same id for multiple elements when the id is
         //       very large!
         uint32_t rng = (drop_bits ^ 0x13371337 ^ (id * 229791) ^ seed);
         return rng;
     }
 };
  
 // version for fp16
 template <uint32_t seed_>
 struct prand_generator_t<half_t, seed_>
 {
     CK_TILE_HOST_DEVICE uint32_t operator()(int id, half_t val, uint32_t seed = seed_)
     {
         uint16_t x         = bit_cast<uint16_t>(val);
         uint32_t drop_bits = uint32_t(x) & 0xFFFFu;
         drop_bits          = ((drop_bits & 31) << 11) | (drop_bits >> 5);
         drop_bits *= 0x7000149;
         // NOTE: If id is in 64 bit, we are only using lower 32 bit.
         //       So, it can have an effect of using same id for multiple elements when the id is
         //       very large!
         uint32_t rng = (drop_bits ^ 0x13371337 ^ (id * 229791) ^ seed);
         return rng;
     }
 };
  
 } // namespace ck_tile