feat: Implement expt_0802 binary search

Signed-off-by: KunoiSayami <[email protected]>

4 files changed, 316 insertions, 22 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 62d52de..7bc1eac 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -91,10 +91,19 @@ target_link_libraries(expt_0729 m stdc++)
 set_target_properties(expt_0729 PROPERTIES
         CUDA_SEPARABLE_COMPILATION ON)
 set_target_properties(expt_0729 PROPERTIES CUDA_ARCHITECTURES "75")
-set_target_properties(expt_0726 PROPERTIES LINKER_LANGUAGE CUDA)
+set_target_properties(expt_0729 PROPERTIES LINKER_LANGUAGE CUDA)
 
 
 add_executable(expt_0802 expt_0802.cpp)
 #set_target_properties(expt_0729 PROPERTIES LINKER_LANGUAGE CXX)
 target_link_libraries(expt_0802 m stdc++)
 
+
+add_executable(expt_0804 expt_0804.cu)
+#set_target_properties(expt_0804 PROPERTIES LINKER_LANGUAGE CXX)
+target_link_libraries(expt_0804 m stdc++)
+
+set_target_properties(expt_0804 PROPERTIES
+        CUDA_SEPARABLE_COMPILATION ON)
+set_target_properties(expt_0804 PROPERTIES CUDA_ARCHITECTURES "75")
+set_target_properties(expt_0804 PROPERTIES LINKER_LANGUAGE CUDA)
diff --git a/expt_0802.cpp b/expt_0802.cpp
index 32727fb..fbd6c23 100644
--- a/expt_0802.cpp
+++ b/expt_0802.cpp
@@ -4,11 +4,9 @@
 #include <iostream>
 #include <vector>
 
-using namespace std;
-
-vector<vector<int>> a;
-vector<int> result;
-constexpr size_t LENGTH = 2048;
+std::vector<std::vector<int>> a;
+std::vector<int> result;
+constexpr size_t LENGTH = 1024;
 
 void calculate(int l, int r, int dep) {
   if (l > r)
@@ -20,20 +18,48 @@ void calculate(int l, int r, int dep) {
 }
 
 size_t calculate_location(size_t index) {
-  // auto value = result[index + 1];
-  auto real_index = ++index;
-  int step = 0;
-  while (index > 0) {
-    index /= 2;
-    step++;
-  }
-  auto end = (int)std::pow(2, step - 1);
-  auto location = LENGTH / end / 2 * (real_index % end * 2 + 1);
-  if (location == 0) {
-    location = LENGTH;
+  int step = (int)std::log2(++index) + 1;
+  auto location =
+      LENGTH / (1 << step) * ((index & ((1 << (step - 1)) - 1)) * 2 + 1);
+  return location ? location : LENGTH;
+}
+typedef int key_type;
+
+inline double safeStep(double step) { return step < 0 ? 0 : step; }
+
+int get_son_from_step(int point, bool negative) {
+  return negative ? point * 2 : point * 2 + 1;
+}
+
+const key_type *cudaBinarySearch(key_type *const start, const key_type *end,
+                                 const key_type val) {
+  int step_limit = (int)std::log2(LENGTH) + 1;
+  const auto length = (end - start);
+  key_type *last_known_point = start;
+  auto son = 0;
+
+  for (int i = 0; i < step_limit; i++) {
+    const auto next_level_start = start + (1 << (i + 1)) - 1;
+    /*const auto current_time = (1.0 / (1 << (i + 1)));
+    printf("%d ", *level_start);
+    printf("%d %d\n", *last_known_point, (1 << i));
+    if (*last_known_point == val) {
+      puts("find");
+      return last_known_point;
+    }
+    sum = safeStep(sum +
+                   ((*last_known_point > val) ? -current_time : current_time));
+    last_known_point = level_start + (int)(sum * (double)(1 << i));*/
+    if (*last_known_point == val) {
+      puts("found");
+      return last_known_point;
+    }
+    son = get_son_from_step(son, (*last_known_point > val));
+    last_known_point = next_level_start + son;
+    printf("%d\n", *last_known_point);
   }
-  // printf("%d %d %d %lu %lu\n", step, end, value, real_index % end, location);
-  return location;
+  puts("");
+  return last_known_point;
 }
 
 int main() {
@@ -50,10 +76,18 @@ int main() {
       result.push_back(j);
     }
   }
-  cout << endl;
 
-  for (int i = 0; i < LENGTH; i++) {
+  for (int i = 0; i < 32; i++) {
+    printf("%3d ", i);
+  }
+
+  puts("");
+
+  for (int i = 0; i < 32; i++) {
+    printf("%3d ", result[i]);
     assert(calculate_location(i) == result[i]);
   }
+  puts("");
+  cudaBinarySearch(&result[0], &*result.end(), 1024);
   return 0;
 }
diff --git a/expt_0804.cu b/expt_0804.cu
new file mode 100644
index 0000000..47c269e
--- /dev/null
+++ b/expt_0804.cu
@@ -0,0 +1,215 @@
+#include <algorithm>
+#include <cassert>
+#include <cstdio>
+#include <cstring>
+#include <iostream>
+#include <vector>
+
+constexpr size_t length = 2097152;
+std::vector<unsigned long long> population_vector, sample_vector,
+    sample_vector_into_cuda;
+
+unsigned long long max_value = 0, min_value = 0xfffffffff;
+
+inline void store_into_vector(unsigned long long value) {
+  if (max_value < value) {
+    max_value = value;
+  }
+  if (min_value > value) {
+    min_value = value;
+  }
+  population_vector.push_back(value);
+}
+
+typedef unsigned long long key_type;
+
+typedef unsigned long long *key_type_ptr;
+
+constexpr long SAMPLE_LENGTH = 1024;
+
+constexpr long TEST_SIZE = 1024;
+
+__device__ key_type *SampleItem, *PopulationItem;
+__device__ bool *cdf_result;
+__device__ unsigned insert_value;
+#ifdef TEST_BOUNDS
+__device__ unsigned int index_max, index_min;
+#endif
+
+__device__ const key_type *cudaBinarySearch(key_type *start, key_type *end,
+                                            const key_type val) {
+  auto begin = start;
+  key_type *last_known_point = nullptr;
+  while (begin < end) {
+    auto mid = (end - begin) / 2;
+    auto mid_val = *(start + mid);
+    if (val == mid_val) {
+      return start + mid;
+    } else if (val > mid_val) {
+      begin = begin + mid + 1;
+    } else {
+      end = end - mid - 1;
+    }
+    last_known_point = begin;
+  }
+  return last_known_point;
+}
+
+__device__ __host__ size_t calculate_location(size_t index) {
+  int step = (int)std::log2(++index) + 1;
+  auto location =
+      SAMPLE_LENGTH / (1 << step) * ((index & ((1 << (step - 1)) - 1)) * 2 + 1);
+  return location ? location : SAMPLE_LENGTH;
+}
+
+__device__ double sample_cdf(double x) {
+  auto it = cudaBinarySearch(SampleItem, SampleItem + SAMPLE_LENGTH + 2, x);
+  if (it == SampleItem + SAMPLE_LENGTH) {
+    return 1;
+  }
+  if (it == SampleItem) {
+    return 0;
+  }
+  auto it_prev = it - 1;
+  return (double(it_prev - SampleItem) +
+          (x - (double)*it_prev) / (double)(*it - *it_prev)) /
+         double(SAMPLE_LENGTH - 1);
+}
+
+__global__ void initStorage(unsigned scale, unsigned test_size) {
+  cudaFree(cdf_result);
+  cudaMalloc(&cdf_result, scale * test_size * sizeof(bool));
+  memset(cdf_result, 0, scale * test_size * sizeof(bool));
+  insert_value = 0;
+  // printf("initCuda storage\n");
+#ifdef TEST_BOUNDS
+  index_max = 0;
+  index_min = 0x7fffffff;
+#endif
+}
+
+__global__ void initCuda(key_type *sample_item, key_type *population_item) {
+  SampleItem = sample_item;
+  PopulationItem = population_item;
+  // cudaMalloc(&SampleItem, (SAMPLE_LENGTH + 2) * sizeof(unsigned long long));
+  //  cudaMalloc(&Storage, TEST_SIZE * sizeof(key_type));
+  cdf_result = nullptr;
+}
+
+__global__ void kernel(unsigned long step, const double slice_size,
+                       const long split_size) {
+  for (int i = 0; i < step; i++) {
+    auto tid = step * gridDim.x * blockDim.x + blockIdx.x * blockDim.x +
+               threadIdx.x + i;
+
+    // printf("%d\n", tid);
+    auto index = (int)(sample_cdf(PopulationItem[tid]) / slice_size);
+    if (cdf_result[index]) {
+      while (cdf_result[++index]) {
+        assert(index < split_size);
+      }
+    }
+    cdf_result[index] = true;
+    // atomicAdd(&insert_value, 1);
+
+#ifdef TEST_BOUNDS
+    while (true) {
+      unsigned tmp = index_min;
+      if (tmp < tid) {
+        break;
+      }
+      if (atomicCAS(&index_min, tmp, tid) == tmp) {
+        break;
+      }
+    }
+    while (true) {
+      unsigned tmp = index_max;
+      if (tmp > tid) {
+        break;
+      }
+      if (atomicCAS(&index_max, tmp, tid) == tmp) {
+        break;
+      }
+    }
+#endif
+  }
+}
+
+__global__ void print_function() {
+  // printf("%u\n", insert_value);
+#ifdef TEST_BOUNDS
+  printf("%u %u\n", index_min, index_max);
+#endif
+}
+
+int main(int argc, char const *argv[]) {
+  size_t test_size;
+  if (argc == 1) {
+    test_size = 1048576;
+  } else {
+    try {
+      test_size = std::stol(argv[1]);
+    } catch (...) {
+      return 1;
+    }
+  }
+
+  FILE *file = fopen("normal_distribution.txt", "r");
+  assert(file);
+  for (long long i; fscanf(file, "%lld ", &i) != EOF; store_into_vector(i))
+    ;
+  fclose(file);
+
+  assert(population_vector.size() == length);
+
+  sample_vector = std::vector<unsigned long long>(
+      population_vector.begin(), population_vector.begin() + SAMPLE_LENGTH - 2);
+  sample_vector.push_back(min_value);
+  sample_vector.push_back(max_value);
+
+  std::sort(sample_vector.begin(), sample_vector.end());
+
+  key_type *cudaSample = nullptr, *cudaPopulation = nullptr;
+  cudaMalloc(&cudaSample, sizeof(key_type) * (SAMPLE_LENGTH));
+  cudaMalloc(&cudaPopulation, sizeof(key_type) * TEST_SIZE);
+  cudaMemcpy(cudaSample, &sample_vector[0],
+             sizeof(key_type) * sample_vector.size(), cudaMemcpyHostToDevice);
+  cudaMemcpy(cudaPopulation, &population_vector[SAMPLE_LENGTH],
+             sizeof(key_type) * TEST_SIZE, cudaMemcpyHostToDevice);
+  // memcpy(sample_heap, sample_vector.cbegin(),sizeof(key_type) *(SAMPLE_LENGTH
+  // + 2));
+
+  initCuda<<<1, 1>>>(cudaSample, cudaPopulation);
+  cudaDeviceSynchronize();
+
+  dim3 grid_dim = 2, block_dim = 512;
+
+  unsigned long step = test_size / (grid_dim.x * block_dim.x);
+  printf("step: %lu\n", step);
+  assert(!(test_size % (grid_dim.x * block_dim.x)));
+
+  for (int scale = 2; scale <= 8; scale++) {
+    const long split_size = test_size * scale;
+    const auto slice_size = 1.0 / (double)split_size;
+    printf("scale: %i ", scale);
+    initStorage<<<1, 1>>>(scale, test_size);
+    cudaDeviceSynchronize();
+    cudaEvent_t start, stop;
+    cudaEventCreate(&start);
+    cudaEventCreate(&stop);
+    cudaEventRecord(start, nullptr);
+    kernel<<<grid_dim, block_dim>>>(step, slice_size, split_size);
+    cudaDeviceSynchronize();
+    cudaEventRecord(stop, nullptr);
+    cudaEventSynchronize(stop);
+    float time;
+    cudaEventElapsedTime(&time, start, stop);
+    cudaEventDestroy(start);
+    cudaEventDestroy(stop);
+
+    printf("time: %lf\n", time);
+    print_function<<<1, 1>>>();
+    cudaDeviceSynchronize();
+  }
+  return 0;
+}
\ No newline at end of file
diff --git a/normal_distribution.cpp b/normal_distribution.cpp
index 72f914c..e9c646f 100644
--- a/normal_distribution.cpp
+++ b/normal_distribution.cpp
@@ -5,8 +5,45 @@
 #include <set>
 #include <vector>
 
+inline void
+store_into_vector(unsigned long long value, unsigned long long &max_value,
+                  unsigned long long &min_value,
+                  std::vector<unsigned long long> &population_vector) {
+  if (max_value < value) {
+    max_value = value;
+  }
+  if (min_value > value) {
+    min_value = value;
+  }
+  population_vector.push_back(value);
+}
+
+void checkFileValid(const std::string &name, size_t length) {
+
+  std::vector<unsigned long long> vector;
+  unsigned long long max_value = 0, min_value = 0xfffffffffffff;
+  FILE *file = fopen(name.c_str(), "r");
+  assert(file);
+  for (long long i; fscanf(file, "%lld ", &i) != EOF;
+       store_into_vector(i, max_value, min_value, vector))
+    ;
+  ;
+  fclose(file);
+
+  vector.resize(length);
+  for (auto element : vector) {
+    assert(element != max_value);
+    assert(element != min_value);
+  }
+}
+
 int main(int argc, char const *argv[]) {
 
+  if (argc == 3) {
+    checkFileValid(argv[1], std::stol(argv[2]));
+    return 0;
+  }
+
   std::random_device randomDevice;
   std::mt19937 randomEngine(randomDevice());
   std::normal_distribution<long double> normalDistribution(2147483648,
@@ -35,7 +72,6 @@ int main(int argc, char const *argv[]) {
     auto ret = set.insert(element);
     if (ret.second) {
       vector.push_back(element);
-      // TODO: add offset
       // printf("%lld\n", element);
     }
   }