Parallelize-vecop-program-execution

icicle/backend/cpu/src/field/cpu_vec_ops.cpp

@@ -10,6 +10,7 @@
 #include <sys/types.h>
 #include <vector>
 
+#include "taskflow/taskflow.hpp"
 #include "icicle/program/program.h"
 #include "cpu_program_executor.h"
 
@@ -852,20 +853,36 @@ eIcicleError cpu_execute_program(
                      << " parameters";
     return eIcicleError::INVALID_ARGUMENT;
   }
+  tf::Taskflow taskflow; // Accumulate tasks
+  tf::Executor executor; // execute all tasks accumulated on multiple threads
   const uint64_t total_nof_operations = size * config.batch_size;
-  CpuProgramExecutor prog_executor(program);
-  // init prog_executor to point to data vectors
-  for (int param_idx = 0; param_idx < program.m_nof_parameters; ++param_idx) {
-    prog_executor.m_variable_ptrs[param_idx] = data[param_idx];
-  }
 
-  // run over all elements in the arrays and execute the program
-  for (uint64_t i = 0; i < total_nof_operations; i++) {
-    prog_executor.execute();
-    for (int param_idx = 0; param_idx < program.m_nof_parameters; ++param_idx) {
-      (prog_executor.m_variable_ptrs[param_idx])++;
-    }
+  // Divide the problem to workers
+  const int nof_workers = get_nof_workers(config);
+  const uint64_t worker_task_size = (total_nof_operations + nof_workers - 1) / nof_workers; // round up
+
+  for (uint64_t start_idx = 0; start_idx < total_nof_operations; start_idx += worker_task_size) {
+    taskflow.emplace([=]() {
+      CpuProgramExecutor prog_executor(program);
+      // init prog_executor to point to data vectors
+      for (int param_idx = 0; param_idx < program.m_nof_parameters; ++param_idx) {
+        prog_executor.m_variable_ptrs[param_idx] = &(data[param_idx][start_idx]);
+      }
+
+      const uint64_t task_size = std::min(worker_task_size, total_nof_operations - start_idx);
+      // run over all task elements in the arrays and execute the program
+      for (uint64_t i = 0; i < task_size; i++) {
+        prog_executor.execute();
+        // update the program pointers
+        for (int param_idx = 0; param_idx < program.m_nof_parameters; ++param_idx) {
+          (prog_executor.m_variable_ptrs[param_idx])++;
+        }
+      }
+    });
   }
+
+  executor.run(taskflow).wait();
+  taskflow.clear();
   return eIcicleError::SUCCESS;
 }