GPU621/Group 5

Team

1. Ibrahim Muhammad Yusoof
2. Ho Wa Lo

Introduction

Since 2020, there has been a lot of updates to the Mac OS ecosystem, and its command line interface. Which has caused for the dependancy documentation for integrating with Mac OS outdated. So this report is our comprehensive findings for interfacing with the OpenMP, TBB, and MPI libraries on Visual Studio Code to leverage Parallel Computing Concepts that are outlined in this course. As many Software Developers working on Mac already now, Visual Studio for Mac only supports some languages, one of which isn’t C/C++. So we’ll be using the common and popular text editor, Visual Studio Code. Visual Studio Code will allow us to use the command line interface for our compiler to integrate and option the dependancies that we want to use. You should already have downloaded and installed:

• Visual Studio Code,

• If not, you can find the Download and Install for it here: Visual Studio Code - Code Editing. Redefined

• Intel oneAPI Base Toolkit & Intel oneAPI HPC Toolkit

• If not, you can find the Download and Install for it here: Intel oneAPI ToolKits

Note: Installing Visual Studio Code and the HPC packages are not apart of the scope of this report. The installation is straight forward through the wizard.

Vocabulary

Going forward, we’ll be using these terms:

CLI - Command Line Interface

VScode - Visual Studio Code

Integrating

Before we go into specifically each library, let’s talk about how VScode handles compilers. Within VSCode, when we create a .CPP file, we can either run the code in our terminal, or we can create a task that compiles our code before launching the executable with our runtime arguments. We’ll use this **task and launch** method to setup our environment for C++.

Start by creating a regular C++ workspace:

1. Open up VScode and open a directory where you want to code
2. Create a C++ file, for our example we’ll call it: `helloworld.cpp`
3. You can add this code into it for now:

#include <iostream>

int main(int argc, char const *argv[])
{
   std::cout << "Hello world";
   return 0;
}

Tasks

From here, we want to tell VScode what **tasks** to run when we press the Run and Debug button. This will be similar to how we use terminal to build our code.

1. Press Command+Shift+P
2. At the search bar that comes up, type: Tasks: Configure Task and press Enter
3. You’ll may see another option come up, to choose what kind of task, select “C/C++: g++ build active file” (If you don’t have other C/C++ compilers installed, you may not, “C/C++: g++ build active file” will be the default)
4. This will create a folder called .vscode with a JSON file called: tasks.json
5. Open the tasks.json file, it should look like this:

{
   "tasks": [
       {
           "type": "cppbuild",                                 // Type of task
           "label": "C/C++: g++ build active file",            // Label for the task This is important!! for our launch file
           "command": "/usr/bin/g++",                          // Which command will be used
           "args": [                                           // All the arguments that will be used at buildtime
               "-fdiagnostics-color=always",                   // Use Diagnostic colors
               "-g",                                           // Create debugger data to be used
               "${file}",                                      // Compile this file
               "-o",                                           // Output it as 
               "${fileDirname}/${fileBasenameNoExtension}"     // The File name without the .cpp extension
           ],
           "options": {                
               "cwd": "${fileDirname}"                         // The working directory that we'll run our compiler in
           },
           "problemMatcher": [
               "$gcc"
           ],
           "group": {
               "kind": "build",
               "isDefault": true
           },
           "detail": "Task generated by Debugger."
       }
   ],
   "version": "2.0.0"
}

This task tells VScode, when we use this task, run [this].command with [this].args. VScode will inject this into our terminal to automatically compile our code. This will help our VScode Debugger and help our launch task get ready for running our code.

g++ -fdiagnostics-color=always -g helloworld.cpp -o ./helloworld

Launch

Our launch file will facilitate the execution of our code, in the task.json we compiled and produced an output, here we will run our code with the correct information.

1. You can create a **launch.json** file by navigating to the RUN AND DEBUG: RUN section on the left side navigator, (or use Command+Shift+D)
2. You’ll see an option there that says “To customize your Run and Debug create a launch.json file”. Choose this option, it will allow us to pass arguments into our code.
3. This will create a JSON file called launch.json inside the .vscode folder from before. It will look something like this:

{
       // Use IntelliSense to learn about possible attributes.
       // Hover to view descriptions of existing attributes.
       // For more information, visit: [1](https://go.microsoft.com/fwlink/?linkid=830387)
       "version": "0.2.0",
       "configurations": []
}

Find and press the “Add configurations" button near the bottom right, it will let add a template configuration for us to start with

i. You’ll see many options come up, we want to choose “C/C++: (lldb) Launch”.Now our launch.json should look like this:

{
   // Use IntelliSense to learn about possible attributes.
   // Hover to view descriptions of existing attributes.
   // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
   "version": "0.2.0",
   "configurations": [
       {
           "name": "(lldb) Launch",                                                 // Name of our configuration
           "type": "cppdbg",                                                        // Type of Launch (This type is as C++ Debugger) 
           "request": "launch",                                                     // We are requesting to launch our code
           "program": "enter program name, for example ${workspaceFolder}/a.out",   // Here is where we will add the name of our file
           "args": [],                                                              // All arguments we want to use
           "stopAtEntry": false,                                                  
           "cwd": "${fileDirname}",
           "environment": [],
           "externalConsole": false,
           "MIMode": "lldb"
           ///////////////
           // ADD THIS: //
           "preLaunchTask": "C/C++: g++ build active file"                          // This will tell VScode which Task to to 
           //////////////                                                           // |-> setup this launch 
       }
   ]
}

prelaunchTask: The prelaunch task is set to a string that matches the label section in our tasks. It identifies which task needs to run in order for the launch to be successful. This is where you can create multiple launch tasks that setup your files differently. We’ll be adding a task and a launch for all the library we’ll be setting up.

OpenMP

OpenMP

TBB

TBB

MPI

MPI

Testing

OpenMP

{
 // OpenMP - Runtime Routines
 // omp_hi.cpp

 #include <iostream>
 #include <omp.h>

 int main() {

     #pragma omp parallel
     {
         int tid = omp_get_thread_num(); 
         std::cout << "Hi from thread "
          << tid << '\n';
     }
 }
}

TBB

{
 // TBB - Hello World
 // tbb.cpp
 #include <iostream>
 #include <tbb/tbb.h>

 int main() {
     std::cout << "Hello World from TBB "
         << TBB_VERSION_MAJOR << "."
         << TBB_VERSION_MINOR << " ("
          << TBB_INTERFACE_VERSION << ")" << std::endl; 
 }
}

MPI

{
 // MPI Program - Hello World
 // mpi_hello.c

 #include <stdio.h>
 #include <mpi.h>

 int main(int argc, char** argv) {

     int rank, np;

     MPI_Init(&argc, &argv);
     MPI_Comm_rank(MPI_COMM_WORLD, &rank); 
     MPI_Comm_size(MPI_COMM_WORLD, &np);
     printf("Hello from process %d of %d\n", 
      rank, np);
     MPI_Finalize();

     return 0;
 }
}