Summary

A. Device Runtime Support
The Runtime support and Environment variable for Device offloading in OpenMP include:
  • Runtime support routines
  • - void omp_set_default_device(int dev_num)
    - void omp_get_default_device(void)
    - void omp_get_num_device(void)
    - void omp_get_num_teams(void)
    - void omp_get_team_num(void)
    - void omp_is_initial_device(void)
  • Environment variable
  • -control default device through OMP_DEAFAULT_DEVICE which should be
    B. What is new in OpenMP 4.5?
    - Unstructured data mapping by adding enter and exit clauses to Target data map.
    - Asynchronous execution by adding nowait and dep clauses in Target construct.
    - New Device Memory API routines.
    - Supports for device pointers.
    - New Combined constructs.
    - Efficient global mapping for variables by using declare target link.