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OpenMP Reference Sheet for C/C++

Constructs#pragma omp parallel for [shared(vars), private(vars), firstprivate(vars),lastprivate(vars), default(shared|none), reduction(op:vars), copyin(vars), if(expr),ordered, schedule(type[,chunkSize])]for(A=C;A

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copyin(vars)

if(expr)schedule(type [,chunkSize])

type chunkSize

static number of iterations per thread pre-assigned at beginning of loop(typical default is number of processors)

dynamic number of iterations to allocate to a thread when available (typicaldefault is 1)

guided highly dependent on specific implementation of OpenMP

nowait

Synchronization/Locking Constructs

#pragma omp master {

void omp_init_[nest_]lock(omp_lock_t*) void omp_destroy_[nest_]lock(omp_lock_t*) void omp_set_[nest_]lock(omp_lock_t*) void omp_unset_[nest_]lock(omp_lock_t*)

int omp_test_[nest_]lock(omp_lock_t*)

Settings and Controlint omp_get_num_threads() int omp_get_thread_num ()

int omp_in_parallel() int omp_get_max_threads()

int omp_get_num_procs () int omp_get_dynamic() int omp_get_nested() double omp_get_wtime() double omp_get_wtick() void omp_set_num_threads (int) void omp_set_dynamic(int) void omp_set_nested(int)

OMP_NUM_THREADS "number" OMP_SCHEDULE "type,chunkSize"

Legendvars is a comma separated list of variables[optional parameters and directives].... above directive can be used multiple timesFor mistakes, suggestions, and comments please email e_berta@plutospin.com