openmp/runtime/test/tasking/kmp_task_modifier_simple_ws_new.cpp

   1 // RUN: %libomp-cxx-compile-and-run
   2
   3 #include <stdio.h>
   4 #include <omp.h>
   5
   6 #define NT 4
   7 #define INIT 10
   8
   9 /*
  10 The test emulates code generation needed for reduction with task modifier on
  11 parallel construct.
  12
  13 Note: tasks could just use in_reduction clause, but compiler does not accept
  14 this because of bug: it mistakenly requires reduction item to be shared, which
  15 is only true for reduction on worksharing and wrong for task reductions.
  16 */
  17
  18 //------------------------------------------------
  19 // OpenMP runtime library routines
  20 #ifdef __cplusplus
  21 extern "C" {
  22 #endif
  23 extern void *__kmpc_task_reduction_get_th_data(int gtid, void *tg, void *item);
  24 // extern void* __kmpc_task_reduction_modifier_init(void *loc, int gtid, int
  25 // flags, int num, void* data);
  26 extern void *__kmpc_taskred_modifier_init(void *loc, int gtid, int is_ws,
  27                                           int num, void *data);
  28 extern void __kmpc_task_reduction_modifier_fini(void *loc, int gtid, int is_ws);
  29 extern int __kmpc_global_thread_num(void *);
  30 #ifdef __cplusplus
  31 }
  32 #endif
  33
  34 //------------------------------------------------
  35 // Compiler-generated code
  36
  37 typedef struct red_input {
  38   void *reduce_shar; /**< shared between tasks item to reduce into */
  39   void *reduce_orig; /**< original reduction item used for initialization */
  40   size_t reduce_size; /**< size of data item in bytes */
  41   // three compiler-generated routines (init, fini are optional):
  42   void *reduce_init; /**< data initialization routine (single parameter) */
  43   void *reduce_fini; /**< data finalization routine */
  44   void *reduce_comb; /**< data combiner routine */
  45   unsigned flags; /**< flags for additional info from compiler */
  46 } red_input_t;
  47
  48 void i_comb(void *lhs, void *rhs) { *(int *)lhs += *(int *)rhs; }
  49
  50 int main() {
  51   int var = INIT;
  52   int *p_var_orig = &var;
  53   int i;
  54   omp_set_dynamic(0);
  55   omp_set_num_threads(NT);
  56 #pragma omp parallel private(i) shared(p_var_orig)
  57 //  #pragma omp for reduction(task,+:var)
  58 #pragma omp for reduction(+ : var)
  59   for (i = 0; i < NT; ++i) // single iteration per thread
  60   {
  61     // generated code, which actually should be placed before
  62     // loop iterations distribution, but placed here just to show the idea,
  63     // and to keep correctness the loop count is equal to number of threads
  64     int gtid = __kmpc_global_thread_num(NULL);
  65     void *tg; // pointer to taskgroup (optional)
  66     red_input_t r_var;
  67     r_var.reduce_shar = &var;
  68     r_var.reduce_orig =
  69         p_var_orig; // not used in this test but illustrates codegen
  70     r_var.reduce_size = sizeof(var);
  71     r_var.reduce_init = NULL;
  72     r_var.reduce_fini = NULL;
  73     r_var.reduce_comb = (void *)&i_comb;
  74     tg = __kmpc_taskred_modifier_init(
  75         NULL, // ident_t loc;
  76         gtid,
  77         1, // 1 - worksharing construct, 0 - parallel
  78         1, // number of reduction objects
  79         &r_var // related data
  80         );
  81     // end of generated code
  82     var++;
  83 #pragma omp task /*in_reduction(+:var)*/ shared(var)
  84     {
  85       // emulate task reduction here because of compiler bug:
  86       // it mistakenly declines to accept in_reduction because var is private
  87       // outside.
  88       int gtid = __kmpc_global_thread_num(NULL);
  89       int *p_var = (int *)__kmpc_task_reduction_get_th_data(gtid, tg, &var);
  90       *p_var += 1;
  91     }
  92     if (omp_get_thread_num() > 0) {
  93 #pragma omp task /*in_reduction(+:var)*/ shared(var)
  94       {
  95         int gtid = __kmpc_global_thread_num(NULL);
  96         int *p_var = (int *)__kmpc_task_reduction_get_th_data(gtid, tg, &var);
  97         *p_var += 1;
  98       }
  99     }
 100     // generated code, which actually should be placed after loop completion
 101     // but before barrier and before loop reduction. It placed here just to show
 102     // the idea,
 103     // and to keep correctness the loop count is equal to number of threads
 104     __kmpc_task_reduction_modifier_fini(NULL, gtid, 1);
 105     // end of generated code
 106   }
 107   if (var == INIT + NT * 3 - 1) {
 108     printf("passed\n");
 109     return 0;
 110   } else {
 111     printf("failed: var = %d (!= %d)\n", var, INIT + NT * 3 - 1);
 112     return 1;
 113   }
 114 }