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| // RUN: %libomp-cxx-compile-and-run
#include <stdio.h>
#include <omp.h>
#define NT 4
#define INIT 10
/*
The test emulates code generation needed for reduction with task modifier on
parallel construct.
Note: tasks could just use in_reduction clause, but compiler does not accept
this because of bug: it mistakenly requires reduction item to be shared, which
is only true for reduction on worksharing and wrong for task reductions.
*/
//------------------------------------------------
// OpenMP runtime library routines
#ifdef __cplusplus
extern "C" {
#endif
extern void *__kmpc_task_reduction_get_th_data(int gtid, void *tg, void *item);
// extern void* __kmpc_task_reduction_modifier_init(void *loc, int gtid, int
// flags, int num, void* data);
extern void *__kmpc_taskred_modifier_init(void *loc, int gtid, int is_ws,
int num, void *data);
extern void __kmpc_task_reduction_modifier_fini(void *loc, int gtid, int is_ws);
extern int __kmpc_global_thread_num(void *);
#ifdef __cplusplus
}
#endif
//------------------------------------------------
// Compiler-generated code
typedef struct red_input {
void *reduce_shar; /**< shared between tasks item to reduce into */
void *reduce_orig; /**< original reduction item used for initialization */
size_t reduce_size; /**< size of data item in bytes */
// three compiler-generated routines (init, fini are optional):
void *reduce_init; /**< data initialization routine (single paramemter) */
void *reduce_fini; /**< data finalization routine */
void *reduce_comb; /**< data combiner routine */
unsigned flags; /**< flags for additional info from compiler */
} red_input_t;
void i_comb(void *lhs, void *rhs) { *(int *)lhs += *(int *)rhs; }
int main() {
int var = INIT;
int *p_var_orig = &var;
int i;
omp_set_dynamic(0);
omp_set_num_threads(NT);
#pragma omp parallel private(i) shared(p_var_orig)
// #pragma omp for reduction(task,+:var)
#pragma omp for reduction(+ : var)
for (i = 0; i < NT; ++i) // single iteration per thread
{
// generated code, which actually should be placed before
// loop iterations distribution, but placed here just to show the idea,
// and to keep correctness the loop count is equal to number of threads
int gtid = __kmpc_global_thread_num(NULL);
void *tg; // pointer to taskgroup (optional)
red_input_t r_var;
r_var.reduce_shar = &var;
r_var.reduce_orig =
p_var_orig; // not used in this test but illustrates codegen
r_var.reduce_size = sizeof(var);
r_var.reduce_init = NULL;
r_var.reduce_fini = NULL;
r_var.reduce_comb = (void *)&i_comb;
tg = __kmpc_taskred_modifier_init(
NULL, // ident_t loc;
gtid,
1, // 1 - worksharing construct, 0 - parallel
1, // number of reduction objects
&r_var // related data
);
// end of generated code
var++;
#pragma omp task /*in_reduction(+:var)*/ shared(var)
{
// emulate task reduction here because of compiler bug:
// it mistakenly declines to accept in_reduction because var is private
// outside.
int gtid = __kmpc_global_thread_num(NULL);
int *p_var = (int *)__kmpc_task_reduction_get_th_data(gtid, tg, &var);
*p_var += 1;
}
if (omp_get_thread_num() > 0) {
#pragma omp task /*in_reduction(+:var)*/ shared(var)
{
int gtid = __kmpc_global_thread_num(NULL);
int *p_var = (int *)__kmpc_task_reduction_get_th_data(gtid, tg, &var);
*p_var += 1;
}
}
// generated code, which actually should be placed after loop completion
// but before barrier and before loop reduction. It placed here just to show
// the idea,
// and to keep correctness the loop count is equal to number of threads
__kmpc_task_reduction_modifier_fini(NULL, gtid, 1);
// end of generated code
}
if (var == INIT + NT * 3 - 1) {
printf("passed\n");
return 0;
} else {
printf("failed: var = %d (!= %d)\n", var, INIT + NT * 3 - 1);
return 1;
}
}
|