blob: 4efd12bac8aa81cbb02bb7162864bf5297347e6e [file] [log] [blame]
/*
* kmp_taskdeps.cpp
*/
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.txt for details.
//
//===----------------------------------------------------------------------===//
//#define KMP_SUPPORT_GRAPH_OUTPUT 1
#include "kmp.h"
#include "kmp_io.h"
#include "kmp_wait_release.h"
#if OMPT_SUPPORT
#include "ompt-specific.h"
#endif
#if OMP_40_ENABLED
// TODO: Improve memory allocation? keep a list of pre-allocated structures?
// allocate in blocks? re-use list finished list entries?
// TODO: don't use atomic ref counters for stack-allocated nodes.
// TODO: find an alternate to atomic refs for heap-allocated nodes?
// TODO: Finish graph output support
// TODO: kmp_lock_t seems a tad to big (and heavy weight) for this. Check other
// runtime locks
// TODO: Any ITT support needed?
#ifdef KMP_SUPPORT_GRAPH_OUTPUT
static std::atomic<kmp_int32> kmp_node_id_seed = ATOMIC_VAR_INIT(0);
#endif
static void __kmp_init_node(kmp_depnode_t *node) {
node->dn.task = NULL; // set to null initially, it will point to the right
// task once dependences have been processed
node->dn.successors = NULL;
__kmp_init_lock(&node->dn.lock);
KMP_ATOMIC_ST_RLX(&node->dn.nrefs,
1); // init creates the first reference to the node
#ifdef KMP_SUPPORT_GRAPH_OUTPUT
node->dn.id = KMP_ATOMIC_INC(&kmp_node_id_seed);
#endif
}
static inline kmp_depnode_t *__kmp_node_ref(kmp_depnode_t *node) {
KMP_ATOMIC_INC(&node->dn.nrefs);
return node;
}
static inline void __kmp_node_deref(kmp_info_t *thread, kmp_depnode_t *node) {
if (!node)
return;
kmp_int32 n = KMP_ATOMIC_DEC(&node->dn.nrefs) - 1;
if (n == 0) {
KMP_ASSERT(node->dn.nrefs == 0);
#if USE_FAST_MEMORY
__kmp_fast_free(thread, node);
#else
__kmp_thread_free(thread, node);
#endif
}
}
#define KMP_ACQUIRE_DEPNODE(gtid, n) __kmp_acquire_lock(&(n)->dn.lock, (gtid))
#define KMP_RELEASE_DEPNODE(gtid, n) __kmp_release_lock(&(n)->dn.lock, (gtid))
static void __kmp_depnode_list_free(kmp_info_t *thread, kmp_depnode_list *list);
enum { KMP_DEPHASH_OTHER_SIZE = 97, KMP_DEPHASH_MASTER_SIZE = 997 };
static inline kmp_int32 __kmp_dephash_hash(kmp_intptr_t addr, size_t hsize) {
// TODO alternate to try: set = (((Addr64)(addrUsefulBits * 9.618)) %
// m_num_sets );
return ((addr >> 6) ^ (addr >> 2)) % hsize;
}
static kmp_dephash_t *__kmp_dephash_create(kmp_info_t *thread,
kmp_taskdata_t *current_task) {
kmp_dephash_t *h;
size_t h_size;
if (current_task->td_flags.tasktype == TASK_IMPLICIT)
h_size = KMP_DEPHASH_MASTER_SIZE;
else
h_size = KMP_DEPHASH_OTHER_SIZE;
kmp_int32 size =
h_size * sizeof(kmp_dephash_entry_t *) + sizeof(kmp_dephash_t);
#if USE_FAST_MEMORY
h = (kmp_dephash_t *)__kmp_fast_allocate(thread, size);
#else
h = (kmp_dephash_t *)__kmp_thread_malloc(thread, size);
#endif
h->size = h_size;
#ifdef KMP_DEBUG
h->nelements = 0;
h->nconflicts = 0;
#endif
h->buckets = (kmp_dephash_entry **)(h + 1);
for (size_t i = 0; i < h_size; i++)
h->buckets[i] = 0;
return h;
}
void __kmp_dephash_free_entries(kmp_info_t *thread, kmp_dephash_t *h) {
for (size_t i = 0; i < h->size; i++) {
if (h->buckets[i]) {
kmp_dephash_entry_t *next;
for (kmp_dephash_entry_t *entry = h->buckets[i]; entry; entry = next) {
next = entry->next_in_bucket;
__kmp_depnode_list_free(thread, entry->last_ins);
__kmp_node_deref(thread, entry->last_out);
#if USE_FAST_MEMORY
__kmp_fast_free(thread, entry);
#else
__kmp_thread_free(thread, entry);
#endif
}
h->buckets[i] = 0;
}
}
}
void __kmp_dephash_free(kmp_info_t *thread, kmp_dephash_t *h) {
__kmp_dephash_free_entries(thread, h);
#if USE_FAST_MEMORY
__kmp_fast_free(thread, h);
#else
__kmp_thread_free(thread, h);
#endif
}
static kmp_dephash_entry *
__kmp_dephash_find(kmp_info_t *thread, kmp_dephash_t *h, kmp_intptr_t addr) {
kmp_int32 bucket = __kmp_dephash_hash(addr, h->size);
kmp_dephash_entry_t *entry;
for (entry = h->buckets[bucket]; entry; entry = entry->next_in_bucket)
if (entry->addr == addr)
break;
if (entry == NULL) {
// create entry. This is only done by one thread so no locking required
#if USE_FAST_MEMORY
entry = (kmp_dephash_entry_t *)__kmp_fast_allocate(
thread, sizeof(kmp_dephash_entry_t));
#else
entry = (kmp_dephash_entry_t *)__kmp_thread_malloc(
thread, sizeof(kmp_dephash_entry_t));
#endif
entry->addr = addr;
entry->last_out = NULL;
entry->last_ins = NULL;
entry->next_in_bucket = h->buckets[bucket];
h->buckets[bucket] = entry;
#ifdef KMP_DEBUG
h->nelements++;
if (entry->next_in_bucket)
h->nconflicts++;
#endif
}
return entry;
}
static kmp_depnode_list_t *__kmp_add_node(kmp_info_t *thread,
kmp_depnode_list_t *list,
kmp_depnode_t *node) {
kmp_depnode_list_t *new_head;
#if USE_FAST_MEMORY
new_head = (kmp_depnode_list_t *)__kmp_fast_allocate(
thread, sizeof(kmp_depnode_list_t));
#else
new_head = (kmp_depnode_list_t *)__kmp_thread_malloc(
thread, sizeof(kmp_depnode_list_t));
#endif
new_head->node = __kmp_node_ref(node);
new_head->next = list;
return new_head;
}
static void __kmp_depnode_list_free(kmp_info_t *thread,
kmp_depnode_list *list) {
kmp_depnode_list *next;
for (; list; list = next) {
next = list->next;
__kmp_node_deref(thread, list->node);
#if USE_FAST_MEMORY
__kmp_fast_free(thread, list);
#else
__kmp_thread_free(thread, list);
#endif
}
}
static inline void __kmp_track_dependence(kmp_depnode_t *source,
kmp_depnode_t *sink,
kmp_task_t *sink_task) {
#ifdef KMP_SUPPORT_GRAPH_OUTPUT
kmp_taskdata_t *task_source = KMP_TASK_TO_TASKDATA(source->dn.task);
// do not use sink->dn.task as that is only filled after the dependencies
// are already processed!
kmp_taskdata_t *task_sink = KMP_TASK_TO_TASKDATA(sink_task);
__kmp_printf("%d(%s) -> %d(%s)\n", source->dn.id,
task_source->td_ident->psource, sink->dn.id,
task_sink->td_ident->psource);
#endif
#if OMPT_SUPPORT && OMPT_OPTIONAL
/* OMPT tracks dependences between task (a=source, b=sink) in which
task a blocks the execution of b through the ompt_new_dependence_callback
*/
if (ompt_enabled.ompt_callback_task_dependence) {
kmp_taskdata_t *task_source = KMP_TASK_TO_TASKDATA(source->dn.task);
kmp_taskdata_t *task_sink = KMP_TASK_TO_TASKDATA(sink_task);
ompt_callbacks.ompt_callback(ompt_callback_task_dependence)(
&(task_source->ompt_task_info.task_data),
&(task_sink->ompt_task_info.task_data));
}
#endif /* OMPT_SUPPORT && OMPT_OPTIONAL */
}
template <bool filter>
static inline kmp_int32
__kmp_process_deps(kmp_int32 gtid, kmp_depnode_t *node, kmp_dephash_t *hash,
bool dep_barrier, kmp_int32 ndeps,
kmp_depend_info_t *dep_list, kmp_task_t *task) {
KA_TRACE(30, ("__kmp_process_deps<%d>: T#%d processing %d dependencies : "
"dep_barrier = %d\n",
filter, gtid, ndeps, dep_barrier));
kmp_info_t *thread = __kmp_threads[gtid];
kmp_int32 npredecessors = 0;
for (kmp_int32 i = 0; i < ndeps; i++) {
const kmp_depend_info_t *dep = &dep_list[i];
KMP_DEBUG_ASSERT(dep->flags.in);
if (filter && dep->base_addr == 0)
continue; // skip filtered entries
kmp_dephash_entry_t *info =
__kmp_dephash_find(thread, hash, dep->base_addr);
kmp_depnode_t *last_out = info->last_out;
if (dep->flags.out && info->last_ins) {
for (kmp_depnode_list_t *p = info->last_ins; p; p = p->next) {
kmp_depnode_t *indep = p->node;
if (indep->dn.task) {
KMP_ACQUIRE_DEPNODE(gtid, indep);
if (indep->dn.task) {
__kmp_track_dependence(indep, node, task);
indep->dn.successors =
__kmp_add_node(thread, indep->dn.successors, node);
KA_TRACE(40, ("__kmp_process_deps<%d>: T#%d adding dependence from "
"%p to %p\n",
filter, gtid, KMP_TASK_TO_TASKDATA(indep->dn.task),
KMP_TASK_TO_TASKDATA(task)));
npredecessors++;
}
KMP_RELEASE_DEPNODE(gtid, indep);
}
}
__kmp_depnode_list_free(thread, info->last_ins);
info->last_ins = NULL;
} else if (last_out && last_out->dn.task) {
KMP_ACQUIRE_DEPNODE(gtid, last_out);
if (last_out->dn.task) {
__kmp_track_dependence(last_out, node, task);
last_out->dn.successors =
__kmp_add_node(thread, last_out->dn.successors, node);
KA_TRACE(
40,
("__kmp_process_deps<%d>: T#%d adding dependence from %p to %p\n",
filter, gtid, KMP_TASK_TO_TASKDATA(last_out->dn.task),
KMP_TASK_TO_TASKDATA(task)));
npredecessors++;
}
KMP_RELEASE_DEPNODE(gtid, last_out);
}
if (dep_barrier) {
// if this is a sync point in the serial sequence, then the previous
// outputs are guaranteed to be completed after
// the execution of this task so the previous output nodes can be cleared.
__kmp_node_deref(thread, last_out);
info->last_out = NULL;
} else {
if (dep->flags.out) {
__kmp_node_deref(thread, last_out);
info->last_out = __kmp_node_ref(node);
} else
info->last_ins = __kmp_add_node(thread, info->last_ins, node);
}
}
KA_TRACE(30, ("__kmp_process_deps<%d>: T#%d found %d predecessors\n", filter,
gtid, npredecessors));
return npredecessors;
}
#define NO_DEP_BARRIER (false)
#define DEP_BARRIER (true)
// returns true if the task has any outstanding dependence
static bool __kmp_check_deps(kmp_int32 gtid, kmp_depnode_t *node,
kmp_task_t *task, kmp_dephash_t *hash,
bool dep_barrier, kmp_int32 ndeps,
kmp_depend_info_t *dep_list,
kmp_int32 ndeps_noalias,
kmp_depend_info_t *noalias_dep_list) {
int i;
#if KMP_DEBUG
kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task);
#endif
KA_TRACE(20, ("__kmp_check_deps: T#%d checking dependencies for task %p : %d "
"possibly aliased dependencies, %d non-aliased depedencies : "
"dep_barrier=%d .\n",
gtid, taskdata, ndeps, ndeps_noalias, dep_barrier));
// Filter deps in dep_list
// TODO: Different algorithm for large dep_list ( > 10 ? )
for (i = 0; i < ndeps; i++) {
if (dep_list[i].base_addr != 0)
for (int j = i + 1; j < ndeps; j++)
if (dep_list[i].base_addr == dep_list[j].base_addr) {
dep_list[i].flags.in |= dep_list[j].flags.in;
dep_list[i].flags.out |= dep_list[j].flags.out;
dep_list[j].base_addr = 0; // Mark j element as void
}
}
// doesn't need to be atomic as no other thread is going to be accessing this
// node just yet.
// npredecessors is set -1 to ensure that none of the releasing tasks queues
// this task before we have finished processing all the dependencies
node->dn.npredecessors = -1;
// used to pack all npredecessors additions into a single atomic operation at
// the end
int npredecessors;
npredecessors = __kmp_process_deps<true>(gtid, node, hash, dep_barrier, ndeps,
dep_list, task);
npredecessors += __kmp_process_deps<false>(
gtid, node, hash, dep_barrier, ndeps_noalias, noalias_dep_list, task);
node->dn.task = task;
KMP_MB();
// Account for our initial fake value
npredecessors++;
// Update predecessors and obtain current value to check if there are still
// any outstandig dependences (some tasks may have finished while we processed
// the dependences)
npredecessors =
node->dn.npredecessors.fetch_add(npredecessors) + npredecessors;
KA_TRACE(20, ("__kmp_check_deps: T#%d found %d predecessors for task %p \n",
gtid, npredecessors, taskdata));
// beyond this point the task could be queued (and executed) by a releasing
// task...
return npredecessors > 0 ? true : false;
}
void __kmp_release_deps(kmp_int32 gtid, kmp_taskdata_t *task) {
kmp_info_t *thread = __kmp_threads[gtid];
kmp_depnode_t *node = task->td_depnode;
if (task->td_dephash) {
KA_TRACE(
40, ("__kmp_release_deps: T#%d freeing dependencies hash of task %p.\n",
gtid, task));
__kmp_dephash_free(thread, task->td_dephash);
task->td_dephash = NULL;
}
if (!node)
return;
KA_TRACE(20, ("__kmp_release_deps: T#%d notifying successors of task %p.\n",
gtid, task));
KMP_ACQUIRE_DEPNODE(gtid, node);
node->dn.task =
NULL; // mark this task as finished, so no new dependencies are generated
KMP_RELEASE_DEPNODE(gtid, node);
kmp_depnode_list_t *next;
for (kmp_depnode_list_t *p = node->dn.successors; p; p = next) {
kmp_depnode_t *successor = p->node;
kmp_int32 npredecessors = KMP_ATOMIC_DEC(&successor->dn.npredecessors) - 1;
// successor task can be NULL for wait_depends or because deps are still
// being processed
if (npredecessors == 0) {
KMP_MB();
if (successor->dn.task) {
KA_TRACE(20, ("__kmp_release_deps: T#%d successor %p of %p scheduled "
"for execution.\n",
gtid, successor->dn.task, task));
__kmp_omp_task(gtid, successor->dn.task, false);
}
}
next = p->next;
__kmp_node_deref(thread, p->node);
#if USE_FAST_MEMORY
__kmp_fast_free(thread, p);
#else
__kmp_thread_free(thread, p);
#endif
}
__kmp_node_deref(thread, node);
KA_TRACE(
20,
("__kmp_release_deps: T#%d all successors of %p notified of completion\n",
gtid, task));
}
/*!
@ingroup TASKING
@param loc_ref location of the original task directive
@param gtid Global Thread ID of encountering thread
@param new_task task thunk allocated by __kmp_omp_task_alloc() for the ''new
task''
@param ndeps Number of depend items with possible aliasing
@param dep_list List of depend items with possible aliasing
@param ndeps_noalias Number of depend items with no aliasing
@param noalias_dep_list List of depend items with no aliasing
@return Returns either TASK_CURRENT_NOT_QUEUED if the current task was not
suspendend and queued, or TASK_CURRENT_QUEUED if it was suspended and queued
Schedule a non-thread-switchable task with dependences for execution
*/
kmp_int32 __kmpc_omp_task_with_deps(ident_t *loc_ref, kmp_int32 gtid,
kmp_task_t *new_task, kmp_int32 ndeps,
kmp_depend_info_t *dep_list,
kmp_int32 ndeps_noalias,
kmp_depend_info_t *noalias_dep_list) {
kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task);
KA_TRACE(10, ("__kmpc_omp_task_with_deps(enter): T#%d loc=%p task=%p\n", gtid,
loc_ref, new_taskdata));
kmp_info_t *thread = __kmp_threads[gtid];
kmp_taskdata_t *current_task = thread->th.th_current_task;
#if OMPT_SUPPORT
if (ompt_enabled.enabled) {
OMPT_STORE_RETURN_ADDRESS(gtid);
if (!current_task->ompt_task_info.frame.enter_frame)
current_task->ompt_task_info.frame.enter_frame =
OMPT_GET_FRAME_ADDRESS(1);
if (ompt_enabled.ompt_callback_task_create) {
ompt_data_t task_data = ompt_data_none;
ompt_callbacks.ompt_callback(ompt_callback_task_create)(
current_task ? &(current_task->ompt_task_info.task_data) : &task_data,
current_task ? &(current_task->ompt_task_info.frame) : NULL,
&(new_taskdata->ompt_task_info.task_data),
ompt_task_explicit | TASK_TYPE_DETAILS_FORMAT(new_taskdata), 1,
OMPT_LOAD_RETURN_ADDRESS(gtid));
}
new_taskdata->ompt_task_info.frame.enter_frame = OMPT_GET_FRAME_ADDRESS(0);
}
#if OMPT_OPTIONAL
/* OMPT grab all dependences if requested by the tool */
if (ndeps + ndeps_noalias > 0 &&
ompt_enabled.ompt_callback_task_dependences) {
kmp_int32 i;
new_taskdata->ompt_task_info.ndeps = ndeps + ndeps_noalias;
new_taskdata->ompt_task_info.deps =
(ompt_task_dependence_t *)KMP_OMPT_DEPS_ALLOC(
thread, (ndeps + ndeps_noalias) * sizeof(ompt_task_dependence_t));
KMP_ASSERT(new_taskdata->ompt_task_info.deps != NULL);
for (i = 0; i < ndeps; i++) {
new_taskdata->ompt_task_info.deps[i].variable_addr =
(void *)dep_list[i].base_addr;
if (dep_list[i].flags.in && dep_list[i].flags.out)
new_taskdata->ompt_task_info.deps[i].dependence_flags =
ompt_task_dependence_type_inout;
else if (dep_list[i].flags.out)
new_taskdata->ompt_task_info.deps[i].dependence_flags =
ompt_task_dependence_type_out;
else if (dep_list[i].flags.in)
new_taskdata->ompt_task_info.deps[i].dependence_flags =
ompt_task_dependence_type_in;
}
for (i = 0; i < ndeps_noalias; i++) {
new_taskdata->ompt_task_info.deps[ndeps + i].variable_addr =
(void *)noalias_dep_list[i].base_addr;
if (noalias_dep_list[i].flags.in && noalias_dep_list[i].flags.out)
new_taskdata->ompt_task_info.deps[ndeps + i].dependence_flags =
ompt_task_dependence_type_inout;
else if (noalias_dep_list[i].flags.out)
new_taskdata->ompt_task_info.deps[ndeps + i].dependence_flags =
ompt_task_dependence_type_out;
else if (noalias_dep_list[i].flags.in)
new_taskdata->ompt_task_info.deps[ndeps + i].dependence_flags =
ompt_task_dependence_type_in;
}
ompt_callbacks.ompt_callback(ompt_callback_task_dependences)(
&(new_taskdata->ompt_task_info.task_data),
new_taskdata->ompt_task_info.deps, new_taskdata->ompt_task_info.ndeps);
/* We can now free the allocated memory for the dependencies */
/* For OMPD we might want to delay the free until task_end */
KMP_OMPT_DEPS_FREE(thread, new_taskdata->ompt_task_info.deps);
new_taskdata->ompt_task_info.deps = NULL;
new_taskdata->ompt_task_info.ndeps = 0;
}
#endif /* OMPT_OPTIONAL */
#endif /* OMPT_SUPPORT */
bool serial = current_task->td_flags.team_serial ||
current_task->td_flags.tasking_ser ||
current_task->td_flags.final;
#if OMP_45_ENABLED
kmp_task_team_t *task_team = thread->th.th_task_team;
serial = serial && !(task_team && task_team->tt.tt_found_proxy_tasks);
#endif
if (!serial && (ndeps > 0 || ndeps_noalias > 0)) {
/* if no dependencies have been tracked yet, create the dependence hash */
if (current_task->td_dephash == NULL)
current_task->td_dephash = __kmp_dephash_create(thread, current_task);
#if USE_FAST_MEMORY
kmp_depnode_t *node =
(kmp_depnode_t *)__kmp_fast_allocate(thread, sizeof(kmp_depnode_t));
#else
kmp_depnode_t *node =
(kmp_depnode_t *)__kmp_thread_malloc(thread, sizeof(kmp_depnode_t));
#endif
__kmp_init_node(node);
new_taskdata->td_depnode = node;
if (__kmp_check_deps(gtid, node, new_task, current_task->td_dephash,
NO_DEP_BARRIER, ndeps, dep_list, ndeps_noalias,
noalias_dep_list)) {
KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d task had blocking "
"dependencies: "
"loc=%p task=%p, return: TASK_CURRENT_NOT_QUEUED\n",
gtid, loc_ref, new_taskdata));
#if OMPT_SUPPORT
if (ompt_enabled.enabled) {
current_task->ompt_task_info.frame.enter_frame = NULL;
}
#endif
return TASK_CURRENT_NOT_QUEUED;
}
} else {
KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d ignored dependencies "
"for task (serialized)"
"loc=%p task=%p\n",
gtid, loc_ref, new_taskdata));
}
KA_TRACE(10, ("__kmpc_omp_task_with_deps(exit): T#%d task had no blocking "
"dependencies : "
"loc=%p task=%p, transferring to __kmpc_omp_task\n",
gtid, loc_ref, new_taskdata));
kmp_int32 ret = __kmp_omp_task(gtid, new_task, true);
#if OMPT_SUPPORT
if (ompt_enabled.enabled) {
current_task->ompt_task_info.frame.enter_frame = NULL;
}
#endif
return ret;
}
/*!
@ingroup TASKING
@param loc_ref location of the original task directive
@param gtid Global Thread ID of encountering thread
@param ndeps Number of depend items with possible aliasing
@param dep_list List of depend items with possible aliasing
@param ndeps_noalias Number of depend items with no aliasing
@param noalias_dep_list List of depend items with no aliasing
Blocks the current task until all specifies dependencies have been fulfilled.
*/
void __kmpc_omp_wait_deps(ident_t *loc_ref, kmp_int32 gtid, kmp_int32 ndeps,
kmp_depend_info_t *dep_list, kmp_int32 ndeps_noalias,
kmp_depend_info_t *noalias_dep_list) {
KA_TRACE(10, ("__kmpc_omp_wait_deps(enter): T#%d loc=%p\n", gtid, loc_ref));
if (ndeps == 0 && ndeps_noalias == 0) {
KA_TRACE(10, ("__kmpc_omp_wait_deps(exit): T#%d has no dependencies to "
"wait upon : loc=%p\n",
gtid, loc_ref));
return;
}
kmp_info_t *thread = __kmp_threads[gtid];
kmp_taskdata_t *current_task = thread->th.th_current_task;
// We can return immediately as:
// - dependences are not computed in serial teams (except with proxy tasks)
// - if the dephash is not yet created it means we have nothing to wait for
bool ignore = current_task->td_flags.team_serial ||
current_task->td_flags.tasking_ser ||
current_task->td_flags.final;
#if OMP_45_ENABLED
ignore = ignore && thread->th.th_task_team != NULL &&
thread->th.th_task_team->tt.tt_found_proxy_tasks == FALSE;
#endif
ignore = ignore || current_task->td_dephash == NULL;
if (ignore) {
KA_TRACE(10, ("__kmpc_omp_wait_deps(exit): T#%d has no blocking "
"dependencies : loc=%p\n",
gtid, loc_ref));
return;
}
kmp_depnode_t node = {0};
__kmp_init_node(&node);
if (!__kmp_check_deps(gtid, &node, NULL, current_task->td_dephash,
DEP_BARRIER, ndeps, dep_list, ndeps_noalias,
noalias_dep_list)) {
KA_TRACE(10, ("__kmpc_omp_wait_deps(exit): T#%d has no blocking "
"dependencies : loc=%p\n",
gtid, loc_ref));
return;
}
int thread_finished = FALSE;
kmp_flag_32 flag((std::atomic<kmp_uint32> *)&node.dn.npredecessors, 0U);
while (node.dn.npredecessors > 0) {
flag.execute_tasks(thread, gtid, FALSE,
&thread_finished USE_ITT_BUILD_ARG(NULL),
__kmp_task_stealing_constraint);
}
KA_TRACE(10, ("__kmpc_omp_wait_deps(exit): T#%d finished waiting : loc=%p\n",
gtid, loc_ref));
}
#endif /* OMP_40_ENABLED */