From: Jakub Jelinek Date: Tue, 5 Jul 2022 07:11:46 +0000 (+0200) Subject: openmp: Add taskwait nowait depend support [PR105378] X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a25ddca52deba998c1ac6962a690f6ecca6a1ddb;p=thirdparty%2Fgcc.git openmp: Add taskwait nowait depend support [PR105378] This patch adds support for (so far C/C++) #pragma omp taskwait nowait depend(...) directive, which is like #pragma omp task depend(...) ; but slightly optimized on the library side, so that it creates the task only for the purpose of dependency tracking and doesn't actually schedule it and wait for it when the dependencies are satisfied, instead makes its dependencies satisfied right away. 2022-05-24 Jakub Jelinek PR c/105378 gcc/ * omp-builtins.def (BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT): New builtin. * gimplify.cc (gimplify_omp_task): Diagnose taskwait with nowait clause but no depend clauses. * omp-expand.cc (expand_taskwait_call): Use BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT rather than BUILT_IN_GOMP_TASKWAIT_DEPEND if nowait clause is present. gcc/c/ * c-parser.cc (OMP_TASKWAIT_CLAUSE_MASK): Add nowait clause. gcc/cp/ * parser.cc (OMP_TASKWAIT_CLAUSE_MASK): Add nowait clause. gcc/testsuite/ * c-c++-common/gomp/taskwait-depend-nowait-1.c: New test. libgomp/ * libgomp_g.h (GOMP_taskwait_depend_nowait): Declare. * libgomp.map (GOMP_taskwait_depend_nowait): Export at GOMP_5.1.1. * task.c (empty_task): New function. (gomp_task_run_post_handle_depend_hash): Declare earlier. (gomp_task_run_post_handle_depend): Declare. (GOMP_task): Optimize fn == empty_task if there is nothing to wait for. (gomp_task_run_post_handle_dependers): Optimize task->fn == empty_task. (GOMP_taskwait_depend_nowait): New function. * testsuite/libgomp.c-c++-common/taskwait-depend-nowait-1.c: New test. (cherry picked from commit b43836914bdc2a37563cf31359b2c4803bfe4374) --- diff --git a/gcc/ChangeLog.omp b/gcc/ChangeLog.omp index 7592fecddcb3..aa9dabbdd6bc 100644 --- a/gcc/ChangeLog.omp +++ b/gcc/ChangeLog.omp @@ -1,3 +1,17 @@ +2022-07-05 Tobias Burnus + + Backport from mainline: + 2022-05-24 Jakub Jelinek + + PR c/105378 + * omp-builtins.def (BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT): New + builtin. + * gimplify.cc (gimplify_omp_task): Diagnose taskwait with nowait + clause but no depend clauses. + * omp-expand.cc (expand_taskwait_call): Use + BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT rather than + BUILT_IN_GOMP_TASKWAIT_DEPEND if nowait clause is present. + 2022-07-05 Tobias Burnus Backport from mainline: diff --git a/gcc/c/ChangeLog.omp b/gcc/c/ChangeLog.omp index 51d735341f26..2cca133beb3c 100644 --- a/gcc/c/ChangeLog.omp +++ b/gcc/c/ChangeLog.omp @@ -1,3 +1,11 @@ +2022-07-05 Tobias Burnus + + Backport from mainline: + 2022-05-24 Jakub Jelinek + + PR c/105378 + * c-parser.cc (OMP_TASKWAIT_CLAUSE_MASK): Add nowait clause. + 2022-07-04 Tobias Burnus Backport from mainline: diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc index 903063d4c1e5..d9489c298f84 100644 --- a/gcc/c/c-parser.cc +++ b/gcc/c/c-parser.cc @@ -20706,7 +20706,8 @@ c_parser_omp_task (location_t loc, c_parser *parser, bool *if_p) */ #define OMP_TASKWAIT_CLAUSE_MASK \ - (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND) + ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND) \ + | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT)) static void c_parser_omp_taskwait (c_parser *parser) diff --git a/gcc/cp/ChangeLog.omp b/gcc/cp/ChangeLog.omp index 924e0a3ec2e9..49c1994c65c3 100644 --- a/gcc/cp/ChangeLog.omp +++ b/gcc/cp/ChangeLog.omp @@ -1,3 +1,11 @@ +2022-07-05 Tobias Burnus + + Backport from mainline: + 2022-05-24 Jakub Jelinek + + PR c/105378 + * parser.cc (OMP_TASKWAIT_CLAUSE_MASK): Add nowait clause. + 2022-07-04 Tobias Burnus Backport from mainline: diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index 957206cdc0c4..71cfe3f59a30 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -43904,7 +43904,8 @@ cp_parser_omp_task (cp_parser *parser, cp_token *pragma_tok, bool *if_p) # pragma omp taskwait taskwait-clause[opt] new-line */ #define OMP_TASKWAIT_CLAUSE_MASK \ - (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND) + ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND) \ + | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT)) static void cp_parser_omp_taskwait (cp_parser *parser, cp_token *pragma_tok) diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc index f7614ae6caab..5409d4b0b6f6 100644 --- a/gcc/gimplify.cc +++ b/gcc/gimplify.cc @@ -12973,17 +12973,34 @@ gimplify_omp_task (tree *expr_p, gimple_seq *pre_p) tree expr = *expr_p; gimple *g; gimple_seq body = NULL; + bool nowait = false; + bool has_depend = false; if (OMP_TASK_BODY (expr) == NULL_TREE) - for (tree c = OMP_TASK_CLAUSES (expr); c; c = OMP_CLAUSE_CHAIN (c)) - if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEPEND - && OMP_CLAUSE_DEPEND_KIND (c) == OMP_CLAUSE_DEPEND_MUTEXINOUTSET) + { + for (tree c = OMP_TASK_CLAUSES (expr); c; c = OMP_CLAUSE_CHAIN (c)) + if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEPEND) + { + has_depend = true; + if (OMP_CLAUSE_DEPEND_KIND (c) == OMP_CLAUSE_DEPEND_MUTEXINOUTSET) + { + error_at (OMP_CLAUSE_LOCATION (c), + "% kind in % clause on a " + "% construct"); + break; + } + } + else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_NOWAIT) + nowait = true; + if (nowait && !has_depend) { - error_at (OMP_CLAUSE_LOCATION (c), - "% kind in % clause on a " - "% construct"); - break; + error_at (EXPR_LOCATION (expr), + "% construct with % clause but no " + "% clauses"); + *expr_p = NULL_TREE; + return; } + } gimplify_scan_omp_clauses (&OMP_TASK_CLAUSES (expr), pre_p, omp_find_clause (OMP_TASK_CLAUSES (expr), diff --git a/gcc/omp-builtins.def b/gcc/omp-builtins.def index 64531aa773f6..d257278b9e5d 100644 --- a/gcc/omp-builtins.def +++ b/gcc/omp-builtins.def @@ -93,6 +93,9 @@ DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TASKWAIT, "GOMP_taskwait", BT_FN_VOID, ATTR_NOTHROW_LEAF_LIST) DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TASKWAIT_DEPEND, "GOMP_taskwait_depend", BT_FN_VOID_PTR, ATTR_NOTHROW_LEAF_LIST) +DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT, + "GOMP_taskwait_depend_nowait", + BT_FN_VOID_PTR, ATTR_NOTHROW_LEAF_LIST) DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TASKYIELD, "GOMP_taskyield", BT_FN_VOID, ATTR_NOTHROW_LEAF_LIST) DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TASKGROUP_START, "GOMP_taskgroup_start", diff --git a/gcc/omp-expand.cc b/gcc/omp-expand.cc index f228210cc601..b1af4ce37481 100644 --- a/gcc/omp-expand.cc +++ b/gcc/omp-expand.cc @@ -920,10 +920,12 @@ expand_taskwait_call (basic_block bb, gomp_task *entry_stmt) depend = OMP_CLAUSE_DECL (depend); + bool nowait = omp_find_clause (clauses, OMP_CLAUSE_NOWAIT) != NULL_TREE; gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb); - tree t - = build_call_expr (builtin_decl_explicit (BUILT_IN_GOMP_TASKWAIT_DEPEND), - 1, depend); + enum built_in_function f = (nowait + ? BUILT_IN_GOMP_TASKWAIT_DEPEND_NOWAIT + : BUILT_IN_GOMP_TASKWAIT_DEPEND); + tree t = build_call_expr (builtin_decl_explicit (f), 1, depend); force_gimple_operand_gsi (&gsi, t, true, NULL_TREE, false, GSI_CONTINUE_LINKING); diff --git a/gcc/testsuite/ChangeLog.omp b/gcc/testsuite/ChangeLog.omp index cf436d4ccf9e..6523bed1dd54 100644 --- a/gcc/testsuite/ChangeLog.omp +++ b/gcc/testsuite/ChangeLog.omp @@ -1,3 +1,11 @@ +2022-07-05 Tobias Burnus + + Backport from mainline: + 2022-05-24 Jakub Jelinek + + PR c/105378 + * c-c++-common/gomp/taskwait-depend-nowait-1.c: New test. + 2022-07-05 Tobias Burnus Backport from mainline: diff --git a/gcc/testsuite/c-c++-common/gomp/taskwait-depend-nowait-1.c b/gcc/testsuite/c-c++-common/gomp/taskwait-depend-nowait-1.c new file mode 100644 index 000000000000..54df0235bdeb --- /dev/null +++ b/gcc/testsuite/c-c++-common/gomp/taskwait-depend-nowait-1.c @@ -0,0 +1,17 @@ +void +foo (int *p) +{ + #pragma omp taskwait depend(iterator(i = 0:16) , in : p[i]) nowait depend(out : p[32]) +} + +void +bar (int *p) +{ + #pragma omp taskwait depend(mutexinoutset : p[0]) nowait /* { dg-error "'mutexinoutset' kind in 'depend' clause on a 'taskwait' construct" } */ +} + +void +baz (void) +{ + #pragma omp taskwait nowait /* { dg-error "'taskwait' construct with 'nowait' clause but no 'depend' clauses" } */ +} diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp index 2888a8c1f6ef..e1c16cb8f6b7 100644 --- a/libgomp/ChangeLog.omp +++ b/libgomp/ChangeLog.omp @@ -1,3 +1,20 @@ +2022-07-05 Tobias Burnus + + Backport from mainline: + 2022-05-24 Jakub Jelinek + + PR c/105378 + * libgomp_g.h (GOMP_taskwait_depend_nowait): Declare. + * libgomp.map (GOMP_taskwait_depend_nowait): Export at GOMP_5.1.1. + * task.c (empty_task): New function. + (gomp_task_run_post_handle_depend_hash): Declare earlier. + (gomp_task_run_post_handle_depend): Declare. + (GOMP_task): Optimize fn == empty_task if there is nothing to wait + for. + (gomp_task_run_post_handle_dependers): Optimize task->fn == empty_task. + (GOMP_taskwait_depend_nowait): New function. + * testsuite/libgomp.c-c++-common/taskwait-depend-nowait-1.c: New test. + 2022-07-05 Tobias Burnus Backport from mainline: diff --git a/libgomp/libgomp.map b/libgomp/libgomp.map index b0815e8f8b48..5af5c2d8929e 100644 --- a/libgomp/libgomp.map +++ b/libgomp/libgomp.map @@ -413,6 +413,7 @@ GOMP_5.1 { GOMP_5.1.1 { global: + GOMP_taskwait_depend_nowait; GOMP_enable_pinned_mode; } GOMP_5.1; diff --git a/libgomp/libgomp_g.h b/libgomp/libgomp_g.h index a8e29c576c4c..ece1f97a61f3 100644 --- a/libgomp/libgomp_g.h +++ b/libgomp/libgomp_g.h @@ -305,6 +305,7 @@ extern void GOMP_taskloop_ull (void (*) (void *), void *, unsigned long long); extern void GOMP_taskwait (void); extern void GOMP_taskwait_depend (void **); +extern void GOMP_taskwait_depend_nowait (void **); extern void GOMP_taskyield (void); extern void GOMP_taskgroup_start (void); extern void GOMP_taskgroup_end (void); diff --git a/libgomp/task.c b/libgomp/task.c index 6b11a8f02efe..7925e5873c41 100644 --- a/libgomp/task.c +++ b/libgomp/task.c @@ -460,6 +460,17 @@ gomp_task_handle_depend (struct gomp_task *task, struct gomp_task *parent, } } +/* Body of empty task like taskwait nowait depend. */ + +static void +empty_task (void *data __attribute__((unused))) +{ +} + +static void gomp_task_run_post_handle_depend_hash (struct gomp_task *); +static inline size_t gomp_task_run_post_handle_depend (struct gomp_task *, + struct gomp_team *); + /* Called when encountering an explicit task directive. If IF_CLAUSE is false, then we must not delay in executing the task. If UNTIED is true, then the task may be executed by any member of the team. @@ -681,6 +692,18 @@ GOMP_task (void (*fn) (void *), void *data, void (*cpyfn) (void *, void *), gomp_mutex_unlock (&team->task_lock); return; } + /* Check for taskwait nowait depend which doesn't need to wait for + anything. */ + if (__builtin_expect (fn == empty_task, 0)) + { + if (taskgroup) + taskgroup->num_children--; + gomp_task_run_post_handle_depend_hash (task); + gomp_mutex_unlock (&team->task_lock); + gomp_finish_task (task); + free (task); + return; + } } priority_queue_insert (PQ_CHILDREN, &parent->children_queue, @@ -839,8 +862,6 @@ GOMP_PLUGIN_target_task_completion (void *data) gomp_mutex_unlock (&team->task_lock); } -static void gomp_task_run_post_handle_depend_hash (struct gomp_task *); - /* Called for nowait target tasks. */ bool @@ -1357,6 +1378,18 @@ gomp_task_run_post_handle_dependers (struct gomp_task *child_task, continue; struct gomp_taskgroup *taskgroup = task->taskgroup; + if (__builtin_expect (task->fn == empty_task, 0)) + { + if (!parent) + task->parent = NULL; + if (gomp_task_run_post_handle_depend (task, team)) + ++ret; + if (taskgroup) + taskgroup->num_children--; + gomp_finish_task (task); + free (task); + continue; + } if (parent) { priority_queue_insert (PQ_CHILDREN, &parent->children_queue, @@ -1832,6 +1865,16 @@ GOMP_taskwait_depend (void **depend) gomp_task_maybe_wait_for_dependencies (depend); } +/* Called when encountering a taskwait directive with nowait and depend + clause(s). Create a possibly deferred task construct with empty body. */ + +void +GOMP_taskwait_depend_nowait (void **depend) +{ + ialias_call (GOMP_task) (empty_task, "", NULL, 0, 1, true, + GOMP_TASK_FLAG_DEPEND, depend, 0, NULL); +} + /* An undeferred task is about to run. Wait for all tasks that this undeferred task depends on. diff --git a/libgomp/testsuite/libgomp.c-c++-common/taskwait-depend-nowait-1.c b/libgomp/testsuite/libgomp.c-c++-common/taskwait-depend-nowait-1.c new file mode 100644 index 000000000000..3d1519ee70a5 --- /dev/null +++ b/libgomp/testsuite/libgomp.c-c++-common/taskwait-depend-nowait-1.c @@ -0,0 +1,39 @@ +#ifdef __cplusplus +extern "C" +#endif +void abort (void); + +int +main () +{ + int a[64], b = 1; + #pragma omp parallel num_threads (4) + #pragma omp single + { + int i; + #pragma omp taskwait depend(in: a) nowait + #pragma omp taskwait depend(in: a) nowait + #pragma omp taskwait + #pragma omp taskgroup + { + #pragma omp taskwait depend(in: a) nowait + #pragma omp taskwait depend(in: a) nowait + } + for (i = 0; i < 64; ++i) + #pragma omp task depend(in: a) shared(a) + a[i] = i; + #pragma omp taskwait depend(inout: a) nowait + for (i = 0; i < 64; ++i) + #pragma omp task depend(inoutset: a) shared(a) + if (a[i] != i) + abort (); + else + a[i] = 2 * i + 1; + #pragma omp taskwait nowait depend(out: a) depend(in: b) + #pragma omp taskwait depend(inout: b) + for (i = 0; i < 64; ++i) + if (a[i] != 2 * i + 1) + abort (); + } + return 0; +}