1//===-------- Tasking.cpp - NVPTX OpenMP tasks support ------------ C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Task implementation support.
10//
11// TODO: We should not allocate and execute the task in two steps. A new API is
12// needed for that though.
13//
14//===----------------------------------------------------------------------===//
15
16#include "Interface.h"
17#include "State.h"
18#include "Types.h"
19#include "Utils.h"
20
21using namespace ompx;
22
23#pragma omp begin declare target device_type(nohost)
24
25extern "C" {
26
27TaskDescriptorTy *__kmpc_omp_task_alloc(IdentTy *, int32_t, int32_t,
28 size_t TaskSizeInclPrivateValues,
29 size_t SharedValuesSize,
30 TaskFnTy TaskFn) {
31 auto TaskSizeInclPrivateValuesPadded =
32 utils::roundUp(TaskSizeInclPrivateValues, uint64_t(sizeof(void *)));
33 auto TaskSizeTotal = TaskSizeInclPrivateValuesPadded + SharedValuesSize;
34 TaskDescriptorTy *TaskDescriptor = (TaskDescriptorTy *)memory::allocGlobal(
35 TaskSizeTotal, "explicit task descriptor");
36 TaskDescriptor->Payload =
37 utils::advance(TaskDescriptor, TaskSizeInclPrivateValuesPadded);
38 TaskDescriptor->TaskFn = TaskFn;
39
40 return TaskDescriptor;
41}
42
43int32_t __kmpc_omp_task(IdentTy *Loc, uint32_t TId,
44 TaskDescriptorTy *TaskDescriptor) {
45 return __kmpc_omp_task_with_deps(Loc, TId, TaskDescriptor, 0, 0, 0, 0);
46}
47
48int32_t __kmpc_omp_task_with_deps(IdentTy *Loc, uint32_t TId,
49 TaskDescriptorTy *TaskDescriptor, int32_t,
50 void *, int32_t, void *) {
51 state::DateEnvironmentRAII DERAII(Loc);
52
53 TaskDescriptor->TaskFn(0, TaskDescriptor);
54
55 memory::freeGlobal(TaskDescriptor, "explicit task descriptor");
56 return 0;
57}
58
59void __kmpc_omp_task_begin_if0(IdentTy *Loc, uint32_t TId,
60 TaskDescriptorTy *TaskDescriptor) {
61 state::enterDataEnvironment(Loc);
62}
63
64void __kmpc_omp_task_complete_if0(IdentTy *Loc, uint32_t TId,
65 TaskDescriptorTy *TaskDescriptor) {
66 state::exitDataEnvironment();
67
68 memory::freeGlobal(TaskDescriptor, "explicit task descriptor");
69}
70
71void __kmpc_omp_wait_deps(IdentTy *Loc, uint32_t TId, int32_t, void *, int32_t,
72 void *) {}
73
74void __kmpc_taskgroup(IdentTy *Loc, uint32_t TId) {}
75
76void __kmpc_end_taskgroup(IdentTy *Loc, uint32_t TId) {}
77
78int32_t __kmpc_omp_taskyield(IdentTy *Loc, uint32_t TId, int) { return 0; }
79
80int32_t __kmpc_omp_taskwait(IdentTy *Loc, uint32_t TId) { return 0; }
81
82void __kmpc_taskloop(IdentTy *Loc, uint32_t TId,
83 TaskDescriptorTy *TaskDescriptor, int,
84 uint64_t *LowerBound, uint64_t *UpperBound, int64_t, int,
85 int32_t, uint64_t, void *) {
86 // Skip task entirely if empty iteration space.
87 if (*LowerBound > *UpperBound)
88 return;
89
90 // The compiler has already stored lb and ub in the TaskDescriptorTy structure
91 // as we are using a single task to execute the entire loop, we can leave
92 // the initial task_t untouched
93 __kmpc_omp_task_with_deps(Loc, TId, TaskDescriptor, 0, 0, 0, 0);
94}
95
96int omp_in_final(void) {
97 // treat all tasks as final... Specs may expect runtime to keep
98 // track more precisely if a task was actively set by users... This
99 // is not explicitly specified; will treat as if runtime can
100 // actively decide to put a non-final task into a final one.
101 return 1;
102}
103
104int omp_get_max_task_priority(void) { return 0; }
105}
106
107#pragma omp end declare target
108

source code of offload/DeviceRTL/src/Tasking.cpp