1//===--------- Misc.cpp - OpenMP device misc interfaces ----------- 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//
10//===----------------------------------------------------------------------===//
11
12#include "Allocator.h"
13#include "Configuration.h"
14#include "DeviceTypes.h"
15#include "Shared/RPCOpcodes.h"
16#include "shared/rpc.h"
17
18#include "Debug.h"
19
20namespace ompx {
21namespace impl {
22
23/// Lookup a device-side function using a host pointer /p HstPtr using the table
24/// provided by the device plugin. The table is an ordered pair of host and
25/// device pointers sorted on the value of the host pointer.
26void *indirectCallLookup(void *HstPtr) {
27 if (!HstPtr)
28 return nullptr;
29
30 struct IndirectCallTable {
31 void *HstPtr;
32 void *DevPtr;
33 };
34 IndirectCallTable *Table =
35 reinterpret_cast<IndirectCallTable *>(config::getIndirectCallTablePtr());
36 uint64_t TableSize = config::getIndirectCallTableSize();
37
38 // If the table is empty we assume this is device pointer.
39 if (!Table || !TableSize)
40 return HstPtr;
41
42 uint32_t Left = 0;
43 uint32_t Right = TableSize;
44
45 // If the pointer is definitely not contained in the table we exit early.
46 if (HstPtr < Table[Left].HstPtr || HstPtr > Table[Right - 1].HstPtr)
47 return HstPtr;
48
49 while (Left != Right) {
50 uint32_t Current = Left + (Right - Left) / 2;
51 if (Table[Current].HstPtr == HstPtr)
52 return Table[Current].DevPtr;
53
54 if (HstPtr < Table[Current].HstPtr)
55 Right = Current;
56 else
57 Left = Current;
58 }
59
60 // If we searched the whole table and found nothing this is a device pointer.
61 return HstPtr;
62}
63
64/// The openmp client instance used to communicate with the server.
65[[gnu::visibility("protected"),
66 gnu::weak]] rpc::Client Client asm("__llvm_rpc_client");
67
68} // namespace impl
69} // namespace ompx
70
71/// Interfaces
72///
73///{
74
75extern "C" {
76int32_t __kmpc_cancellationpoint(IdentTy *, int32_t, int32_t) { return 0; }
77
78int32_t __kmpc_cancel(IdentTy *, int32_t, int32_t) { return 0; }
79
80double omp_get_wtick(void) {
81 // The number of ticks per second for the AMDGPU clock varies by card and can
82 // only be retrieved by querying the driver. We rely on the device environment
83 // to inform us what the proper frequency is. NVPTX uses a nanosecond
84 // resolution, we could omit the global read but this makes it consistent.
85 return 1.0 / ompx::config::getClockFrequency();
86}
87
88double omp_get_wtime(void) {
89 return static_cast<double>(__builtin_readsteadycounter()) * omp_get_wtick();
90}
91
92void *__llvm_omp_indirect_call_lookup(void *HstPtr) {
93 return ompx::impl::indirectCallLookup(HstPtr);
94}
95
96void *omp_alloc(size_t size, omp_allocator_handle_t allocator) {
97 switch (allocator) {
98 case omp_default_mem_alloc:
99 case omp_large_cap_mem_alloc:
100 case omp_const_mem_alloc:
101 case omp_high_bw_mem_alloc:
102 case omp_low_lat_mem_alloc:
103 return malloc(size: size);
104 default:
105 return nullptr;
106 }
107}
108
109void omp_free(void *ptr, omp_allocator_handle_t allocator) {
110 switch (allocator) {
111 case omp_default_mem_alloc:
112 case omp_large_cap_mem_alloc:
113 case omp_const_mem_alloc:
114 case omp_high_bw_mem_alloc:
115 case omp_low_lat_mem_alloc:
116 free(ptr: ptr);
117 case omp_null_allocator:
118 default:
119 return;
120 }
121}
122
123unsigned long long __llvm_omp_host_call(void *fn, void *data, size_t size) {
124 rpc::Client::Port Port = ompx::impl::Client.open<OFFLOAD_HOST_CALL>();
125 Port.send_n(data, size);
126 Port.send([=](rpc::Buffer *buffer, uint32_t) {
127 buffer->data[0] = reinterpret_cast<uintptr_t>(fn);
128 });
129 unsigned long long Ret;
130 Port.recv([&](rpc::Buffer *Buffer, uint32_t) {
131 Ret = static_cast<unsigned long long>(Buffer->data[0]);
132 });
133 Port.close();
134 return Ret;
135}
136}
137
138///}
139

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