1 // Copyright 2015 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/runtime/runtime-utils.h"
6
7 #include "src/arguments.h"
8 #include "src/base/platform/time.h"
9 #include "src/conversions-inl.h"
10 #include "src/futex-emulation.h"
11 #include "src/globals.h"
12
13 // Implement Futex API for SharedArrayBuffers as defined in the
14 // SharedArrayBuffer draft spec, found here:
15 // https://github.com/tc39/ecmascript_sharedmem
16
17 namespace v8 {
18 namespace internal {
19
RUNTIME_FUNCTION(Runtime_AtomicsWait)20 RUNTIME_FUNCTION(Runtime_AtomicsWait) {
21 HandleScope scope(isolate);
22 DCHECK_EQ(4, args.length());
23 CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, sta, 0);
24 CONVERT_SIZE_ARG_CHECKED(index, 1);
25 CONVERT_INT32_ARG_CHECKED(value, 2);
26 CONVERT_DOUBLE_ARG_CHECKED(timeout, 3);
27 CHECK(sta->GetBuffer()->is_shared());
28 CHECK_LT(index, NumberToSize(sta->length()));
29 CHECK_EQ(sta->type(), kExternalInt32Array);
30 CHECK(timeout == V8_INFINITY || !std::isnan(timeout));
31
32 if (!isolate->allow_atomics_wait()) {
33 THROW_NEW_ERROR_RETURN_FAILURE(
34 isolate, NewTypeError(MessageTemplate::kAtomicsWaitNotAllowed));
35 }
36
37 Handle<JSArrayBuffer> array_buffer = sta->GetBuffer();
38 size_t addr = (index << 2) + NumberToSize(sta->byte_offset());
39
40 return FutexEmulation::Wait(isolate, array_buffer, addr, value, timeout);
41 }
42
RUNTIME_FUNCTION(Runtime_AtomicsWake)43 RUNTIME_FUNCTION(Runtime_AtomicsWake) {
44 HandleScope scope(isolate);
45 DCHECK_EQ(3, args.length());
46 CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, sta, 0);
47 CONVERT_SIZE_ARG_CHECKED(index, 1);
48 CONVERT_UINT32_ARG_CHECKED(count, 2);
49 CHECK(sta->GetBuffer()->is_shared());
50 CHECK_LT(index, NumberToSize(sta->length()));
51 CHECK_EQ(sta->type(), kExternalInt32Array);
52
53 Handle<JSArrayBuffer> array_buffer = sta->GetBuffer();
54 size_t addr = (index << 2) + NumberToSize(sta->byte_offset());
55
56 return FutexEmulation::Wake(isolate, array_buffer, addr, count);
57 }
58
RUNTIME_FUNCTION(Runtime_AtomicsNumWaitersForTesting)59 RUNTIME_FUNCTION(Runtime_AtomicsNumWaitersForTesting) {
60 HandleScope scope(isolate);
61 DCHECK_EQ(2, args.length());
62 CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, sta, 0);
63 CONVERT_SIZE_ARG_CHECKED(index, 1);
64 CHECK(sta->GetBuffer()->is_shared());
65 CHECK_LT(index, NumberToSize(sta->length()));
66 CHECK_EQ(sta->type(), kExternalInt32Array);
67
68 Handle<JSArrayBuffer> array_buffer = sta->GetBuffer();
69 size_t addr = (index << 2) + NumberToSize(sta->byte_offset());
70
71 return FutexEmulation::NumWaitersForTesting(isolate, array_buffer, addr);
72 }
73
RUNTIME_FUNCTION(Runtime_SetAllowAtomicsWait)74 RUNTIME_FUNCTION(Runtime_SetAllowAtomicsWait) {
75 HandleScope scope(isolate);
76 DCHECK_EQ(1, args.length());
77 CONVERT_BOOLEAN_ARG_CHECKED(set, 0);
78
79 isolate->set_allow_atomics_wait(set);
80 return isolate->heap()->undefined_value();
81 }
82 } // namespace internal
83 } // namespace v8
84