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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/base/macros.h"
#include "src/base/platform/mutex.h"
#include "src/base/platform/time.h"
#include "src/builtins/builtins-utils.h"
#include "src/builtins/builtins.h"
#include "src/code-factory.h"
#include "src/conversions-inl.h"
#include "src/counters.h"
#include "src/factory.h"
#include "src/futex-emulation.h"
#include "src/globals.h"
#include "src/objects-inl.h"
namespace v8 {
namespace internal {
// See builtins-arraybuffer.cc for implementations of
// SharedArrayBuffer.prototye.byteLength and SharedArrayBuffer.prototype.slice
inline bool AtomicIsLockFree(uint32_t size) {
return size == 1 || size == 2 || size == 4;
}
// ES #sec-atomics.islockfree
BUILTIN(AtomicsIsLockFree) {
HandleScope scope(isolate);
Handle<Object> size = args.atOrUndefined(isolate, 1);
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, size, Object::ToNumber(size));
return *isolate->factory()->ToBoolean(AtomicIsLockFree(size->Number()));
}
// ES #sec-validatesharedintegertypedarray
MUST_USE_RESULT MaybeHandle<JSTypedArray> ValidateSharedIntegerTypedArray(
Isolate* isolate, Handle<Object> object, bool only_int32 = false) {
if (object->IsJSTypedArray()) {
Handle<JSTypedArray> typed_array = Handle<JSTypedArray>::cast(object);
if (typed_array->GetBuffer()->is_shared()) {
if (only_int32) {
if (typed_array->type() == kExternalInt32Array) return typed_array;
} else {
if (typed_array->type() != kExternalFloat32Array &&
typed_array->type() != kExternalFloat64Array &&
typed_array->type() != kExternalUint8ClampedArray)
return typed_array;
}
}
}
THROW_NEW_ERROR(
isolate,
NewTypeError(only_int32 ? MessageTemplate::kNotInt32SharedTypedArray
: MessageTemplate::kNotIntegerSharedTypedArray,
object),
JSTypedArray);
}
// ES #sec-validateatomicaccess
// ValidateAtomicAccess( typedArray, requestIndex )
MUST_USE_RESULT Maybe<size_t> ValidateAtomicAccess(
Isolate* isolate, Handle<JSTypedArray> typed_array,
Handle<Object> request_index) {
Handle<Object> access_index_obj;
ASSIGN_RETURN_ON_EXCEPTION_VALUE(
isolate, access_index_obj,
Object::ToIndex(isolate, request_index,
MessageTemplate::kInvalidAtomicAccessIndex),
Nothing<size_t>());
size_t access_index;
if (!TryNumberToSize(*access_index_obj, &access_index) ||
access_index >= typed_array->length_value()) {
isolate->Throw(*isolate->factory()->NewRangeError(
MessageTemplate::kInvalidAtomicAccessIndex));
return Nothing<size_t>();
}
return Just<size_t>(access_index);
}
// ES #sec-atomics.wake
// Atomics.wake( typedArray, index, count )
BUILTIN(AtomicsWake) {
HandleScope scope(isolate);
Handle<Object> array = args.atOrUndefined(isolate, 1);
Handle<Object> index = args.atOrUndefined(isolate, 2);
Handle<Object> count = args.atOrUndefined(isolate, 3);
Handle<JSTypedArray> sta;
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
isolate, sta, ValidateSharedIntegerTypedArray(isolate, array, true));
Maybe<size_t> maybe_index = ValidateAtomicAccess(isolate, sta, index);
if (maybe_index.IsNothing()) return isolate->heap()->exception();
size_t i = maybe_index.FromJust();
uint32_t c;
if (count->IsUndefined(isolate)) {
c = kMaxUInt32;
} else {
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, count,
Object::ToInteger(isolate, count));
double count_double = count->Number();
if (count_double < 0)
count_double = 0;
else if (count_double > kMaxUInt32)
count_double = kMaxUInt32;
c = static_cast<uint32_t>(count_double);
}
Handle<JSArrayBuffer> array_buffer = sta->GetBuffer();
size_t addr = (i << 2) + NumberToSize(sta->byte_offset());
return FutexEmulation::Wake(isolate, array_buffer, addr, c);
}
// ES #sec-atomics.wait
// Atomics.wait( typedArray, index, value, timeout )
BUILTIN(AtomicsWait) {
HandleScope scope(isolate);
Handle<Object> array = args.atOrUndefined(isolate, 1);
Handle<Object> index = args.atOrUndefined(isolate, 2);
Handle<Object> value = args.atOrUndefined(isolate, 3);
Handle<Object> timeout = args.atOrUndefined(isolate, 4);
Handle<JSTypedArray> sta;
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
isolate, sta, ValidateSharedIntegerTypedArray(isolate, array, true));
Maybe<size_t> maybe_index = ValidateAtomicAccess(isolate, sta, index);
if (maybe_index.IsNothing()) return isolate->heap()->exception();
size_t i = maybe_index.FromJust();
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value,
Object::ToInt32(isolate, value));
int32_t value_int32 = NumberToInt32(*value);
double timeout_number;
if (timeout->IsUndefined(isolate)) {
timeout_number = isolate->heap()->infinity_value()->Number();
} else {
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, timeout,
Object::ToNumber(timeout));
timeout_number = timeout->Number();
if (std::isnan(timeout_number))
timeout_number = isolate->heap()->infinity_value()->Number();
else if (timeout_number < 0)
timeout_number = 0;
}
if (!isolate->allow_atomics_wait()) {
THROW_NEW_ERROR_RETURN_FAILURE(
isolate, NewTypeError(MessageTemplate::kAtomicsWaitNotAllowed));
}
Handle<JSArrayBuffer> array_buffer = sta->GetBuffer();
size_t addr = (i << 2) + NumberToSize(sta->byte_offset());
return FutexEmulation::Wait(isolate, array_buffer, addr, value_int32,
timeout_number);
}
} // namespace internal
} // namespace v8
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