V8 API Reference, 7.2.502.16 (for Deno 0.2.4)
builtins-typed-array.cc
1 // Copyright 2016 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/builtins/builtins-utils-inl.h"
6 #include "src/builtins/builtins.h"
7 #include "src/counters.h"
8 #include "src/elements.h"
9 #include "src/objects-inl.h"
10 #include "src/objects/js-array-buffer-inl.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 // -----------------------------------------------------------------------------
16 // ES6 section 22.2 TypedArray Objects
17 
18 // ES6 section 22.2.3.1 get %TypedArray%.prototype.buffer
19 BUILTIN(TypedArrayPrototypeBuffer) {
20  HandleScope scope(isolate);
21  CHECK_RECEIVER(JSTypedArray, typed_array,
22  "get %TypedArray%.prototype.buffer");
23  return *typed_array->GetBuffer();
24 }
25 
26 namespace {
27 
28 int64_t CapRelativeIndex(Handle<Object> num, int64_t minimum, int64_t maximum) {
29  int64_t relative;
30  if (V8_LIKELY(num->IsSmi())) {
31  relative = Smi::ToInt(*num);
32  } else {
33  DCHECK(num->IsHeapNumber());
34  double fp = HeapNumber::cast(*num)->value();
35  if (V8_UNLIKELY(!std::isfinite(fp))) {
36  // +Infinity / -Infinity
37  DCHECK(!std::isnan(fp));
38  return fp < 0 ? minimum : maximum;
39  }
40  relative = static_cast<int64_t>(fp);
41  }
42  return relative < 0 ? std::max<int64_t>(relative + maximum, minimum)
43  : std::min<int64_t>(relative, maximum);
44 }
45 
46 } // namespace
47 
48 BUILTIN(TypedArrayPrototypeCopyWithin) {
49  HandleScope scope(isolate);
50 
51  Handle<JSTypedArray> array;
52  const char* method = "%TypedArray%.prototype.copyWithin";
53  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
54  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
55 
56  int64_t len = array->length_value();
57  int64_t to = 0;
58  int64_t from = 0;
59  int64_t final = len;
60 
61  if (V8_LIKELY(args.length() > 1)) {
62  Handle<Object> num;
63  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
64  isolate, num, Object::ToInteger(isolate, args.at<Object>(1)));
65  to = CapRelativeIndex(num, 0, len);
66 
67  if (args.length() > 2) {
68  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
69  isolate, num, Object::ToInteger(isolate, args.at<Object>(2)));
70  from = CapRelativeIndex(num, 0, len);
71 
72  Handle<Object> end = args.atOrUndefined(isolate, 3);
73  if (!end->IsUndefined(isolate)) {
74  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, num,
75  Object::ToInteger(isolate, end));
76  final = CapRelativeIndex(num, 0, len);
77  }
78  }
79  }
80 
81  int64_t count = std::min<int64_t>(final - from, len - to);
82  if (count <= 0) return *array;
83 
84  // TypedArray buffer may have been transferred/detached during parameter
85  // processing above. Return early in this case, to prevent potential UAF error
86  // TODO(caitp): throw here, as though the full algorithm were performed (the
87  // throw would have come from ecma262/#sec-integerindexedelementget)
88  // (see )
89  if (V8_UNLIKELY(array->WasNeutered())) return *array;
90 
91  // Ensure processed indexes are within array bounds
92  DCHECK_GE(from, 0);
93  DCHECK_LT(from, len);
94  DCHECK_GE(to, 0);
95  DCHECK_LT(to, len);
96  DCHECK_GE(len - count, 0);
97 
98  Handle<FixedTypedArrayBase> elements(
99  FixedTypedArrayBase::cast(array->elements()), isolate);
100  size_t element_size = array->element_size();
101  to = to * element_size;
102  from = from * element_size;
103  count = count * element_size;
104 
105  uint8_t* data = static_cast<uint8_t*>(elements->DataPtr());
106  std::memmove(data + to, data + from, count);
107 
108  return *array;
109 }
110 
111 BUILTIN(TypedArrayPrototypeFill) {
112  HandleScope scope(isolate);
113 
114  Handle<JSTypedArray> array;
115  const char* method = "%TypedArray%.prototype.fill";
116  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
117  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
118  ElementsKind kind = array->GetElementsKind();
119 
120  Handle<Object> obj_value = args.atOrUndefined(isolate, 1);
121  if (kind == BIGINT64_ELEMENTS || kind == BIGUINT64_ELEMENTS) {
122  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, obj_value,
123  BigInt::FromObject(isolate, obj_value));
124  } else {
125  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, obj_value,
126  Object::ToNumber(isolate, obj_value));
127  }
128 
129  int64_t len = array->length_value();
130  int64_t start = 0;
131  int64_t end = len;
132 
133  if (args.length() > 2) {
134  Handle<Object> num = args.atOrUndefined(isolate, 2);
135  if (!num->IsUndefined(isolate)) {
136  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
137  isolate, num, Object::ToInteger(isolate, num));
138  start = CapRelativeIndex(num, 0, len);
139 
140  num = args.atOrUndefined(isolate, 3);
141  if (!num->IsUndefined(isolate)) {
142  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
143  isolate, num, Object::ToInteger(isolate, num));
144  end = CapRelativeIndex(num, 0, len);
145  }
146  }
147  }
148 
149  int64_t count = end - start;
150  if (count <= 0) return *array;
151 
152  if (V8_UNLIKELY(array->WasNeutered())) return *array;
153 
154  // Ensure processed indexes are within array bounds
155  DCHECK_GE(start, 0);
156  DCHECK_LT(start, len);
157  DCHECK_GE(end, 0);
158  DCHECK_LE(end, len);
159  DCHECK_LE(count, len);
160 
161  return ElementsAccessor::ForKind(kind)->Fill(array, obj_value,
162  static_cast<uint32_t>(start),
163  static_cast<uint32_t>(end));
164 }
165 
166 BUILTIN(TypedArrayPrototypeIncludes) {
167  HandleScope scope(isolate);
168 
169  Handle<JSTypedArray> array;
170  const char* method = "%TypedArray%.prototype.includes";
171  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
172  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
173 
174  if (args.length() < 2) return ReadOnlyRoots(isolate).false_value();
175 
176  int64_t len = array->length_value();
177  if (len == 0) return ReadOnlyRoots(isolate).false_value();
178 
179  int64_t index = 0;
180  if (args.length() > 2) {
181  Handle<Object> num;
182  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
183  isolate, num, Object::ToInteger(isolate, args.at<Object>(2)));
184  index = CapRelativeIndex(num, 0, len);
185  }
186 
187  // TODO(cwhan.tunz): throw. See the above comment in CopyWithin.
188  if (V8_UNLIKELY(array->WasNeutered()))
189  return ReadOnlyRoots(isolate).false_value();
190 
191  Handle<Object> search_element = args.atOrUndefined(isolate, 1);
192  ElementsAccessor* elements = array->GetElementsAccessor();
193  Maybe<bool> result = elements->IncludesValue(isolate, array, search_element,
194  static_cast<uint32_t>(index),
195  static_cast<uint32_t>(len));
196  MAYBE_RETURN(result, ReadOnlyRoots(isolate).exception());
197  return *isolate->factory()->ToBoolean(result.FromJust());
198 }
199 
200 BUILTIN(TypedArrayPrototypeIndexOf) {
201  HandleScope scope(isolate);
202 
203  Handle<JSTypedArray> array;
204  const char* method = "%TypedArray%.prototype.indexOf";
205  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
206  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
207 
208  int64_t len = array->length_value();
209  if (len == 0) return Smi::FromInt(-1);
210 
211  int64_t index = 0;
212  if (args.length() > 2) {
213  Handle<Object> num;
214  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
215  isolate, num, Object::ToInteger(isolate, args.at<Object>(2)));
216  index = CapRelativeIndex(num, 0, len);
217  }
218 
219  // TODO(cwhan.tunz): throw. See the above comment in CopyWithin.
220  if (V8_UNLIKELY(array->WasNeutered())) return Smi::FromInt(-1);
221 
222  Handle<Object> search_element = args.atOrUndefined(isolate, 1);
223  ElementsAccessor* elements = array->GetElementsAccessor();
224  Maybe<int64_t> result = elements->IndexOfValue(isolate, array, search_element,
225  static_cast<uint32_t>(index),
226  static_cast<uint32_t>(len));
227  MAYBE_RETURN(result, ReadOnlyRoots(isolate).exception());
228  return *isolate->factory()->NewNumberFromInt64(result.FromJust());
229 }
230 
231 BUILTIN(TypedArrayPrototypeLastIndexOf) {
232  HandleScope scope(isolate);
233 
234  Handle<JSTypedArray> array;
235  const char* method = "%TypedArray%.prototype.lastIndexOf";
236  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
237  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
238 
239  int64_t len = array->length_value();
240  if (len == 0) return Smi::FromInt(-1);
241 
242  int64_t index = len - 1;
243  if (args.length() > 2) {
244  Handle<Object> num;
245  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
246  isolate, num, Object::ToInteger(isolate, args.at<Object>(2)));
247  // Set a negative value (-1) for returning -1 if num is negative and
248  // len + num is still negative. Upper bound is len - 1.
249  index = std::min<int64_t>(CapRelativeIndex(num, -1, len), len - 1);
250  }
251 
252  if (index < 0) return Smi::FromInt(-1);
253 
254  // TODO(cwhan.tunz): throw. See the above comment in CopyWithin.
255  if (V8_UNLIKELY(array->WasNeutered())) return Smi::FromInt(-1);
256 
257  Handle<Object> search_element = args.atOrUndefined(isolate, 1);
258  ElementsAccessor* elements = array->GetElementsAccessor();
259  Maybe<int64_t> result = elements->LastIndexOfValue(
260  array, search_element, static_cast<uint32_t>(index));
261  MAYBE_RETURN(result, ReadOnlyRoots(isolate).exception());
262  return *isolate->factory()->NewNumberFromInt64(result.FromJust());
263 }
264 
265 BUILTIN(TypedArrayPrototypeReverse) {
266  HandleScope scope(isolate);
267 
268  Handle<JSTypedArray> array;
269  const char* method = "%TypedArray%.prototype.reverse";
270  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
271  isolate, array, JSTypedArray::Validate(isolate, args.receiver(), method));
272 
273  ElementsAccessor* elements = array->GetElementsAccessor();
274  elements->Reverse(*array);
275  return *array;
276 }
277 
278 } // namespace internal
279 } // namespace v8
int64_t
v8
Definition: libplatform.h:13