1// Copyright 2018 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/growable-fixed-array-gen.h"
6
7#include "src/compiler/code-assembler.h"
8
9namespace v8 {
10namespace internal {
11
12void GrowableFixedArray::Push(const TNode<Object> value) {
13  const TNode<IntPtrT> length = var_length_.value();
14  const TNode<IntPtrT> capacity = var_capacity_.value();
15
16  Label grow(this), store(this);
17  Branch(IntPtrEqual(capacity, length), &grow, &store);
18
19  BIND(&grow);
20  {
21    var_capacity_ = NewCapacity(capacity);
22    var_array_ = ResizeFixedArray(length, var_capacity_.value());
23
24    Goto(&store);
25  }
26
27  BIND(&store);
28  {
29    const TNode<FixedArray> array = var_array_.value();
30    UnsafeStoreFixedArrayElement(array, length, value);
31
32    var_length_ = IntPtrAdd(length, IntPtrConstant(1));
33  }
34}
35
36TNode<FixedArray> GrowableFixedArray::ToFixedArray() {
37  return ResizeFixedArray(length(), length());
38}
39
40TNode<JSArray> GrowableFixedArray::ToJSArray(const TNode<Context> context) {
41  const ElementsKind kind = PACKED_ELEMENTS;
42
43  const TNode<NativeContext> native_context = LoadNativeContext(context);
44  const TNode<Map> array_map = LoadJSArrayElementsMap(kind, native_context);
45
46  // Shrink to fit if necessary.
47  {
48    Label next(this);
49
50    const TNode<IntPtrT> length = var_length_.value();
51    const TNode<IntPtrT> capacity = var_capacity_.value();
52
53    GotoIf(WordEqual(length, capacity), &next);
54
55    var_array_ = ResizeFixedArray(length, length);
56    var_capacity_ = length;
57    Goto(&next);
58
59    BIND(&next);
60  }
61
62  const TNode<Smi> result_length = SmiTag(length());
63  const TNode<JSArray> result =
64      AllocateJSArray(array_map, var_array_.value(), result_length);
65  return result;
66}
67
68TNode<IntPtrT> GrowableFixedArray::NewCapacity(
69    TNode<IntPtrT> current_capacity) {
70  CSA_DCHECK(this,
71             IntPtrGreaterThanOrEqual(current_capacity, IntPtrConstant(0)));
72
73  // Growth rate is analog to JSObject::NewElementsCapacity:
74  // new_capacity = (current_capacity + (current_capacity >> 1)) + 16.
75
76  const TNode<IntPtrT> new_capacity =
77      IntPtrAdd(IntPtrAdd(current_capacity, WordShr(current_capacity, 1)),
78                IntPtrConstant(16));
79
80  return new_capacity;
81}
82
83TNode<FixedArray> GrowableFixedArray::ResizeFixedArray(
84    const TNode<IntPtrT> element_count, const TNode<IntPtrT> new_capacity) {
85  CSA_DCHECK(this, IntPtrGreaterThanOrEqual(element_count, IntPtrConstant(0)));
86  CSA_DCHECK(this, IntPtrGreaterThanOrEqual(new_capacity, IntPtrConstant(0)));
87  CSA_DCHECK(this, IntPtrGreaterThanOrEqual(new_capacity, element_count));
88
89  const TNode<FixedArray> from_array = var_array_.value();
90
91  CodeStubAssembler::ExtractFixedArrayFlags flags;
92  flags |= CodeStubAssembler::ExtractFixedArrayFlag::kFixedArrays;
93  TNode<FixedArray> to_array = CAST(ExtractFixedArray(
94      from_array, base::Optional<TNode<IntPtrT>>(base::nullopt),
95      base::Optional<TNode<IntPtrT>>(element_count),
96      base::Optional<TNode<IntPtrT>>(new_capacity), flags));
97
98  return to_array;
99}
100
101}  // namespace internal
102}  // namespace v8
103