Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 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" |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 8 | #include "src/factory.h" |
| 9 | #include "src/isolate-inl.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 10 | #include "src/objects-inl.h" |
| 11 | |
| 12 | namespace v8 { |
| 13 | namespace internal { |
| 14 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 15 | namespace { |
| 16 | |
| 17 | // Returns either a FixedArray or, if the given {receiver} has an enum cache |
| 18 | // that contains all enumerable properties of the {receiver} and its prototypes |
| 19 | // have none, the map of the {receiver}. This is used to speed up the check for |
| 20 | // deletions during a for-in. |
| 21 | MaybeHandle<HeapObject> Enumerate(Handle<JSReceiver> receiver) { |
| 22 | Isolate* const isolate = receiver->GetIsolate(); |
| 23 | // Test if we have an enum cache for {receiver}. |
| 24 | if (!receiver->IsSimpleEnum()) { |
| 25 | Handle<FixedArray> keys; |
| 26 | ASSIGN_RETURN_ON_EXCEPTION( |
| 27 | isolate, keys, |
| 28 | JSReceiver::GetKeys(receiver, INCLUDE_PROTOS, ENUMERABLE_STRINGS), |
| 29 | HeapObject); |
| 30 | // Test again, since cache may have been built by GetKeys() calls above. |
| 31 | if (!receiver->IsSimpleEnum()) return keys; |
| 32 | } |
| 33 | return handle(receiver->map(), isolate); |
| 34 | } |
| 35 | |
| 36 | |
| 37 | MaybeHandle<Object> Filter(Handle<JSReceiver> receiver, Handle<Object> key) { |
| 38 | Isolate* const isolate = receiver->GetIsolate(); |
| 39 | // TODO(turbofan): Fast case for array indices. |
| 40 | Handle<Name> name; |
| 41 | ASSIGN_RETURN_ON_EXCEPTION(isolate, name, Object::ToName(isolate, key), |
| 42 | Object); |
| 43 | Maybe<bool> result = JSReceiver::HasProperty(receiver, name); |
| 44 | MAYBE_RETURN_NULL(result); |
| 45 | if (result.FromJust()) return name; |
| 46 | return isolate->factory()->undefined_value(); |
| 47 | } |
| 48 | |
| 49 | } // namespace |
| 50 | |
| 51 | |
| 52 | RUNTIME_FUNCTION(Runtime_ForInEnumerate) { |
| 53 | HandleScope scope(isolate); |
| 54 | DCHECK_EQ(1, args.length()); |
| 55 | CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0); |
| 56 | Handle<HeapObject> result; |
| 57 | ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Enumerate(receiver)); |
| 58 | return *result; |
| 59 | } |
| 60 | |
| 61 | |
| 62 | RUNTIME_FUNCTION_RETURN_TRIPLE(Runtime_ForInPrepare) { |
| 63 | HandleScope scope(isolate); |
| 64 | DCHECK_EQ(1, args.length()); |
| 65 | Handle<JSReceiver> receiver = args.at<JSReceiver>(0); |
| 66 | Handle<Object> cache_type; |
| 67 | if (!Enumerate(receiver).ToHandle(&cache_type)) { |
| 68 | return MakeTriple(isolate->heap()->exception(), nullptr, nullptr); |
| 69 | } |
| 70 | Handle<FixedArray> cache_array; |
| 71 | int cache_length; |
| 72 | if (cache_type->IsMap()) { |
| 73 | Handle<Map> cache_map = Handle<Map>::cast(cache_type); |
| 74 | Handle<DescriptorArray> descriptors(cache_map->instance_descriptors(), |
| 75 | isolate); |
| 76 | cache_length = cache_map->EnumLength(); |
| 77 | if (cache_length && descriptors->HasEnumCache()) { |
| 78 | cache_array = handle(descriptors->GetEnumCache(), isolate); |
| 79 | } else { |
| 80 | cache_array = isolate->factory()->empty_fixed_array(); |
| 81 | cache_length = 0; |
| 82 | } |
| 83 | } else { |
| 84 | cache_array = Handle<FixedArray>::cast(cache_type); |
| 85 | cache_length = cache_array->length(); |
| 86 | cache_type = handle(Smi::FromInt(1), isolate); |
| 87 | } |
| 88 | return MakeTriple(*cache_type, *cache_array, Smi::FromInt(cache_length)); |
| 89 | } |
| 90 | |
| 91 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 92 | RUNTIME_FUNCTION(Runtime_ForInDone) { |
| 93 | SealHandleScope scope(isolate); |
| 94 | DCHECK_EQ(2, args.length()); |
| 95 | CONVERT_SMI_ARG_CHECKED(index, 0); |
| 96 | CONVERT_SMI_ARG_CHECKED(length, 1); |
| 97 | DCHECK_LE(0, index); |
| 98 | DCHECK_LE(index, length); |
| 99 | return isolate->heap()->ToBoolean(index == length); |
| 100 | } |
| 101 | |
| 102 | |
| 103 | RUNTIME_FUNCTION(Runtime_ForInFilter) { |
| 104 | HandleScope scope(isolate); |
| 105 | DCHECK_EQ(2, args.length()); |
| 106 | CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0); |
| 107 | CONVERT_ARG_HANDLE_CHECKED(Object, key, 1); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 108 | Handle<Object> result; |
| 109 | ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Filter(receiver, key)); |
| 110 | return *result; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | |
| 114 | RUNTIME_FUNCTION(Runtime_ForInNext) { |
| 115 | HandleScope scope(isolate); |
| 116 | DCHECK_EQ(4, args.length()); |
| 117 | CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0); |
| 118 | CONVERT_ARG_HANDLE_CHECKED(FixedArray, cache_array, 1); |
| 119 | CONVERT_ARG_HANDLE_CHECKED(Object, cache_type, 2); |
| 120 | CONVERT_SMI_ARG_CHECKED(index, 3); |
| 121 | Handle<Object> key = handle(cache_array->get(index), isolate); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 122 | // Don't need filtering if expected map still matches that of the receiver. |
| 123 | if (receiver->map() == *cache_type) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 124 | return *key; |
| 125 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 126 | Handle<Object> result; |
| 127 | ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Filter(receiver, key)); |
| 128 | return *result; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 129 | } |
| 130 | |
| 131 | |
| 132 | RUNTIME_FUNCTION(Runtime_ForInStep) { |
| 133 | SealHandleScope scope(isolate); |
| 134 | DCHECK_EQ(1, args.length()); |
| 135 | CONVERT_SMI_ARG_CHECKED(index, 0); |
| 136 | DCHECK_LE(0, index); |
| 137 | DCHECK_LT(index, Smi::kMaxValue); |
| 138 | return Smi::FromInt(index + 1); |
| 139 | } |
| 140 | |
| 141 | } // namespace internal |
| 142 | } // namespace v8 |