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1 // Copyright 2008 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
4 // met:
5 //
6 //     * Redistributions of source code must retain the above copyright
7 //       notice, this list of conditions and the following disclaimer.
8 //     * Redistributions in binary form must reproduce the above
9 //       copyright notice, this list of conditions and the following
10 //       disclaimer in the documentation and/or other materials provided
11 //       with the distribution.
12 //     * Neither the name of Google Inc. nor the names of its
13 //       contributors may be used to endorse or promote products derived
14 //       from this software without specific prior written permission.
15 //
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 
28 #include <stdlib.h>
29 
30 #include "v8.h"
31 
32 namespace v8 {
33 namespace internal {
34 
35 
New(size_t size)36 void* Malloced::New(size_t size) {
37   ASSERT(NativeAllocationChecker::allocation_allowed());
38   void* result = malloc(size);
39   if (result == NULL) V8::FatalProcessOutOfMemory("Malloced operator new");
40   return result;
41 }
42 
43 
Delete(void * p)44 void Malloced::Delete(void* p) {
45   free(p);
46 }
47 
48 
FatalProcessOutOfMemory()49 void Malloced::FatalProcessOutOfMemory() {
50   V8::FatalProcessOutOfMemory("Out of memory");
51 }
52 
53 
54 #ifdef DEBUG
55 
56 static void* invalid = static_cast<void*>(NULL);
57 
operator new(size_t size)58 void* Embedded::operator new(size_t size) {
59   UNREACHABLE();
60   return invalid;
61 }
62 
63 
operator delete(void * p)64 void Embedded::operator delete(void* p) {
65   UNREACHABLE();
66 }
67 
68 
operator new(size_t size)69 void* AllStatic::operator new(size_t size) {
70   UNREACHABLE();
71   return invalid;
72 }
73 
74 
operator delete(void * p)75 void AllStatic::operator delete(void* p) {
76   UNREACHABLE();
77 }
78 
79 #endif
80 
81 
StrDup(const char * str)82 char* StrDup(const char* str) {
83   int length = strlen(str);
84   char* result = NewArray<char>(length + 1);
85   memcpy(result, str, length * kCharSize);
86   result[length] = '\0';
87   return result;
88 }
89 
90 
StrNDup(const char * str,size_t n)91 char* StrNDup(const char* str, size_t n) {
92   size_t length = strlen(str);
93   if (n < length) length = n;
94   char* result = NewArray<char>(length + 1);
95   memcpy(result, str, length * kCharSize);
96   result[length] = '\0';
97   return result;
98 }
99 
100 
101 int NativeAllocationChecker::allocation_disallowed_ = 0;
102 
103 
104 PreallocatedStorage PreallocatedStorage::in_use_list_(0);
105 PreallocatedStorage PreallocatedStorage::free_list_(0);
106 bool PreallocatedStorage::preallocated_ = false;
107 
108 
Init(size_t size)109 void PreallocatedStorage::Init(size_t size) {
110   ASSERT(free_list_.next_ == &free_list_);
111   ASSERT(free_list_.previous_ == &free_list_);
112   PreallocatedStorage* free_chunk =
113       reinterpret_cast<PreallocatedStorage*>(new char[size]);
114   free_list_.next_ = free_list_.previous_ = free_chunk;
115   free_chunk->next_ = free_chunk->previous_ = &free_list_;
116   free_chunk->size_ = size - sizeof(PreallocatedStorage);
117   preallocated_ = true;
118 }
119 
120 
New(size_t size)121 void* PreallocatedStorage::New(size_t size) {
122   if (!preallocated_) {
123     return FreeStoreAllocationPolicy::New(size);
124   }
125   ASSERT(free_list_.next_ != &free_list_);
126   ASSERT(free_list_.previous_ != &free_list_);
127   size = (size + kPointerSize - 1) & ~(kPointerSize - 1);
128   // Search for exact fit.
129   for (PreallocatedStorage* storage = free_list_.next_;
130        storage != &free_list_;
131        storage = storage->next_) {
132     if (storage->size_ == size) {
133       storage->Unlink();
134       storage->LinkTo(&in_use_list_);
135       return reinterpret_cast<void*>(storage + 1);
136     }
137   }
138   // Search for first fit.
139   for (PreallocatedStorage* storage = free_list_.next_;
140        storage != &free_list_;
141        storage = storage->next_) {
142     if (storage->size_ >= size + sizeof(PreallocatedStorage)) {
143       storage->Unlink();
144       storage->LinkTo(&in_use_list_);
145       PreallocatedStorage* left_over =
146           reinterpret_cast<PreallocatedStorage*>(
147               reinterpret_cast<char*>(storage + 1) + size);
148       left_over->size_ = storage->size_ - size - sizeof(PreallocatedStorage);
149       ASSERT(size + left_over->size_ + sizeof(PreallocatedStorage) ==
150              storage->size_);
151       storage->size_ = size;
152       left_over->LinkTo(&free_list_);
153       return reinterpret_cast<void*>(storage + 1);
154     }
155   }
156   // Allocation failure.
157   ASSERT(false);
158   return NULL;
159 }
160 
161 
162 // We don't attempt to coalesce.
Delete(void * p)163 void PreallocatedStorage::Delete(void* p) {
164   if (p == NULL) {
165     return;
166   }
167   if (!preallocated_) {
168     FreeStoreAllocationPolicy::Delete(p);
169     return;
170   }
171   PreallocatedStorage* storage = reinterpret_cast<PreallocatedStorage*>(p) - 1;
172   ASSERT(storage->next_->previous_ == storage);
173   ASSERT(storage->previous_->next_ == storage);
174   storage->Unlink();
175   storage->LinkTo(&free_list_);
176 }
177 
178 
LinkTo(PreallocatedStorage * other)179 void PreallocatedStorage::LinkTo(PreallocatedStorage* other) {
180   next_ = other->next_;
181   other->next_->previous_ = this;
182   previous_ = other;
183   other->next_ = this;
184 }
185 
186 
Unlink()187 void PreallocatedStorage::Unlink() {
188   next_->previous_ = previous_;
189   previous_->next_ = next_;
190 }
191 
192 
PreallocatedStorage(size_t size)193 PreallocatedStorage::PreallocatedStorage(size_t size)
194   : size_(size) {
195   previous_ = next_ = this;
196 }
197 
198 } }  // namespace v8::internal
199