1 // Copyright 2009 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 "v8.h"
29 #include "regexp-stack.h"
30
31 namespace v8 {
32 namespace internal {
33
RegExpStackScope(Isolate * isolate)34 RegExpStackScope::RegExpStackScope(Isolate* isolate)
35 : regexp_stack_(isolate->regexp_stack()) {
36 // Initialize, if not already initialized.
37 regexp_stack_->EnsureCapacity(0);
38 }
39
40
~RegExpStackScope()41 RegExpStackScope::~RegExpStackScope() {
42 ASSERT(Isolate::Current() == regexp_stack_->isolate_);
43 // Reset the buffer if it has grown.
44 regexp_stack_->Reset();
45 }
46
47
RegExpStack()48 RegExpStack::RegExpStack()
49 : isolate_(NULL) {
50 }
51
52
~RegExpStack()53 RegExpStack::~RegExpStack() {
54 }
55
56
ArchiveStack(char * to)57 char* RegExpStack::ArchiveStack(char* to) {
58 size_t size = sizeof(thread_local_);
59 memcpy(reinterpret_cast<void*>(to),
60 &thread_local_,
61 size);
62 thread_local_ = ThreadLocal();
63 return to + size;
64 }
65
66
RestoreStack(char * from)67 char* RegExpStack::RestoreStack(char* from) {
68 size_t size = sizeof(thread_local_);
69 memcpy(&thread_local_, reinterpret_cast<void*>(from), size);
70 return from + size;
71 }
72
73
Reset()74 void RegExpStack::Reset() {
75 if (thread_local_.memory_size_ > kMinimumStackSize) {
76 DeleteArray(thread_local_.memory_);
77 thread_local_ = ThreadLocal();
78 }
79 }
80
81
Free()82 void RegExpStack::ThreadLocal::Free() {
83 if (memory_size_ > 0) {
84 DeleteArray(memory_);
85 Clear();
86 }
87 }
88
89
EnsureCapacity(size_t size)90 Address RegExpStack::EnsureCapacity(size_t size) {
91 if (size > kMaximumStackSize) return NULL;
92 if (size < kMinimumStackSize) size = kMinimumStackSize;
93 if (thread_local_.memory_size_ < size) {
94 Address new_memory = NewArray<byte>(static_cast<int>(size));
95 if (thread_local_.memory_size_ > 0) {
96 // Copy original memory into top of new memory.
97 memcpy(reinterpret_cast<void*>(
98 new_memory + size - thread_local_.memory_size_),
99 reinterpret_cast<void*>(thread_local_.memory_),
100 thread_local_.memory_size_);
101 DeleteArray(thread_local_.memory_);
102 }
103 thread_local_.memory_ = new_memory;
104 thread_local_.memory_size_ = size;
105 thread_local_.limit_ = new_memory + kStackLimitSlack * kPointerSize;
106 }
107 return thread_local_.memory_ + thread_local_.memory_size_;
108 }
109
110
111 }} // namespace v8::internal
112