1 // Copyright 2009 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/regexp/regexp-stack.h" 6 7 #include "src/isolate.h" 8 9 namespace v8 { 10 namespace internal { 11 RegExpStackScope(Isolate * isolate)12RegExpStackScope::RegExpStackScope(Isolate* isolate) 13 : regexp_stack_(isolate->regexp_stack()) { 14 // Initialize, if not already initialized. 15 regexp_stack_->EnsureCapacity(0); 16 } 17 18 ~RegExpStackScope()19RegExpStackScope::~RegExpStackScope() { 20 // Reset the buffer if it has grown. 21 regexp_stack_->Reset(); 22 } 23 24 RegExpStack()25RegExpStack::RegExpStack() 26 : isolate_(NULL) { 27 } 28 29 ~RegExpStack()30RegExpStack::~RegExpStack() { 31 thread_local_.Free(); 32 } 33 34 ArchiveStack(char * to)35char* RegExpStack::ArchiveStack(char* to) { 36 size_t size = sizeof(thread_local_); 37 MemCopy(reinterpret_cast<void*>(to), &thread_local_, size); 38 thread_local_ = ThreadLocal(); 39 return to + size; 40 } 41 42 RestoreStack(char * from)43char* RegExpStack::RestoreStack(char* from) { 44 size_t size = sizeof(thread_local_); 45 MemCopy(&thread_local_, reinterpret_cast<void*>(from), size); 46 return from + size; 47 } 48 49 Reset()50void RegExpStack::Reset() { 51 if (thread_local_.memory_size_ > kMinimumStackSize) { 52 DeleteArray(thread_local_.memory_); 53 thread_local_ = ThreadLocal(); 54 } 55 } 56 57 Free()58void RegExpStack::ThreadLocal::Free() { 59 if (memory_size_ > 0) { 60 DeleteArray(memory_); 61 Clear(); 62 } 63 } 64 65 EnsureCapacity(size_t size)66Address RegExpStack::EnsureCapacity(size_t size) { 67 if (size > kMaximumStackSize) return NULL; 68 if (size < kMinimumStackSize) size = kMinimumStackSize; 69 if (thread_local_.memory_size_ < size) { 70 Address new_memory = NewArray<byte>(static_cast<int>(size)); 71 if (thread_local_.memory_size_ > 0) { 72 // Copy original memory into top of new memory. 73 MemCopy(reinterpret_cast<void*>(new_memory + size - 74 thread_local_.memory_size_), 75 reinterpret_cast<void*>(thread_local_.memory_), 76 thread_local_.memory_size_); 77 DeleteArray(thread_local_.memory_); 78 } 79 thread_local_.memory_ = new_memory; 80 thread_local_.memory_size_ = size; 81 thread_local_.limit_ = new_memory + kStackLimitSlack * kPointerSize; 82 } 83 return thread_local_.memory_ + thread_local_.memory_size_; 84 } 85 86 87 } // namespace internal 88 } // namespace v8 89