sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 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 | |
| 30 | #include "log-utils.h" |
| 31 | |
| 32 | namespace v8 { |
| 33 | namespace internal { |
| 34 | |
| 35 | #ifdef ENABLE_LOGGING_AND_PROFILING |
| 36 | |
| 37 | LogDynamicBuffer::LogDynamicBuffer( |
| 38 | int block_size, int max_size, const char* seal, int seal_size) |
| 39 | : block_size_(block_size), |
| 40 | max_size_(max_size - (max_size % block_size_)), |
| 41 | seal_(seal), |
| 42 | seal_size_(seal_size), |
| 43 | blocks_(max_size_ / block_size_ + 1), |
| 44 | write_pos_(0), block_index_(0), block_write_pos_(0), is_sealed_(false) { |
| 45 | ASSERT(BlocksCount() > 0); |
| 46 | AllocateBlock(0); |
| 47 | for (int i = 1; i < BlocksCount(); ++i) { |
| 48 | blocks_[i] = NULL; |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | |
| 53 | LogDynamicBuffer::~LogDynamicBuffer() { |
| 54 | for (int i = 0; i < BlocksCount(); ++i) { |
| 55 | DeleteArray(blocks_[i]); |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | |
| 60 | int LogDynamicBuffer::Read(int from_pos, char* dest_buf, int buf_size) { |
| 61 | if (buf_size == 0) return 0; |
| 62 | int read_pos = from_pos; |
| 63 | int block_read_index = BlockIndex(from_pos); |
| 64 | int block_read_pos = PosInBlock(from_pos); |
| 65 | int dest_buf_pos = 0; |
| 66 | // Read until dest_buf is filled, or write_pos_ encountered. |
| 67 | while (read_pos < write_pos_ && dest_buf_pos < buf_size) { |
| 68 | const int read_size = Min(write_pos_ - read_pos, |
| 69 | Min(buf_size - dest_buf_pos, block_size_ - block_read_pos)); |
| 70 | memcpy(dest_buf + dest_buf_pos, |
| 71 | blocks_[block_read_index] + block_read_pos, read_size); |
| 72 | block_read_pos += read_size; |
| 73 | dest_buf_pos += read_size; |
| 74 | read_pos += read_size; |
| 75 | if (block_read_pos == block_size_) { |
| 76 | block_read_pos = 0; |
| 77 | ++block_read_index; |
| 78 | } |
| 79 | } |
| 80 | return dest_buf_pos; |
| 81 | } |
| 82 | |
| 83 | |
| 84 | int LogDynamicBuffer::Seal() { |
| 85 | WriteInternal(seal_, seal_size_); |
| 86 | is_sealed_ = true; |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | |
| 91 | int LogDynamicBuffer::Write(const char* data, int data_size) { |
| 92 | if (is_sealed_) { |
| 93 | return 0; |
| 94 | } |
| 95 | if ((write_pos_ + data_size) <= (max_size_ - seal_size_)) { |
| 96 | return WriteInternal(data, data_size); |
| 97 | } else { |
| 98 | return Seal(); |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | |
| 103 | int LogDynamicBuffer::WriteInternal(const char* data, int data_size) { |
| 104 | int data_pos = 0; |
| 105 | while (data_pos < data_size) { |
| 106 | const int write_size = |
| 107 | Min(data_size - data_pos, block_size_ - block_write_pos_); |
| 108 | memcpy(blocks_[block_index_] + block_write_pos_, data + data_pos, |
| 109 | write_size); |
| 110 | block_write_pos_ += write_size; |
| 111 | data_pos += write_size; |
| 112 | if (block_write_pos_ == block_size_) { |
| 113 | block_write_pos_ = 0; |
| 114 | AllocateBlock(++block_index_); |
| 115 | } |
| 116 | } |
| 117 | write_pos_ += data_size; |
| 118 | return data_size; |
| 119 | } |
| 120 | |
| 121 | |
| 122 | bool Log::is_stopped_ = false; |
| 123 | Log::WritePtr Log::Write = NULL; |
| 124 | FILE* Log::output_handle_ = NULL; |
| 125 | LogDynamicBuffer* Log::output_buffer_ = NULL; |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 126 | // Must be the same message as in Logger::PauseProfiler. |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 127 | const char* Log::kDynamicBufferSeal = "profiler,\"pause\"\n"; |
| 128 | Mutex* Log::mutex_ = NULL; |
| 129 | char* Log::message_buffer_ = NULL; |
| 130 | |
| 131 | |
| 132 | void Log::Init() { |
| 133 | mutex_ = OS::CreateMutex(); |
| 134 | message_buffer_ = NewArray<char>(kMessageBufferSize); |
| 135 | } |
| 136 | |
| 137 | |
| 138 | void Log::OpenStdout() { |
| 139 | ASSERT(!IsEnabled()); |
| 140 | output_handle_ = stdout; |
| 141 | Write = WriteToFile; |
| 142 | Init(); |
| 143 | } |
| 144 | |
| 145 | |
| 146 | void Log::OpenFile(const char* name) { |
| 147 | ASSERT(!IsEnabled()); |
| 148 | output_handle_ = OS::FOpen(name, OS::LogFileOpenMode); |
| 149 | Write = WriteToFile; |
| 150 | Init(); |
| 151 | } |
| 152 | |
| 153 | |
| 154 | void Log::OpenMemoryBuffer() { |
| 155 | ASSERT(!IsEnabled()); |
| 156 | output_buffer_ = new LogDynamicBuffer( |
| 157 | kDynamicBufferBlockSize, kMaxDynamicBufferSize, |
| 158 | kDynamicBufferSeal, strlen(kDynamicBufferSeal)); |
| 159 | Write = WriteToMemory; |
| 160 | Init(); |
| 161 | } |
| 162 | |
| 163 | |
| 164 | void Log::Close() { |
| 165 | if (Write == WriteToFile) { |
| 166 | fclose(output_handle_); |
| 167 | output_handle_ = NULL; |
| 168 | } else if (Write == WriteToMemory) { |
| 169 | delete output_buffer_; |
| 170 | output_buffer_ = NULL; |
| 171 | } else { |
| 172 | ASSERT(Write == NULL); |
| 173 | } |
| 174 | Write = NULL; |
| 175 | |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 176 | DeleteArray(message_buffer_); |
| 177 | message_buffer_ = NULL; |
| 178 | |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 179 | delete mutex_; |
| 180 | mutex_ = NULL; |
| 181 | |
| 182 | is_stopped_ = false; |
| 183 | } |
| 184 | |
| 185 | |
| 186 | int Log::GetLogLines(int from_pos, char* dest_buf, int max_size) { |
| 187 | if (Write != WriteToMemory) return 0; |
| 188 | ASSERT(output_buffer_ != NULL); |
| 189 | ASSERT(from_pos >= 0); |
| 190 | ASSERT(max_size >= 0); |
| 191 | int actual_size = output_buffer_->Read(from_pos, dest_buf, max_size); |
| 192 | ASSERT(actual_size <= max_size); |
| 193 | if (actual_size == 0) return 0; |
| 194 | |
| 195 | // Find previous log line boundary. |
| 196 | char* end_pos = dest_buf + actual_size - 1; |
| 197 | while (end_pos >= dest_buf && *end_pos != '\n') --end_pos; |
| 198 | actual_size = end_pos - dest_buf + 1; |
| 199 | ASSERT(actual_size <= max_size); |
| 200 | return actual_size; |
| 201 | } |
| 202 | |
| 203 | |
| 204 | LogMessageBuilder::WriteFailureHandler |
| 205 | LogMessageBuilder::write_failure_handler = NULL; |
| 206 | |
| 207 | |
| 208 | LogMessageBuilder::LogMessageBuilder(): sl(Log::mutex_), pos_(0) { |
| 209 | ASSERT(Log::message_buffer_ != NULL); |
| 210 | } |
| 211 | |
| 212 | |
| 213 | void LogMessageBuilder::Append(const char* format, ...) { |
| 214 | Vector<char> buf(Log::message_buffer_ + pos_, |
| 215 | Log::kMessageBufferSize - pos_); |
| 216 | va_list args; |
| 217 | va_start(args, format); |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 218 | AppendVA(format, args); |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 219 | va_end(args); |
| 220 | ASSERT(pos_ <= Log::kMessageBufferSize); |
| 221 | } |
| 222 | |
| 223 | |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 224 | void LogMessageBuilder::AppendVA(const char* format, va_list args) { |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 225 | Vector<char> buf(Log::message_buffer_ + pos_, |
| 226 | Log::kMessageBufferSize - pos_); |
| 227 | int result = v8::internal::OS::VSNPrintF(buf, format, args); |
| 228 | |
| 229 | // Result is -1 if output was truncated. |
| 230 | if (result >= 0) { |
| 231 | pos_ += result; |
| 232 | } else { |
| 233 | pos_ = Log::kMessageBufferSize; |
| 234 | } |
| 235 | ASSERT(pos_ <= Log::kMessageBufferSize); |
| 236 | } |
| 237 | |
| 238 | |
| 239 | void LogMessageBuilder::Append(const char c) { |
| 240 | if (pos_ < Log::kMessageBufferSize) { |
| 241 | Log::message_buffer_[pos_++] = c; |
| 242 | } |
| 243 | ASSERT(pos_ <= Log::kMessageBufferSize); |
| 244 | } |
| 245 | |
| 246 | |
| 247 | void LogMessageBuilder::Append(String* str) { |
| 248 | AssertNoAllocation no_heap_allocation; // Ensure string stay valid. |
| 249 | int length = str->length(); |
| 250 | for (int i = 0; i < length; i++) { |
| 251 | Append(static_cast<char>(str->Get(i))); |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 256 | void LogMessageBuilder::AppendAddress(Address addr) { |
| 257 | static Address last_address_ = NULL; |
| 258 | AppendAddress(addr, last_address_); |
| 259 | last_address_ = addr; |
| 260 | } |
| 261 | |
| 262 | |
| 263 | void LogMessageBuilder::AppendAddress(Address addr, Address bias) { |
ager@chromium.org | 5aa501c | 2009-06-23 07:57:28 +0000 | [diff] [blame] | 264 | if (!FLAG_compress_log) { |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 265 | Append("0x%" V8PRIxPTR, addr); |
ager@chromium.org | 5aa501c | 2009-06-23 07:57:28 +0000 | [diff] [blame] | 266 | } else if (bias == NULL) { |
| 267 | Append("%" V8PRIxPTR, addr); |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 268 | } else { |
ager@chromium.org | 5aa501c | 2009-06-23 07:57:28 +0000 | [diff] [blame] | 269 | uintptr_t delta; |
| 270 | char sign; |
| 271 | if (addr >= bias) { |
| 272 | delta = addr - bias; |
| 273 | sign = '+'; |
| 274 | } else { |
| 275 | delta = bias - addr; |
| 276 | sign = '-'; |
| 277 | } |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 278 | Append("%c%" V8PRIxPTR, sign, delta); |
| 279 | } |
| 280 | } |
| 281 | |
| 282 | |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 283 | void LogMessageBuilder::AppendDetailed(String* str, bool show_impl_info) { |
| 284 | AssertNoAllocation no_heap_allocation; // Ensure string stay valid. |
| 285 | int len = str->length(); |
| 286 | if (len > 0x1000) |
| 287 | len = 0x1000; |
| 288 | if (show_impl_info) { |
| 289 | Append(str->IsAsciiRepresentation() ? 'a' : '2'); |
| 290 | if (StringShape(str).IsExternal()) |
| 291 | Append('e'); |
| 292 | if (StringShape(str).IsSymbol()) |
| 293 | Append('#'); |
| 294 | Append(":%i:", str->length()); |
| 295 | } |
| 296 | for (int i = 0; i < len; i++) { |
| 297 | uc32 c = str->Get(i); |
| 298 | if (c > 0xff) { |
| 299 | Append("\\u%04x", c); |
| 300 | } else if (c < 32 || c > 126) { |
| 301 | Append("\\x%02x", c); |
| 302 | } else if (c == ',') { |
| 303 | Append("\\,"); |
| 304 | } else if (c == '\\') { |
| 305 | Append("\\\\"); |
| 306 | } else { |
| 307 | Append("%lc", c); |
| 308 | } |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | |
christian.plesner.hansen@gmail.com | 2bc58ef | 2009-09-22 10:00:30 +0000 | [diff] [blame^] | 313 | void LogMessageBuilder::AppendStringPart(const char* str, int len) { |
| 314 | if (pos_ + len > Log::kMessageBufferSize) { |
| 315 | len = Log::kMessageBufferSize - pos_; |
| 316 | ASSERT(len >= 0); |
| 317 | if (len == 0) return; |
| 318 | } |
| 319 | Vector<char> buf(Log::message_buffer_ + pos_, |
| 320 | Log::kMessageBufferSize - pos_); |
| 321 | OS::StrNCpy(buf, str, len); |
| 322 | pos_ += len; |
| 323 | ASSERT(pos_ <= Log::kMessageBufferSize); |
| 324 | } |
| 325 | |
| 326 | |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 327 | bool LogMessageBuilder::StoreInCompressor(LogRecordCompressor* compressor) { |
| 328 | return compressor->Store(Vector<const char>(Log::message_buffer_, pos_)); |
| 329 | } |
| 330 | |
| 331 | |
| 332 | bool LogMessageBuilder::RetrieveCompressedPrevious( |
| 333 | LogRecordCompressor* compressor, const char* prefix) { |
| 334 | pos_ = 0; |
| 335 | if (prefix[0] != '\0') Append(prefix); |
| 336 | Vector<char> prev_record(Log::message_buffer_ + pos_, |
| 337 | Log::kMessageBufferSize - pos_); |
| 338 | const bool has_prev = compressor->RetrievePreviousCompressed(&prev_record); |
| 339 | if (!has_prev) return false; |
| 340 | pos_ += prev_record.length(); |
| 341 | return true; |
| 342 | } |
| 343 | |
| 344 | |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 345 | void LogMessageBuilder::WriteToLogFile() { |
| 346 | ASSERT(pos_ <= Log::kMessageBufferSize); |
| 347 | const int written = Log::Write(Log::message_buffer_, pos_); |
| 348 | if (written != pos_ && write_failure_handler != NULL) { |
| 349 | write_failure_handler(); |
| 350 | } |
| 351 | } |
| 352 | |
| 353 | |
| 354 | void LogMessageBuilder::WriteCStringToLogFile(const char* str) { |
| 355 | const int len = strlen(str); |
| 356 | const int written = Log::Write(str, len); |
| 357 | if (written != len && write_failure_handler != NULL) { |
| 358 | write_failure_handler(); |
| 359 | } |
| 360 | } |
| 361 | |
ager@chromium.org | eadaf22 | 2009-06-16 09:43:10 +0000 | [diff] [blame] | 362 | |
| 363 | // Formatting string for back references to the whole line. E.g. "#2" means |
| 364 | // "the second line above". |
| 365 | const char* LogRecordCompressor::kLineBackwardReferenceFormat = "#%d"; |
| 366 | |
| 367 | // Formatting string for back references. E.g. "#2:10" means |
| 368 | // "the second line above, start from char 10 (0-based)". |
| 369 | const char* LogRecordCompressor::kBackwardReferenceFormat = "#%d:%d"; |
| 370 | |
| 371 | |
| 372 | LogRecordCompressor::~LogRecordCompressor() { |
| 373 | for (int i = 0; i < buffer_.length(); ++i) { |
| 374 | buffer_[i].Dispose(); |
| 375 | } |
| 376 | } |
| 377 | |
| 378 | |
| 379 | static int GetNumberLength(int number) { |
| 380 | ASSERT(number >= 0); |
| 381 | ASSERT(number < 10000); |
| 382 | if (number < 10) return 1; |
| 383 | if (number < 100) return 2; |
| 384 | if (number < 1000) return 3; |
| 385 | return 4; |
| 386 | } |
| 387 | |
| 388 | |
| 389 | int LogRecordCompressor::GetBackwardReferenceSize(int distance, int pos) { |
| 390 | // See kLineBackwardReferenceFormat and kBackwardReferenceFormat. |
| 391 | return pos == 0 ? GetNumberLength(distance) + 1 |
| 392 | : GetNumberLength(distance) + GetNumberLength(pos) + 2; |
| 393 | } |
| 394 | |
| 395 | |
| 396 | void LogRecordCompressor::PrintBackwardReference(Vector<char> dest, |
| 397 | int distance, |
| 398 | int pos) { |
| 399 | if (pos == 0) { |
| 400 | OS::SNPrintF(dest, kLineBackwardReferenceFormat, distance); |
| 401 | } else { |
| 402 | OS::SNPrintF(dest, kBackwardReferenceFormat, distance, pos); |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | |
| 407 | bool LogRecordCompressor::Store(const Vector<const char>& record) { |
| 408 | // Check if the record is the same as the last stored one. |
| 409 | if (curr_ != -1) { |
| 410 | Vector<const char>& curr = buffer_[curr_]; |
| 411 | if (record.length() == curr.length() |
| 412 | && strncmp(record.start(), curr.start(), record.length()) == 0) { |
| 413 | return false; |
| 414 | } |
| 415 | } |
| 416 | // buffer_ is circular. |
| 417 | prev_ = curr_++; |
| 418 | curr_ %= buffer_.length(); |
| 419 | Vector<char> record_copy = Vector<char>::New(record.length()); |
| 420 | memcpy(record_copy.start(), record.start(), record.length()); |
| 421 | buffer_[curr_].Dispose(); |
| 422 | buffer_[curr_] = |
| 423 | Vector<const char>(record_copy.start(), record_copy.length()); |
| 424 | return true; |
| 425 | } |
| 426 | |
| 427 | |
| 428 | bool LogRecordCompressor::RetrievePreviousCompressed( |
| 429 | Vector<char>* prev_record) { |
| 430 | if (prev_ == -1) return false; |
| 431 | |
| 432 | int index = prev_; |
| 433 | // Distance from prev_. |
| 434 | int distance = 0; |
| 435 | // Best compression result among records in the buffer. |
| 436 | struct { |
| 437 | intptr_t truncated_len; |
| 438 | int distance; |
| 439 | int copy_from_pos; |
| 440 | int backref_size; |
| 441 | } best = {-1, 0, 0, 0}; |
| 442 | Vector<const char>& prev = buffer_[prev_]; |
| 443 | const char* const prev_start = prev.start(); |
| 444 | const char* const prev_end = prev.start() + prev.length(); |
| 445 | do { |
| 446 | // We're moving backwards until we reach the current record. |
| 447 | // Remember that buffer_ is circular. |
| 448 | if (--index == -1) index = buffer_.length() - 1; |
| 449 | ++distance; |
| 450 | if (index == curr_) break; |
| 451 | |
| 452 | Vector<const char>& data = buffer_[index]; |
| 453 | if (data.start() == NULL) break; |
| 454 | const char* const data_end = data.start() + data.length(); |
| 455 | const char* prev_ptr = prev_end; |
| 456 | const char* data_ptr = data_end; |
| 457 | // Compare strings backwards, stop on the last matching character. |
| 458 | while (prev_ptr != prev_start && data_ptr != data.start() |
| 459 | && *(prev_ptr - 1) == *(data_ptr - 1)) { |
| 460 | --prev_ptr; |
| 461 | --data_ptr; |
| 462 | } |
| 463 | const intptr_t truncated_len = prev_end - prev_ptr; |
| 464 | const int copy_from_pos = data_ptr - data.start(); |
| 465 | // Check if the length of compressed tail is enough. |
| 466 | if (truncated_len <= kMaxBackwardReferenceSize |
| 467 | && truncated_len <= GetBackwardReferenceSize(distance, copy_from_pos)) { |
| 468 | continue; |
| 469 | } |
| 470 | |
| 471 | // Record compression results. |
| 472 | if (truncated_len > best.truncated_len) { |
| 473 | best.truncated_len = truncated_len; |
| 474 | best.distance = distance; |
| 475 | best.copy_from_pos = copy_from_pos; |
| 476 | best.backref_size = GetBackwardReferenceSize(distance, copy_from_pos); |
| 477 | } |
| 478 | } while (true); |
| 479 | |
| 480 | if (best.distance == 0) { |
| 481 | // Can't compress the previous record. Return as is. |
| 482 | ASSERT(prev_record->length() >= prev.length()); |
| 483 | memcpy(prev_record->start(), prev.start(), prev.length()); |
| 484 | prev_record->Truncate(prev.length()); |
| 485 | } else { |
| 486 | // Copy the uncompressible part unchanged. |
| 487 | const intptr_t unchanged_len = prev.length() - best.truncated_len; |
| 488 | // + 1 for '\0'. |
| 489 | ASSERT(prev_record->length() >= unchanged_len + best.backref_size + 1); |
| 490 | memcpy(prev_record->start(), prev.start(), unchanged_len); |
| 491 | // Append the backward reference. |
| 492 | Vector<char> backref( |
| 493 | prev_record->start() + unchanged_len, best.backref_size + 1); |
| 494 | PrintBackwardReference(backref, best.distance, best.copy_from_pos); |
| 495 | ASSERT(strlen(backref.start()) - best.backref_size == 0); |
| 496 | prev_record->Truncate(unchanged_len + best.backref_size); |
| 497 | } |
| 498 | return true; |
| 499 | } |
| 500 | |
sgjesse@chromium.org | 755c5b1 | 2009-05-29 11:04:38 +0000 | [diff] [blame] | 501 | #endif // ENABLE_LOGGING_AND_PROFILING |
| 502 | |
| 503 | } } // namespace v8::internal |