Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2012 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/debug/liveedit.h" |
| 6 | |
| 7 | #include "src/ast/scopeinfo.h" |
| 8 | #include "src/ast/scopes.h" |
| 9 | #include "src/code-stubs.h" |
| 10 | #include "src/compilation-cache.h" |
| 11 | #include "src/compiler.h" |
| 12 | #include "src/debug/debug.h" |
| 13 | #include "src/deoptimizer.h" |
| 14 | #include "src/frames-inl.h" |
| 15 | #include "src/global-handles.h" |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 16 | #include "src/interpreter/source-position-table.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 17 | #include "src/isolate-inl.h" |
| 18 | #include "src/messages.h" |
| 19 | #include "src/parsing/parser.h" |
| 20 | #include "src/v8.h" |
| 21 | #include "src/v8memory.h" |
| 22 | |
| 23 | namespace v8 { |
| 24 | namespace internal { |
| 25 | |
| 26 | void SetElementSloppy(Handle<JSObject> object, |
| 27 | uint32_t index, |
| 28 | Handle<Object> value) { |
| 29 | // Ignore return value from SetElement. It can only be a failure if there |
| 30 | // are element setters causing exceptions and the debugger context has none |
| 31 | // of these. |
| 32 | Object::SetElement(object->GetIsolate(), object, index, value, SLOPPY) |
| 33 | .Assert(); |
| 34 | } |
| 35 | |
| 36 | |
| 37 | // A simple implementation of dynamic programming algorithm. It solves |
| 38 | // the problem of finding the difference of 2 arrays. It uses a table of results |
| 39 | // of subproblems. Each cell contains a number together with 2-bit flag |
| 40 | // that helps building the chunk list. |
| 41 | class Differencer { |
| 42 | public: |
| 43 | explicit Differencer(Comparator::Input* input) |
| 44 | : input_(input), len1_(input->GetLength1()), len2_(input->GetLength2()) { |
| 45 | buffer_ = NewArray<int>(len1_ * len2_); |
| 46 | } |
| 47 | ~Differencer() { |
| 48 | DeleteArray(buffer_); |
| 49 | } |
| 50 | |
| 51 | void Initialize() { |
| 52 | int array_size = len1_ * len2_; |
| 53 | for (int i = 0; i < array_size; i++) { |
| 54 | buffer_[i] = kEmptyCellValue; |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | // Makes sure that result for the full problem is calculated and stored |
| 59 | // in the table together with flags showing a path through subproblems. |
| 60 | void FillTable() { |
| 61 | CompareUpToTail(0, 0); |
| 62 | } |
| 63 | |
| 64 | void SaveResult(Comparator::Output* chunk_writer) { |
| 65 | ResultWriter writer(chunk_writer); |
| 66 | |
| 67 | int pos1 = 0; |
| 68 | int pos2 = 0; |
| 69 | while (true) { |
| 70 | if (pos1 < len1_) { |
| 71 | if (pos2 < len2_) { |
| 72 | Direction dir = get_direction(pos1, pos2); |
| 73 | switch (dir) { |
| 74 | case EQ: |
| 75 | writer.eq(); |
| 76 | pos1++; |
| 77 | pos2++; |
| 78 | break; |
| 79 | case SKIP1: |
| 80 | writer.skip1(1); |
| 81 | pos1++; |
| 82 | break; |
| 83 | case SKIP2: |
| 84 | case SKIP_ANY: |
| 85 | writer.skip2(1); |
| 86 | pos2++; |
| 87 | break; |
| 88 | default: |
| 89 | UNREACHABLE(); |
| 90 | } |
| 91 | } else { |
| 92 | writer.skip1(len1_ - pos1); |
| 93 | break; |
| 94 | } |
| 95 | } else { |
| 96 | if (len2_ != pos2) { |
| 97 | writer.skip2(len2_ - pos2); |
| 98 | } |
| 99 | break; |
| 100 | } |
| 101 | } |
| 102 | writer.close(); |
| 103 | } |
| 104 | |
| 105 | private: |
| 106 | Comparator::Input* input_; |
| 107 | int* buffer_; |
| 108 | int len1_; |
| 109 | int len2_; |
| 110 | |
| 111 | enum Direction { |
| 112 | EQ = 0, |
| 113 | SKIP1, |
| 114 | SKIP2, |
| 115 | SKIP_ANY, |
| 116 | |
| 117 | MAX_DIRECTION_FLAG_VALUE = SKIP_ANY |
| 118 | }; |
| 119 | |
| 120 | // Computes result for a subtask and optionally caches it in the buffer table. |
| 121 | // All results values are shifted to make space for flags in the lower bits. |
| 122 | int CompareUpToTail(int pos1, int pos2) { |
| 123 | if (pos1 < len1_) { |
| 124 | if (pos2 < len2_) { |
| 125 | int cached_res = get_value4(pos1, pos2); |
| 126 | if (cached_res == kEmptyCellValue) { |
| 127 | Direction dir; |
| 128 | int res; |
| 129 | if (input_->Equals(pos1, pos2)) { |
| 130 | res = CompareUpToTail(pos1 + 1, pos2 + 1); |
| 131 | dir = EQ; |
| 132 | } else { |
| 133 | int res1 = CompareUpToTail(pos1 + 1, pos2) + |
| 134 | (1 << kDirectionSizeBits); |
| 135 | int res2 = CompareUpToTail(pos1, pos2 + 1) + |
| 136 | (1 << kDirectionSizeBits); |
| 137 | if (res1 == res2) { |
| 138 | res = res1; |
| 139 | dir = SKIP_ANY; |
| 140 | } else if (res1 < res2) { |
| 141 | res = res1; |
| 142 | dir = SKIP1; |
| 143 | } else { |
| 144 | res = res2; |
| 145 | dir = SKIP2; |
| 146 | } |
| 147 | } |
| 148 | set_value4_and_dir(pos1, pos2, res, dir); |
| 149 | cached_res = res; |
| 150 | } |
| 151 | return cached_res; |
| 152 | } else { |
| 153 | return (len1_ - pos1) << kDirectionSizeBits; |
| 154 | } |
| 155 | } else { |
| 156 | return (len2_ - pos2) << kDirectionSizeBits; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | inline int& get_cell(int i1, int i2) { |
| 161 | return buffer_[i1 + i2 * len1_]; |
| 162 | } |
| 163 | |
| 164 | // Each cell keeps a value plus direction. Value is multiplied by 4. |
| 165 | void set_value4_and_dir(int i1, int i2, int value4, Direction dir) { |
| 166 | DCHECK((value4 & kDirectionMask) == 0); |
| 167 | get_cell(i1, i2) = value4 | dir; |
| 168 | } |
| 169 | |
| 170 | int get_value4(int i1, int i2) { |
| 171 | return get_cell(i1, i2) & (kMaxUInt32 ^ kDirectionMask); |
| 172 | } |
| 173 | Direction get_direction(int i1, int i2) { |
| 174 | return static_cast<Direction>(get_cell(i1, i2) & kDirectionMask); |
| 175 | } |
| 176 | |
| 177 | static const int kDirectionSizeBits = 2; |
| 178 | static const int kDirectionMask = (1 << kDirectionSizeBits) - 1; |
| 179 | static const int kEmptyCellValue = ~0u << kDirectionSizeBits; |
| 180 | |
| 181 | // This method only holds static assert statement (unfortunately you cannot |
| 182 | // place one in class scope). |
| 183 | void StaticAssertHolder() { |
| 184 | STATIC_ASSERT(MAX_DIRECTION_FLAG_VALUE < (1 << kDirectionSizeBits)); |
| 185 | } |
| 186 | |
| 187 | class ResultWriter { |
| 188 | public: |
| 189 | explicit ResultWriter(Comparator::Output* chunk_writer) |
| 190 | : chunk_writer_(chunk_writer), pos1_(0), pos2_(0), |
| 191 | pos1_begin_(-1), pos2_begin_(-1), has_open_chunk_(false) { |
| 192 | } |
| 193 | void eq() { |
| 194 | FlushChunk(); |
| 195 | pos1_++; |
| 196 | pos2_++; |
| 197 | } |
| 198 | void skip1(int len1) { |
| 199 | StartChunk(); |
| 200 | pos1_ += len1; |
| 201 | } |
| 202 | void skip2(int len2) { |
| 203 | StartChunk(); |
| 204 | pos2_ += len2; |
| 205 | } |
| 206 | void close() { |
| 207 | FlushChunk(); |
| 208 | } |
| 209 | |
| 210 | private: |
| 211 | Comparator::Output* chunk_writer_; |
| 212 | int pos1_; |
| 213 | int pos2_; |
| 214 | int pos1_begin_; |
| 215 | int pos2_begin_; |
| 216 | bool has_open_chunk_; |
| 217 | |
| 218 | void StartChunk() { |
| 219 | if (!has_open_chunk_) { |
| 220 | pos1_begin_ = pos1_; |
| 221 | pos2_begin_ = pos2_; |
| 222 | has_open_chunk_ = true; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | void FlushChunk() { |
| 227 | if (has_open_chunk_) { |
| 228 | chunk_writer_->AddChunk(pos1_begin_, pos2_begin_, |
| 229 | pos1_ - pos1_begin_, pos2_ - pos2_begin_); |
| 230 | has_open_chunk_ = false; |
| 231 | } |
| 232 | } |
| 233 | }; |
| 234 | }; |
| 235 | |
| 236 | |
| 237 | void Comparator::CalculateDifference(Comparator::Input* input, |
| 238 | Comparator::Output* result_writer) { |
| 239 | Differencer differencer(input); |
| 240 | differencer.Initialize(); |
| 241 | differencer.FillTable(); |
| 242 | differencer.SaveResult(result_writer); |
| 243 | } |
| 244 | |
| 245 | |
| 246 | static bool CompareSubstrings(Handle<String> s1, int pos1, |
| 247 | Handle<String> s2, int pos2, int len) { |
| 248 | for (int i = 0; i < len; i++) { |
| 249 | if (s1->Get(i + pos1) != s2->Get(i + pos2)) { |
| 250 | return false; |
| 251 | } |
| 252 | } |
| 253 | return true; |
| 254 | } |
| 255 | |
| 256 | |
| 257 | // Additional to Input interface. Lets switch Input range to subrange. |
| 258 | // More elegant way would be to wrap one Input as another Input object |
| 259 | // and translate positions there, but that would cost us additional virtual |
| 260 | // call per comparison. |
| 261 | class SubrangableInput : public Comparator::Input { |
| 262 | public: |
| 263 | virtual void SetSubrange1(int offset, int len) = 0; |
| 264 | virtual void SetSubrange2(int offset, int len) = 0; |
| 265 | }; |
| 266 | |
| 267 | |
| 268 | class SubrangableOutput : public Comparator::Output { |
| 269 | public: |
| 270 | virtual void SetSubrange1(int offset, int len) = 0; |
| 271 | virtual void SetSubrange2(int offset, int len) = 0; |
| 272 | }; |
| 273 | |
| 274 | |
| 275 | static int min(int a, int b) { |
| 276 | return a < b ? a : b; |
| 277 | } |
| 278 | |
| 279 | |
| 280 | // Finds common prefix and suffix in input. This parts shouldn't take space in |
| 281 | // linear programming table. Enable subranging in input and output. |
| 282 | static void NarrowDownInput(SubrangableInput* input, |
| 283 | SubrangableOutput* output) { |
| 284 | const int len1 = input->GetLength1(); |
| 285 | const int len2 = input->GetLength2(); |
| 286 | |
| 287 | int common_prefix_len; |
| 288 | int common_suffix_len; |
| 289 | |
| 290 | { |
| 291 | common_prefix_len = 0; |
| 292 | int prefix_limit = min(len1, len2); |
| 293 | while (common_prefix_len < prefix_limit && |
| 294 | input->Equals(common_prefix_len, common_prefix_len)) { |
| 295 | common_prefix_len++; |
| 296 | } |
| 297 | |
| 298 | common_suffix_len = 0; |
| 299 | int suffix_limit = min(len1 - common_prefix_len, len2 - common_prefix_len); |
| 300 | |
| 301 | while (common_suffix_len < suffix_limit && |
| 302 | input->Equals(len1 - common_suffix_len - 1, |
| 303 | len2 - common_suffix_len - 1)) { |
| 304 | common_suffix_len++; |
| 305 | } |
| 306 | } |
| 307 | |
| 308 | if (common_prefix_len > 0 || common_suffix_len > 0) { |
| 309 | int new_len1 = len1 - common_suffix_len - common_prefix_len; |
| 310 | int new_len2 = len2 - common_suffix_len - common_prefix_len; |
| 311 | |
| 312 | input->SetSubrange1(common_prefix_len, new_len1); |
| 313 | input->SetSubrange2(common_prefix_len, new_len2); |
| 314 | |
| 315 | output->SetSubrange1(common_prefix_len, new_len1); |
| 316 | output->SetSubrange2(common_prefix_len, new_len2); |
| 317 | } |
| 318 | } |
| 319 | |
| 320 | |
| 321 | // A helper class that writes chunk numbers into JSArray. |
| 322 | // Each chunk is stored as 3 array elements: (pos1_begin, pos1_end, pos2_end). |
| 323 | class CompareOutputArrayWriter { |
| 324 | public: |
| 325 | explicit CompareOutputArrayWriter(Isolate* isolate) |
| 326 | : array_(isolate->factory()->NewJSArray(10)), current_size_(0) {} |
| 327 | |
| 328 | Handle<JSArray> GetResult() { |
| 329 | return array_; |
| 330 | } |
| 331 | |
| 332 | void WriteChunk(int char_pos1, int char_pos2, int char_len1, int char_len2) { |
| 333 | Isolate* isolate = array_->GetIsolate(); |
| 334 | SetElementSloppy(array_, |
| 335 | current_size_, |
| 336 | Handle<Object>(Smi::FromInt(char_pos1), isolate)); |
| 337 | SetElementSloppy(array_, |
| 338 | current_size_ + 1, |
| 339 | Handle<Object>(Smi::FromInt(char_pos1 + char_len1), |
| 340 | isolate)); |
| 341 | SetElementSloppy(array_, |
| 342 | current_size_ + 2, |
| 343 | Handle<Object>(Smi::FromInt(char_pos2 + char_len2), |
| 344 | isolate)); |
| 345 | current_size_ += 3; |
| 346 | } |
| 347 | |
| 348 | private: |
| 349 | Handle<JSArray> array_; |
| 350 | int current_size_; |
| 351 | }; |
| 352 | |
| 353 | |
| 354 | // Represents 2 strings as 2 arrays of tokens. |
| 355 | // TODO(LiveEdit): Currently it's actually an array of charactres. |
| 356 | // Make array of tokens instead. |
| 357 | class TokensCompareInput : public Comparator::Input { |
| 358 | public: |
| 359 | TokensCompareInput(Handle<String> s1, int offset1, int len1, |
| 360 | Handle<String> s2, int offset2, int len2) |
| 361 | : s1_(s1), offset1_(offset1), len1_(len1), |
| 362 | s2_(s2), offset2_(offset2), len2_(len2) { |
| 363 | } |
| 364 | virtual int GetLength1() { |
| 365 | return len1_; |
| 366 | } |
| 367 | virtual int GetLength2() { |
| 368 | return len2_; |
| 369 | } |
| 370 | bool Equals(int index1, int index2) { |
| 371 | return s1_->Get(offset1_ + index1) == s2_->Get(offset2_ + index2); |
| 372 | } |
| 373 | |
| 374 | private: |
| 375 | Handle<String> s1_; |
| 376 | int offset1_; |
| 377 | int len1_; |
| 378 | Handle<String> s2_; |
| 379 | int offset2_; |
| 380 | int len2_; |
| 381 | }; |
| 382 | |
| 383 | |
| 384 | // Stores compare result in JSArray. Converts substring positions |
| 385 | // to absolute positions. |
| 386 | class TokensCompareOutput : public Comparator::Output { |
| 387 | public: |
| 388 | TokensCompareOutput(CompareOutputArrayWriter* array_writer, |
| 389 | int offset1, int offset2) |
| 390 | : array_writer_(array_writer), offset1_(offset1), offset2_(offset2) { |
| 391 | } |
| 392 | |
| 393 | void AddChunk(int pos1, int pos2, int len1, int len2) { |
| 394 | array_writer_->WriteChunk(pos1 + offset1_, pos2 + offset2_, len1, len2); |
| 395 | } |
| 396 | |
| 397 | private: |
| 398 | CompareOutputArrayWriter* array_writer_; |
| 399 | int offset1_; |
| 400 | int offset2_; |
| 401 | }; |
| 402 | |
| 403 | |
| 404 | // Wraps raw n-elements line_ends array as a list of n+1 lines. The last line |
| 405 | // never has terminating new line character. |
| 406 | class LineEndsWrapper { |
| 407 | public: |
| 408 | explicit LineEndsWrapper(Handle<String> string) |
| 409 | : ends_array_(String::CalculateLineEnds(string, false)), |
| 410 | string_len_(string->length()) { |
| 411 | } |
| 412 | int length() { |
| 413 | return ends_array_->length() + 1; |
| 414 | } |
| 415 | // Returns start for any line including start of the imaginary line after |
| 416 | // the last line. |
| 417 | int GetLineStart(int index) { |
| 418 | if (index == 0) { |
| 419 | return 0; |
| 420 | } else { |
| 421 | return GetLineEnd(index - 1); |
| 422 | } |
| 423 | } |
| 424 | int GetLineEnd(int index) { |
| 425 | if (index == ends_array_->length()) { |
| 426 | // End of the last line is always an end of the whole string. |
| 427 | // If the string ends with a new line character, the last line is an |
| 428 | // empty string after this character. |
| 429 | return string_len_; |
| 430 | } else { |
| 431 | return GetPosAfterNewLine(index); |
| 432 | } |
| 433 | } |
| 434 | |
| 435 | private: |
| 436 | Handle<FixedArray> ends_array_; |
| 437 | int string_len_; |
| 438 | |
| 439 | int GetPosAfterNewLine(int index) { |
| 440 | return Smi::cast(ends_array_->get(index))->value() + 1; |
| 441 | } |
| 442 | }; |
| 443 | |
| 444 | |
| 445 | // Represents 2 strings as 2 arrays of lines. |
| 446 | class LineArrayCompareInput : public SubrangableInput { |
| 447 | public: |
| 448 | LineArrayCompareInput(Handle<String> s1, Handle<String> s2, |
| 449 | LineEndsWrapper line_ends1, LineEndsWrapper line_ends2) |
| 450 | : s1_(s1), s2_(s2), line_ends1_(line_ends1), |
| 451 | line_ends2_(line_ends2), |
| 452 | subrange_offset1_(0), subrange_offset2_(0), |
| 453 | subrange_len1_(line_ends1_.length()), |
| 454 | subrange_len2_(line_ends2_.length()) { |
| 455 | } |
| 456 | int GetLength1() { |
| 457 | return subrange_len1_; |
| 458 | } |
| 459 | int GetLength2() { |
| 460 | return subrange_len2_; |
| 461 | } |
| 462 | bool Equals(int index1, int index2) { |
| 463 | index1 += subrange_offset1_; |
| 464 | index2 += subrange_offset2_; |
| 465 | |
| 466 | int line_start1 = line_ends1_.GetLineStart(index1); |
| 467 | int line_start2 = line_ends2_.GetLineStart(index2); |
| 468 | int line_end1 = line_ends1_.GetLineEnd(index1); |
| 469 | int line_end2 = line_ends2_.GetLineEnd(index2); |
| 470 | int len1 = line_end1 - line_start1; |
| 471 | int len2 = line_end2 - line_start2; |
| 472 | if (len1 != len2) { |
| 473 | return false; |
| 474 | } |
| 475 | return CompareSubstrings(s1_, line_start1, s2_, line_start2, |
| 476 | len1); |
| 477 | } |
| 478 | void SetSubrange1(int offset, int len) { |
| 479 | subrange_offset1_ = offset; |
| 480 | subrange_len1_ = len; |
| 481 | } |
| 482 | void SetSubrange2(int offset, int len) { |
| 483 | subrange_offset2_ = offset; |
| 484 | subrange_len2_ = len; |
| 485 | } |
| 486 | |
| 487 | private: |
| 488 | Handle<String> s1_; |
| 489 | Handle<String> s2_; |
| 490 | LineEndsWrapper line_ends1_; |
| 491 | LineEndsWrapper line_ends2_; |
| 492 | int subrange_offset1_; |
| 493 | int subrange_offset2_; |
| 494 | int subrange_len1_; |
| 495 | int subrange_len2_; |
| 496 | }; |
| 497 | |
| 498 | |
| 499 | // Stores compare result in JSArray. For each chunk tries to conduct |
| 500 | // a fine-grained nested diff token-wise. |
| 501 | class TokenizingLineArrayCompareOutput : public SubrangableOutput { |
| 502 | public: |
| 503 | TokenizingLineArrayCompareOutput(LineEndsWrapper line_ends1, |
| 504 | LineEndsWrapper line_ends2, |
| 505 | Handle<String> s1, Handle<String> s2) |
| 506 | : array_writer_(s1->GetIsolate()), |
| 507 | line_ends1_(line_ends1), line_ends2_(line_ends2), s1_(s1), s2_(s2), |
| 508 | subrange_offset1_(0), subrange_offset2_(0) { |
| 509 | } |
| 510 | |
| 511 | void AddChunk(int line_pos1, int line_pos2, int line_len1, int line_len2) { |
| 512 | line_pos1 += subrange_offset1_; |
| 513 | line_pos2 += subrange_offset2_; |
| 514 | |
| 515 | int char_pos1 = line_ends1_.GetLineStart(line_pos1); |
| 516 | int char_pos2 = line_ends2_.GetLineStart(line_pos2); |
| 517 | int char_len1 = line_ends1_.GetLineStart(line_pos1 + line_len1) - char_pos1; |
| 518 | int char_len2 = line_ends2_.GetLineStart(line_pos2 + line_len2) - char_pos2; |
| 519 | |
| 520 | if (char_len1 < CHUNK_LEN_LIMIT && char_len2 < CHUNK_LEN_LIMIT) { |
| 521 | // Chunk is small enough to conduct a nested token-level diff. |
| 522 | HandleScope subTaskScope(s1_->GetIsolate()); |
| 523 | |
| 524 | TokensCompareInput tokens_input(s1_, char_pos1, char_len1, |
| 525 | s2_, char_pos2, char_len2); |
| 526 | TokensCompareOutput tokens_output(&array_writer_, char_pos1, |
| 527 | char_pos2); |
| 528 | |
| 529 | Comparator::CalculateDifference(&tokens_input, &tokens_output); |
| 530 | } else { |
| 531 | array_writer_.WriteChunk(char_pos1, char_pos2, char_len1, char_len2); |
| 532 | } |
| 533 | } |
| 534 | void SetSubrange1(int offset, int len) { |
| 535 | subrange_offset1_ = offset; |
| 536 | } |
| 537 | void SetSubrange2(int offset, int len) { |
| 538 | subrange_offset2_ = offset; |
| 539 | } |
| 540 | |
| 541 | Handle<JSArray> GetResult() { |
| 542 | return array_writer_.GetResult(); |
| 543 | } |
| 544 | |
| 545 | private: |
| 546 | static const int CHUNK_LEN_LIMIT = 800; |
| 547 | |
| 548 | CompareOutputArrayWriter array_writer_; |
| 549 | LineEndsWrapper line_ends1_; |
| 550 | LineEndsWrapper line_ends2_; |
| 551 | Handle<String> s1_; |
| 552 | Handle<String> s2_; |
| 553 | int subrange_offset1_; |
| 554 | int subrange_offset2_; |
| 555 | }; |
| 556 | |
| 557 | |
| 558 | Handle<JSArray> LiveEdit::CompareStrings(Handle<String> s1, |
| 559 | Handle<String> s2) { |
| 560 | s1 = String::Flatten(s1); |
| 561 | s2 = String::Flatten(s2); |
| 562 | |
| 563 | LineEndsWrapper line_ends1(s1); |
| 564 | LineEndsWrapper line_ends2(s2); |
| 565 | |
| 566 | LineArrayCompareInput input(s1, s2, line_ends1, line_ends2); |
| 567 | TokenizingLineArrayCompareOutput output(line_ends1, line_ends2, s1, s2); |
| 568 | |
| 569 | NarrowDownInput(&input, &output); |
| 570 | |
| 571 | Comparator::CalculateDifference(&input, &output); |
| 572 | |
| 573 | return output.GetResult(); |
| 574 | } |
| 575 | |
| 576 | |
| 577 | // Unwraps JSValue object, returning its field "value" |
| 578 | static Handle<Object> UnwrapJSValue(Handle<JSValue> jsValue) { |
| 579 | return Handle<Object>(jsValue->value(), jsValue->GetIsolate()); |
| 580 | } |
| 581 | |
| 582 | |
| 583 | // Wraps any object into a OpaqueReference, that will hide the object |
| 584 | // from JavaScript. |
| 585 | static Handle<JSValue> WrapInJSValue(Handle<HeapObject> object) { |
| 586 | Isolate* isolate = object->GetIsolate(); |
| 587 | Handle<JSFunction> constructor = isolate->opaque_reference_function(); |
| 588 | Handle<JSValue> result = |
| 589 | Handle<JSValue>::cast(isolate->factory()->NewJSObject(constructor)); |
| 590 | result->set_value(*object); |
| 591 | return result; |
| 592 | } |
| 593 | |
| 594 | |
| 595 | static Handle<SharedFunctionInfo> UnwrapSharedFunctionInfoFromJSValue( |
| 596 | Handle<JSValue> jsValue) { |
| 597 | Object* shared = jsValue->value(); |
| 598 | CHECK(shared->IsSharedFunctionInfo()); |
| 599 | return Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(shared)); |
| 600 | } |
| 601 | |
| 602 | |
| 603 | static int GetArrayLength(Handle<JSArray> array) { |
| 604 | Object* length = array->length(); |
| 605 | CHECK(length->IsSmi()); |
| 606 | return Smi::cast(length)->value(); |
| 607 | } |
| 608 | |
| 609 | |
| 610 | void FunctionInfoWrapper::SetInitialProperties(Handle<String> name, |
| 611 | int start_position, |
| 612 | int end_position, int param_num, |
| 613 | int literal_count, |
| 614 | int parent_index) { |
| 615 | HandleScope scope(isolate()); |
| 616 | this->SetField(kFunctionNameOffset_, name); |
| 617 | this->SetSmiValueField(kStartPositionOffset_, start_position); |
| 618 | this->SetSmiValueField(kEndPositionOffset_, end_position); |
| 619 | this->SetSmiValueField(kParamNumOffset_, param_num); |
| 620 | this->SetSmiValueField(kLiteralNumOffset_, literal_count); |
| 621 | this->SetSmiValueField(kParentIndexOffset_, parent_index); |
| 622 | } |
| 623 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 624 | void FunctionInfoWrapper::SetFunctionCode(Handle<AbstractCode> function_code, |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 625 | Handle<HeapObject> code_scope_info) { |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 626 | // CompileForLiveEdit must deliver full-codegen code. |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 627 | Handle<JSValue> code_wrapper = WrapInJSValue(function_code); |
| 628 | this->SetField(kCodeOffset_, code_wrapper); |
| 629 | |
| 630 | Handle<JSValue> scope_wrapper = WrapInJSValue(code_scope_info); |
| 631 | this->SetField(kCodeScopeInfoOffset_, scope_wrapper); |
| 632 | } |
| 633 | |
| 634 | |
| 635 | void FunctionInfoWrapper::SetSharedFunctionInfo( |
| 636 | Handle<SharedFunctionInfo> info) { |
| 637 | Handle<JSValue> info_holder = WrapInJSValue(info); |
| 638 | this->SetField(kSharedFunctionInfoOffset_, info_holder); |
| 639 | } |
| 640 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 641 | Handle<AbstractCode> FunctionInfoWrapper::GetFunctionCode() { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 642 | Handle<Object> element = this->GetField(kCodeOffset_); |
| 643 | Handle<JSValue> value_wrapper = Handle<JSValue>::cast(element); |
| 644 | Handle<Object> raw_result = UnwrapJSValue(value_wrapper); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 645 | CHECK(raw_result->IsAbstractCode()); |
| 646 | return Handle<AbstractCode>::cast(raw_result); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 647 | } |
| 648 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 649 | MaybeHandle<TypeFeedbackMetadata> FunctionInfoWrapper::GetFeedbackMetadata() { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 650 | Handle<Object> element = this->GetField(kSharedFunctionInfoOffset_); |
| 651 | if (element->IsJSValue()) { |
| 652 | Handle<JSValue> value_wrapper = Handle<JSValue>::cast(element); |
| 653 | Handle<Object> raw_result = UnwrapJSValue(value_wrapper); |
| 654 | Handle<SharedFunctionInfo> shared = |
| 655 | Handle<SharedFunctionInfo>::cast(raw_result); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 656 | return Handle<TypeFeedbackMetadata>(shared->feedback_metadata(), isolate()); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 657 | } else { |
| 658 | // Scripts may never have a SharedFunctionInfo created. |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 659 | return MaybeHandle<TypeFeedbackMetadata>(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 660 | } |
| 661 | } |
| 662 | |
| 663 | |
| 664 | Handle<Object> FunctionInfoWrapper::GetCodeScopeInfo() { |
| 665 | Handle<Object> element = this->GetField(kCodeScopeInfoOffset_); |
| 666 | return UnwrapJSValue(Handle<JSValue>::cast(element)); |
| 667 | } |
| 668 | |
| 669 | |
| 670 | void SharedInfoWrapper::SetProperties(Handle<String> name, |
| 671 | int start_position, |
| 672 | int end_position, |
| 673 | Handle<SharedFunctionInfo> info) { |
| 674 | HandleScope scope(isolate()); |
| 675 | this->SetField(kFunctionNameOffset_, name); |
| 676 | Handle<JSValue> info_holder = WrapInJSValue(info); |
| 677 | this->SetField(kSharedInfoOffset_, info_holder); |
| 678 | this->SetSmiValueField(kStartPositionOffset_, start_position); |
| 679 | this->SetSmiValueField(kEndPositionOffset_, end_position); |
| 680 | } |
| 681 | |
| 682 | |
| 683 | Handle<SharedFunctionInfo> SharedInfoWrapper::GetInfo() { |
| 684 | Handle<Object> element = this->GetField(kSharedInfoOffset_); |
| 685 | Handle<JSValue> value_wrapper = Handle<JSValue>::cast(element); |
| 686 | return UnwrapSharedFunctionInfoFromJSValue(value_wrapper); |
| 687 | } |
| 688 | |
| 689 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 690 | void LiveEdit::InitializeThreadLocal(Debug* debug) { |
| 691 | debug->thread_local_.frame_drop_mode_ = LiveEdit::FRAMES_UNTOUCHED; |
| 692 | } |
| 693 | |
| 694 | |
| 695 | bool LiveEdit::SetAfterBreakTarget(Debug* debug) { |
| 696 | Code* code = NULL; |
| 697 | Isolate* isolate = debug->isolate_; |
| 698 | switch (debug->thread_local_.frame_drop_mode_) { |
| 699 | case FRAMES_UNTOUCHED: |
| 700 | return false; |
| 701 | case FRAME_DROPPED_IN_DEBUG_SLOT_CALL: |
| 702 | // Debug break slot stub does not return normally, instead it manually |
| 703 | // cleans the stack and jumps. We should patch the jump address. |
| 704 | code = isolate->builtins()->builtin(Builtins::kFrameDropper_LiveEdit); |
| 705 | break; |
| 706 | case FRAME_DROPPED_IN_DIRECT_CALL: |
| 707 | // Nothing to do, after_break_target is not used here. |
| 708 | return true; |
| 709 | case FRAME_DROPPED_IN_RETURN_CALL: |
| 710 | code = isolate->builtins()->builtin(Builtins::kFrameDropper_LiveEdit); |
| 711 | break; |
| 712 | case CURRENTLY_SET_MODE: |
| 713 | UNREACHABLE(); |
| 714 | break; |
| 715 | } |
| 716 | debug->after_break_target_ = code->entry(); |
| 717 | return true; |
| 718 | } |
| 719 | |
| 720 | |
| 721 | MaybeHandle<JSArray> LiveEdit::GatherCompileInfo(Handle<Script> script, |
| 722 | Handle<String> source) { |
| 723 | Isolate* isolate = script->GetIsolate(); |
| 724 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 725 | MaybeHandle<JSArray> infos; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 726 | Handle<Object> original_source = |
| 727 | Handle<Object>(script->source(), isolate); |
| 728 | script->set_source(*source); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 729 | |
| 730 | { |
| 731 | // Creating verbose TryCatch from public API is currently the only way to |
| 732 | // force code save location. We do not use this the object directly. |
| 733 | v8::TryCatch try_catch(reinterpret_cast<v8::Isolate*>(isolate)); |
| 734 | try_catch.SetVerbose(true); |
| 735 | |
| 736 | // A logical 'try' section. |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 737 | infos = Compiler::CompileForLiveEdit(script); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 738 | } |
| 739 | |
| 740 | // A logical 'catch' section. |
| 741 | Handle<JSObject> rethrow_exception; |
| 742 | if (isolate->has_pending_exception()) { |
| 743 | Handle<Object> exception(isolate->pending_exception(), isolate); |
| 744 | MessageLocation message_location = isolate->GetMessageLocation(); |
| 745 | |
| 746 | isolate->clear_pending_message(); |
| 747 | isolate->clear_pending_exception(); |
| 748 | |
| 749 | // If possible, copy positions from message object to exception object. |
| 750 | if (exception->IsJSObject() && !message_location.script().is_null()) { |
| 751 | rethrow_exception = Handle<JSObject>::cast(exception); |
| 752 | |
| 753 | Factory* factory = isolate->factory(); |
| 754 | Handle<String> start_pos_key = factory->InternalizeOneByteString( |
| 755 | STATIC_CHAR_VECTOR("startPosition")); |
| 756 | Handle<String> end_pos_key = |
| 757 | factory->InternalizeOneByteString(STATIC_CHAR_VECTOR("endPosition")); |
| 758 | Handle<String> script_obj_key = |
| 759 | factory->InternalizeOneByteString(STATIC_CHAR_VECTOR("scriptObject")); |
| 760 | Handle<Smi> start_pos( |
| 761 | Smi::FromInt(message_location.start_pos()), isolate); |
| 762 | Handle<Smi> end_pos(Smi::FromInt(message_location.end_pos()), isolate); |
| 763 | Handle<JSObject> script_obj = |
| 764 | Script::GetWrapper(message_location.script()); |
| 765 | Object::SetProperty(rethrow_exception, start_pos_key, start_pos, SLOPPY) |
| 766 | .Assert(); |
| 767 | Object::SetProperty(rethrow_exception, end_pos_key, end_pos, SLOPPY) |
| 768 | .Assert(); |
| 769 | Object::SetProperty(rethrow_exception, script_obj_key, script_obj, SLOPPY) |
| 770 | .Assert(); |
| 771 | } |
| 772 | } |
| 773 | |
| 774 | // A logical 'finally' section. |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 775 | script->set_source(*original_source); |
| 776 | |
| 777 | if (rethrow_exception.is_null()) { |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 778 | return infos.ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 779 | } else { |
| 780 | return isolate->Throw<JSArray>(rethrow_exception); |
| 781 | } |
| 782 | } |
| 783 | |
| 784 | |
| 785 | // Visitor that finds all references to a particular code object, |
| 786 | // including "CODE_TARGET" references in other code objects and replaces |
| 787 | // them on the fly. |
| 788 | class ReplacingVisitor : public ObjectVisitor { |
| 789 | public: |
| 790 | explicit ReplacingVisitor(Code* original, Code* substitution) |
| 791 | : original_(original), substitution_(substitution) { |
| 792 | } |
| 793 | |
| 794 | void VisitPointers(Object** start, Object** end) override { |
| 795 | for (Object** p = start; p < end; p++) { |
| 796 | if (*p == original_) { |
| 797 | *p = substitution_; |
| 798 | } |
| 799 | } |
| 800 | } |
| 801 | |
| 802 | void VisitCodeEntry(Address entry) override { |
| 803 | if (Code::GetObjectFromEntryAddress(entry) == original_) { |
| 804 | Address substitution_entry = substitution_->instruction_start(); |
| 805 | Memory::Address_at(entry) = substitution_entry; |
| 806 | } |
| 807 | } |
| 808 | |
| 809 | void VisitCodeTarget(RelocInfo* rinfo) override { |
| 810 | if (RelocInfo::IsCodeTarget(rinfo->rmode()) && |
| 811 | Code::GetCodeFromTargetAddress(rinfo->target_address()) == original_) { |
| 812 | Address substitution_entry = substitution_->instruction_start(); |
| 813 | rinfo->set_target_address(substitution_entry); |
| 814 | } |
| 815 | } |
| 816 | |
| 817 | void VisitDebugTarget(RelocInfo* rinfo) override { VisitCodeTarget(rinfo); } |
| 818 | |
| 819 | private: |
| 820 | Code* original_; |
| 821 | Code* substitution_; |
| 822 | }; |
| 823 | |
| 824 | |
| 825 | // Finds all references to original and replaces them with substitution. |
| 826 | static void ReplaceCodeObject(Handle<Code> original, |
| 827 | Handle<Code> substitution) { |
| 828 | // Perform a full GC in order to ensure that we are not in the middle of an |
| 829 | // incremental marking phase when we are replacing the code object. |
| 830 | // Since we are not in an incremental marking phase we can write pointers |
| 831 | // to code objects (that are never in new space) without worrying about |
| 832 | // write barriers. |
| 833 | Heap* heap = original->GetHeap(); |
| 834 | HeapIterator iterator(heap); |
| 835 | |
| 836 | DCHECK(!heap->InNewSpace(*substitution)); |
| 837 | |
| 838 | ReplacingVisitor visitor(*original, *substitution); |
| 839 | |
| 840 | // Iterate over all roots. Stack frames may have pointer into original code, |
| 841 | // so temporary replace the pointers with offset numbers |
| 842 | // in prologue/epilogue. |
| 843 | heap->IterateRoots(&visitor, VISIT_ALL); |
| 844 | |
| 845 | // Now iterate over all pointers of all objects, including code_target |
| 846 | // implicit pointers. |
| 847 | for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) { |
| 848 | obj->Iterate(&visitor); |
| 849 | } |
| 850 | } |
| 851 | |
| 852 | |
| 853 | // Patch function literals. |
| 854 | // Name 'literals' is a misnomer. Rather it's a cache for complex object |
| 855 | // boilerplates and for a native context. We must clean cached values. |
| 856 | // Additionally we may need to allocate a new array if number of literals |
| 857 | // changed. |
| 858 | class LiteralFixer { |
| 859 | public: |
| 860 | static void PatchLiterals(FunctionInfoWrapper* compile_info_wrapper, |
| 861 | Handle<SharedFunctionInfo> shared_info, |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 862 | bool feedback_metadata_changed, Isolate* isolate) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 863 | int new_literal_count = compile_info_wrapper->GetLiteralCount(); |
| 864 | int old_literal_count = shared_info->num_literals(); |
| 865 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 866 | if (old_literal_count == new_literal_count && !feedback_metadata_changed) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 867 | // If literal count didn't change, simply go over all functions |
| 868 | // and clear literal arrays. |
| 869 | ClearValuesVisitor visitor; |
| 870 | IterateJSFunctions(shared_info, &visitor); |
| 871 | } else { |
| 872 | // When literal count changes, we have to create new array instances. |
| 873 | // Since we cannot create instances when iterating heap, we should first |
| 874 | // collect all functions and fix their literal arrays. |
| 875 | Handle<FixedArray> function_instances = |
| 876 | CollectJSFunctions(shared_info, isolate); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 877 | Handle<TypeFeedbackMetadata> feedback_metadata( |
| 878 | shared_info->feedback_metadata()); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 879 | |
| 880 | for (int i = 0; i < function_instances->length(); i++) { |
| 881 | Handle<JSFunction> fun(JSFunction::cast(function_instances->get(i))); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 882 | Handle<TypeFeedbackVector> vector = |
| 883 | TypeFeedbackVector::New(isolate, feedback_metadata); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 884 | Handle<LiteralsArray> new_literals = |
| 885 | LiteralsArray::New(isolate, vector, new_literal_count, TENURED); |
| 886 | fun->set_literals(*new_literals); |
| 887 | } |
| 888 | |
| 889 | shared_info->set_num_literals(new_literal_count); |
| 890 | } |
| 891 | } |
| 892 | |
| 893 | private: |
| 894 | // Iterates all function instances in the HEAP that refers to the |
| 895 | // provided shared_info. |
| 896 | template<typename Visitor> |
| 897 | static void IterateJSFunctions(Handle<SharedFunctionInfo> shared_info, |
| 898 | Visitor* visitor) { |
| 899 | HeapIterator iterator(shared_info->GetHeap()); |
| 900 | for (HeapObject* obj = iterator.next(); obj != NULL; |
| 901 | obj = iterator.next()) { |
| 902 | if (obj->IsJSFunction()) { |
| 903 | JSFunction* function = JSFunction::cast(obj); |
| 904 | if (function->shared() == *shared_info) { |
| 905 | visitor->visit(function); |
| 906 | } |
| 907 | } |
| 908 | } |
| 909 | } |
| 910 | |
| 911 | // Finds all instances of JSFunction that refers to the provided shared_info |
| 912 | // and returns array with them. |
| 913 | static Handle<FixedArray> CollectJSFunctions( |
| 914 | Handle<SharedFunctionInfo> shared_info, Isolate* isolate) { |
| 915 | CountVisitor count_visitor; |
| 916 | count_visitor.count = 0; |
| 917 | IterateJSFunctions(shared_info, &count_visitor); |
| 918 | int size = count_visitor.count; |
| 919 | |
| 920 | Handle<FixedArray> result = isolate->factory()->NewFixedArray(size); |
| 921 | if (size > 0) { |
| 922 | CollectVisitor collect_visitor(result); |
| 923 | IterateJSFunctions(shared_info, &collect_visitor); |
| 924 | } |
| 925 | return result; |
| 926 | } |
| 927 | |
| 928 | class ClearValuesVisitor { |
| 929 | public: |
| 930 | void visit(JSFunction* fun) { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 931 | LiteralsArray* literals = fun->literals(); |
| 932 | int len = literals->literals_count(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 933 | for (int j = 0; j < len; j++) { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 934 | literals->set_literal_undefined(j); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 935 | } |
| 936 | } |
| 937 | }; |
| 938 | |
| 939 | class CountVisitor { |
| 940 | public: |
| 941 | void visit(JSFunction* fun) { |
| 942 | count++; |
| 943 | } |
| 944 | int count; |
| 945 | }; |
| 946 | |
| 947 | class CollectVisitor { |
| 948 | public: |
| 949 | explicit CollectVisitor(Handle<FixedArray> output) |
| 950 | : m_output(output), m_pos(0) {} |
| 951 | |
| 952 | void visit(JSFunction* fun) { |
| 953 | m_output->set(m_pos, fun); |
| 954 | m_pos++; |
| 955 | } |
| 956 | private: |
| 957 | Handle<FixedArray> m_output; |
| 958 | int m_pos; |
| 959 | }; |
| 960 | }; |
| 961 | |
| 962 | |
| 963 | // Marks code that shares the same shared function info or has inlined |
| 964 | // code that shares the same function info. |
| 965 | class DependentFunctionMarker: public OptimizedFunctionVisitor { |
| 966 | public: |
| 967 | SharedFunctionInfo* shared_info_; |
| 968 | bool found_; |
| 969 | |
| 970 | explicit DependentFunctionMarker(SharedFunctionInfo* shared_info) |
| 971 | : shared_info_(shared_info), found_(false) { } |
| 972 | |
| 973 | virtual void EnterContext(Context* context) { } // Don't care. |
| 974 | virtual void LeaveContext(Context* context) { } // Don't care. |
| 975 | virtual void VisitFunction(JSFunction* function) { |
| 976 | // It should be guaranteed by the iterator that everything is optimized. |
| 977 | DCHECK(function->code()->kind() == Code::OPTIMIZED_FUNCTION); |
| 978 | if (function->Inlines(shared_info_)) { |
| 979 | // Mark the code for deoptimization. |
| 980 | function->code()->set_marked_for_deoptimization(true); |
| 981 | found_ = true; |
| 982 | } |
| 983 | } |
| 984 | }; |
| 985 | |
| 986 | |
| 987 | static void DeoptimizeDependentFunctions(SharedFunctionInfo* function_info) { |
| 988 | DisallowHeapAllocation no_allocation; |
| 989 | DependentFunctionMarker marker(function_info); |
| 990 | // TODO(titzer): need to traverse all optimized code to find OSR code here. |
| 991 | Deoptimizer::VisitAllOptimizedFunctions(function_info->GetIsolate(), &marker); |
| 992 | |
| 993 | if (marker.found_) { |
| 994 | // Only go through with the deoptimization if something was found. |
| 995 | Deoptimizer::DeoptimizeMarkedCode(function_info->GetIsolate()); |
| 996 | } |
| 997 | } |
| 998 | |
| 999 | |
| 1000 | void LiveEdit::ReplaceFunctionCode( |
| 1001 | Handle<JSArray> new_compile_info_array, |
| 1002 | Handle<JSArray> shared_info_array) { |
| 1003 | Isolate* isolate = new_compile_info_array->GetIsolate(); |
| 1004 | |
| 1005 | FunctionInfoWrapper compile_info_wrapper(new_compile_info_array); |
| 1006 | SharedInfoWrapper shared_info_wrapper(shared_info_array); |
| 1007 | |
| 1008 | Handle<SharedFunctionInfo> shared_info = shared_info_wrapper.GetInfo(); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1009 | bool feedback_metadata_changed = false; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1010 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1011 | if (shared_info->is_compiled()) { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1012 | Handle<AbstractCode> new_code = compile_info_wrapper.GetFunctionCode(); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1013 | if (shared_info->HasBytecodeArray()) { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1014 | DCHECK(new_code->IsBytecodeArray()); |
| 1015 | // The old code is interpreted, the new code must be interpreted as well. |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1016 | shared_info->ClearBytecodeArray(); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1017 | shared_info->set_bytecode_array(BytecodeArray::cast(*new_code)); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1018 | } else { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1019 | Handle<Code> old_code(shared_info->code()); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1020 | DCHECK(old_code->kind() == Code::FUNCTION); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1021 | DCHECK(new_code->kind() == AbstractCode::FUNCTION); |
| 1022 | ReplaceCodeObject(old_code, Handle<Code>::cast(new_code)); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1023 | } |
| 1024 | if (shared_info->HasDebugInfo()) { |
| 1025 | // Existing break points will be re-applied. Reset the debug info here. |
| 1026 | isolate->debug()->RemoveDebugInfoAndClearFromShared( |
| 1027 | handle(shared_info->GetDebugInfo())); |
| 1028 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1029 | Handle<Object> code_scope_info = compile_info_wrapper.GetCodeScopeInfo(); |
| 1030 | if (code_scope_info->IsFixedArray()) { |
| 1031 | shared_info->set_scope_info(ScopeInfo::cast(*code_scope_info)); |
| 1032 | } |
| 1033 | shared_info->DisableOptimization(kLiveEdit); |
| 1034 | // Update the type feedback vector, if needed. |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1035 | MaybeHandle<TypeFeedbackMetadata> feedback_metadata = |
| 1036 | compile_info_wrapper.GetFeedbackMetadata(); |
| 1037 | if (!feedback_metadata.is_null()) { |
| 1038 | Handle<TypeFeedbackMetadata> checked_feedback_metadata = |
| 1039 | feedback_metadata.ToHandleChecked(); |
| 1040 | feedback_metadata_changed = checked_feedback_metadata->DiffersFrom( |
| 1041 | shared_info->feedback_metadata()); |
| 1042 | shared_info->set_feedback_metadata(*checked_feedback_metadata); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1043 | } |
| 1044 | } |
| 1045 | |
| 1046 | int start_position = compile_info_wrapper.GetStartPosition(); |
| 1047 | int end_position = compile_info_wrapper.GetEndPosition(); |
| 1048 | shared_info->set_start_position(start_position); |
| 1049 | shared_info->set_end_position(end_position); |
| 1050 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1051 | LiteralFixer::PatchLiterals(&compile_info_wrapper, shared_info, |
| 1052 | feedback_metadata_changed, isolate); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1053 | |
| 1054 | DeoptimizeDependentFunctions(*shared_info); |
| 1055 | isolate->compilation_cache()->Remove(shared_info); |
| 1056 | } |
| 1057 | |
| 1058 | |
| 1059 | void LiveEdit::FunctionSourceUpdated(Handle<JSArray> shared_info_array) { |
| 1060 | SharedInfoWrapper shared_info_wrapper(shared_info_array); |
| 1061 | Handle<SharedFunctionInfo> shared_info = shared_info_wrapper.GetInfo(); |
| 1062 | |
| 1063 | DeoptimizeDependentFunctions(*shared_info); |
| 1064 | shared_info_array->GetIsolate()->compilation_cache()->Remove(shared_info); |
| 1065 | } |
| 1066 | |
| 1067 | |
| 1068 | void LiveEdit::SetFunctionScript(Handle<JSValue> function_wrapper, |
| 1069 | Handle<Object> script_handle) { |
| 1070 | Handle<SharedFunctionInfo> shared_info = |
| 1071 | UnwrapSharedFunctionInfoFromJSValue(function_wrapper); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1072 | Isolate* isolate = function_wrapper->GetIsolate(); |
| 1073 | CHECK(script_handle->IsScript() || script_handle->IsUndefined(isolate)); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1074 | SharedFunctionInfo::SetScript(shared_info, script_handle); |
| 1075 | shared_info->DisableOptimization(kLiveEdit); |
| 1076 | |
| 1077 | function_wrapper->GetIsolate()->compilation_cache()->Remove(shared_info); |
| 1078 | } |
| 1079 | |
| 1080 | |
| 1081 | // For a script text change (defined as position_change_array), translates |
| 1082 | // position in unchanged text to position in changed text. |
| 1083 | // Text change is a set of non-overlapping regions in text, that have changed |
| 1084 | // their contents and length. It is specified as array of groups of 3 numbers: |
| 1085 | // (change_begin, change_end, change_end_new_position). |
| 1086 | // Each group describes a change in text; groups are sorted by change_begin. |
| 1087 | // Only position in text beyond any changes may be successfully translated. |
| 1088 | // If a positions is inside some region that changed, result is currently |
| 1089 | // undefined. |
| 1090 | static int TranslatePosition(int original_position, |
| 1091 | Handle<JSArray> position_change_array) { |
| 1092 | int position_diff = 0; |
| 1093 | int array_len = GetArrayLength(position_change_array); |
| 1094 | Isolate* isolate = position_change_array->GetIsolate(); |
| 1095 | // TODO(635): binary search may be used here |
| 1096 | for (int i = 0; i < array_len; i += 3) { |
| 1097 | HandleScope scope(isolate); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1098 | Handle<Object> element = |
| 1099 | JSReceiver::GetElement(isolate, position_change_array, i) |
| 1100 | .ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1101 | CHECK(element->IsSmi()); |
| 1102 | int chunk_start = Handle<Smi>::cast(element)->value(); |
| 1103 | if (original_position < chunk_start) { |
| 1104 | break; |
| 1105 | } |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1106 | element = JSReceiver::GetElement(isolate, position_change_array, i + 1) |
| 1107 | .ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1108 | CHECK(element->IsSmi()); |
| 1109 | int chunk_end = Handle<Smi>::cast(element)->value(); |
| 1110 | // Position mustn't be inside a chunk. |
| 1111 | DCHECK(original_position >= chunk_end); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1112 | element = JSReceiver::GetElement(isolate, position_change_array, i + 2) |
| 1113 | .ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1114 | CHECK(element->IsSmi()); |
| 1115 | int chunk_changed_end = Handle<Smi>::cast(element)->value(); |
| 1116 | position_diff = chunk_changed_end - chunk_end; |
| 1117 | } |
| 1118 | |
| 1119 | return original_position + position_diff; |
| 1120 | } |
| 1121 | |
| 1122 | |
| 1123 | // Auto-growing buffer for writing relocation info code section. This buffer |
| 1124 | // is a simplified version of buffer from Assembler. Unlike Assembler, this |
| 1125 | // class is platform-independent and it works without dealing with instructions. |
| 1126 | // As specified by RelocInfo format, the buffer is filled in reversed order: |
| 1127 | // from upper to lower addresses. |
| 1128 | // It uses NewArray/DeleteArray for memory management. |
| 1129 | class RelocInfoBuffer { |
| 1130 | public: |
| 1131 | RelocInfoBuffer(int buffer_initial_capicity, byte* pc) { |
| 1132 | buffer_size_ = buffer_initial_capicity + kBufferGap; |
| 1133 | buffer_ = NewArray<byte>(buffer_size_); |
| 1134 | |
| 1135 | reloc_info_writer_.Reposition(buffer_ + buffer_size_, pc); |
| 1136 | } |
| 1137 | ~RelocInfoBuffer() { |
| 1138 | DeleteArray(buffer_); |
| 1139 | } |
| 1140 | |
| 1141 | // As specified by RelocInfo format, the buffer is filled in reversed order: |
| 1142 | // from upper to lower addresses. |
| 1143 | void Write(const RelocInfo* rinfo) { |
| 1144 | if (buffer_ + kBufferGap >= reloc_info_writer_.pos()) { |
| 1145 | Grow(); |
| 1146 | } |
| 1147 | reloc_info_writer_.Write(rinfo); |
| 1148 | } |
| 1149 | |
| 1150 | Vector<byte> GetResult() { |
| 1151 | // Return the bytes from pos up to end of buffer. |
| 1152 | int result_size = |
| 1153 | static_cast<int>((buffer_ + buffer_size_) - reloc_info_writer_.pos()); |
| 1154 | return Vector<byte>(reloc_info_writer_.pos(), result_size); |
| 1155 | } |
| 1156 | |
| 1157 | private: |
| 1158 | void Grow() { |
| 1159 | // Compute new buffer size. |
| 1160 | int new_buffer_size; |
| 1161 | if (buffer_size_ < 2 * KB) { |
| 1162 | new_buffer_size = 4 * KB; |
| 1163 | } else { |
| 1164 | new_buffer_size = 2 * buffer_size_; |
| 1165 | } |
| 1166 | // Some internal data structures overflow for very large buffers, |
| 1167 | // they must ensure that kMaximalBufferSize is not too large. |
| 1168 | if (new_buffer_size > kMaximalBufferSize) { |
| 1169 | V8::FatalProcessOutOfMemory("RelocInfoBuffer::GrowBuffer"); |
| 1170 | } |
| 1171 | |
| 1172 | // Set up new buffer. |
| 1173 | byte* new_buffer = NewArray<byte>(new_buffer_size); |
| 1174 | |
| 1175 | // Copy the data. |
| 1176 | int curently_used_size = |
| 1177 | static_cast<int>(buffer_ + buffer_size_ - reloc_info_writer_.pos()); |
| 1178 | MemMove(new_buffer + new_buffer_size - curently_used_size, |
| 1179 | reloc_info_writer_.pos(), curently_used_size); |
| 1180 | |
| 1181 | reloc_info_writer_.Reposition( |
| 1182 | new_buffer + new_buffer_size - curently_used_size, |
| 1183 | reloc_info_writer_.last_pc()); |
| 1184 | |
| 1185 | DeleteArray(buffer_); |
| 1186 | buffer_ = new_buffer; |
| 1187 | buffer_size_ = new_buffer_size; |
| 1188 | } |
| 1189 | |
| 1190 | RelocInfoWriter reloc_info_writer_; |
| 1191 | byte* buffer_; |
| 1192 | int buffer_size_; |
| 1193 | |
| 1194 | static const int kBufferGap = RelocInfoWriter::kMaxSize; |
| 1195 | static const int kMaximalBufferSize = 512*MB; |
| 1196 | }; |
| 1197 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1198 | namespace { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1199 | // Patch positions in code (changes relocation info section) and possibly |
| 1200 | // returns new instance of code. |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1201 | Handle<Code> PatchPositionsInCode(Handle<Code> code, |
| 1202 | Handle<JSArray> position_change_array) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1203 | Isolate* isolate = code->GetIsolate(); |
| 1204 | |
| 1205 | RelocInfoBuffer buffer_writer(code->relocation_size(), |
| 1206 | code->instruction_start()); |
| 1207 | |
| 1208 | { |
| 1209 | for (RelocIterator it(*code); !it.done(); it.next()) { |
| 1210 | RelocInfo* rinfo = it.rinfo(); |
| 1211 | if (RelocInfo::IsPosition(rinfo->rmode())) { |
| 1212 | int position = static_cast<int>(rinfo->data()); |
| 1213 | int new_position = TranslatePosition(position, |
| 1214 | position_change_array); |
| 1215 | if (position != new_position) { |
| 1216 | RelocInfo info_copy(rinfo->isolate(), rinfo->pc(), rinfo->rmode(), |
| 1217 | new_position, NULL); |
| 1218 | buffer_writer.Write(&info_copy); |
| 1219 | continue; |
| 1220 | } |
| 1221 | } |
| 1222 | if (RelocInfo::IsRealRelocMode(rinfo->rmode())) { |
| 1223 | buffer_writer.Write(it.rinfo()); |
| 1224 | } |
| 1225 | } |
| 1226 | } |
| 1227 | |
| 1228 | Vector<byte> buffer = buffer_writer.GetResult(); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1229 | Handle<ByteArray> reloc_info = |
| 1230 | isolate->factory()->NewByteArray(buffer.length(), TENURED); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1231 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1232 | DisallowHeapAllocation no_gc; |
| 1233 | code->set_relocation_info(*reloc_info); |
| 1234 | CopyBytes(code->relocation_start(), buffer.start(), buffer.length()); |
| 1235 | return code; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1236 | } |
| 1237 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1238 | void PatchPositionsInBytecodeArray(Handle<BytecodeArray> bytecode, |
| 1239 | Handle<JSArray> position_change_array) { |
| 1240 | Isolate* isolate = bytecode->GetIsolate(); |
| 1241 | Zone zone(isolate->allocator()); |
| 1242 | interpreter::SourcePositionTableBuilder builder(isolate, &zone); |
| 1243 | |
| 1244 | for (interpreter::SourcePositionTableIterator iterator( |
| 1245 | bytecode->source_position_table()); |
| 1246 | !iterator.done(); iterator.Advance()) { |
| 1247 | int position = iterator.source_position(); |
| 1248 | int new_position = TranslatePosition(position, position_change_array); |
| 1249 | builder.AddPosition(iterator.bytecode_offset(), new_position, |
| 1250 | iterator.is_statement()); |
| 1251 | } |
| 1252 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1253 | Handle<ByteArray> source_position_table = builder.ToSourcePositionTable(); |
| 1254 | bytecode->set_source_position_table(*source_position_table); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1255 | } |
| 1256 | } // namespace |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1257 | |
| 1258 | void LiveEdit::PatchFunctionPositions(Handle<JSArray> shared_info_array, |
| 1259 | Handle<JSArray> position_change_array) { |
| 1260 | SharedInfoWrapper shared_info_wrapper(shared_info_array); |
| 1261 | Handle<SharedFunctionInfo> info = shared_info_wrapper.GetInfo(); |
| 1262 | |
| 1263 | int old_function_start = info->start_position(); |
| 1264 | int new_function_start = TranslatePosition(old_function_start, |
| 1265 | position_change_array); |
| 1266 | int new_function_end = TranslatePosition(info->end_position(), |
| 1267 | position_change_array); |
| 1268 | int new_function_token_pos = |
| 1269 | TranslatePosition(info->function_token_position(), position_change_array); |
| 1270 | |
| 1271 | info->set_start_position(new_function_start); |
| 1272 | info->set_end_position(new_function_end); |
| 1273 | info->set_function_token_position(new_function_token_pos); |
| 1274 | |
| 1275 | if (info->code()->kind() == Code::FUNCTION) { |
| 1276 | // Patch relocation info section of the code. |
| 1277 | Handle<Code> patched_code = PatchPositionsInCode(Handle<Code>(info->code()), |
| 1278 | position_change_array); |
| 1279 | if (*patched_code != info->code()) { |
| 1280 | // Replace all references to the code across the heap. In particular, |
| 1281 | // some stubs may refer to this code and this code may be being executed |
| 1282 | // on stack (it is safe to substitute the code object on stack, because |
| 1283 | // we only change the structure of rinfo and leave instructions |
| 1284 | // untouched). |
| 1285 | ReplaceCodeObject(Handle<Code>(info->code()), patched_code); |
| 1286 | } |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1287 | } else if (info->HasBytecodeArray()) { |
| 1288 | PatchPositionsInBytecodeArray(Handle<BytecodeArray>(info->bytecode_array()), |
| 1289 | position_change_array); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1290 | } |
| 1291 | } |
| 1292 | |
| 1293 | |
| 1294 | static Handle<Script> CreateScriptCopy(Handle<Script> original) { |
| 1295 | Isolate* isolate = original->GetIsolate(); |
| 1296 | |
| 1297 | Handle<String> original_source(String::cast(original->source())); |
| 1298 | Handle<Script> copy = isolate->factory()->NewScript(original_source); |
| 1299 | |
| 1300 | copy->set_name(original->name()); |
| 1301 | copy->set_line_offset(original->line_offset()); |
| 1302 | copy->set_column_offset(original->column_offset()); |
| 1303 | copy->set_type(original->type()); |
| 1304 | copy->set_context_data(original->context_data()); |
| 1305 | copy->set_eval_from_shared(original->eval_from_shared()); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1306 | copy->set_eval_from_position(original->eval_from_position()); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1307 | |
| 1308 | // Copy all the flags, but clear compilation state. |
| 1309 | copy->set_flags(original->flags()); |
| 1310 | copy->set_compilation_state(Script::COMPILATION_STATE_INITIAL); |
| 1311 | |
| 1312 | return copy; |
| 1313 | } |
| 1314 | |
| 1315 | |
| 1316 | Handle<Object> LiveEdit::ChangeScriptSource(Handle<Script> original_script, |
| 1317 | Handle<String> new_source, |
| 1318 | Handle<Object> old_script_name) { |
| 1319 | Isolate* isolate = original_script->GetIsolate(); |
| 1320 | Handle<Object> old_script_object; |
| 1321 | if (old_script_name->IsString()) { |
| 1322 | Handle<Script> old_script = CreateScriptCopy(original_script); |
| 1323 | old_script->set_name(String::cast(*old_script_name)); |
| 1324 | old_script_object = old_script; |
| 1325 | isolate->debug()->OnAfterCompile(old_script); |
| 1326 | } else { |
| 1327 | old_script_object = isolate->factory()->null_value(); |
| 1328 | } |
| 1329 | |
| 1330 | original_script->set_source(*new_source); |
| 1331 | |
| 1332 | // Drop line ends so that they will be recalculated. |
| 1333 | original_script->set_line_ends(isolate->heap()->undefined_value()); |
| 1334 | |
| 1335 | return old_script_object; |
| 1336 | } |
| 1337 | |
| 1338 | |
| 1339 | |
| 1340 | void LiveEdit::ReplaceRefToNestedFunction( |
| 1341 | Handle<JSValue> parent_function_wrapper, |
| 1342 | Handle<JSValue> orig_function_wrapper, |
| 1343 | Handle<JSValue> subst_function_wrapper) { |
| 1344 | |
| 1345 | Handle<SharedFunctionInfo> parent_shared = |
| 1346 | UnwrapSharedFunctionInfoFromJSValue(parent_function_wrapper); |
| 1347 | Handle<SharedFunctionInfo> orig_shared = |
| 1348 | UnwrapSharedFunctionInfoFromJSValue(orig_function_wrapper); |
| 1349 | Handle<SharedFunctionInfo> subst_shared = |
| 1350 | UnwrapSharedFunctionInfoFromJSValue(subst_function_wrapper); |
| 1351 | |
| 1352 | for (RelocIterator it(parent_shared->code()); !it.done(); it.next()) { |
| 1353 | if (it.rinfo()->rmode() == RelocInfo::EMBEDDED_OBJECT) { |
| 1354 | if (it.rinfo()->target_object() == *orig_shared) { |
| 1355 | it.rinfo()->set_target_object(*subst_shared); |
| 1356 | } |
| 1357 | } |
| 1358 | } |
| 1359 | } |
| 1360 | |
| 1361 | |
| 1362 | // Check an activation against list of functions. If there is a function |
| 1363 | // that matches, its status in result array is changed to status argument value. |
| 1364 | static bool CheckActivation(Handle<JSArray> shared_info_array, |
| 1365 | Handle<JSArray> result, |
| 1366 | StackFrame* frame, |
| 1367 | LiveEdit::FunctionPatchabilityStatus status) { |
| 1368 | if (!frame->is_java_script()) return false; |
| 1369 | |
| 1370 | Handle<JSFunction> function(JavaScriptFrame::cast(frame)->function()); |
| 1371 | |
| 1372 | Isolate* isolate = shared_info_array->GetIsolate(); |
| 1373 | int len = GetArrayLength(shared_info_array); |
| 1374 | for (int i = 0; i < len; i++) { |
| 1375 | HandleScope scope(isolate); |
| 1376 | Handle<Object> element = |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1377 | JSReceiver::GetElement(isolate, shared_info_array, i).ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1378 | Handle<JSValue> jsvalue = Handle<JSValue>::cast(element); |
| 1379 | Handle<SharedFunctionInfo> shared = |
| 1380 | UnwrapSharedFunctionInfoFromJSValue(jsvalue); |
| 1381 | |
| 1382 | if (function->Inlines(*shared)) { |
| 1383 | SetElementSloppy(result, i, Handle<Smi>(Smi::FromInt(status), isolate)); |
| 1384 | return true; |
| 1385 | } |
| 1386 | } |
| 1387 | return false; |
| 1388 | } |
| 1389 | |
| 1390 | |
| 1391 | // Iterates over handler chain and removes all elements that are inside |
| 1392 | // frames being dropped. |
| 1393 | static bool FixTryCatchHandler(StackFrame* top_frame, |
| 1394 | StackFrame* bottom_frame) { |
| 1395 | Address* pointer_address = |
| 1396 | &Memory::Address_at(top_frame->isolate()->get_address_from_id( |
| 1397 | Isolate::kHandlerAddress)); |
| 1398 | |
| 1399 | while (*pointer_address < top_frame->sp()) { |
| 1400 | pointer_address = &Memory::Address_at(*pointer_address); |
| 1401 | } |
| 1402 | Address* above_frame_address = pointer_address; |
| 1403 | while (*pointer_address < bottom_frame->fp()) { |
| 1404 | pointer_address = &Memory::Address_at(*pointer_address); |
| 1405 | } |
| 1406 | bool change = *above_frame_address != *pointer_address; |
| 1407 | *above_frame_address = *pointer_address; |
| 1408 | return change; |
| 1409 | } |
| 1410 | |
| 1411 | |
| 1412 | // Initializes an artificial stack frame. The data it contains is used for: |
| 1413 | // a. successful work of frame dropper code which eventually gets control, |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1414 | // b. being compatible with a typed frame structure for various stack |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1415 | // iterators. |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1416 | // Frame structure (conforms to InternalFrame structure): |
| 1417 | // -- function |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1418 | // -- code |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1419 | // -- SMI marker |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1420 | // -- frame base |
| 1421 | static void SetUpFrameDropperFrame(StackFrame* bottom_js_frame, |
| 1422 | Handle<Code> code) { |
| 1423 | DCHECK(bottom_js_frame->is_java_script()); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1424 | Address fp = bottom_js_frame->fp(); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1425 | Memory::Object_at(fp + FrameDropperFrameConstants::kFunctionOffset) = |
| 1426 | Memory::Object_at(fp + StandardFrameConstants::kFunctionOffset); |
| 1427 | Memory::Object_at(fp + FrameDropperFrameConstants::kFrameTypeOffset) = |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1428 | Smi::FromInt(StackFrame::INTERNAL); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1429 | Memory::Object_at(fp + FrameDropperFrameConstants::kCodeOffset) = *code; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1430 | } |
| 1431 | |
| 1432 | |
| 1433 | // Removes specified range of frames from stack. There may be 1 or more |
| 1434 | // frames in range. Anyway the bottom frame is restarted rather than dropped, |
| 1435 | // and therefore has to be a JavaScript frame. |
| 1436 | // Returns error message or NULL. |
| 1437 | static const char* DropFrames(Vector<StackFrame*> frames, int top_frame_index, |
| 1438 | int bottom_js_frame_index, |
| 1439 | LiveEdit::FrameDropMode* mode) { |
| 1440 | if (!LiveEdit::kFrameDropperSupported) { |
| 1441 | return "Stack manipulations are not supported in this architecture."; |
| 1442 | } |
| 1443 | |
| 1444 | StackFrame* pre_top_frame = frames[top_frame_index - 1]; |
| 1445 | StackFrame* top_frame = frames[top_frame_index]; |
| 1446 | StackFrame* bottom_js_frame = frames[bottom_js_frame_index]; |
| 1447 | |
| 1448 | DCHECK(bottom_js_frame->is_java_script()); |
| 1449 | |
| 1450 | // Check the nature of the top frame. |
| 1451 | Isolate* isolate = bottom_js_frame->isolate(); |
| 1452 | Code* pre_top_frame_code = pre_top_frame->LookupCode(); |
| 1453 | bool frame_has_padding = true; |
| 1454 | if (pre_top_frame_code == |
| 1455 | isolate->builtins()->builtin(Builtins::kSlot_DebugBreak)) { |
| 1456 | // OK, we can drop debug break slot. |
| 1457 | *mode = LiveEdit::FRAME_DROPPED_IN_DEBUG_SLOT_CALL; |
| 1458 | } else if (pre_top_frame_code == |
| 1459 | isolate->builtins()->builtin(Builtins::kFrameDropper_LiveEdit)) { |
| 1460 | // OK, we can drop our own code. |
| 1461 | pre_top_frame = frames[top_frame_index - 2]; |
| 1462 | top_frame = frames[top_frame_index - 1]; |
| 1463 | *mode = LiveEdit::CURRENTLY_SET_MODE; |
| 1464 | frame_has_padding = false; |
| 1465 | } else if (pre_top_frame_code == |
| 1466 | isolate->builtins()->builtin(Builtins::kReturn_DebugBreak)) { |
| 1467 | *mode = LiveEdit::FRAME_DROPPED_IN_RETURN_CALL; |
| 1468 | } else if (pre_top_frame_code->kind() == Code::STUB && |
| 1469 | CodeStub::GetMajorKey(pre_top_frame_code) == CodeStub::CEntry) { |
| 1470 | // Entry from our unit tests on 'debugger' statement. |
| 1471 | // It's fine, we support this case. |
| 1472 | *mode = LiveEdit::FRAME_DROPPED_IN_DIRECT_CALL; |
| 1473 | // We don't have a padding from 'debugger' statement call. |
| 1474 | // Here the stub is CEntry, it's not debug-only and can't be padded. |
| 1475 | // If anyone would complain, a proxy padded stub could be added. |
| 1476 | frame_has_padding = false; |
| 1477 | } else if (pre_top_frame->type() == StackFrame::ARGUMENTS_ADAPTOR) { |
| 1478 | // This must be adaptor that remain from the frame dropping that |
| 1479 | // is still on stack. A frame dropper frame must be above it. |
| 1480 | DCHECK(frames[top_frame_index - 2]->LookupCode() == |
| 1481 | isolate->builtins()->builtin(Builtins::kFrameDropper_LiveEdit)); |
| 1482 | pre_top_frame = frames[top_frame_index - 3]; |
| 1483 | top_frame = frames[top_frame_index - 2]; |
| 1484 | *mode = LiveEdit::CURRENTLY_SET_MODE; |
| 1485 | frame_has_padding = false; |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1486 | } else if (pre_top_frame_code->kind() == Code::BYTECODE_HANDLER) { |
| 1487 | // Interpreted bytecode takes up two stack frames, one for the bytecode |
| 1488 | // handler and one for the interpreter entry trampoline. Therefore we shift |
| 1489 | // up by one frame. |
| 1490 | *mode = LiveEdit::FRAME_DROPPED_IN_DIRECT_CALL; |
| 1491 | pre_top_frame = frames[top_frame_index - 2]; |
| 1492 | top_frame = frames[top_frame_index - 1]; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1493 | } else { |
| 1494 | return "Unknown structure of stack above changing function"; |
| 1495 | } |
| 1496 | |
| 1497 | Address unused_stack_top = top_frame->sp(); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1498 | Address unused_stack_bottom = |
| 1499 | bottom_js_frame->fp() - FrameDropperFrameConstants::kFixedFrameSize + |
| 1500 | 2 * kPointerSize; // Bigger address end is exclusive. |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1501 | |
| 1502 | Address* top_frame_pc_address = top_frame->pc_address(); |
| 1503 | |
| 1504 | // top_frame may be damaged below this point. Do not used it. |
| 1505 | DCHECK(!(top_frame = NULL)); |
| 1506 | |
| 1507 | if (unused_stack_top > unused_stack_bottom) { |
| 1508 | if (frame_has_padding) { |
| 1509 | int shortage_bytes = |
| 1510 | static_cast<int>(unused_stack_top - unused_stack_bottom); |
| 1511 | |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1512 | Address padding_start = |
| 1513 | pre_top_frame->fp() - |
| 1514 | (FrameDropperFrameConstants::kFixedFrameSize - kPointerSize); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1515 | |
| 1516 | Address padding_pointer = padding_start; |
| 1517 | Smi* padding_object = Smi::FromInt(LiveEdit::kFramePaddingValue); |
| 1518 | while (Memory::Object_at(padding_pointer) == padding_object) { |
| 1519 | padding_pointer -= kPointerSize; |
| 1520 | } |
| 1521 | int padding_counter = |
| 1522 | Smi::cast(Memory::Object_at(padding_pointer))->value(); |
| 1523 | if (padding_counter * kPointerSize < shortage_bytes) { |
| 1524 | return "Not enough space for frame dropper frame " |
| 1525 | "(even with padding frame)"; |
| 1526 | } |
| 1527 | Memory::Object_at(padding_pointer) = |
| 1528 | Smi::FromInt(padding_counter - shortage_bytes / kPointerSize); |
| 1529 | |
| 1530 | StackFrame* pre_pre_frame = frames[top_frame_index - 2]; |
| 1531 | |
| 1532 | MemMove(padding_start + kPointerSize - shortage_bytes, |
| 1533 | padding_start + kPointerSize, |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1534 | FrameDropperFrameConstants::kFixedFrameSize - kPointerSize); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1535 | |
| 1536 | pre_top_frame->UpdateFp(pre_top_frame->fp() - shortage_bytes); |
| 1537 | pre_pre_frame->SetCallerFp(pre_top_frame->fp()); |
| 1538 | unused_stack_top -= shortage_bytes; |
| 1539 | |
| 1540 | STATIC_ASSERT(sizeof(Address) == kPointerSize); |
| 1541 | top_frame_pc_address -= shortage_bytes / kPointerSize; |
| 1542 | } else { |
| 1543 | return "Not enough space for frame dropper frame"; |
| 1544 | } |
| 1545 | } |
| 1546 | |
| 1547 | // Committing now. After this point we should return only NULL value. |
| 1548 | |
| 1549 | FixTryCatchHandler(pre_top_frame, bottom_js_frame); |
| 1550 | // Make sure FixTryCatchHandler is idempotent. |
| 1551 | DCHECK(!FixTryCatchHandler(pre_top_frame, bottom_js_frame)); |
| 1552 | |
| 1553 | Handle<Code> code = isolate->builtins()->FrameDropper_LiveEdit(); |
| 1554 | *top_frame_pc_address = code->entry(); |
| 1555 | pre_top_frame->SetCallerFp(bottom_js_frame->fp()); |
| 1556 | |
| 1557 | SetUpFrameDropperFrame(bottom_js_frame, code); |
| 1558 | |
| 1559 | for (Address a = unused_stack_top; |
| 1560 | a < unused_stack_bottom; |
| 1561 | a += kPointerSize) { |
| 1562 | Memory::Object_at(a) = Smi::FromInt(0); |
| 1563 | } |
| 1564 | |
| 1565 | return NULL; |
| 1566 | } |
| 1567 | |
| 1568 | |
| 1569 | // Describes a set of call frames that execute any of listed functions. |
| 1570 | // Finding no such frames does not mean error. |
| 1571 | class MultipleFunctionTarget { |
| 1572 | public: |
| 1573 | MultipleFunctionTarget(Handle<JSArray> old_shared_array, |
| 1574 | Handle<JSArray> new_shared_array, |
| 1575 | Handle<JSArray> result) |
| 1576 | : old_shared_array_(old_shared_array), |
| 1577 | new_shared_array_(new_shared_array), |
| 1578 | result_(result) {} |
| 1579 | bool MatchActivation(StackFrame* frame, |
| 1580 | LiveEdit::FunctionPatchabilityStatus status) { |
| 1581 | return CheckActivation(old_shared_array_, result_, frame, status); |
| 1582 | } |
| 1583 | const char* GetNotFoundMessage() const { |
| 1584 | return NULL; |
| 1585 | } |
| 1586 | bool FrameUsesNewTarget(StackFrame* frame) { |
| 1587 | if (!frame->is_java_script()) return false; |
| 1588 | JavaScriptFrame* jsframe = JavaScriptFrame::cast(frame); |
| 1589 | Handle<SharedFunctionInfo> old_shared(jsframe->function()->shared()); |
| 1590 | Isolate* isolate = old_shared->GetIsolate(); |
| 1591 | int len = GetArrayLength(old_shared_array_); |
| 1592 | // Find corresponding new shared function info and return whether it |
| 1593 | // references new.target. |
| 1594 | for (int i = 0; i < len; i++) { |
| 1595 | HandleScope scope(isolate); |
| 1596 | Handle<Object> old_element = |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1597 | JSReceiver::GetElement(isolate, old_shared_array_, i) |
| 1598 | .ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1599 | if (!old_shared.is_identical_to(UnwrapSharedFunctionInfoFromJSValue( |
| 1600 | Handle<JSValue>::cast(old_element)))) { |
| 1601 | continue; |
| 1602 | } |
| 1603 | |
| 1604 | Handle<Object> new_element = |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1605 | JSReceiver::GetElement(isolate, new_shared_array_, i) |
| 1606 | .ToHandleChecked(); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1607 | if (new_element->IsUndefined(isolate)) return false; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1608 | Handle<SharedFunctionInfo> new_shared = |
| 1609 | UnwrapSharedFunctionInfoFromJSValue( |
| 1610 | Handle<JSValue>::cast(new_element)); |
| 1611 | if (new_shared->scope_info()->HasNewTarget()) { |
| 1612 | SetElementSloppy( |
| 1613 | result_, i, |
| 1614 | Handle<Smi>( |
| 1615 | Smi::FromInt( |
| 1616 | LiveEdit::FUNCTION_BLOCKED_NO_NEW_TARGET_ON_RESTART), |
| 1617 | isolate)); |
| 1618 | return true; |
| 1619 | } |
| 1620 | return false; |
| 1621 | } |
| 1622 | return false; |
| 1623 | } |
| 1624 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1625 | void set_status(LiveEdit::FunctionPatchabilityStatus status) { |
| 1626 | Isolate* isolate = old_shared_array_->GetIsolate(); |
| 1627 | int len = GetArrayLength(old_shared_array_); |
| 1628 | for (int i = 0; i < len; ++i) { |
| 1629 | Handle<Object> old_element = |
| 1630 | JSReceiver::GetElement(isolate, result_, i).ToHandleChecked(); |
| 1631 | if (!old_element->IsSmi() || |
| 1632 | Smi::cast(*old_element)->value() == |
| 1633 | LiveEdit::FUNCTION_AVAILABLE_FOR_PATCH) { |
| 1634 | SetElementSloppy(result_, i, |
| 1635 | Handle<Smi>(Smi::FromInt(status), isolate)); |
| 1636 | } |
| 1637 | } |
| 1638 | } |
| 1639 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1640 | private: |
| 1641 | Handle<JSArray> old_shared_array_; |
| 1642 | Handle<JSArray> new_shared_array_; |
| 1643 | Handle<JSArray> result_; |
| 1644 | }; |
| 1645 | |
| 1646 | |
| 1647 | // Drops all call frame matched by target and all frames above them. |
| 1648 | template <typename TARGET> |
| 1649 | static const char* DropActivationsInActiveThreadImpl(Isolate* isolate, |
| 1650 | TARGET& target, // NOLINT |
| 1651 | bool do_drop) { |
| 1652 | Debug* debug = isolate->debug(); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1653 | Zone zone(isolate->allocator()); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1654 | Vector<StackFrame*> frames = CreateStackMap(isolate, &zone); |
| 1655 | |
| 1656 | |
| 1657 | int top_frame_index = -1; |
| 1658 | int frame_index = 0; |
| 1659 | for (; frame_index < frames.length(); frame_index++) { |
| 1660 | StackFrame* frame = frames[frame_index]; |
| 1661 | if (frame->id() == debug->break_frame_id()) { |
| 1662 | top_frame_index = frame_index; |
| 1663 | break; |
| 1664 | } |
| 1665 | if (target.MatchActivation( |
| 1666 | frame, LiveEdit::FUNCTION_BLOCKED_UNDER_NATIVE_CODE)) { |
| 1667 | // We are still above break_frame. It is not a target frame, |
| 1668 | // it is a problem. |
| 1669 | return "Debugger mark-up on stack is not found"; |
| 1670 | } |
| 1671 | } |
| 1672 | |
| 1673 | if (top_frame_index == -1) { |
| 1674 | // We haven't found break frame, but no function is blocking us anyway. |
| 1675 | return target.GetNotFoundMessage(); |
| 1676 | } |
| 1677 | |
| 1678 | bool target_frame_found = false; |
| 1679 | int bottom_js_frame_index = top_frame_index; |
| 1680 | bool non_droppable_frame_found = false; |
| 1681 | LiveEdit::FunctionPatchabilityStatus non_droppable_reason; |
| 1682 | |
| 1683 | for (; frame_index < frames.length(); frame_index++) { |
| 1684 | StackFrame* frame = frames[frame_index]; |
| 1685 | if (frame->is_exit()) { |
| 1686 | non_droppable_frame_found = true; |
| 1687 | non_droppable_reason = LiveEdit::FUNCTION_BLOCKED_UNDER_NATIVE_CODE; |
| 1688 | break; |
| 1689 | } |
| 1690 | if (frame->is_java_script()) { |
| 1691 | SharedFunctionInfo* shared = |
| 1692 | JavaScriptFrame::cast(frame)->function()->shared(); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1693 | if (shared->is_resumable()) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1694 | non_droppable_frame_found = true; |
| 1695 | non_droppable_reason = LiveEdit::FUNCTION_BLOCKED_UNDER_GENERATOR; |
| 1696 | break; |
| 1697 | } |
| 1698 | } |
| 1699 | if (target.MatchActivation( |
| 1700 | frame, LiveEdit::FUNCTION_BLOCKED_ON_ACTIVE_STACK)) { |
| 1701 | target_frame_found = true; |
| 1702 | bottom_js_frame_index = frame_index; |
| 1703 | } |
| 1704 | } |
| 1705 | |
| 1706 | if (non_droppable_frame_found) { |
| 1707 | // There is a C or generator frame on stack. We can't drop C frames, and we |
| 1708 | // can't restart generators. Check that there are no target frames below |
| 1709 | // them. |
| 1710 | for (; frame_index < frames.length(); frame_index++) { |
| 1711 | StackFrame* frame = frames[frame_index]; |
| 1712 | if (frame->is_java_script()) { |
| 1713 | if (target.MatchActivation(frame, non_droppable_reason)) { |
| 1714 | // Fail. |
| 1715 | return NULL; |
| 1716 | } |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 1717 | if (non_droppable_reason == |
| 1718 | LiveEdit::FUNCTION_BLOCKED_UNDER_GENERATOR && |
| 1719 | !target_frame_found) { |
| 1720 | // Fail. |
| 1721 | target.set_status(non_droppable_reason); |
| 1722 | return NULL; |
| 1723 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1724 | } |
| 1725 | } |
| 1726 | } |
| 1727 | |
| 1728 | // We cannot restart a frame that uses new.target. |
| 1729 | if (target.FrameUsesNewTarget(frames[bottom_js_frame_index])) return NULL; |
| 1730 | |
| 1731 | if (!do_drop) { |
| 1732 | // We are in check-only mode. |
| 1733 | return NULL; |
| 1734 | } |
| 1735 | |
| 1736 | if (!target_frame_found) { |
| 1737 | // Nothing to drop. |
| 1738 | return target.GetNotFoundMessage(); |
| 1739 | } |
| 1740 | |
| 1741 | LiveEdit::FrameDropMode drop_mode = LiveEdit::FRAMES_UNTOUCHED; |
| 1742 | const char* error_message = |
| 1743 | DropFrames(frames, top_frame_index, bottom_js_frame_index, &drop_mode); |
| 1744 | |
| 1745 | if (error_message != NULL) { |
| 1746 | return error_message; |
| 1747 | } |
| 1748 | |
| 1749 | // Adjust break_frame after some frames has been dropped. |
| 1750 | StackFrame::Id new_id = StackFrame::NO_ID; |
| 1751 | for (int i = bottom_js_frame_index + 1; i < frames.length(); i++) { |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1752 | if (frames[i]->type() == StackFrame::JAVA_SCRIPT || |
| 1753 | frames[i]->type() == StackFrame::INTERPRETED) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1754 | new_id = frames[i]->id(); |
| 1755 | break; |
| 1756 | } |
| 1757 | } |
| 1758 | debug->FramesHaveBeenDropped(new_id, drop_mode); |
| 1759 | return NULL; |
| 1760 | } |
| 1761 | |
| 1762 | |
| 1763 | // Fills result array with statuses of functions. Modifies the stack |
| 1764 | // removing all listed function if possible and if do_drop is true. |
| 1765 | static const char* DropActivationsInActiveThread( |
| 1766 | Handle<JSArray> old_shared_array, Handle<JSArray> new_shared_array, |
| 1767 | Handle<JSArray> result, bool do_drop) { |
| 1768 | MultipleFunctionTarget target(old_shared_array, new_shared_array, result); |
| 1769 | Isolate* isolate = old_shared_array->GetIsolate(); |
| 1770 | |
| 1771 | const char* message = |
| 1772 | DropActivationsInActiveThreadImpl(isolate, target, do_drop); |
| 1773 | if (message) { |
| 1774 | return message; |
| 1775 | } |
| 1776 | |
| 1777 | int array_len = GetArrayLength(old_shared_array); |
| 1778 | |
| 1779 | // Replace "blocked on active" with "replaced on active" status. |
| 1780 | for (int i = 0; i < array_len; i++) { |
| 1781 | Handle<Object> obj = |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1782 | JSReceiver::GetElement(isolate, result, i).ToHandleChecked(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1783 | if (*obj == Smi::FromInt(LiveEdit::FUNCTION_BLOCKED_ON_ACTIVE_STACK)) { |
| 1784 | Handle<Object> replaced( |
| 1785 | Smi::FromInt(LiveEdit::FUNCTION_REPLACED_ON_ACTIVE_STACK), isolate); |
| 1786 | SetElementSloppy(result, i, replaced); |
| 1787 | } |
| 1788 | } |
| 1789 | return NULL; |
| 1790 | } |
| 1791 | |
| 1792 | |
| 1793 | bool LiveEdit::FindActiveGenerators(Handle<FixedArray> shared_info_array, |
| 1794 | Handle<FixedArray> result, |
| 1795 | int len) { |
| 1796 | Isolate* isolate = shared_info_array->GetIsolate(); |
| 1797 | bool found_suspended_activations = false; |
| 1798 | |
| 1799 | DCHECK_LE(len, result->length()); |
| 1800 | |
| 1801 | FunctionPatchabilityStatus active = FUNCTION_BLOCKED_ACTIVE_GENERATOR; |
| 1802 | |
| 1803 | Heap* heap = isolate->heap(); |
| 1804 | HeapIterator iterator(heap); |
| 1805 | HeapObject* obj = NULL; |
| 1806 | while ((obj = iterator.next()) != NULL) { |
| 1807 | if (!obj->IsJSGeneratorObject()) continue; |
| 1808 | |
| 1809 | JSGeneratorObject* gen = JSGeneratorObject::cast(obj); |
| 1810 | if (gen->is_closed()) continue; |
| 1811 | |
| 1812 | HandleScope scope(isolate); |
| 1813 | |
| 1814 | for (int i = 0; i < len; i++) { |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1815 | Handle<JSValue> jsvalue = Handle<JSValue>::cast( |
| 1816 | FixedArray::get(*shared_info_array, i, isolate)); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1817 | Handle<SharedFunctionInfo> shared = |
| 1818 | UnwrapSharedFunctionInfoFromJSValue(jsvalue); |
| 1819 | |
| 1820 | if (gen->function()->shared() == *shared) { |
| 1821 | result->set(i, Smi::FromInt(active)); |
| 1822 | found_suspended_activations = true; |
| 1823 | } |
| 1824 | } |
| 1825 | } |
| 1826 | |
| 1827 | return found_suspended_activations; |
| 1828 | } |
| 1829 | |
| 1830 | |
| 1831 | class InactiveThreadActivationsChecker : public ThreadVisitor { |
| 1832 | public: |
| 1833 | InactiveThreadActivationsChecker(Handle<JSArray> old_shared_array, |
| 1834 | Handle<JSArray> result) |
| 1835 | : old_shared_array_(old_shared_array), |
| 1836 | result_(result), |
| 1837 | has_blocked_functions_(false) {} |
| 1838 | void VisitThread(Isolate* isolate, ThreadLocalTop* top) { |
| 1839 | for (StackFrameIterator it(isolate, top); !it.done(); it.Advance()) { |
| 1840 | has_blocked_functions_ |= |
| 1841 | CheckActivation(old_shared_array_, result_, it.frame(), |
| 1842 | LiveEdit::FUNCTION_BLOCKED_ON_OTHER_STACK); |
| 1843 | } |
| 1844 | } |
| 1845 | bool HasBlockedFunctions() { |
| 1846 | return has_blocked_functions_; |
| 1847 | } |
| 1848 | |
| 1849 | private: |
| 1850 | Handle<JSArray> old_shared_array_; |
| 1851 | Handle<JSArray> result_; |
| 1852 | bool has_blocked_functions_; |
| 1853 | }; |
| 1854 | |
| 1855 | |
| 1856 | Handle<JSArray> LiveEdit::CheckAndDropActivations( |
| 1857 | Handle<JSArray> old_shared_array, Handle<JSArray> new_shared_array, |
| 1858 | bool do_drop) { |
| 1859 | Isolate* isolate = old_shared_array->GetIsolate(); |
| 1860 | int len = GetArrayLength(old_shared_array); |
| 1861 | |
| 1862 | DCHECK(old_shared_array->HasFastElements()); |
| 1863 | Handle<FixedArray> old_shared_array_elements( |
| 1864 | FixedArray::cast(old_shared_array->elements())); |
| 1865 | |
| 1866 | Handle<JSArray> result = isolate->factory()->NewJSArray(len); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1867 | JSObject::EnsureWritableFastElements(result); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1868 | Handle<FixedArray> result_elements = |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 1869 | handle(FixedArray::cast(result->elements()), isolate); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1870 | |
| 1871 | // Fill the default values. |
| 1872 | for (int i = 0; i < len; i++) { |
| 1873 | FunctionPatchabilityStatus status = FUNCTION_AVAILABLE_FOR_PATCH; |
| 1874 | result_elements->set(i, Smi::FromInt(status)); |
| 1875 | } |
| 1876 | |
| 1877 | // Scan the heap for active generators -- those that are either currently |
| 1878 | // running (as we wouldn't want to restart them, because we don't know where |
| 1879 | // to restart them from) or suspended. Fail if any one corresponds to the set |
| 1880 | // of functions being edited. |
| 1881 | if (FindActiveGenerators(old_shared_array_elements, result_elements, len)) { |
| 1882 | return result; |
| 1883 | } |
| 1884 | |
| 1885 | // Check inactive threads. Fail if some functions are blocked there. |
| 1886 | InactiveThreadActivationsChecker inactive_threads_checker(old_shared_array, |
| 1887 | result); |
| 1888 | isolate->thread_manager()->IterateArchivedThreads( |
| 1889 | &inactive_threads_checker); |
| 1890 | if (inactive_threads_checker.HasBlockedFunctions()) { |
| 1891 | return result; |
| 1892 | } |
| 1893 | |
| 1894 | // Try to drop activations from the current stack. |
| 1895 | const char* error_message = DropActivationsInActiveThread( |
| 1896 | old_shared_array, new_shared_array, result, do_drop); |
| 1897 | if (error_message != NULL) { |
| 1898 | // Add error message as an array extra element. |
| 1899 | Handle<String> str = |
| 1900 | isolate->factory()->NewStringFromAsciiChecked(error_message); |
| 1901 | SetElementSloppy(result, len, str); |
| 1902 | } |
| 1903 | return result; |
| 1904 | } |
| 1905 | |
| 1906 | |
| 1907 | // Describes a single callframe a target. Not finding this frame |
| 1908 | // means an error. |
| 1909 | class SingleFrameTarget { |
| 1910 | public: |
| 1911 | explicit SingleFrameTarget(JavaScriptFrame* frame) |
| 1912 | : m_frame(frame), |
| 1913 | m_saved_status(LiveEdit::FUNCTION_AVAILABLE_FOR_PATCH) {} |
| 1914 | |
| 1915 | bool MatchActivation(StackFrame* frame, |
| 1916 | LiveEdit::FunctionPatchabilityStatus status) { |
| 1917 | if (frame->fp() == m_frame->fp()) { |
| 1918 | m_saved_status = status; |
| 1919 | return true; |
| 1920 | } |
| 1921 | return false; |
| 1922 | } |
| 1923 | const char* GetNotFoundMessage() const { |
| 1924 | return "Failed to found requested frame"; |
| 1925 | } |
| 1926 | LiveEdit::FunctionPatchabilityStatus saved_status() { |
| 1927 | return m_saved_status; |
| 1928 | } |
| 1929 | void set_status(LiveEdit::FunctionPatchabilityStatus status) { |
| 1930 | m_saved_status = status; |
| 1931 | } |
| 1932 | |
| 1933 | bool FrameUsesNewTarget(StackFrame* frame) { |
| 1934 | if (!frame->is_java_script()) return false; |
| 1935 | JavaScriptFrame* jsframe = JavaScriptFrame::cast(frame); |
| 1936 | Handle<SharedFunctionInfo> shared(jsframe->function()->shared()); |
| 1937 | return shared->scope_info()->HasNewTarget(); |
| 1938 | } |
| 1939 | |
| 1940 | private: |
| 1941 | JavaScriptFrame* m_frame; |
| 1942 | LiveEdit::FunctionPatchabilityStatus m_saved_status; |
| 1943 | }; |
| 1944 | |
| 1945 | |
| 1946 | // Finds a drops required frame and all frames above. |
| 1947 | // Returns error message or NULL. |
| 1948 | const char* LiveEdit::RestartFrame(JavaScriptFrame* frame) { |
| 1949 | SingleFrameTarget target(frame); |
| 1950 | |
| 1951 | const char* result = |
| 1952 | DropActivationsInActiveThreadImpl(frame->isolate(), target, true); |
| 1953 | if (result != NULL) { |
| 1954 | return result; |
| 1955 | } |
| 1956 | if (target.saved_status() == LiveEdit::FUNCTION_BLOCKED_UNDER_NATIVE_CODE) { |
| 1957 | return "Function is blocked under native code"; |
| 1958 | } |
| 1959 | if (target.saved_status() == LiveEdit::FUNCTION_BLOCKED_UNDER_GENERATOR) { |
| 1960 | return "Function is blocked under a generator activation"; |
| 1961 | } |
| 1962 | return NULL; |
| 1963 | } |
| 1964 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1965 | Handle<JSArray> LiveEditFunctionTracker::Collect(FunctionLiteral* node, |
| 1966 | Handle<Script> script, |
| 1967 | Zone* zone, Isolate* isolate) { |
| 1968 | LiveEditFunctionTracker visitor(script, zone, isolate); |
| 1969 | visitor.VisitFunctionLiteral(node); |
| 1970 | return visitor.result_; |
| 1971 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1972 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 1973 | LiveEditFunctionTracker::LiveEditFunctionTracker(Handle<Script> script, |
| 1974 | Zone* zone, Isolate* isolate) |
| 1975 | : AstTraversalVisitor(isolate) { |
| 1976 | current_parent_index_ = -1; |
| 1977 | isolate_ = isolate; |
| 1978 | len_ = 0; |
| 1979 | result_ = isolate->factory()->NewJSArray(10); |
| 1980 | script_ = script; |
| 1981 | zone_ = zone; |
| 1982 | } |
| 1983 | |
| 1984 | void LiveEditFunctionTracker::VisitFunctionLiteral(FunctionLiteral* node) { |
| 1985 | Scope* scope = node->scope(); |
| 1986 | |
| 1987 | // FunctionStarted is called in pre-order. |
| 1988 | FunctionStarted(node); |
| 1989 | |
| 1990 | VisitDeclarations(scope->declarations()); |
| 1991 | VisitStatements(node->body()); |
| 1992 | |
| 1993 | // FunctionDone are called in post-order. |
| 1994 | // TODO(jgruber): If required, replace the (linear cost) |
| 1995 | // FindSharedFunctionInfo call with a more efficient implementation. |
| 1996 | Handle<SharedFunctionInfo> info = |
| 1997 | script_->FindSharedFunctionInfo(node).ToHandleChecked(); |
| 1998 | FunctionDone(info, scope); |
| 1999 | } |
| 2000 | |
| 2001 | void LiveEditFunctionTracker::FunctionStarted(FunctionLiteral* fun) { |
| 2002 | HandleScope handle_scope(isolate_); |
| 2003 | FunctionInfoWrapper info = FunctionInfoWrapper::Create(isolate_); |
| 2004 | info.SetInitialProperties(fun->name(), fun->start_position(), |
| 2005 | fun->end_position(), fun->parameter_count(), |
| 2006 | fun->materialized_literal_count(), |
| 2007 | current_parent_index_); |
| 2008 | current_parent_index_ = len_; |
| 2009 | SetElementSloppy(result_, len_, info.GetJSArray()); |
| 2010 | len_++; |
| 2011 | } |
| 2012 | |
| 2013 | // Saves full information about a function: its code, its scope info |
| 2014 | // and a SharedFunctionInfo object. |
| 2015 | void LiveEditFunctionTracker::FunctionDone(Handle<SharedFunctionInfo> shared, |
| 2016 | Scope* scope) { |
| 2017 | HandleScope handle_scope(isolate_); |
| 2018 | FunctionInfoWrapper info = FunctionInfoWrapper::cast( |
| 2019 | *JSReceiver::GetElement(isolate_, result_, current_parent_index_) |
| 2020 | .ToHandleChecked()); |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 2021 | info.SetFunctionCode(Handle<AbstractCode>(shared->abstract_code()), |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 2022 | Handle<HeapObject>(shared->scope_info())); |
| 2023 | info.SetSharedFunctionInfo(shared); |
| 2024 | |
| 2025 | Handle<Object> scope_info_list = SerializeFunctionScope(scope); |
| 2026 | info.SetFunctionScopeInfo(scope_info_list); |
| 2027 | |
| 2028 | current_parent_index_ = info.GetParentIndex(); |
| 2029 | } |
| 2030 | |
| 2031 | Handle<Object> LiveEditFunctionTracker::SerializeFunctionScope(Scope* scope) { |
| 2032 | Handle<JSArray> scope_info_list = isolate_->factory()->NewJSArray(10); |
| 2033 | int scope_info_length = 0; |
| 2034 | |
| 2035 | // Saves some description of scope. It stores name and indexes of |
| 2036 | // variables in the whole scope chain. Null-named slots delimit |
| 2037 | // scopes of this chain. |
| 2038 | Scope* current_scope = scope; |
| 2039 | while (current_scope != NULL) { |
| 2040 | HandleScope handle_scope(isolate_); |
| 2041 | ZoneList<Variable*> stack_list(current_scope->StackLocalCount(), zone_); |
| 2042 | ZoneList<Variable*> context_list(current_scope->ContextLocalCount(), zone_); |
| 2043 | ZoneList<Variable*> globals_list(current_scope->ContextGlobalCount(), |
| 2044 | zone_); |
| 2045 | current_scope->CollectStackAndContextLocals(&stack_list, &context_list, |
| 2046 | &globals_list); |
| 2047 | context_list.Sort(&Variable::CompareIndex); |
| 2048 | |
| 2049 | for (int i = 0; i < context_list.length(); i++) { |
| 2050 | SetElementSloppy(scope_info_list, scope_info_length, |
| 2051 | context_list[i]->name()); |
| 2052 | scope_info_length++; |
| 2053 | SetElementSloppy( |
| 2054 | scope_info_list, scope_info_length, |
| 2055 | Handle<Smi>(Smi::FromInt(context_list[i]->index()), isolate_)); |
| 2056 | scope_info_length++; |
| 2057 | } |
| 2058 | SetElementSloppy(scope_info_list, scope_info_length, |
| 2059 | Handle<Object>(isolate_->heap()->null_value(), isolate_)); |
| 2060 | scope_info_length++; |
| 2061 | |
| 2062 | current_scope = current_scope->outer_scope(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 2063 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 2064 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 2065 | return scope_info_list; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 2066 | } |
| 2067 | |
| 2068 | } // namespace internal |
| 2069 | } // namespace v8 |