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3// modification, are permitted provided that the following conditions are
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27
28#include "v8.h"
29
30#if defined(V8_TARGET_ARCH_X64)
31
32#include "codegen.h"
33#include "deoptimizer.h"
34#include "full-codegen.h"
35#include "safepoint-table.h"
36
37namespace v8 {
38namespace internal {
39
40
41const int Deoptimizer::table_entry_size_ = 10;
42
43
44int Deoptimizer::patch_size() {
45  return Assembler::kCallInstructionLength;
46}
47
48
49void Deoptimizer::DeoptimizeFunction(JSFunction* function) {
50  HandleScope scope;
51  AssertNoAllocation no_allocation;
52
53  if (!function->IsOptimized()) return;
54
55  // Get the optimized code.
56  Code* code = function->code();
57
58  // Invalidate the relocation information, as it will become invalid by the
59  // code patching below, and is not needed any more.
60  code->InvalidateRelocation();
61
62  // For each LLazyBailout instruction insert a absolute call to the
63  // corresponding deoptimization entry, or a short call to an absolute
64  // jump if space is short. The absolute jumps are put in a table just
65  // before the safepoint table (space was allocated there when the Code
66  // object was created, if necessary).
67
68  Address instruction_start = function->code()->instruction_start();
69#ifdef DEBUG
70  Address prev_call_address = NULL;
71#endif
72  DeoptimizationInputData* deopt_data =
73      DeoptimizationInputData::cast(code->deoptimization_data());
74  for (int i = 0; i < deopt_data->DeoptCount(); i++) {
75    if (deopt_data->Pc(i)->value() == -1) continue;
76    // Position where Call will be patched in.
77    Address call_address = instruction_start + deopt_data->Pc(i)->value();
78    // There is room enough to write a long call instruction because we pad
79    // LLazyBailout instructions with nops if necessary.
80    CodePatcher patcher(call_address, Assembler::kCallInstructionLength);
81    patcher.masm()->Call(GetDeoptimizationEntry(i, LAZY), RelocInfo::NONE);
82    ASSERT(prev_call_address == NULL ||
83           call_address >= prev_call_address + patch_size());
84    ASSERT(call_address + patch_size() <= code->instruction_end());
85#ifdef DEBUG
86    prev_call_address = call_address;
87#endif
88  }
89
90  Isolate* isolate = code->GetIsolate();
91
92  // Add the deoptimizing code to the list.
93  DeoptimizingCodeListNode* node = new DeoptimizingCodeListNode(code);
94  DeoptimizerData* data = isolate->deoptimizer_data();
95  node->set_next(data->deoptimizing_code_list_);
96  data->deoptimizing_code_list_ = node;
97
98  // We might be in the middle of incremental marking with compaction.
99  // Tell collector to treat this code object in a special way and
100  // ignore all slots that might have been recorded on it.
101  isolate->heap()->mark_compact_collector()->InvalidateCode(code);
102
103  // Set the code for the function to non-optimized version.
104  function->ReplaceCode(function->shared()->code());
105
106  if (FLAG_trace_deopt) {
107    PrintF("[forced deoptimization: ");
108    function->PrintName();
109    PrintF(" / %" V8PRIxPTR "]\n", reinterpret_cast<intptr_t>(function));
110  }
111}
112
113
114void Deoptimizer::PatchStackCheckCodeAt(Code* unoptimized_code,
115                                        Address pc_after,
116                                        Code* check_code,
117                                        Code* replacement_code) {
118  Address call_target_address = pc_after - kIntSize;
119  ASSERT(check_code->entry() ==
120         Assembler::target_address_at(call_target_address));
121  // The stack check code matches the pattern:
122  //
123  //     cmp rsp, <limit>
124  //     jae ok
125  //     call <stack guard>
126  //     test rax, <loop nesting depth>
127  // ok: ...
128  //
129  // We will patch away the branch so the code is:
130  //
131  //     cmp rsp, <limit>  ;; Not changed
132  //     nop
133  //     nop
134  //     call <on-stack replacment>
135  //     test rax, <loop nesting depth>
136  // ok:
137  //
138  ASSERT(*(call_target_address - 3) == 0x73 &&  // jae
139         *(call_target_address - 2) == 0x07 &&  // offset
140         *(call_target_address - 1) == 0xe8);   // call
141  *(call_target_address - 3) = 0x66;  // 2 byte nop part 1
142  *(call_target_address - 2) = 0x90;  // 2 byte nop part 2
143  Assembler::set_target_address_at(call_target_address,
144                                   replacement_code->entry());
145
146  unoptimized_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
147      unoptimized_code, call_target_address, replacement_code);
148}
149
150
151void Deoptimizer::RevertStackCheckCodeAt(Code* unoptimized_code,
152                                         Address pc_after,
153                                         Code* check_code,
154                                         Code* replacement_code) {
155  Address call_target_address = pc_after - kIntSize;
156  ASSERT(replacement_code->entry() ==
157         Assembler::target_address_at(call_target_address));
158  // Replace the nops from patching (Deoptimizer::PatchStackCheckCode) to
159  // restore the conditional branch.
160  ASSERT(*(call_target_address - 3) == 0x66 &&  // 2 byte nop part 1
161         *(call_target_address - 2) == 0x90 &&  // 2 byte nop part 2
162         *(call_target_address - 1) == 0xe8);   // call
163  *(call_target_address - 3) = 0x73;  // jae
164  *(call_target_address - 2) = 0x07;  // offset
165  Assembler::set_target_address_at(call_target_address,
166                                   check_code->entry());
167
168  check_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
169      unoptimized_code, call_target_address, check_code);
170}
171
172
173static int LookupBailoutId(DeoptimizationInputData* data, unsigned ast_id) {
174  ByteArray* translations = data->TranslationByteArray();
175  int length = data->DeoptCount();
176  for (int i = 0; i < length; i++) {
177    if (static_cast<unsigned>(data->AstId(i)->value()) == ast_id) {
178      TranslationIterator it(translations,  data->TranslationIndex(i)->value());
179      int value = it.Next();
180      ASSERT(Translation::BEGIN == static_cast<Translation::Opcode>(value));
181      // Read the number of frames.
182      value = it.Next();
183      if (value == 1) return i;
184    }
185  }
186  UNREACHABLE();
187  return -1;
188}
189
190
191void Deoptimizer::DoComputeOsrOutputFrame() {
192  DeoptimizationInputData* data = DeoptimizationInputData::cast(
193      optimized_code_->deoptimization_data());
194  unsigned ast_id = data->OsrAstId()->value();
195  // TODO(kasperl): This should not be the bailout_id_. It should be
196  // the ast id. Confusing.
197  ASSERT(bailout_id_ == ast_id);
198
199  int bailout_id = LookupBailoutId(data, ast_id);
200  unsigned translation_index = data->TranslationIndex(bailout_id)->value();
201  ByteArray* translations = data->TranslationByteArray();
202
203  TranslationIterator iterator(translations, translation_index);
204  Translation::Opcode opcode =
205      static_cast<Translation::Opcode>(iterator.Next());
206  ASSERT(Translation::BEGIN == opcode);
207  USE(opcode);
208  int count = iterator.Next();
209  iterator.Skip(1);  // Drop JS frame count.
210  ASSERT(count == 1);
211  USE(count);
212
213  opcode = static_cast<Translation::Opcode>(iterator.Next());
214  USE(opcode);
215  ASSERT(Translation::JS_FRAME == opcode);
216  unsigned node_id = iterator.Next();
217  USE(node_id);
218  ASSERT(node_id == ast_id);
219  JSFunction* function = JSFunction::cast(ComputeLiteral(iterator.Next()));
220  USE(function);
221  ASSERT(function == function_);
222  unsigned height = iterator.Next();
223  unsigned height_in_bytes = height * kPointerSize;
224  USE(height_in_bytes);
225
226  unsigned fixed_size = ComputeFixedSize(function_);
227  unsigned input_frame_size = input_->GetFrameSize();
228  ASSERT(fixed_size + height_in_bytes == input_frame_size);
229
230  unsigned stack_slot_size = optimized_code_->stack_slots() * kPointerSize;
231  unsigned outgoing_height = data->ArgumentsStackHeight(bailout_id)->value();
232  unsigned outgoing_size = outgoing_height * kPointerSize;
233  unsigned output_frame_size = fixed_size + stack_slot_size + outgoing_size;
234  ASSERT(outgoing_size == 0);  // OSR does not happen in the middle of a call.
235
236  if (FLAG_trace_osr) {
237    PrintF("[on-stack replacement: begin 0x%08" V8PRIxPTR " ",
238           reinterpret_cast<intptr_t>(function_));
239    function_->PrintName();
240    PrintF(" => node=%u, frame=%d->%d]\n",
241           ast_id,
242           input_frame_size,
243           output_frame_size);
244  }
245
246  // There's only one output frame in the OSR case.
247  output_count_ = 1;
248  output_ = new FrameDescription*[1];
249  output_[0] = new(output_frame_size) FrameDescription(
250      output_frame_size, function_);
251  output_[0]->SetFrameType(StackFrame::JAVA_SCRIPT);
252
253  // Clear the incoming parameters in the optimized frame to avoid
254  // confusing the garbage collector.
255  unsigned output_offset = output_frame_size - kPointerSize;
256  int parameter_count = function_->shared()->formal_parameter_count() + 1;
257  for (int i = 0; i < parameter_count; ++i) {
258    output_[0]->SetFrameSlot(output_offset, 0);
259    output_offset -= kPointerSize;
260  }
261
262  // Translate the incoming parameters. This may overwrite some of the
263  // incoming argument slots we've just cleared.
264  int input_offset = input_frame_size - kPointerSize;
265  bool ok = true;
266  int limit = input_offset - (parameter_count * kPointerSize);
267  while (ok && input_offset > limit) {
268    ok = DoOsrTranslateCommand(&iterator, &input_offset);
269  }
270
271  // There are no translation commands for the caller's pc and fp, the
272  // context, and the function.  Set them up explicitly.
273  for (int i = StandardFrameConstants::kCallerPCOffset;
274       ok && i >=  StandardFrameConstants::kMarkerOffset;
275       i -= kPointerSize) {
276    intptr_t input_value = input_->GetFrameSlot(input_offset);
277    if (FLAG_trace_osr) {
278      const char* name = "UNKNOWN";
279      switch (i) {
280        case StandardFrameConstants::kCallerPCOffset:
281          name = "caller's pc";
282          break;
283        case StandardFrameConstants::kCallerFPOffset:
284          name = "fp";
285          break;
286        case StandardFrameConstants::kContextOffset:
287          name = "context";
288          break;
289        case StandardFrameConstants::kMarkerOffset:
290          name = "function";
291          break;
292      }
293      PrintF("    [rsp + %d] <- 0x%08" V8PRIxPTR " ; [rsp + %d] "
294             "(fixed part - %s)\n",
295             output_offset,
296             input_value,
297             input_offset,
298             name);
299    }
300    output_[0]->SetFrameSlot(output_offset, input_->GetFrameSlot(input_offset));
301    input_offset -= kPointerSize;
302    output_offset -= kPointerSize;
303  }
304
305  // Translate the rest of the frame.
306  while (ok && input_offset >= 0) {
307    ok = DoOsrTranslateCommand(&iterator, &input_offset);
308  }
309
310  // If translation of any command failed, continue using the input frame.
311  if (!ok) {
312    delete output_[0];
313    output_[0] = input_;
314    output_[0]->SetPc(reinterpret_cast<intptr_t>(from_));
315  } else {
316    // Set up the frame pointer and the context pointer.
317    output_[0]->SetRegister(rbp.code(), input_->GetRegister(rbp.code()));
318    output_[0]->SetRegister(rsi.code(), input_->GetRegister(rsi.code()));
319
320    unsigned pc_offset = data->OsrPcOffset()->value();
321    intptr_t pc = reinterpret_cast<intptr_t>(
322        optimized_code_->entry() + pc_offset);
323    output_[0]->SetPc(pc);
324  }
325  Code* continuation =
326      function->GetIsolate()->builtins()->builtin(Builtins::kNotifyOSR);
327  output_[0]->SetContinuation(
328      reinterpret_cast<intptr_t>(continuation->entry()));
329
330  if (FLAG_trace_osr) {
331    PrintF("[on-stack replacement translation %s: 0x%08" V8PRIxPTR " ",
332           ok ? "finished" : "aborted",
333           reinterpret_cast<intptr_t>(function));
334    function->PrintName();
335    PrintF(" => pc=0x%0" V8PRIxPTR "]\n", output_[0]->GetPc());
336  }
337}
338
339
340void Deoptimizer::DoComputeArgumentsAdaptorFrame(TranslationIterator* iterator,
341                                                 int frame_index) {
342  JSFunction* function = JSFunction::cast(ComputeLiteral(iterator->Next()));
343  unsigned height = iterator->Next();
344  unsigned height_in_bytes = height * kPointerSize;
345  if (FLAG_trace_deopt) {
346    PrintF("  translating arguments adaptor => height=%d\n", height_in_bytes);
347  }
348
349  unsigned fixed_frame_size = ArgumentsAdaptorFrameConstants::kFrameSize;
350  unsigned output_frame_size = height_in_bytes + fixed_frame_size;
351
352  // Allocate and store the output frame description.
353  FrameDescription* output_frame =
354      new(output_frame_size) FrameDescription(output_frame_size, function);
355  output_frame->SetFrameType(StackFrame::ARGUMENTS_ADAPTOR);
356
357  // Arguments adaptor can not be topmost or bottommost.
358  ASSERT(frame_index > 0 && frame_index < output_count_ - 1);
359  ASSERT(output_[frame_index] == NULL);
360  output_[frame_index] = output_frame;
361
362  // The top address of the frame is computed from the previous
363  // frame's top and this frame's size.
364  intptr_t top_address;
365  top_address = output_[frame_index - 1]->GetTop() - output_frame_size;
366  output_frame->SetTop(top_address);
367
368  // Compute the incoming parameter translation.
369  int parameter_count = height;
370  unsigned output_offset = output_frame_size;
371  for (int i = 0; i < parameter_count; ++i) {
372    output_offset -= kPointerSize;
373    DoTranslateCommand(iterator, frame_index, output_offset);
374  }
375
376  // Read caller's PC from the previous frame.
377  output_offset -= kPointerSize;
378  intptr_t callers_pc = output_[frame_index - 1]->GetPc();
379  output_frame->SetFrameSlot(output_offset, callers_pc);
380  if (FLAG_trace_deopt) {
381    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
382           V8PRIxPTR " ; caller's pc\n",
383           top_address + output_offset, output_offset, callers_pc);
384  }
385
386  // Read caller's FP from the previous frame, and set this frame's FP.
387  output_offset -= kPointerSize;
388  intptr_t value = output_[frame_index - 1]->GetFp();
389  output_frame->SetFrameSlot(output_offset, value);
390  intptr_t fp_value = top_address + output_offset;
391  output_frame->SetFp(fp_value);
392  if (FLAG_trace_deopt) {
393    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
394           V8PRIxPTR " ; caller's fp\n",
395           fp_value, output_offset, value);
396  }
397
398  // A marker value is used in place of the context.
399  output_offset -= kPointerSize;
400  intptr_t context = reinterpret_cast<intptr_t>(
401      Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR));
402  output_frame->SetFrameSlot(output_offset, context);
403  if (FLAG_trace_deopt) {
404    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
405           V8PRIxPTR " ; context (adaptor sentinel)\n",
406           top_address + output_offset, output_offset, context);
407  }
408
409  // The function was mentioned explicitly in the ARGUMENTS_ADAPTOR_FRAME.
410  output_offset -= kPointerSize;
411  value = reinterpret_cast<intptr_t>(function);
412  output_frame->SetFrameSlot(output_offset, value);
413  if (FLAG_trace_deopt) {
414    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
415           V8PRIxPTR " ; function\n",
416           top_address + output_offset, output_offset, value);
417  }
418
419  // Number of incoming arguments.
420  output_offset -= kPointerSize;
421  value = reinterpret_cast<intptr_t>(Smi::FromInt(height - 1));
422  output_frame->SetFrameSlot(output_offset, value);
423  if (FLAG_trace_deopt) {
424    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
425           V8PRIxPTR " ; argc (%d)\n",
426           top_address + output_offset, output_offset, value, height - 1);
427  }
428
429  ASSERT(0 == output_offset);
430
431  Builtins* builtins = isolate_->builtins();
432  Code* adaptor_trampoline =
433      builtins->builtin(Builtins::kArgumentsAdaptorTrampoline);
434  intptr_t pc_value = reinterpret_cast<intptr_t>(
435      adaptor_trampoline->instruction_start() +
436      isolate_->heap()->arguments_adaptor_deopt_pc_offset()->value());
437  output_frame->SetPc(pc_value);
438}
439
440
441void Deoptimizer::DoComputeConstructStubFrame(TranslationIterator* iterator,
442                                              int frame_index) {
443  Builtins* builtins = isolate_->builtins();
444  Code* construct_stub = builtins->builtin(Builtins::kJSConstructStubGeneric);
445  JSFunction* function = JSFunction::cast(ComputeLiteral(iterator->Next()));
446  unsigned height = iterator->Next();
447  unsigned height_in_bytes = height * kPointerSize;
448  if (FLAG_trace_deopt) {
449    PrintF("  translating construct stub => height=%d\n", height_in_bytes);
450  }
451
452  unsigned fixed_frame_size = 7 * kPointerSize;
453  unsigned output_frame_size = height_in_bytes + fixed_frame_size;
454
455  // Allocate and store the output frame description.
456  FrameDescription* output_frame =
457      new(output_frame_size) FrameDescription(output_frame_size, function);
458  output_frame->SetFrameType(StackFrame::CONSTRUCT);
459
460  // Construct stub can not be topmost or bottommost.
461  ASSERT(frame_index > 0 && frame_index < output_count_ - 1);
462  ASSERT(output_[frame_index] == NULL);
463  output_[frame_index] = output_frame;
464
465  // The top address of the frame is computed from the previous
466  // frame's top and this frame's size.
467  intptr_t top_address;
468  top_address = output_[frame_index - 1]->GetTop() - output_frame_size;
469  output_frame->SetTop(top_address);
470
471  // Compute the incoming parameter translation.
472  int parameter_count = height;
473  unsigned output_offset = output_frame_size;
474  for (int i = 0; i < parameter_count; ++i) {
475    output_offset -= kPointerSize;
476    DoTranslateCommand(iterator, frame_index, output_offset);
477  }
478
479  // Read caller's PC from the previous frame.
480  output_offset -= kPointerSize;
481  intptr_t callers_pc = output_[frame_index - 1]->GetPc();
482  output_frame->SetFrameSlot(output_offset, callers_pc);
483  if (FLAG_trace_deopt) {
484    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
485           V8PRIxPTR " ; caller's pc\n",
486           top_address + output_offset, output_offset, callers_pc);
487  }
488
489  // Read caller's FP from the previous frame, and set this frame's FP.
490  output_offset -= kPointerSize;
491  intptr_t value = output_[frame_index - 1]->GetFp();
492  output_frame->SetFrameSlot(output_offset, value);
493  intptr_t fp_value = top_address + output_offset;
494  output_frame->SetFp(fp_value);
495  if (FLAG_trace_deopt) {
496    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
497           V8PRIxPTR " ; caller's fp\n",
498           fp_value, output_offset, value);
499  }
500
501  // The context can be gotten from the previous frame.
502  output_offset -= kPointerSize;
503  value = output_[frame_index - 1]->GetContext();
504  output_frame->SetFrameSlot(output_offset, value);
505  if (FLAG_trace_deopt) {
506    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
507           V8PRIxPTR " ; context\n",
508           top_address + output_offset, output_offset, value);
509  }
510
511  // A marker value is used in place of the function.
512  output_offset -= kPointerSize;
513  value = reinterpret_cast<intptr_t>(Smi::FromInt(StackFrame::CONSTRUCT));
514  output_frame->SetFrameSlot(output_offset, value);
515  if (FLAG_trace_deopt) {
516    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
517           V8PRIxPTR " ; function (construct sentinel)\n",
518           top_address + output_offset, output_offset, value);
519  }
520
521  // The output frame reflects a JSConstructStubGeneric frame.
522  output_offset -= kPointerSize;
523  value = reinterpret_cast<intptr_t>(construct_stub);
524  output_frame->SetFrameSlot(output_offset, value);
525  if (FLAG_trace_deopt) {
526    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
527           V8PRIxPTR " ; code object\n",
528           top_address + output_offset, output_offset, value);
529  }
530
531  // Number of incoming arguments.
532  output_offset -= kPointerSize;
533  value = reinterpret_cast<intptr_t>(Smi::FromInt(height - 1));
534  output_frame->SetFrameSlot(output_offset, value);
535  if (FLAG_trace_deopt) {
536    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
537           V8PRIxPTR " ; argc (%d)\n",
538           top_address + output_offset, output_offset, value, height - 1);
539  }
540
541  // The newly allocated object was passed as receiver in the artificial
542  // constructor stub environment created by HEnvironment::CopyForInlining().
543  output_offset -= kPointerSize;
544  value = output_frame->GetFrameSlot(output_frame_size - kPointerSize);
545  output_frame->SetFrameSlot(output_offset, value);
546  if (FLAG_trace_deopt) {
547    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
548           V8PRIxPTR " ; allocated receiver\n",
549           top_address + output_offset, output_offset, value);
550  }
551
552  ASSERT(0 == output_offset);
553
554  intptr_t pc = reinterpret_cast<intptr_t>(
555      construct_stub->instruction_start() +
556      isolate_->heap()->construct_stub_deopt_pc_offset()->value());
557  output_frame->SetPc(pc);
558}
559
560
561void Deoptimizer::DoComputeJSFrame(TranslationIterator* iterator,
562                                   int frame_index) {
563  int node_id = iterator->Next();
564  JSFunction* function = JSFunction::cast(ComputeLiteral(iterator->Next()));
565  unsigned height = iterator->Next();
566  unsigned height_in_bytes = height * kPointerSize;
567  if (FLAG_trace_deopt) {
568    PrintF("  translating ");
569    function->PrintName();
570    PrintF(" => node=%d, height=%d\n", node_id, height_in_bytes);
571  }
572
573  // The 'fixed' part of the frame consists of the incoming parameters and
574  // the part described by JavaScriptFrameConstants.
575  unsigned fixed_frame_size = ComputeFixedSize(function);
576  unsigned input_frame_size = input_->GetFrameSize();
577  unsigned output_frame_size = height_in_bytes + fixed_frame_size;
578
579  // Allocate and store the output frame description.
580  FrameDescription* output_frame =
581      new(output_frame_size) FrameDescription(output_frame_size, function);
582  output_frame->SetFrameType(StackFrame::JAVA_SCRIPT);
583
584  bool is_bottommost = (0 == frame_index);
585  bool is_topmost = (output_count_ - 1 == frame_index);
586  ASSERT(frame_index >= 0 && frame_index < output_count_);
587  ASSERT(output_[frame_index] == NULL);
588  output_[frame_index] = output_frame;
589
590  // The top address for the bottommost output frame can be computed from
591  // the input frame pointer and the output frame's height.  For all
592  // subsequent output frames, it can be computed from the previous one's
593  // top address and the current frame's size.
594  intptr_t top_address;
595  if (is_bottommost) {
596    // 2 = context and function in the frame.
597    top_address =
598        input_->GetRegister(rbp.code()) - (2 * kPointerSize) - height_in_bytes;
599  } else {
600    top_address = output_[frame_index - 1]->GetTop() - output_frame_size;
601  }
602  output_frame->SetTop(top_address);
603
604  // Compute the incoming parameter translation.
605  int parameter_count = function->shared()->formal_parameter_count() + 1;
606  unsigned output_offset = output_frame_size;
607  unsigned input_offset = input_frame_size;
608  for (int i = 0; i < parameter_count; ++i) {
609    output_offset -= kPointerSize;
610    DoTranslateCommand(iterator, frame_index, output_offset);
611  }
612  input_offset -= (parameter_count * kPointerSize);
613
614  // There are no translation commands for the caller's pc and fp, the
615  // context, and the function.  Synthesize their values and set them up
616  // explicitly.
617  //
618  // The caller's pc for the bottommost output frame is the same as in the
619  // input frame.  For all subsequent output frames, it can be read from the
620  // previous one.  This frame's pc can be computed from the non-optimized
621  // function code and AST id of the bailout.
622  output_offset -= kPointerSize;
623  input_offset -= kPointerSize;
624  intptr_t value;
625  if (is_bottommost) {
626    value = input_->GetFrameSlot(input_offset);
627  } else {
628    value = output_[frame_index - 1]->GetPc();
629  }
630  output_frame->SetFrameSlot(output_offset, value);
631  if (FLAG_trace_deopt) {
632    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
633           V8PRIxPTR  " ; caller's pc\n",
634           top_address + output_offset, output_offset, value);
635  }
636
637  // The caller's frame pointer for the bottommost output frame is the same
638  // as in the input frame.  For all subsequent output frames, it can be
639  // read from the previous one.  Also compute and set this frame's frame
640  // pointer.
641  output_offset -= kPointerSize;
642  input_offset -= kPointerSize;
643  if (is_bottommost) {
644    value = input_->GetFrameSlot(input_offset);
645  } else {
646    value = output_[frame_index - 1]->GetFp();
647  }
648  output_frame->SetFrameSlot(output_offset, value);
649  intptr_t fp_value = top_address + output_offset;
650  ASSERT(!is_bottommost || input_->GetRegister(rbp.code()) == fp_value);
651  output_frame->SetFp(fp_value);
652  if (is_topmost) output_frame->SetRegister(rbp.code(), fp_value);
653  if (FLAG_trace_deopt) {
654    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
655           V8PRIxPTR " ; caller's fp\n",
656           fp_value, output_offset, value);
657  }
658
659  // For the bottommost output frame the context can be gotten from the input
660  // frame. For all subsequent output frames it can be gotten from the function
661  // so long as we don't inline functions that need local contexts.
662  output_offset -= kPointerSize;
663  input_offset -= kPointerSize;
664  if (is_bottommost) {
665    value = input_->GetFrameSlot(input_offset);
666  } else {
667    value = reinterpret_cast<intptr_t>(function->context());
668  }
669  output_frame->SetFrameSlot(output_offset, value);
670  output_frame->SetContext(value);
671  if (is_topmost) output_frame->SetRegister(rsi.code(), value);
672  if (FLAG_trace_deopt) {
673    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
674           V8PRIxPTR "; context\n",
675           top_address + output_offset, output_offset, value);
676  }
677
678  // The function was mentioned explicitly in the BEGIN_FRAME.
679  output_offset -= kPointerSize;
680  input_offset -= kPointerSize;
681  value = reinterpret_cast<intptr_t>(function);
682  // The function for the bottommost output frame should also agree with the
683  // input frame.
684  ASSERT(!is_bottommost || input_->GetFrameSlot(input_offset) == value);
685  output_frame->SetFrameSlot(output_offset, value);
686  if (FLAG_trace_deopt) {
687    PrintF("    0x%08" V8PRIxPTR ": [top + %d] <- 0x%08"
688           V8PRIxPTR "; function\n",
689           top_address + output_offset, output_offset, value);
690  }
691
692  // Translate the rest of the frame.
693  for (unsigned i = 0; i < height; ++i) {
694    output_offset -= kPointerSize;
695    DoTranslateCommand(iterator, frame_index, output_offset);
696  }
697  ASSERT(0 == output_offset);
698
699  // Compute this frame's PC, state, and continuation.
700  Code* non_optimized_code = function->shared()->code();
701  FixedArray* raw_data = non_optimized_code->deoptimization_data();
702  DeoptimizationOutputData* data = DeoptimizationOutputData::cast(raw_data);
703  Address start = non_optimized_code->instruction_start();
704  unsigned pc_and_state = GetOutputInfo(data, node_id, function->shared());
705  unsigned pc_offset = FullCodeGenerator::PcField::decode(pc_and_state);
706  intptr_t pc_value = reinterpret_cast<intptr_t>(start + pc_offset);
707  output_frame->SetPc(pc_value);
708
709  FullCodeGenerator::State state =
710      FullCodeGenerator::StateField::decode(pc_and_state);
711  output_frame->SetState(Smi::FromInt(state));
712
713  // Set the continuation for the topmost frame.
714  if (is_topmost && bailout_type_ != DEBUGGER) {
715    Code* continuation = (bailout_type_ == EAGER)
716        ? isolate_->builtins()->builtin(Builtins::kNotifyDeoptimized)
717        : isolate_->builtins()->builtin(Builtins::kNotifyLazyDeoptimized);
718    output_frame->SetContinuation(
719        reinterpret_cast<intptr_t>(continuation->entry()));
720  }
721}
722
723
724void Deoptimizer::FillInputFrame(Address tos, JavaScriptFrame* frame) {
725  // Set the register values. The values are not important as there are no
726  // callee saved registers in JavaScript frames, so all registers are
727  // spilled. Registers rbp and rsp are set to the correct values though.
728  for (int i = 0; i < Register::kNumRegisters; i++) {
729    input_->SetRegister(i, i * 4);
730  }
731  input_->SetRegister(rsp.code(), reinterpret_cast<intptr_t>(frame->sp()));
732  input_->SetRegister(rbp.code(), reinterpret_cast<intptr_t>(frame->fp()));
733  for (int i = 0; i < DoubleRegister::kNumAllocatableRegisters; i++) {
734    input_->SetDoubleRegister(i, 0.0);
735  }
736
737  // Fill the frame content from the actual data on the frame.
738  for (unsigned i = 0; i < input_->GetFrameSize(); i += kPointerSize) {
739    input_->SetFrameSlot(i, Memory::uint64_at(tos + i));
740  }
741}
742
743
744#define __ masm()->
745
746void Deoptimizer::EntryGenerator::Generate() {
747  GeneratePrologue();
748
749  // Save all general purpose registers before messing with them.
750  const int kNumberOfRegisters = Register::kNumRegisters;
751
752  const int kDoubleRegsSize = kDoubleSize *
753                              XMMRegister::kNumAllocatableRegisters;
754  __ subq(rsp, Immediate(kDoubleRegsSize));
755
756  for (int i = 0; i < XMMRegister::kNumAllocatableRegisters; ++i) {
757    XMMRegister xmm_reg = XMMRegister::FromAllocationIndex(i);
758    int offset = i * kDoubleSize;
759    __ movsd(Operand(rsp, offset), xmm_reg);
760  }
761
762  // We push all registers onto the stack, even though we do not need
763  // to restore all later.
764  for (int i = 0; i < kNumberOfRegisters; i++) {
765    Register r = Register::from_code(i);
766    __ push(r);
767  }
768
769  const int kSavedRegistersAreaSize = kNumberOfRegisters * kPointerSize +
770                                      kDoubleRegsSize;
771
772  // When calling new_deoptimizer_function we need to pass the last argument
773  // on the stack on windows and in r8 on linux. The remaining arguments are
774  // all passed in registers (different ones on linux and windows though).
775
776#ifdef _WIN64
777  Register arg4 = r9;
778  Register arg3 = r8;
779  Register arg2 = rdx;
780  Register arg1 = rcx;
781#else
782  Register arg4 = rcx;
783  Register arg3 = rdx;
784  Register arg2 = rsi;
785  Register arg1 = rdi;
786#endif
787
788  // We use this to keep the value of the fifth argument temporarily.
789  // Unfortunately we can't store it directly in r8 (used for passing
790  // this on linux), since it is another parameter passing register on windows.
791  Register arg5 = r11;
792
793  // Get the bailout id from the stack.
794  __ movq(arg3, Operand(rsp, kSavedRegistersAreaSize));
795
796  // Get the address of the location in the code object if possible
797  // and compute the fp-to-sp delta in register arg5.
798  if (type() == EAGER) {
799    __ Set(arg4, 0);
800    __ lea(arg5, Operand(rsp, kSavedRegistersAreaSize + 1 * kPointerSize));
801  } else {
802    __ movq(arg4, Operand(rsp, kSavedRegistersAreaSize + 1 * kPointerSize));
803    __ lea(arg5, Operand(rsp, kSavedRegistersAreaSize + 2 * kPointerSize));
804  }
805
806  __ subq(arg5, rbp);
807  __ neg(arg5);
808
809  // Allocate a new deoptimizer object.
810  __ PrepareCallCFunction(6);
811  __ movq(rax, Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));
812  __ movq(arg1, rax);
813  __ Set(arg2, type());
814  // Args 3 and 4 are already in the right registers.
815
816  // On windows put the arguments on the stack (PrepareCallCFunction
817  // has created space for this). On linux pass the arguments in r8 and r9.
818#ifdef _WIN64
819  __ movq(Operand(rsp, 4 * kPointerSize), arg5);
820  __ LoadAddress(arg5, ExternalReference::isolate_address());
821  __ movq(Operand(rsp, 5 * kPointerSize), arg5);
822#else
823  __ movq(r8, arg5);
824  __ LoadAddress(r9, ExternalReference::isolate_address());
825#endif
826
827  Isolate* isolate = masm()->isolate();
828
829  {
830    AllowExternalCallThatCantCauseGC scope(masm());
831    __ CallCFunction(ExternalReference::new_deoptimizer_function(isolate), 6);
832  }
833  // Preserve deoptimizer object in register rax and get the input
834  // frame descriptor pointer.
835  __ movq(rbx, Operand(rax, Deoptimizer::input_offset()));
836
837  // Fill in the input registers.
838  for (int i = kNumberOfRegisters -1; i >= 0; i--) {
839    int offset = (i * kPointerSize) + FrameDescription::registers_offset();
840    __ pop(Operand(rbx, offset));
841  }
842
843  // Fill in the double input registers.
844  int double_regs_offset = FrameDescription::double_registers_offset();
845  for (int i = 0; i < XMMRegister::kNumAllocatableRegisters; i++) {
846    int dst_offset = i * kDoubleSize + double_regs_offset;
847    __ pop(Operand(rbx, dst_offset));
848  }
849
850  // Remove the bailout id from the stack.
851  if (type() == EAGER) {
852    __ addq(rsp, Immediate(kPointerSize));
853  } else {
854    __ addq(rsp, Immediate(2 * kPointerSize));
855  }
856
857  // Compute a pointer to the unwinding limit in register rcx; that is
858  // the first stack slot not part of the input frame.
859  __ movq(rcx, Operand(rbx, FrameDescription::frame_size_offset()));
860  __ addq(rcx, rsp);
861
862  // Unwind the stack down to - but not including - the unwinding
863  // limit and copy the contents of the activation frame to the input
864  // frame description.
865  __ lea(rdx, Operand(rbx, FrameDescription::frame_content_offset()));
866  Label pop_loop;
867  __ bind(&pop_loop);
868  __ pop(Operand(rdx, 0));
869  __ addq(rdx, Immediate(sizeof(intptr_t)));
870  __ cmpq(rcx, rsp);
871  __ j(not_equal, &pop_loop);
872
873  // Compute the output frame in the deoptimizer.
874  __ push(rax);
875  __ PrepareCallCFunction(2);
876  __ movq(arg1, rax);
877  __ LoadAddress(arg2, ExternalReference::isolate_address());
878  {
879    AllowExternalCallThatCantCauseGC scope(masm());
880    __ CallCFunction(
881        ExternalReference::compute_output_frames_function(isolate), 2);
882  }
883  __ pop(rax);
884
885  // Replace the current frame with the output frames.
886  Label outer_push_loop, inner_push_loop;
887  // Outer loop state: rax = current FrameDescription**, rdx = one past the
888  // last FrameDescription**.
889  __ movl(rdx, Operand(rax, Deoptimizer::output_count_offset()));
890  __ movq(rax, Operand(rax, Deoptimizer::output_offset()));
891  __ lea(rdx, Operand(rax, rdx, times_8, 0));
892  __ bind(&outer_push_loop);
893  // Inner loop state: rbx = current FrameDescription*, rcx = loop index.
894  __ movq(rbx, Operand(rax, 0));
895  __ movq(rcx, Operand(rbx, FrameDescription::frame_size_offset()));
896  __ bind(&inner_push_loop);
897  __ subq(rcx, Immediate(sizeof(intptr_t)));
898  __ push(Operand(rbx, rcx, times_1, FrameDescription::frame_content_offset()));
899  __ testq(rcx, rcx);
900  __ j(not_zero, &inner_push_loop);
901  __ addq(rax, Immediate(kPointerSize));
902  __ cmpq(rax, rdx);
903  __ j(below, &outer_push_loop);
904
905  // In case of OSR, we have to restore the XMM registers.
906  if (type() == OSR) {
907    for (int i = 0; i < XMMRegister::kNumAllocatableRegisters; ++i) {
908      XMMRegister xmm_reg = XMMRegister::FromAllocationIndex(i);
909      int src_offset = i * kDoubleSize + double_regs_offset;
910      __ movsd(xmm_reg, Operand(rbx, src_offset));
911    }
912  }
913
914  // Push state, pc, and continuation from the last output frame.
915  if (type() != OSR) {
916    __ push(Operand(rbx, FrameDescription::state_offset()));
917  }
918  __ push(Operand(rbx, FrameDescription::pc_offset()));
919  __ push(Operand(rbx, FrameDescription::continuation_offset()));
920
921  // Push the registers from the last output frame.
922  for (int i = 0; i < kNumberOfRegisters; i++) {
923    int offset = (i * kPointerSize) + FrameDescription::registers_offset();
924    __ push(Operand(rbx, offset));
925  }
926
927  // Restore the registers from the stack.
928  for (int i = kNumberOfRegisters - 1; i >= 0 ; i--) {
929    Register r = Register::from_code(i);
930    // Do not restore rsp, simply pop the value into the next register
931    // and overwrite this afterwards.
932    if (r.is(rsp)) {
933      ASSERT(i > 0);
934      r = Register::from_code(i - 1);
935    }
936    __ pop(r);
937  }
938
939  // Set up the roots register.
940  __ InitializeRootRegister();
941  __ InitializeSmiConstantRegister();
942
943  // Return to the continuation point.
944  __ ret(0);
945}
946
947
948void Deoptimizer::TableEntryGenerator::GeneratePrologue() {
949  // Create a sequence of deoptimization entries.
950  Label done;
951  for (int i = 0; i < count(); i++) {
952    int start = masm()->pc_offset();
953    USE(start);
954    __ push_imm32(i);
955    __ jmp(&done);
956    ASSERT(masm()->pc_offset() - start == table_entry_size_);
957  }
958  __ bind(&done);
959}
960
961#undef __
962
963
964} }  // namespace v8::internal
965
966#endif  // V8_TARGET_ARCH_X64
967