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      1 // Copyright 2006-2008 the V8 project authors. All rights reserved.
      2 // Redistribution and use in source and binary forms, with or without
      3 // modification, are permitted provided that the following conditions are
      4 // met:
      5 //
      6 //     * Redistributions of source code must retain the above copyright
      7 //       notice, this list of conditions and the following disclaimer.
      8 //     * Redistributions in binary form must reproduce the above
      9 //       copyright notice, this list of conditions and the following
     10 //       disclaimer in the documentation and/or other materials provided
     11 //       with the distribution.
     12 //     * Neither the name of Google Inc. nor the names of its
     13 //       contributors may be used to endorse or promote products derived
     14 //       from this software without specific prior written permission.
     15 //
     16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27 
     28 #include "v8.h"
     29 
     30 #include "ast.h"
     31 #include "deoptimizer.h"
     32 #include "frames-inl.h"
     33 #include "full-codegen.h"
     34 #include "mark-compact.h"
     35 #include "safepoint-table.h"
     36 #include "scopeinfo.h"
     37 #include "string-stream.h"
     38 
     39 namespace v8 {
     40 namespace internal {
     41 
     42 // Iterator that supports traversing the stack handlers of a
     43 // particular frame. Needs to know the top of the handler chain.
     44 class StackHandlerIterator BASE_EMBEDDED {
     45  public:
     46   StackHandlerIterator(const StackFrame* frame, StackHandler* handler)
     47       : limit_(frame->fp()), handler_(handler) {
     48     // Make sure the handler has already been unwound to this frame.
     49     ASSERT(frame->sp() <= handler->address());
     50   }
     51 
     52   StackHandler* handler() const { return handler_; }
     53 
     54   bool done() {
     55     return handler_ == NULL || handler_->address() > limit_;
     56   }
     57   void Advance() {
     58     ASSERT(!done());
     59     handler_ = handler_->next();
     60   }
     61 
     62  private:
     63   const Address limit_;
     64   StackHandler* handler_;
     65 };
     66 
     67 
     68 // -------------------------------------------------------------------------
     69 
     70 
     71 #define INITIALIZE_SINGLETON(type, field) field##_(this),
     72 StackFrameIterator::StackFrameIterator()
     73     : isolate_(Isolate::Current()),
     74       STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
     75       frame_(NULL), handler_(NULL),
     76       thread_(isolate_->thread_local_top()),
     77       fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
     78   Reset();
     79 }
     80 StackFrameIterator::StackFrameIterator(Isolate* isolate)
     81     : isolate_(isolate),
     82       STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
     83       frame_(NULL), handler_(NULL),
     84       thread_(isolate_->thread_local_top()),
     85       fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
     86   Reset();
     87 }
     88 StackFrameIterator::StackFrameIterator(Isolate* isolate, ThreadLocalTop* t)
     89     : isolate_(isolate),
     90       STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
     91       frame_(NULL), handler_(NULL), thread_(t),
     92       fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
     93   Reset();
     94 }
     95 StackFrameIterator::StackFrameIterator(Isolate* isolate,
     96                                        bool use_top, Address fp, Address sp)
     97     : isolate_(isolate),
     98       STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
     99       frame_(NULL), handler_(NULL),
    100       thread_(use_top ? isolate_->thread_local_top() : NULL),
    101       fp_(use_top ? NULL : fp), sp_(sp),
    102       advance_(use_top ? &StackFrameIterator::AdvanceWithHandler :
    103                &StackFrameIterator::AdvanceWithoutHandler) {
    104   if (use_top || fp != NULL) {
    105     Reset();
    106   }
    107 }
    108 
    109 #undef INITIALIZE_SINGLETON
    110 
    111 
    112 void StackFrameIterator::AdvanceWithHandler() {
    113   ASSERT(!done());
    114   // Compute the state of the calling frame before restoring
    115   // callee-saved registers and unwinding handlers. This allows the
    116   // frame code that computes the caller state to access the top
    117   // handler and the value of any callee-saved register if needed.
    118   StackFrame::State state;
    119   StackFrame::Type type = frame_->GetCallerState(&state);
    120 
    121   // Unwind handlers corresponding to the current frame.
    122   StackHandlerIterator it(frame_, handler_);
    123   while (!it.done()) it.Advance();
    124   handler_ = it.handler();
    125 
    126   // Advance to the calling frame.
    127   frame_ = SingletonFor(type, &state);
    128 
    129   // When we're done iterating over the stack frames, the handler
    130   // chain must have been completely unwound.
    131   ASSERT(!done() || handler_ == NULL);
    132 }
    133 
    134 
    135 void StackFrameIterator::AdvanceWithoutHandler() {
    136   // A simpler version of Advance which doesn't care about handler.
    137   ASSERT(!done());
    138   StackFrame::State state;
    139   StackFrame::Type type = frame_->GetCallerState(&state);
    140   frame_ = SingletonFor(type, &state);
    141 }
    142 
    143 
    144 void StackFrameIterator::Reset() {
    145   StackFrame::State state;
    146   StackFrame::Type type;
    147   if (thread_ != NULL) {
    148     type = ExitFrame::GetStateForFramePointer(
    149         Isolate::c_entry_fp(thread_), &state);
    150     handler_ = StackHandler::FromAddress(
    151         Isolate::handler(thread_));
    152   } else {
    153     ASSERT(fp_ != NULL);
    154     state.fp = fp_;
    155     state.sp = sp_;
    156     state.pc_address =
    157         reinterpret_cast<Address*>(StandardFrame::ComputePCAddress(fp_));
    158     type = StackFrame::ComputeType(isolate(), &state);
    159   }
    160   if (SingletonFor(type) == NULL) return;
    161   frame_ = SingletonFor(type, &state);
    162 }
    163 
    164 
    165 StackFrame* StackFrameIterator::SingletonFor(StackFrame::Type type,
    166                                              StackFrame::State* state) {
    167   if (type == StackFrame::NONE) return NULL;
    168   StackFrame* result = SingletonFor(type);
    169   ASSERT(result != NULL);
    170   result->state_ = *state;
    171   return result;
    172 }
    173 
    174 
    175 StackFrame* StackFrameIterator::SingletonFor(StackFrame::Type type) {
    176 #define FRAME_TYPE_CASE(type, field) \
    177   case StackFrame::type: result = &field##_; break;
    178 
    179   StackFrame* result = NULL;
    180   switch (type) {
    181     case StackFrame::NONE: return NULL;
    182     STACK_FRAME_TYPE_LIST(FRAME_TYPE_CASE)
    183     default: break;
    184   }
    185   return result;
    186 
    187 #undef FRAME_TYPE_CASE
    188 }
    189 
    190 
    191 // -------------------------------------------------------------------------
    192 
    193 
    194 StackTraceFrameIterator::StackTraceFrameIterator() {
    195   if (!done() && !IsValidFrame()) Advance();
    196 }
    197 
    198 
    199 StackTraceFrameIterator::StackTraceFrameIterator(Isolate* isolate)
    200     : JavaScriptFrameIterator(isolate) {
    201   if (!done() && !IsValidFrame()) Advance();
    202 }
    203 
    204 
    205 void StackTraceFrameIterator::Advance() {
    206   while (true) {
    207     JavaScriptFrameIterator::Advance();
    208     if (done()) return;
    209     if (IsValidFrame()) return;
    210   }
    211 }
    212 
    213 bool StackTraceFrameIterator::IsValidFrame() {
    214     if (!frame()->function()->IsJSFunction()) return false;
    215     Object* script = JSFunction::cast(frame()->function())->shared()->script();
    216     // Don't show functions from native scripts to user.
    217     return (script->IsScript() &&
    218             Script::TYPE_NATIVE != Script::cast(script)->type()->value());
    219 }
    220 
    221 
    222 // -------------------------------------------------------------------------
    223 
    224 
    225 bool SafeStackFrameIterator::ExitFrameValidator::IsValidFP(Address fp) {
    226   if (!validator_.IsValid(fp)) return false;
    227   Address sp = ExitFrame::ComputeStackPointer(fp);
    228   if (!validator_.IsValid(sp)) return false;
    229   StackFrame::State state;
    230   ExitFrame::FillState(fp, sp, &state);
    231   if (!validator_.IsValid(reinterpret_cast<Address>(state.pc_address))) {
    232     return false;
    233   }
    234   return *state.pc_address != NULL;
    235 }
    236 
    237 
    238 SafeStackFrameIterator::ActiveCountMaintainer::ActiveCountMaintainer(
    239     Isolate* isolate)
    240     : isolate_(isolate) {
    241   isolate_->set_safe_stack_iterator_counter(
    242       isolate_->safe_stack_iterator_counter() + 1);
    243 }
    244 
    245 
    246 SafeStackFrameIterator::ActiveCountMaintainer::~ActiveCountMaintainer() {
    247   isolate_->set_safe_stack_iterator_counter(
    248       isolate_->safe_stack_iterator_counter() - 1);
    249 }
    250 
    251 
    252 SafeStackFrameIterator::SafeStackFrameIterator(
    253     Isolate* isolate,
    254     Address fp, Address sp, Address low_bound, Address high_bound) :
    255     maintainer_(isolate),
    256     stack_validator_(low_bound, high_bound),
    257     is_valid_top_(IsValidTop(isolate, low_bound, high_bound)),
    258     is_valid_fp_(IsWithinBounds(low_bound, high_bound, fp)),
    259     is_working_iterator_(is_valid_top_ || is_valid_fp_),
    260     iteration_done_(!is_working_iterator_),
    261     iterator_(isolate, is_valid_top_, is_valid_fp_ ? fp : NULL, sp) {
    262 }
    263 
    264 bool SafeStackFrameIterator::is_active(Isolate* isolate) {
    265   return isolate->safe_stack_iterator_counter() > 0;
    266 }
    267 
    268 
    269 bool SafeStackFrameIterator::IsValidTop(Isolate* isolate,
    270                                         Address low_bound, Address high_bound) {
    271   ThreadLocalTop* top = isolate->thread_local_top();
    272   Address fp = Isolate::c_entry_fp(top);
    273   ExitFrameValidator validator(low_bound, high_bound);
    274   if (!validator.IsValidFP(fp)) return false;
    275   return Isolate::handler(top) != NULL;
    276 }
    277 
    278 
    279 void SafeStackFrameIterator::Advance() {
    280   ASSERT(is_working_iterator_);
    281   ASSERT(!done());
    282   StackFrame* last_frame = iterator_.frame();
    283   Address last_sp = last_frame->sp(), last_fp = last_frame->fp();
    284   // Before advancing to the next stack frame, perform pointer validity tests
    285   iteration_done_ = !IsValidFrame(last_frame) ||
    286       !CanIterateHandles(last_frame, iterator_.handler()) ||
    287       !IsValidCaller(last_frame);
    288   if (iteration_done_) return;
    289 
    290   iterator_.Advance();
    291   if (iterator_.done()) return;
    292   // Check that we have actually moved to the previous frame in the stack
    293   StackFrame* prev_frame = iterator_.frame();
    294   iteration_done_ = prev_frame->sp() < last_sp || prev_frame->fp() < last_fp;
    295 }
    296 
    297 
    298 bool SafeStackFrameIterator::CanIterateHandles(StackFrame* frame,
    299                                                StackHandler* handler) {
    300   // If StackIterator iterates over StackHandles, verify that
    301   // StackHandlerIterator can be instantiated (see StackHandlerIterator
    302   // constructor.)
    303   return !is_valid_top_ || (frame->sp() <= handler->address());
    304 }
    305 
    306 
    307 bool SafeStackFrameIterator::IsValidFrame(StackFrame* frame) const {
    308   return IsValidStackAddress(frame->sp()) && IsValidStackAddress(frame->fp());
    309 }
    310 
    311 
    312 bool SafeStackFrameIterator::IsValidCaller(StackFrame* frame) {
    313   StackFrame::State state;
    314   if (frame->is_entry() || frame->is_entry_construct()) {
    315     // See EntryFrame::GetCallerState. It computes the caller FP address
    316     // and calls ExitFrame::GetStateForFramePointer on it. We need to be
    317     // sure that caller FP address is valid.
    318     Address caller_fp = Memory::Address_at(
    319         frame->fp() + EntryFrameConstants::kCallerFPOffset);
    320     ExitFrameValidator validator(stack_validator_);
    321     if (!validator.IsValidFP(caller_fp)) return false;
    322   } else if (frame->is_arguments_adaptor()) {
    323     // See ArgumentsAdaptorFrame::GetCallerStackPointer. It assumes that
    324     // the number of arguments is stored on stack as Smi. We need to check
    325     // that it really an Smi.
    326     Object* number_of_args = reinterpret_cast<ArgumentsAdaptorFrame*>(frame)->
    327         GetExpression(0);
    328     if (!number_of_args->IsSmi()) {
    329       return false;
    330     }
    331   }
    332   frame->ComputeCallerState(&state);
    333   return IsValidStackAddress(state.sp) && IsValidStackAddress(state.fp) &&
    334       iterator_.SingletonFor(frame->GetCallerState(&state)) != NULL;
    335 }
    336 
    337 
    338 void SafeStackFrameIterator::Reset() {
    339   if (is_working_iterator_) {
    340     iterator_.Reset();
    341     iteration_done_ = false;
    342   }
    343 }
    344 
    345 
    346 // -------------------------------------------------------------------------
    347 
    348 
    349 #ifdef ENABLE_LOGGING_AND_PROFILING
    350 SafeStackTraceFrameIterator::SafeStackTraceFrameIterator(
    351     Isolate* isolate,
    352     Address fp, Address sp, Address low_bound, Address high_bound) :
    353     SafeJavaScriptFrameIterator(isolate, fp, sp, low_bound, high_bound) {
    354   if (!done() && !frame()->is_java_script()) Advance();
    355 }
    356 
    357 
    358 void SafeStackTraceFrameIterator::Advance() {
    359   while (true) {
    360     SafeJavaScriptFrameIterator::Advance();
    361     if (done()) return;
    362     if (frame()->is_java_script()) return;
    363   }
    364 }
    365 #endif
    366 
    367 
    368 Code* StackFrame::GetSafepointData(Isolate* isolate,
    369                                    Address pc,
    370                                    SafepointEntry* safepoint_entry,
    371                                    unsigned* stack_slots) {
    372   PcToCodeCache::PcToCodeCacheEntry* entry =
    373       isolate->pc_to_code_cache()->GetCacheEntry(pc);
    374   SafepointEntry cached_safepoint_entry = entry->safepoint_entry;
    375   if (!entry->safepoint_entry.is_valid()) {
    376     entry->safepoint_entry = entry->code->GetSafepointEntry(pc);
    377     ASSERT(entry->safepoint_entry.is_valid());
    378   } else {
    379     ASSERT(entry->safepoint_entry.Equals(entry->code->GetSafepointEntry(pc)));
    380   }
    381 
    382   // Fill in the results and return the code.
    383   Code* code = entry->code;
    384   *safepoint_entry = entry->safepoint_entry;
    385   *stack_slots = code->stack_slots();
    386   return code;
    387 }
    388 
    389 
    390 bool StackFrame::HasHandler() const {
    391   StackHandlerIterator it(this, top_handler());
    392   return !it.done();
    393 }
    394 
    395 
    396 void StackFrame::IteratePc(ObjectVisitor* v,
    397                            Address* pc_address,
    398                            Code* holder) {
    399   Address pc = *pc_address;
    400   ASSERT(holder->contains(pc));
    401   unsigned pc_offset = static_cast<unsigned>(pc - holder->instruction_start());
    402   Object* code = holder;
    403   v->VisitPointer(&code);
    404   if (code != holder) {
    405     holder = reinterpret_cast<Code*>(code);
    406     pc = holder->instruction_start() + pc_offset;
    407     *pc_address = pc;
    408   }
    409 }
    410 
    411 
    412 StackFrame::Type StackFrame::ComputeType(Isolate* isolate, State* state) {
    413   ASSERT(state->fp != NULL);
    414   if (StandardFrame::IsArgumentsAdaptorFrame(state->fp)) {
    415     return ARGUMENTS_ADAPTOR;
    416   }
    417   // The marker and function offsets overlap. If the marker isn't a
    418   // smi then the frame is a JavaScript frame -- and the marker is
    419   // really the function.
    420   const int offset = StandardFrameConstants::kMarkerOffset;
    421   Object* marker = Memory::Object_at(state->fp + offset);
    422   if (!marker->IsSmi()) {
    423     // If we're using a "safe" stack iterator, we treat optimized
    424     // frames as normal JavaScript frames to avoid having to look
    425     // into the heap to determine the state. This is safe as long
    426     // as nobody tries to GC...
    427     if (SafeStackFrameIterator::is_active(isolate)) return JAVA_SCRIPT;
    428     Code::Kind kind = GetContainingCode(isolate, *(state->pc_address))->kind();
    429     ASSERT(kind == Code::FUNCTION || kind == Code::OPTIMIZED_FUNCTION);
    430     return (kind == Code::OPTIMIZED_FUNCTION) ? OPTIMIZED : JAVA_SCRIPT;
    431   }
    432   return static_cast<StackFrame::Type>(Smi::cast(marker)->value());
    433 }
    434 
    435 
    436 
    437 StackFrame::Type StackFrame::GetCallerState(State* state) const {
    438   ComputeCallerState(state);
    439   return ComputeType(isolate(), state);
    440 }
    441 
    442 
    443 Code* EntryFrame::unchecked_code() const {
    444   return HEAP->raw_unchecked_js_entry_code();
    445 }
    446 
    447 
    448 void EntryFrame::ComputeCallerState(State* state) const {
    449   GetCallerState(state);
    450 }
    451 
    452 
    453 void EntryFrame::SetCallerFp(Address caller_fp) {
    454   const int offset = EntryFrameConstants::kCallerFPOffset;
    455   Memory::Address_at(this->fp() + offset) = caller_fp;
    456 }
    457 
    458 
    459 StackFrame::Type EntryFrame::GetCallerState(State* state) const {
    460   const int offset = EntryFrameConstants::kCallerFPOffset;
    461   Address fp = Memory::Address_at(this->fp() + offset);
    462   return ExitFrame::GetStateForFramePointer(fp, state);
    463 }
    464 
    465 
    466 Code* EntryConstructFrame::unchecked_code() const {
    467   return HEAP->raw_unchecked_js_construct_entry_code();
    468 }
    469 
    470 
    471 Object*& ExitFrame::code_slot() const {
    472   const int offset = ExitFrameConstants::kCodeOffset;
    473   return Memory::Object_at(fp() + offset);
    474 }
    475 
    476 
    477 Code* ExitFrame::unchecked_code() const {
    478   return reinterpret_cast<Code*>(code_slot());
    479 }
    480 
    481 
    482 void ExitFrame::ComputeCallerState(State* state) const {
    483   // Setup the caller state.
    484   state->sp = caller_sp();
    485   state->fp = Memory::Address_at(fp() + ExitFrameConstants::kCallerFPOffset);
    486   state->pc_address
    487       = reinterpret_cast<Address*>(fp() + ExitFrameConstants::kCallerPCOffset);
    488 }
    489 
    490 
    491 void ExitFrame::SetCallerFp(Address caller_fp) {
    492   Memory::Address_at(fp() + ExitFrameConstants::kCallerFPOffset) = caller_fp;
    493 }
    494 
    495 
    496 void ExitFrame::Iterate(ObjectVisitor* v) const {
    497   // The arguments are traversed as part of the expression stack of
    498   // the calling frame.
    499   IteratePc(v, pc_address(), LookupCode());
    500   v->VisitPointer(&code_slot());
    501 }
    502 
    503 
    504 Address ExitFrame::GetCallerStackPointer() const {
    505   return fp() + ExitFrameConstants::kCallerSPDisplacement;
    506 }
    507 
    508 
    509 StackFrame::Type ExitFrame::GetStateForFramePointer(Address fp, State* state) {
    510   if (fp == 0) return NONE;
    511   Address sp = ComputeStackPointer(fp);
    512   FillState(fp, sp, state);
    513   ASSERT(*state->pc_address != NULL);
    514   return EXIT;
    515 }
    516 
    517 
    518 void ExitFrame::FillState(Address fp, Address sp, State* state) {
    519   state->sp = sp;
    520   state->fp = fp;
    521   state->pc_address = reinterpret_cast<Address*>(sp - 1 * kPointerSize);
    522 }
    523 
    524 
    525 Address StandardFrame::GetExpressionAddress(int n) const {
    526   const int offset = StandardFrameConstants::kExpressionsOffset;
    527   return fp() + offset - n * kPointerSize;
    528 }
    529 
    530 
    531 int StandardFrame::ComputeExpressionsCount() const {
    532   const int offset =
    533       StandardFrameConstants::kExpressionsOffset + kPointerSize;
    534   Address base = fp() + offset;
    535   Address limit = sp();
    536   ASSERT(base >= limit);  // stack grows downwards
    537   // Include register-allocated locals in number of expressions.
    538   return static_cast<int>((base - limit) / kPointerSize);
    539 }
    540 
    541 
    542 void StandardFrame::ComputeCallerState(State* state) const {
    543   state->sp = caller_sp();
    544   state->fp = caller_fp();
    545   state->pc_address = reinterpret_cast<Address*>(ComputePCAddress(fp()));
    546 }
    547 
    548 
    549 void StandardFrame::SetCallerFp(Address caller_fp) {
    550   Memory::Address_at(fp() + StandardFrameConstants::kCallerFPOffset) =
    551       caller_fp;
    552 }
    553 
    554 
    555 bool StandardFrame::IsExpressionInsideHandler(int n) const {
    556   Address address = GetExpressionAddress(n);
    557   for (StackHandlerIterator it(this, top_handler()); !it.done(); it.Advance()) {
    558     if (it.handler()->includes(address)) return true;
    559   }
    560   return false;
    561 }
    562 
    563 
    564 void OptimizedFrame::Iterate(ObjectVisitor* v) const {
    565 #ifdef DEBUG
    566   // Make sure that optimized frames do not contain any stack handlers.
    567   StackHandlerIterator it(this, top_handler());
    568   ASSERT(it.done());
    569 #endif
    570 
    571   // Make sure that we're not doing "safe" stack frame iteration. We cannot
    572   // possibly find pointers in optimized frames in that state.
    573   ASSERT(!SafeStackFrameIterator::is_active(isolate()));
    574 
    575   // Compute the safepoint information.
    576   unsigned stack_slots = 0;
    577   SafepointEntry safepoint_entry;
    578   Code* code = StackFrame::GetSafepointData(
    579       isolate(), pc(), &safepoint_entry, &stack_slots);
    580   unsigned slot_space = stack_slots * kPointerSize;
    581 
    582   // Visit the outgoing parameters.
    583   Object** parameters_base = &Memory::Object_at(sp());
    584   Object** parameters_limit = &Memory::Object_at(
    585       fp() + JavaScriptFrameConstants::kFunctionOffset - slot_space);
    586 
    587   // Visit the parameters that may be on top of the saved registers.
    588   if (safepoint_entry.argument_count() > 0) {
    589     v->VisitPointers(parameters_base,
    590                      parameters_base + safepoint_entry.argument_count());
    591     parameters_base += safepoint_entry.argument_count();
    592   }
    593 
    594   // Skip saved double registers.
    595   if (safepoint_entry.has_doubles()) {
    596     parameters_base += DoubleRegister::kNumAllocatableRegisters *
    597         kDoubleSize / kPointerSize;
    598   }
    599 
    600   // Visit the registers that contain pointers if any.
    601   if (safepoint_entry.HasRegisters()) {
    602     for (int i = kNumSafepointRegisters - 1; i >=0; i--) {
    603       if (safepoint_entry.HasRegisterAt(i)) {
    604         int reg_stack_index = MacroAssembler::SafepointRegisterStackIndex(i);
    605         v->VisitPointer(parameters_base + reg_stack_index);
    606       }
    607     }
    608     // Skip the words containing the register values.
    609     parameters_base += kNumSafepointRegisters;
    610   }
    611 
    612   // We're done dealing with the register bits.
    613   uint8_t* safepoint_bits = safepoint_entry.bits();
    614   safepoint_bits += kNumSafepointRegisters >> kBitsPerByteLog2;
    615 
    616   // Visit the rest of the parameters.
    617   v->VisitPointers(parameters_base, parameters_limit);
    618 
    619   // Visit pointer spill slots and locals.
    620   for (unsigned index = 0; index < stack_slots; index++) {
    621     int byte_index = index >> kBitsPerByteLog2;
    622     int bit_index = index & (kBitsPerByte - 1);
    623     if ((safepoint_bits[byte_index] & (1U << bit_index)) != 0) {
    624       v->VisitPointer(parameters_limit + index);
    625     }
    626   }
    627 
    628   // Visit the context and the function.
    629   Object** fixed_base = &Memory::Object_at(
    630       fp() + JavaScriptFrameConstants::kFunctionOffset);
    631   Object** fixed_limit = &Memory::Object_at(fp());
    632   v->VisitPointers(fixed_base, fixed_limit);
    633 
    634   // Visit the return address in the callee and incoming arguments.
    635   IteratePc(v, pc_address(), code);
    636 }
    637 
    638 
    639 bool JavaScriptFrame::IsConstructor() const {
    640   Address fp = caller_fp();
    641   if (has_adapted_arguments()) {
    642     // Skip the arguments adaptor frame and look at the real caller.
    643     fp = Memory::Address_at(fp + StandardFrameConstants::kCallerFPOffset);
    644   }
    645   return IsConstructFrame(fp);
    646 }
    647 
    648 
    649 Code* JavaScriptFrame::unchecked_code() const {
    650   JSFunction* function = JSFunction::cast(this->function());
    651   return function->unchecked_code();
    652 }
    653 
    654 
    655 int JavaScriptFrame::GetNumberOfIncomingArguments() const {
    656   ASSERT(!SafeStackFrameIterator::is_active(isolate()) &&
    657          isolate()->heap()->gc_state() == Heap::NOT_IN_GC);
    658 
    659   JSFunction* function = JSFunction::cast(this->function());
    660   return function->shared()->formal_parameter_count();
    661 }
    662 
    663 
    664 Address JavaScriptFrame::GetCallerStackPointer() const {
    665   return fp() + StandardFrameConstants::kCallerSPOffset;
    666 }
    667 
    668 
    669 void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) {
    670   ASSERT(functions->length() == 0);
    671   functions->Add(JSFunction::cast(function()));
    672 }
    673 
    674 
    675 void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
    676   ASSERT(functions->length() == 0);
    677   Code* code_pointer = LookupCode();
    678   int offset = static_cast<int>(pc() - code_pointer->address());
    679   FrameSummary summary(receiver(),
    680                        JSFunction::cast(function()),
    681                        code_pointer,
    682                        offset,
    683                        IsConstructor());
    684   functions->Add(summary);
    685 }
    686 
    687 
    688 void FrameSummary::Print() {
    689   PrintF("receiver: ");
    690   receiver_->ShortPrint();
    691   PrintF("\nfunction: ");
    692   function_->shared()->DebugName()->ShortPrint();
    693   PrintF("\ncode: ");
    694   code_->ShortPrint();
    695   if (code_->kind() == Code::FUNCTION) PrintF(" NON-OPT");
    696   if (code_->kind() == Code::OPTIMIZED_FUNCTION) PrintF(" OPT");
    697   PrintF("\npc: %d\n", offset_);
    698 }
    699 
    700 
    701 void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
    702   ASSERT(frames->length() == 0);
    703   ASSERT(is_optimized());
    704 
    705   int deopt_index = Safepoint::kNoDeoptimizationIndex;
    706   DeoptimizationInputData* data = GetDeoptimizationData(&deopt_index);
    707 
    708   // BUG(3243555): Since we don't have a lazy-deopt registered at
    709   // throw-statements, we can't use the translation at the call-site of
    710   // throw. An entry with no deoptimization index indicates a call-site
    711   // without a lazy-deopt. As a consequence we are not allowed to inline
    712   // functions containing throw.
    713   if (deopt_index == Safepoint::kNoDeoptimizationIndex) {
    714     JavaScriptFrame::Summarize(frames);
    715     return;
    716   }
    717 
    718   TranslationIterator it(data->TranslationByteArray(),
    719                          data->TranslationIndex(deopt_index)->value());
    720   Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
    721   ASSERT(opcode == Translation::BEGIN);
    722   int frame_count = it.Next();
    723 
    724   // We create the summary in reverse order because the frames
    725   // in the deoptimization translation are ordered bottom-to-top.
    726   int i = frame_count;
    727   while (i > 0) {
    728     opcode = static_cast<Translation::Opcode>(it.Next());
    729     if (opcode == Translation::FRAME) {
    730       // We don't inline constructor calls, so only the first, outermost
    731       // frame can be a constructor frame in case of inlining.
    732       bool is_constructor = (i == frame_count) && IsConstructor();
    733 
    734       i--;
    735       int ast_id = it.Next();
    736       int function_id = it.Next();
    737       it.Next();  // Skip height.
    738       JSFunction* function =
    739           JSFunction::cast(data->LiteralArray()->get(function_id));
    740 
    741       // The translation commands are ordered and the receiver is always
    742       // at the first position. Since we are always at a call when we need
    743       // to construct a stack trace, the receiver is always in a stack slot.
    744       opcode = static_cast<Translation::Opcode>(it.Next());
    745       ASSERT(opcode == Translation::STACK_SLOT);
    746       int input_slot_index = it.Next();
    747 
    748       // Get the correct receiver in the optimized frame.
    749       Object* receiver = NULL;
    750       // Positive index means the value is spilled to the locals area. Negative
    751       // means it is stored in the incoming parameter area.
    752       if (input_slot_index >= 0) {
    753         receiver = GetExpression(input_slot_index);
    754       } else {
    755         // Index -1 overlaps with last parameter, -n with the first parameter,
    756         // (-n - 1) with the receiver with n being the number of parameters
    757         // of the outermost, optimized frame.
    758         int parameter_count = ComputeParametersCount();
    759         int parameter_index = input_slot_index + parameter_count;
    760         receiver = (parameter_index == -1)
    761             ? this->receiver()
    762             : this->GetParameter(parameter_index);
    763       }
    764 
    765       Code* code = function->shared()->code();
    766       DeoptimizationOutputData* output_data =
    767           DeoptimizationOutputData::cast(code->deoptimization_data());
    768       unsigned entry = Deoptimizer::GetOutputInfo(output_data,
    769                                                   ast_id,
    770                                                   function->shared());
    771       unsigned pc_offset =
    772           FullCodeGenerator::PcField::decode(entry) + Code::kHeaderSize;
    773       ASSERT(pc_offset > 0);
    774 
    775       FrameSummary summary(receiver, function, code, pc_offset, is_constructor);
    776       frames->Add(summary);
    777     } else {
    778       // Skip over operands to advance to the next opcode.
    779       it.Skip(Translation::NumberOfOperandsFor(opcode));
    780     }
    781   }
    782 }
    783 
    784 
    785 DeoptimizationInputData* OptimizedFrame::GetDeoptimizationData(
    786     int* deopt_index) {
    787   ASSERT(is_optimized());
    788 
    789   JSFunction* opt_function = JSFunction::cast(function());
    790   Code* code = opt_function->code();
    791 
    792   // The code object may have been replaced by lazy deoptimization. Fall
    793   // back to a slow search in this case to find the original optimized
    794   // code object.
    795   if (!code->contains(pc())) {
    796     code = isolate()->pc_to_code_cache()->GcSafeFindCodeForPc(pc());
    797   }
    798   ASSERT(code != NULL);
    799   ASSERT(code->kind() == Code::OPTIMIZED_FUNCTION);
    800 
    801   SafepointEntry safepoint_entry = code->GetSafepointEntry(pc());
    802   *deopt_index = safepoint_entry.deoptimization_index();
    803   ASSERT(*deopt_index != Safepoint::kNoDeoptimizationIndex);
    804 
    805   return DeoptimizationInputData::cast(code->deoptimization_data());
    806 }
    807 
    808 
    809 void OptimizedFrame::GetFunctions(List<JSFunction*>* functions) {
    810   ASSERT(functions->length() == 0);
    811   ASSERT(is_optimized());
    812 
    813   int deopt_index = Safepoint::kNoDeoptimizationIndex;
    814   DeoptimizationInputData* data = GetDeoptimizationData(&deopt_index);
    815 
    816   TranslationIterator it(data->TranslationByteArray(),
    817                          data->TranslationIndex(deopt_index)->value());
    818   Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
    819   ASSERT(opcode == Translation::BEGIN);
    820   int frame_count = it.Next();
    821 
    822   // We insert the frames in reverse order because the frames
    823   // in the deoptimization translation are ordered bottom-to-top.
    824   while (frame_count > 0) {
    825     opcode = static_cast<Translation::Opcode>(it.Next());
    826     if (opcode == Translation::FRAME) {
    827       frame_count--;
    828       it.Next();  // Skip ast id.
    829       int function_id = it.Next();
    830       it.Next();  // Skip height.
    831       JSFunction* function =
    832           JSFunction::cast(data->LiteralArray()->get(function_id));
    833       functions->Add(function);
    834     } else {
    835       // Skip over operands to advance to the next opcode.
    836       it.Skip(Translation::NumberOfOperandsFor(opcode));
    837     }
    838   }
    839 }
    840 
    841 
    842 Address ArgumentsAdaptorFrame::GetCallerStackPointer() const {
    843   return fp() + StandardFrameConstants::kCallerSPOffset;
    844 }
    845 
    846 
    847 Address InternalFrame::GetCallerStackPointer() const {
    848   // Internal frames have no arguments. The stack pointer of the
    849   // caller is at a fixed offset from the frame pointer.
    850   return fp() + StandardFrameConstants::kCallerSPOffset;
    851 }
    852 
    853 
    854 Code* ArgumentsAdaptorFrame::unchecked_code() const {
    855   return isolate()->builtins()->builtin(
    856       Builtins::kArgumentsAdaptorTrampoline);
    857 }
    858 
    859 
    860 Code* InternalFrame::unchecked_code() const {
    861   const int offset = InternalFrameConstants::kCodeOffset;
    862   Object* code = Memory::Object_at(fp() + offset);
    863   ASSERT(code != NULL);
    864   return reinterpret_cast<Code*>(code);
    865 }
    866 
    867 
    868 void StackFrame::PrintIndex(StringStream* accumulator,
    869                             PrintMode mode,
    870                             int index) {
    871   accumulator->Add((mode == OVERVIEW) ? "%5d: " : "[%d]: ", index);
    872 }
    873 
    874 
    875 void JavaScriptFrame::Print(StringStream* accumulator,
    876                             PrintMode mode,
    877                             int index) const {
    878   HandleScope scope;
    879   Object* receiver = this->receiver();
    880   Object* function = this->function();
    881 
    882   accumulator->PrintSecurityTokenIfChanged(function);
    883   PrintIndex(accumulator, mode, index);
    884   Code* code = NULL;
    885   if (IsConstructor()) accumulator->Add("new ");
    886   accumulator->PrintFunction(function, receiver, &code);
    887 
    888   Handle<SerializedScopeInfo> scope_info(SerializedScopeInfo::Empty());
    889 
    890   if (function->IsJSFunction()) {
    891     Handle<SharedFunctionInfo> shared(JSFunction::cast(function)->shared());
    892     scope_info = Handle<SerializedScopeInfo>(shared->scope_info());
    893     Object* script_obj = shared->script();
    894     if (script_obj->IsScript()) {
    895       Handle<Script> script(Script::cast(script_obj));
    896       accumulator->Add(" [");
    897       accumulator->PrintName(script->name());
    898 
    899       Address pc = this->pc();
    900       if (code != NULL && code->kind() == Code::FUNCTION &&
    901           pc >= code->instruction_start() && pc < code->instruction_end()) {
    902         int source_pos = code->SourcePosition(pc);
    903         int line = GetScriptLineNumberSafe(script, source_pos) + 1;
    904         accumulator->Add(":%d", line);
    905       } else {
    906         int function_start_pos = shared->start_position();
    907         int line = GetScriptLineNumberSafe(script, function_start_pos) + 1;
    908         accumulator->Add(":~%d", line);
    909       }
    910 
    911       accumulator->Add("] ");
    912     }
    913   }
    914 
    915   accumulator->Add("(this=%o", receiver);
    916 
    917   // Get scope information for nicer output, if possible. If code is
    918   // NULL, or doesn't contain scope info, info will return 0 for the
    919   // number of parameters, stack slots, or context slots.
    920   ScopeInfo<PreallocatedStorage> info(*scope_info);
    921 
    922   // Print the parameters.
    923   int parameters_count = ComputeParametersCount();
    924   for (int i = 0; i < parameters_count; i++) {
    925     accumulator->Add(",");
    926     // If we have a name for the parameter we print it. Nameless
    927     // parameters are either because we have more actual parameters
    928     // than formal parameters or because we have no scope information.
    929     if (i < info.number_of_parameters()) {
    930       accumulator->PrintName(*info.parameter_name(i));
    931       accumulator->Add("=");
    932     }
    933     accumulator->Add("%o", GetParameter(i));
    934   }
    935 
    936   accumulator->Add(")");
    937   if (mode == OVERVIEW) {
    938     accumulator->Add("\n");
    939     return;
    940   }
    941   accumulator->Add(" {\n");
    942 
    943   // Compute the number of locals and expression stack elements.
    944   int stack_locals_count = info.number_of_stack_slots();
    945   int heap_locals_count = info.number_of_context_slots();
    946   int expressions_count = ComputeExpressionsCount();
    947 
    948   // Print stack-allocated local variables.
    949   if (stack_locals_count > 0) {
    950     accumulator->Add("  // stack-allocated locals\n");
    951   }
    952   for (int i = 0; i < stack_locals_count; i++) {
    953     accumulator->Add("  var ");
    954     accumulator->PrintName(*info.stack_slot_name(i));
    955     accumulator->Add(" = ");
    956     if (i < expressions_count) {
    957       accumulator->Add("%o", GetExpression(i));
    958     } else {
    959       accumulator->Add("// no expression found - inconsistent frame?");
    960     }
    961     accumulator->Add("\n");
    962   }
    963 
    964   // Try to get hold of the context of this frame.
    965   Context* context = NULL;
    966   if (this->context() != NULL && this->context()->IsContext()) {
    967     context = Context::cast(this->context());
    968   }
    969 
    970   // Print heap-allocated local variables.
    971   if (heap_locals_count > Context::MIN_CONTEXT_SLOTS) {
    972     accumulator->Add("  // heap-allocated locals\n");
    973   }
    974   for (int i = Context::MIN_CONTEXT_SLOTS; i < heap_locals_count; i++) {
    975     accumulator->Add("  var ");
    976     accumulator->PrintName(*info.context_slot_name(i));
    977     accumulator->Add(" = ");
    978     if (context != NULL) {
    979       if (i < context->length()) {
    980         accumulator->Add("%o", context->get(i));
    981       } else {
    982         accumulator->Add(
    983             "// warning: missing context slot - inconsistent frame?");
    984       }
    985     } else {
    986       accumulator->Add("// warning: no context found - inconsistent frame?");
    987     }
    988     accumulator->Add("\n");
    989   }
    990 
    991   // Print the expression stack.
    992   int expressions_start = stack_locals_count;
    993   if (expressions_start < expressions_count) {
    994     accumulator->Add("  // expression stack (top to bottom)\n");
    995   }
    996   for (int i = expressions_count - 1; i >= expressions_start; i--) {
    997     if (IsExpressionInsideHandler(i)) continue;
    998     accumulator->Add("  [%02d] : %o\n", i, GetExpression(i));
    999   }
   1000 
   1001   // Print details about the function.
   1002   if (FLAG_max_stack_trace_source_length != 0 && code != NULL) {
   1003     SharedFunctionInfo* shared = JSFunction::cast(function)->shared();
   1004     accumulator->Add("--------- s o u r c e   c o d e ---------\n");
   1005     shared->SourceCodePrint(accumulator, FLAG_max_stack_trace_source_length);
   1006     accumulator->Add("\n-----------------------------------------\n");
   1007   }
   1008 
   1009   accumulator->Add("}\n\n");
   1010 }
   1011 
   1012 
   1013 void ArgumentsAdaptorFrame::Print(StringStream* accumulator,
   1014                                   PrintMode mode,
   1015                                   int index) const {
   1016   int actual = ComputeParametersCount();
   1017   int expected = -1;
   1018   Object* function = this->function();
   1019   if (function->IsJSFunction()) {
   1020     expected = JSFunction::cast(function)->shared()->formal_parameter_count();
   1021   }
   1022 
   1023   PrintIndex(accumulator, mode, index);
   1024   accumulator->Add("arguments adaptor frame: %d->%d", actual, expected);
   1025   if (mode == OVERVIEW) {
   1026     accumulator->Add("\n");
   1027     return;
   1028   }
   1029   accumulator->Add(" {\n");
   1030 
   1031   // Print actual arguments.
   1032   if (actual > 0) accumulator->Add("  // actual arguments\n");
   1033   for (int i = 0; i < actual; i++) {
   1034     accumulator->Add("  [%02d] : %o", i, GetParameter(i));
   1035     if (expected != -1 && i >= expected) {
   1036       accumulator->Add("  // not passed to callee");
   1037     }
   1038     accumulator->Add("\n");
   1039   }
   1040 
   1041   accumulator->Add("}\n\n");
   1042 }
   1043 
   1044 
   1045 void EntryFrame::Iterate(ObjectVisitor* v) const {
   1046   StackHandlerIterator it(this, top_handler());
   1047   ASSERT(!it.done());
   1048   StackHandler* handler = it.handler();
   1049   ASSERT(handler->is_entry());
   1050   handler->Iterate(v, LookupCode());
   1051 #ifdef DEBUG
   1052   // Make sure that the entry frame does not contain more than one
   1053   // stack handler.
   1054   it.Advance();
   1055   ASSERT(it.done());
   1056 #endif
   1057   IteratePc(v, pc_address(), LookupCode());
   1058 }
   1059 
   1060 
   1061 void StandardFrame::IterateExpressions(ObjectVisitor* v) const {
   1062   const int offset = StandardFrameConstants::kContextOffset;
   1063   Object** base = &Memory::Object_at(sp());
   1064   Object** limit = &Memory::Object_at(fp() + offset) + 1;
   1065   for (StackHandlerIterator it(this, top_handler()); !it.done(); it.Advance()) {
   1066     StackHandler* handler = it.handler();
   1067     // Traverse pointers down to - but not including - the next
   1068     // handler in the handler chain. Update the base to skip the
   1069     // handler and allow the handler to traverse its own pointers.
   1070     const Address address = handler->address();
   1071     v->VisitPointers(base, reinterpret_cast<Object**>(address));
   1072     base = reinterpret_cast<Object**>(address + StackHandlerConstants::kSize);
   1073     // Traverse the pointers in the handler itself.
   1074     handler->Iterate(v, LookupCode());
   1075   }
   1076   v->VisitPointers(base, limit);
   1077 }
   1078 
   1079 
   1080 void JavaScriptFrame::Iterate(ObjectVisitor* v) const {
   1081   IterateExpressions(v);
   1082   IteratePc(v, pc_address(), LookupCode());
   1083 }
   1084 
   1085 
   1086 void InternalFrame::Iterate(ObjectVisitor* v) const {
   1087   // Internal frames only have object pointers on the expression stack
   1088   // as they never have any arguments.
   1089   IterateExpressions(v);
   1090   IteratePc(v, pc_address(), LookupCode());
   1091 }
   1092 
   1093 
   1094 // -------------------------------------------------------------------------
   1095 
   1096 
   1097 JavaScriptFrame* StackFrameLocator::FindJavaScriptFrame(int n) {
   1098   ASSERT(n >= 0);
   1099   for (int i = 0; i <= n; i++) {
   1100     while (!iterator_.frame()->is_java_script()) iterator_.Advance();
   1101     if (i == n) return JavaScriptFrame::cast(iterator_.frame());
   1102     iterator_.Advance();
   1103   }
   1104   UNREACHABLE();
   1105   return NULL;
   1106 }
   1107 
   1108 
   1109 // -------------------------------------------------------------------------
   1110 
   1111 
   1112 Code* PcToCodeCache::GcSafeCastToCode(HeapObject* object, Address pc) {
   1113   Code* code = reinterpret_cast<Code*>(object);
   1114   ASSERT(code != NULL && code->contains(pc));
   1115   return code;
   1116 }
   1117 
   1118 
   1119 Code* PcToCodeCache::GcSafeFindCodeForPc(Address pc) {
   1120   Heap* heap = isolate_->heap();
   1121   // Check if the pc points into a large object chunk.
   1122   LargeObjectChunk* chunk = heap->lo_space()->FindChunkContainingPc(pc);
   1123   if (chunk != NULL) return GcSafeCastToCode(chunk->GetObject(), pc);
   1124 
   1125   // Iterate through the 8K page until we reach the end or find an
   1126   // object starting after the pc.
   1127   Page* page = Page::FromAddress(pc);
   1128   HeapObjectIterator iterator(page, heap->GcSafeSizeOfOldObjectFunction());
   1129   HeapObject* previous = NULL;
   1130   while (true) {
   1131     HeapObject* next = iterator.next();
   1132     if (next == NULL || next->address() >= pc) {
   1133       return GcSafeCastToCode(previous, pc);
   1134     }
   1135     previous = next;
   1136   }
   1137 }
   1138 
   1139 
   1140 PcToCodeCache::PcToCodeCacheEntry* PcToCodeCache::GetCacheEntry(Address pc) {
   1141   isolate_->counters()->pc_to_code()->Increment();
   1142   ASSERT(IsPowerOf2(kPcToCodeCacheSize));
   1143   uint32_t hash = ComputeIntegerHash(
   1144       static_cast<uint32_t>(reinterpret_cast<uintptr_t>(pc)));
   1145   uint32_t index = hash & (kPcToCodeCacheSize - 1);
   1146   PcToCodeCacheEntry* entry = cache(index);
   1147   if (entry->pc == pc) {
   1148     isolate_->counters()->pc_to_code_cached()->Increment();
   1149     ASSERT(entry->code == GcSafeFindCodeForPc(pc));
   1150   } else {
   1151     // Because this code may be interrupted by a profiling signal that
   1152     // also queries the cache, we cannot update pc before the code has
   1153     // been set. Otherwise, we risk trying to use a cache entry before
   1154     // the code has been computed.
   1155     entry->code = GcSafeFindCodeForPc(pc);
   1156     entry->safepoint_entry.Reset();
   1157     entry->pc = pc;
   1158   }
   1159   return entry;
   1160 }
   1161 
   1162 
   1163 // -------------------------------------------------------------------------
   1164 
   1165 int NumRegs(RegList reglist) {
   1166   int n = 0;
   1167   while (reglist != 0) {
   1168     n++;
   1169     reglist &= reglist - 1;  // clear one bit
   1170   }
   1171   return n;
   1172 }
   1173 
   1174 
   1175 struct JSCallerSavedCodeData {
   1176   JSCallerSavedCodeData() {
   1177     int i = 0;
   1178     for (int r = 0; r < kNumRegs; r++)
   1179       if ((kJSCallerSaved & (1 << r)) != 0)
   1180         reg_code[i++] = r;
   1181 
   1182     ASSERT(i == kNumJSCallerSaved);
   1183   }
   1184   int reg_code[kNumJSCallerSaved];
   1185 };
   1186 
   1187 
   1188 static const JSCallerSavedCodeData kCallerSavedCodeData;
   1189 
   1190 
   1191 int JSCallerSavedCode(int n) {
   1192   ASSERT(0 <= n && n < kNumJSCallerSaved);
   1193   return kCallerSavedCodeData.reg_code[n];
   1194 }
   1195 
   1196 
   1197 #define DEFINE_WRAPPER(type, field)                              \
   1198 class field##_Wrapper : public ZoneObject {                      \
   1199  public:  /* NOLINT */                                           \
   1200   field##_Wrapper(const field& original) : frame_(original) {    \
   1201   }                                                              \
   1202   field frame_;                                                  \
   1203 };
   1204 STACK_FRAME_TYPE_LIST(DEFINE_WRAPPER)
   1205 #undef DEFINE_WRAPPER
   1206 
   1207 static StackFrame* AllocateFrameCopy(StackFrame* frame) {
   1208 #define FRAME_TYPE_CASE(type, field) \
   1209   case StackFrame::type: { \
   1210     field##_Wrapper* wrapper = \
   1211         new field##_Wrapper(*(reinterpret_cast<field*>(frame))); \
   1212     return &wrapper->frame_; \
   1213   }
   1214 
   1215   switch (frame->type()) {
   1216     STACK_FRAME_TYPE_LIST(FRAME_TYPE_CASE)
   1217     default: UNREACHABLE();
   1218   }
   1219 #undef FRAME_TYPE_CASE
   1220   return NULL;
   1221 }
   1222 
   1223 Vector<StackFrame*> CreateStackMap() {
   1224   ZoneList<StackFrame*> list(10);
   1225   for (StackFrameIterator it; !it.done(); it.Advance()) {
   1226     StackFrame* frame = AllocateFrameCopy(it.frame());
   1227     list.Add(frame);
   1228   }
   1229   return list.ToVector();
   1230 }
   1231 
   1232 
   1233 } }  // namespace v8::internal
   1234