root/src/frames.cc

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DEFINITIONS

This source file includes following definitions.
  1. ResolveReturnAddressLocation
  2. handler_
  3. handler
  4. done
  5. Advance
  6. advance_
  7. advance_
  8. advance_
  9. advance_
  10. AdvanceWithHandler
  11. AdvanceWithoutHandler
  12. Reset
  13. SingletonFor
  14. SingletonFor
  15. Advance
  16. IsValidFrame
  17. IsValidFP
  18. iterator_
  19. is_active
  20. IsValidTop
  21. Advance
  22. CanIterateHandles
  23. IsValidFrame
  24. IsValidCaller
  25. Reset
  26. Advance
  27. GetSafepointData
  28. HasHandler
  29. IteratePc
  30. SetReturnAddressLocationResolver
  31. ComputeType
  32. GetCallerState
  33. UnpaddedFP
  34. unchecked_code
  35. ComputeCallerState
  36. SetCallerFp
  37. GetCallerState
  38. unchecked_code
  39. code_slot
  40. unchecked_code
  41. ComputeCallerState
  42. SetCallerFp
  43. Iterate
  44. GetCallerStackPointer
  45. GetStateForFramePointer
  46. FillState
  47. GetExpressionAddress
  48. GetExpression
  49. GetExpressionAddress
  50. ComputeExpressionsCount
  51. ComputeCallerState
  52. SetCallerFp
  53. IsExpressionInsideHandler
  54. Iterate
  55. IsConstructor
  56. GetArgumentsLength
  57. unchecked_code
  58. GetNumberOfIncomingArguments
  59. GetCallerStackPointer
  60. GetFunctions
  61. Summarize
  62. PrintTop
  63. Print
  64. LiteralAt
  65. Summarize
  66. GetDeoptimizationData
  67. GetInlineCount
  68. GetFunctions
  69. GetNumberOfIncomingArguments
  70. GetCallerStackPointer
  71. GetCallerStackPointer
  72. unchecked_code
  73. unchecked_code
  74. PrintIndex
  75. Print
  76. Print
  77. Iterate
  78. IterateExpressions
  79. Iterate
  80. Iterate
  81. FindJavaScriptFrame
  82. GcSafeMapOfCodeSpaceObject
  83. GcSafeSizeOfCodeSpaceObject
  84. GcSafeCodeContains
  85. GcSafeCastToCode
  86. GcSafeFindCodeForInnerPointer
  87. GetCacheEntry
  88. NumRegs
  89. SetUpJSCallerSavedCodeData
  90. JSCallerSavedCode
  91. STACK_FRAME_TYPE_LIST
  92. CreateStackMap

// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#include "ast.h"
#include "deoptimizer.h"
#include "frames-inl.h"
#include "full-codegen.h"
#include "lazy-instance.h"
#include "mark-compact.h"
#include "safepoint-table.h"
#include "scopeinfo.h"
#include "string-stream.h"

#include "allocation-inl.h"

namespace v8 {
namespace internal {


static ReturnAddressLocationResolver return_address_location_resolver = NULL;


// Resolves pc_address through the resolution address function if one is set.
static inline Address* ResolveReturnAddressLocation(Address* pc_address) {
  if (return_address_location_resolver == NULL) {
    return pc_address;
  } else {
    return reinterpret_cast<Address*>(
        return_address_location_resolver(
            reinterpret_cast<uintptr_t>(pc_address)));
  }
}


// Iterator that supports traversing the stack handlers of a
// particular frame. Needs to know the top of the handler chain.
class StackHandlerIterator BASE_EMBEDDED {
 public:
  StackHandlerIterator(const StackFrame* frame, StackHandler* handler)
      : limit_(frame->fp()), handler_(handler) {
    // Make sure the handler has already been unwound to this frame.
    ASSERT(frame->sp() <= handler->address());
  }

  StackHandler* handler() const { return handler_; }

  bool done() {
    return handler_ == NULL || handler_->address() > limit_;
  }
  void Advance() {
    ASSERT(!done());
    handler_ = handler_->next();
  }

 private:
  const Address limit_;
  StackHandler* handler_;
};


// -------------------------------------------------------------------------


#define INITIALIZE_SINGLETON(type, field) field##_(this),
StackFrameIterator::StackFrameIterator()
    : isolate_(Isolate::Current()),
      STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
      frame_(NULL), handler_(NULL),
      thread_(isolate_->thread_local_top()),
      fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
  Reset();
}
StackFrameIterator::StackFrameIterator(Isolate* isolate)
    : isolate_(isolate),
      STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
      frame_(NULL), handler_(NULL),
      thread_(isolate_->thread_local_top()),
      fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
  Reset();
}
StackFrameIterator::StackFrameIterator(Isolate* isolate, ThreadLocalTop* t)
    : isolate_(isolate),
      STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
      frame_(NULL), handler_(NULL), thread_(t),
      fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
  Reset();
}
StackFrameIterator::StackFrameIterator(Isolate* isolate,
                                       bool use_top, Address fp, Address sp)
    : isolate_(isolate),
      STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
      frame_(NULL), handler_(NULL),
      thread_(use_top ? isolate_->thread_local_top() : NULL),
      fp_(use_top ? NULL : fp), sp_(sp),
      advance_(use_top ? &StackFrameIterator::AdvanceWithHandler :
               &StackFrameIterator::AdvanceWithoutHandler) {
  if (use_top || fp != NULL) {
    Reset();
  }
}

#undef INITIALIZE_SINGLETON


void StackFrameIterator::AdvanceWithHandler() {
  ASSERT(!done());
  // Compute the state of the calling frame before restoring
  // callee-saved registers and unwinding handlers. This allows the
  // frame code that computes the caller state to access the top
  // handler and the value of any callee-saved register if needed.
  StackFrame::State state;
  StackFrame::Type type = frame_->GetCallerState(&state);

  // Unwind handlers corresponding to the current frame.
  StackHandlerIterator it(frame_, handler_);
  while (!it.done()) it.Advance();
  handler_ = it.handler();

  // Advance to the calling frame.
  frame_ = SingletonFor(type, &state);

  // When we're done iterating over the stack frames, the handler
  // chain must have been completely unwound.
  ASSERT(!done() || handler_ == NULL);
}


void StackFrameIterator::AdvanceWithoutHandler() {
  // A simpler version of Advance which doesn't care about handler.
  ASSERT(!done());
  StackFrame::State state;
  StackFrame::Type type = frame_->GetCallerState(&state);
  frame_ = SingletonFor(type, &state);
}


void StackFrameIterator::Reset() {
  StackFrame::State state;
  StackFrame::Type type;
  if (thread_ != NULL) {
    type = ExitFrame::GetStateForFramePointer(
        Isolate::c_entry_fp(thread_), &state);
    handler_ = StackHandler::FromAddress(
        Isolate::handler(thread_));
  } else {
    ASSERT(fp_ != NULL);
    state.fp = fp_;
    state.sp = sp_;
    state.pc_address = ResolveReturnAddressLocation(
        reinterpret_cast<Address*>(StandardFrame::ComputePCAddress(fp_)));
    type = StackFrame::ComputeType(isolate(), &state);
  }
  if (SingletonFor(type) == NULL) return;
  frame_ = SingletonFor(type, &state);
}


StackFrame* StackFrameIterator::SingletonFor(StackFrame::Type type,
                                             StackFrame::State* state) {
  if (type == StackFrame::NONE) return NULL;
  StackFrame* result = SingletonFor(type);
  ASSERT(result != NULL);
  result->state_ = *state;
  return result;
}


StackFrame* StackFrameIterator::SingletonFor(StackFrame::Type type) {
#define FRAME_TYPE_CASE(type, field) \
  case StackFrame::type: result = &field##_; break;

  StackFrame* result = NULL;
  switch (type) {
    case StackFrame::NONE: return NULL;
    STACK_FRAME_TYPE_LIST(FRAME_TYPE_CASE)
    default: break;
  }
  return result;

#undef FRAME_TYPE_CASE
}


// -------------------------------------------------------------------------


StackTraceFrameIterator::StackTraceFrameIterator() {
  if (!done() && !IsValidFrame()) Advance();
}


StackTraceFrameIterator::StackTraceFrameIterator(Isolate* isolate)
    : JavaScriptFrameIterator(isolate) {
  if (!done() && !IsValidFrame()) Advance();
}


void StackTraceFrameIterator::Advance() {
  while (true) {
    JavaScriptFrameIterator::Advance();
    if (done()) return;
    if (IsValidFrame()) return;
  }
}

bool StackTraceFrameIterator::IsValidFrame() {
    if (!frame()->function()->IsJSFunction()) return false;
    Object* script = JSFunction::cast(frame()->function())->shared()->script();
    // Don't show functions from native scripts to user.
    return (script->IsScript() &&
            Script::TYPE_NATIVE != Script::cast(script)->type()->value());
}


// -------------------------------------------------------------------------


bool SafeStackFrameIterator::ExitFrameValidator::IsValidFP(Address fp) {
  if (!validator_.IsValid(fp)) return false;
  Address sp = ExitFrame::ComputeStackPointer(fp);
  if (!validator_.IsValid(sp)) return false;
  StackFrame::State state;
  ExitFrame::FillState(fp, sp, &state);
  if (!validator_.IsValid(reinterpret_cast<Address>(state.pc_address))) {
    return false;
  }
  return *state.pc_address != NULL;
}


SafeStackFrameIterator::ActiveCountMaintainer::ActiveCountMaintainer(
    Isolate* isolate)
    : isolate_(isolate) {
  isolate_->set_safe_stack_iterator_counter(
      isolate_->safe_stack_iterator_counter() + 1);
}


SafeStackFrameIterator::ActiveCountMaintainer::~ActiveCountMaintainer() {
  isolate_->set_safe_stack_iterator_counter(
      isolate_->safe_stack_iterator_counter() - 1);
}


SafeStackFrameIterator::SafeStackFrameIterator(
    Isolate* isolate,
    Address fp, Address sp, Address low_bound, Address high_bound) :
    maintainer_(isolate),
    stack_validator_(low_bound, high_bound),
    is_valid_top_(IsValidTop(isolate, low_bound, high_bound)),
    is_valid_fp_(IsWithinBounds(low_bound, high_bound, fp)),
    is_working_iterator_(is_valid_top_ || is_valid_fp_),
    iteration_done_(!is_working_iterator_),
    iterator_(isolate, is_valid_top_, is_valid_fp_ ? fp : NULL, sp) {
}

bool SafeStackFrameIterator::is_active(Isolate* isolate) {
  return isolate->safe_stack_iterator_counter() > 0;
}


bool SafeStackFrameIterator::IsValidTop(Isolate* isolate,
                                        Address low_bound, Address high_bound) {
  ThreadLocalTop* top = isolate->thread_local_top();
  Address fp = Isolate::c_entry_fp(top);
  ExitFrameValidator validator(low_bound, high_bound);
  if (!validator.IsValidFP(fp)) return false;
  return Isolate::handler(top) != NULL;
}


void SafeStackFrameIterator::Advance() {
  ASSERT(is_working_iterator_);
  ASSERT(!done());
  StackFrame* last_frame = iterator_.frame();
  Address last_sp = last_frame->sp(), last_fp = last_frame->fp();
  // Before advancing to the next stack frame, perform pointer validity tests
  iteration_done_ = !IsValidFrame(last_frame) ||
      !CanIterateHandles(last_frame, iterator_.handler()) ||
      !IsValidCaller(last_frame);
  if (iteration_done_) return;

  iterator_.Advance();
  if (iterator_.done()) return;
  // Check that we have actually moved to the previous frame in the stack
  StackFrame* prev_frame = iterator_.frame();
  iteration_done_ = prev_frame->sp() < last_sp || prev_frame->fp() < last_fp;
}


bool SafeStackFrameIterator::CanIterateHandles(StackFrame* frame,
                                               StackHandler* handler) {
  // If StackIterator iterates over StackHandles, verify that
  // StackHandlerIterator can be instantiated (see StackHandlerIterator
  // constructor.)
  return !is_valid_top_ || (frame->sp() <= handler->address());
}


bool SafeStackFrameIterator::IsValidFrame(StackFrame* frame) const {
  return IsValidStackAddress(frame->sp()) && IsValidStackAddress(frame->fp());
}


bool SafeStackFrameIterator::IsValidCaller(StackFrame* frame) {
  StackFrame::State state;
  if (frame->is_entry() || frame->is_entry_construct()) {
    // See EntryFrame::GetCallerState. It computes the caller FP address
    // and calls ExitFrame::GetStateForFramePointer on it. We need to be
    // sure that caller FP address is valid.
    Address caller_fp = Memory::Address_at(
        frame->fp() + EntryFrameConstants::kCallerFPOffset);
    ExitFrameValidator validator(stack_validator_);
    if (!validator.IsValidFP(caller_fp)) return false;
  } else if (frame->is_arguments_adaptor()) {
    // See ArgumentsAdaptorFrame::GetCallerStackPointer. It assumes that
    // the number of arguments is stored on stack as Smi. We need to check
    // that it really an Smi.
    Object* number_of_args = reinterpret_cast<ArgumentsAdaptorFrame*>(frame)->
        GetExpression(0);
    if (!number_of_args->IsSmi()) {
      return false;
    }
  }
  frame->ComputeCallerState(&state);
  return IsValidStackAddress(state.sp) && IsValidStackAddress(state.fp) &&
      iterator_.SingletonFor(frame->GetCallerState(&state)) != NULL;
}


void SafeStackFrameIterator::Reset() {
  if (is_working_iterator_) {
    iterator_.Reset();
    iteration_done_ = false;
  }
}


// -------------------------------------------------------------------------


SafeStackTraceFrameIterator::SafeStackTraceFrameIterator(
    Isolate* isolate,
    Address fp, Address sp, Address low_bound, Address high_bound) :
    SafeJavaScriptFrameIterator(isolate, fp, sp, low_bound, high_bound) {
  if (!done() && !frame()->is_java_script()) Advance();
}


void SafeStackTraceFrameIterator::Advance() {
  while (true) {
    SafeJavaScriptFrameIterator::Advance();
    if (done()) return;
    if (frame()->is_java_script()) return;
  }
}


Code* StackFrame::GetSafepointData(Isolate* isolate,
                                   Address inner_pointer,
                                   SafepointEntry* safepoint_entry,
                                   unsigned* stack_slots) {
  InnerPointerToCodeCache::InnerPointerToCodeCacheEntry* entry =
      isolate->inner_pointer_to_code_cache()->GetCacheEntry(inner_pointer);
  if (!entry->safepoint_entry.is_valid()) {
    entry->safepoint_entry = entry->code->GetSafepointEntry(inner_pointer);
    ASSERT(entry->safepoint_entry.is_valid());
  } else {
    ASSERT(entry->safepoint_entry.Equals(
        entry->code->GetSafepointEntry(inner_pointer)));
  }

  // Fill in the results and return the code.
  Code* code = entry->code;
  *safepoint_entry = entry->safepoint_entry;
  *stack_slots = code->stack_slots();
  return code;
}


bool StackFrame::HasHandler() const {
  StackHandlerIterator it(this, top_handler());
  return !it.done();
}


#ifdef DEBUG
static bool GcSafeCodeContains(HeapObject* object, Address addr);
#endif


void StackFrame::IteratePc(ObjectVisitor* v,
                           Address* pc_address,
                           Code* holder) {
  Address pc = *pc_address;
  ASSERT(GcSafeCodeContains(holder, pc));
  unsigned pc_offset = static_cast<unsigned>(pc - holder->instruction_start());
  Object* code = holder;
  v->VisitPointer(&code);
  if (code != holder) {
    holder = reinterpret_cast<Code*>(code);
    pc = holder->instruction_start() + pc_offset;
    *pc_address = pc;
  }
}


void StackFrame::SetReturnAddressLocationResolver(
    ReturnAddressLocationResolver resolver) {
  ASSERT(return_address_location_resolver == NULL);
  return_address_location_resolver = resolver;
}


StackFrame::Type StackFrame::ComputeType(Isolate* isolate, State* state) {
  ASSERT(state->fp != NULL);
  if (StandardFrame::IsArgumentsAdaptorFrame(state->fp)) {
    return ARGUMENTS_ADAPTOR;
  }
  // The marker and function offsets overlap. If the marker isn't a
  // smi then the frame is a JavaScript frame -- and the marker is
  // really the function.
  const int offset = StandardFrameConstants::kMarkerOffset;
  Object* marker = Memory::Object_at(state->fp + offset);
  if (!marker->IsSmi()) {
    // If we're using a "safe" stack iterator, we treat optimized
    // frames as normal JavaScript frames to avoid having to look
    // into the heap to determine the state. This is safe as long
    // as nobody tries to GC...
    if (SafeStackFrameIterator::is_active(isolate)) return JAVA_SCRIPT;
    Code::Kind kind = GetContainingCode(isolate, *(state->pc_address))->kind();
    ASSERT(kind == Code::FUNCTION || kind == Code::OPTIMIZED_FUNCTION);
    return (kind == Code::OPTIMIZED_FUNCTION) ? OPTIMIZED : JAVA_SCRIPT;
  }
  return static_cast<StackFrame::Type>(Smi::cast(marker)->value());
}



StackFrame::Type StackFrame::GetCallerState(State* state) const {
  ComputeCallerState(state);
  return ComputeType(isolate(), state);
}


Address StackFrame::UnpaddedFP() const {
#if defined(V8_TARGET_ARCH_IA32)
  if (!is_optimized()) return fp();
  int32_t alignment_state = Memory::int32_at(
    fp() + JavaScriptFrameConstants::kDynamicAlignmentStateOffset);

  return (alignment_state == kAlignmentPaddingPushed) ?
    (fp() + kPointerSize) : fp();
#else
  return fp();
#endif
}


Code* EntryFrame::unchecked_code() const {
  return HEAP->raw_unchecked_js_entry_code();
}


void EntryFrame::ComputeCallerState(State* state) const {
  GetCallerState(state);
}


void EntryFrame::SetCallerFp(Address caller_fp) {
  const int offset = EntryFrameConstants::kCallerFPOffset;
  Memory::Address_at(this->fp() + offset) = caller_fp;
}


StackFrame::Type EntryFrame::GetCallerState(State* state) const {
  const int offset = EntryFrameConstants::kCallerFPOffset;
  Address fp = Memory::Address_at(this->fp() + offset);
  return ExitFrame::GetStateForFramePointer(fp, state);
}


Code* EntryConstructFrame::unchecked_code() const {
  return HEAP->raw_unchecked_js_construct_entry_code();
}


Object*& ExitFrame::code_slot() const {
  const int offset = ExitFrameConstants::kCodeOffset;
  return Memory::Object_at(fp() + offset);
}


Code* ExitFrame::unchecked_code() const {
  return reinterpret_cast<Code*>(code_slot());
}


void ExitFrame::ComputeCallerState(State* state) const {
  // Set up the caller state.
  state->sp = caller_sp();
  state->fp = Memory::Address_at(fp() + ExitFrameConstants::kCallerFPOffset);
  state->pc_address = ResolveReturnAddressLocation(
      reinterpret_cast<Address*>(fp() + ExitFrameConstants::kCallerPCOffset));
}


void ExitFrame::SetCallerFp(Address caller_fp) {
  Memory::Address_at(fp() + ExitFrameConstants::kCallerFPOffset) = caller_fp;
}


void ExitFrame::Iterate(ObjectVisitor* v) const {
  // The arguments are traversed as part of the expression stack of
  // the calling frame.
  IteratePc(v, pc_address(), LookupCode());
  v->VisitPointer(&code_slot());
}


Address ExitFrame::GetCallerStackPointer() const {
  return fp() + ExitFrameConstants::kCallerSPDisplacement;
}


StackFrame::Type ExitFrame::GetStateForFramePointer(Address fp, State* state) {
  if (fp == 0) return NONE;
  Address sp = ComputeStackPointer(fp);
  FillState(fp, sp, state);
  ASSERT(*state->pc_address != NULL);
  return EXIT;
}


void ExitFrame::FillState(Address fp, Address sp, State* state) {
  state->sp = sp;
  state->fp = fp;
  state->pc_address = ResolveReturnAddressLocation(
      reinterpret_cast<Address*>(sp - 1 * kPointerSize));
}


Address StandardFrame::GetExpressionAddress(int n) const {
  const int offset = StandardFrameConstants::kExpressionsOffset;
  return fp() + offset - n * kPointerSize;
}


Object* StandardFrame::GetExpression(Address fp, int index) {
  return Memory::Object_at(GetExpressionAddress(fp, index));
}


Address StandardFrame::GetExpressionAddress(Address fp, int n) {
  const int offset = StandardFrameConstants::kExpressionsOffset;
  return fp + offset - n * kPointerSize;
}


int StandardFrame::ComputeExpressionsCount() const {
  const int offset =
      StandardFrameConstants::kExpressionsOffset + kPointerSize;
  Address base = fp() + offset;
  Address limit = sp();
  ASSERT(base >= limit);  // stack grows downwards
  // Include register-allocated locals in number of expressions.
  return static_cast<int>((base - limit) / kPointerSize);
}


void StandardFrame::ComputeCallerState(State* state) const {
  state->sp = caller_sp();
  state->fp = caller_fp();
  state->pc_address = ResolveReturnAddressLocation(
      reinterpret_cast<Address*>(ComputePCAddress(fp())));
}


void StandardFrame::SetCallerFp(Address caller_fp) {
  Memory::Address_at(fp() + StandardFrameConstants::kCallerFPOffset) =
      caller_fp;
}


bool StandardFrame::IsExpressionInsideHandler(int n) const {
  Address address = GetExpressionAddress(n);
  for (StackHandlerIterator it(this, top_handler()); !it.done(); it.Advance()) {
    if (it.handler()->includes(address)) return true;
  }
  return false;
}


void OptimizedFrame::Iterate(ObjectVisitor* v) const {
#ifdef DEBUG
  // Make sure that optimized frames do not contain any stack handlers.
  StackHandlerIterator it(this, top_handler());
  ASSERT(it.done());
#endif

  // Make sure that we're not doing "safe" stack frame iteration. We cannot
  // possibly find pointers in optimized frames in that state.
  ASSERT(!SafeStackFrameIterator::is_active(isolate()));

  // Compute the safepoint information.
  unsigned stack_slots = 0;
  SafepointEntry safepoint_entry;
  Code* code = StackFrame::GetSafepointData(
      isolate(), pc(), &safepoint_entry, &stack_slots);
  unsigned slot_space = stack_slots * kPointerSize;

  // Visit the outgoing parameters.
  Object** parameters_base = &Memory::Object_at(sp());
  Object** parameters_limit = &Memory::Object_at(
      fp() + JavaScriptFrameConstants::kFunctionOffset - slot_space);

  // Visit the parameters that may be on top of the saved registers.
  if (safepoint_entry.argument_count() > 0) {
    v->VisitPointers(parameters_base,
                     parameters_base + safepoint_entry.argument_count());
    parameters_base += safepoint_entry.argument_count();
  }

  // Skip saved double registers.
  if (safepoint_entry.has_doubles()) {
    parameters_base += DoubleRegister::kNumAllocatableRegisters *
        kDoubleSize / kPointerSize;
  }

  // Visit the registers that contain pointers if any.
  if (safepoint_entry.HasRegisters()) {
    for (int i = kNumSafepointRegisters - 1; i >=0; i--) {
      if (safepoint_entry.HasRegisterAt(i)) {
        int reg_stack_index = MacroAssembler::SafepointRegisterStackIndex(i);
        v->VisitPointer(parameters_base + reg_stack_index);
      }
    }
    // Skip the words containing the register values.
    parameters_base += kNumSafepointRegisters;
  }

  // We're done dealing with the register bits.
  uint8_t* safepoint_bits = safepoint_entry.bits();
  safepoint_bits += kNumSafepointRegisters >> kBitsPerByteLog2;

  // Visit the rest of the parameters.
  v->VisitPointers(parameters_base, parameters_limit);

  // Visit pointer spill slots and locals.
  for (unsigned index = 0; index < stack_slots; index++) {
    int byte_index = index >> kBitsPerByteLog2;
    int bit_index = index & (kBitsPerByte - 1);
    if ((safepoint_bits[byte_index] & (1U << bit_index)) != 0) {
      v->VisitPointer(parameters_limit + index);
    }
  }

  // Visit the context and the function.
  Object** fixed_base = &Memory::Object_at(
      fp() + JavaScriptFrameConstants::kFunctionOffset);
  Object** fixed_limit = &Memory::Object_at(fp());
  v->VisitPointers(fixed_base, fixed_limit);

  // Visit the return address in the callee and incoming arguments.
  IteratePc(v, pc_address(), code);
}


bool JavaScriptFrame::IsConstructor() const {
  Address fp = caller_fp();
  if (has_adapted_arguments()) {
    // Skip the arguments adaptor frame and look at the real caller.
    fp = Memory::Address_at(fp + StandardFrameConstants::kCallerFPOffset);
  }
  return IsConstructFrame(fp);
}


int JavaScriptFrame::GetArgumentsLength() const {
  // If there is an arguments adaptor frame get the arguments length from it.
  if (has_adapted_arguments()) {
    return Smi::cast(GetExpression(caller_fp(), 0))->value();
  } else {
    return GetNumberOfIncomingArguments();
  }
}


Code* JavaScriptFrame::unchecked_code() const {
  JSFunction* function = JSFunction::cast(this->function());
  return function->unchecked_code();
}


int JavaScriptFrame::GetNumberOfIncomingArguments() const {
  ASSERT(!SafeStackFrameIterator::is_active(isolate()) &&
         isolate()->heap()->gc_state() == Heap::NOT_IN_GC);

  JSFunction* function = JSFunction::cast(this->function());
  return function->shared()->formal_parameter_count();
}


Address JavaScriptFrame::GetCallerStackPointer() const {
  return fp() + StandardFrameConstants::kCallerSPOffset;
}


void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) {
  ASSERT(functions->length() == 0);
  functions->Add(JSFunction::cast(function()));
}


void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
  ASSERT(functions->length() == 0);
  Code* code_pointer = LookupCode();
  int offset = static_cast<int>(pc() - code_pointer->address());
  FrameSummary summary(receiver(),
                       JSFunction::cast(function()),
                       code_pointer,
                       offset,
                       IsConstructor());
  functions->Add(summary);
}


void JavaScriptFrame::PrintTop(FILE* file,
                               bool print_args,
                               bool print_line_number) {
  // constructor calls
  HandleScope scope;
  AssertNoAllocation no_allocation;
  JavaScriptFrameIterator it;
  while (!it.done()) {
    if (it.frame()->is_java_script()) {
      JavaScriptFrame* frame = it.frame();
      if (frame->IsConstructor()) PrintF(file, "new ");
      // function name
      Object* maybe_fun = frame->function();
      if (maybe_fun->IsJSFunction()) {
        JSFunction* fun = JSFunction::cast(maybe_fun);
        fun->PrintName();
        Code* js_code = frame->unchecked_code();
        Address pc = frame->pc();
        int code_offset =
            static_cast<int>(pc - js_code->instruction_start());
        PrintF("+%d", code_offset);
        SharedFunctionInfo* shared = fun->shared();
        if (print_line_number) {
          Code* code = Code::cast(
              v8::internal::Isolate::Current()->heap()->FindCodeObject(pc));
          int source_pos = code->SourcePosition(pc);
          Object* maybe_script = shared->script();
          if (maybe_script->IsScript()) {
            Handle<Script> script(Script::cast(maybe_script));
            int line = GetScriptLineNumberSafe(script, source_pos) + 1;
            Object* script_name_raw = script->name();
            if (script_name_raw->IsString()) {
              String* script_name = String::cast(script->name());
              SmartArrayPointer<char> c_script_name =
                  script_name->ToCString(DISALLOW_NULLS,
                                         ROBUST_STRING_TRAVERSAL);
              PrintF(file, " at %s:%d", *c_script_name, line);
            } else {
              PrintF(file, "at <unknown>:%d", line);
            }
          } else {
            PrintF(file, " at <unknown>:<unknown>");
          }
        }
      } else {
        PrintF("<unknown>");
      }

      if (print_args) {
        // function arguments
        // (we are intentionally only printing the actually
        // supplied parameters, not all parameters required)
        PrintF(file, "(this=");
        frame->receiver()->ShortPrint(file);
        const int length = frame->ComputeParametersCount();
        for (int i = 0; i < length; i++) {
          PrintF(file, ", ");
          frame->GetParameter(i)->ShortPrint(file);
        }
        PrintF(file, ")");
      }
      break;
    }
    it.Advance();
  }
}


void FrameSummary::Print() {
  PrintF("receiver: ");
  receiver_->ShortPrint();
  PrintF("\nfunction: ");
  function_->shared()->DebugName()->ShortPrint();
  PrintF("\ncode: ");
  code_->ShortPrint();
  if (code_->kind() == Code::FUNCTION) PrintF(" NON-OPT");
  if (code_->kind() == Code::OPTIMIZED_FUNCTION) PrintF(" OPT");
  PrintF("\npc: %d\n", offset_);
}


JSFunction* OptimizedFrame::LiteralAt(FixedArray* literal_array,
                                      int literal_id) {
  if (literal_id == Translation::kSelfLiteralId) {
    return JSFunction::cast(function());
  }

  return JSFunction::cast(literal_array->get(literal_id));
}


void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
  ASSERT(frames->length() == 0);
  ASSERT(is_optimized());

  int deopt_index = Safepoint::kNoDeoptimizationIndex;
  DeoptimizationInputData* data = GetDeoptimizationData(&deopt_index);
  FixedArray* literal_array = data->LiteralArray();

  // BUG(3243555): Since we don't have a lazy-deopt registered at
  // throw-statements, we can't use the translation at the call-site of
  // throw. An entry with no deoptimization index indicates a call-site
  // without a lazy-deopt. As a consequence we are not allowed to inline
  // functions containing throw.
  if (deopt_index == Safepoint::kNoDeoptimizationIndex) {
    JavaScriptFrame::Summarize(frames);
    return;
  }

  TranslationIterator it(data->TranslationByteArray(),
                         data->TranslationIndex(deopt_index)->value());
  Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
  ASSERT(opcode == Translation::BEGIN);
  it.Next();  // Drop frame count.
  int jsframe_count = it.Next();

  // We create the summary in reverse order because the frames
  // in the deoptimization translation are ordered bottom-to-top.
  bool is_constructor = IsConstructor();
  int i = jsframe_count;
  while (i > 0) {
    opcode = static_cast<Translation::Opcode>(it.Next());
    if (opcode == Translation::JS_FRAME) {
      i--;
      int ast_id = it.Next();
      JSFunction* function = LiteralAt(literal_array, it.Next());
      it.Next();  // Skip height.

      // The translation commands are ordered and the receiver is always
      // at the first position. Since we are always at a call when we need
      // to construct a stack trace, the receiver is always in a stack slot.
      opcode = static_cast<Translation::Opcode>(it.Next());
      ASSERT(opcode == Translation::STACK_SLOT ||
             opcode == Translation::LITERAL);
      int index = it.Next();

      // Get the correct receiver in the optimized frame.
      Object* receiver = NULL;
      if (opcode == Translation::LITERAL) {
        receiver = data->LiteralArray()->get(index);
      } else {
        // Positive index means the value is spilled to the locals
        // area. Negative means it is stored in the incoming parameter
        // area.
        if (index >= 0) {
          receiver = GetExpression(index);
        } else {
          // Index -1 overlaps with last parameter, -n with the first parameter,
          // (-n - 1) with the receiver with n being the number of parameters
          // of the outermost, optimized frame.
          int parameter_count = ComputeParametersCount();
          int parameter_index = index + parameter_count;
          receiver = (parameter_index == -1)
              ? this->receiver()
              : this->GetParameter(parameter_index);
        }
      }

      Code* code = function->shared()->code();
      DeoptimizationOutputData* output_data =
          DeoptimizationOutputData::cast(code->deoptimization_data());
      unsigned entry = Deoptimizer::GetOutputInfo(output_data,
                                                  ast_id,
                                                  function->shared());
      unsigned pc_offset =
          FullCodeGenerator::PcField::decode(entry) + Code::kHeaderSize;
      ASSERT(pc_offset > 0);

      FrameSummary summary(receiver, function, code, pc_offset, is_constructor);
      frames->Add(summary);
      is_constructor = false;
    } else if (opcode == Translation::CONSTRUCT_STUB_FRAME) {
      // The next encountered JS_FRAME will be marked as a constructor call.
      it.Skip(Translation::NumberOfOperandsFor(opcode));
      ASSERT(!is_constructor);
      is_constructor = true;
    } else {
      // Skip over operands to advance to the next opcode.
      it.Skip(Translation::NumberOfOperandsFor(opcode));
    }
  }
  ASSERT(!is_constructor);
}


DeoptimizationInputData* OptimizedFrame::GetDeoptimizationData(
    int* deopt_index) {
  ASSERT(is_optimized());

  JSFunction* opt_function = JSFunction::cast(function());
  Code* code = opt_function->code();

  // The code object may have been replaced by lazy deoptimization. Fall
  // back to a slow search in this case to find the original optimized
  // code object.
  if (!code->contains(pc())) {
    code = isolate()->inner_pointer_to_code_cache()->
        GcSafeFindCodeForInnerPointer(pc());
  }
  ASSERT(code != NULL);
  ASSERT(code->kind() == Code::OPTIMIZED_FUNCTION);

  SafepointEntry safepoint_entry = code->GetSafepointEntry(pc());
  *deopt_index = safepoint_entry.deoptimization_index();
  ASSERT(*deopt_index != Safepoint::kNoDeoptimizationIndex);

  return DeoptimizationInputData::cast(code->deoptimization_data());
}


int OptimizedFrame::GetInlineCount() {
  ASSERT(is_optimized());

  int deopt_index = Safepoint::kNoDeoptimizationIndex;
  DeoptimizationInputData* data = GetDeoptimizationData(&deopt_index);

  TranslationIterator it(data->TranslationByteArray(),
                         data->TranslationIndex(deopt_index)->value());
  Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
  ASSERT(opcode == Translation::BEGIN);
  USE(opcode);
  it.Next();  // Drop frame count.
  int jsframe_count = it.Next();
  return jsframe_count;
}


void OptimizedFrame::GetFunctions(List<JSFunction*>* functions) {
  ASSERT(functions->length() == 0);
  ASSERT(is_optimized());

  int deopt_index = Safepoint::kNoDeoptimizationIndex;
  DeoptimizationInputData* data = GetDeoptimizationData(&deopt_index);
  FixedArray* literal_array = data->LiteralArray();

  TranslationIterator it(data->TranslationByteArray(),
                         data->TranslationIndex(deopt_index)->value());
  Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
  ASSERT(opcode == Translation::BEGIN);
  it.Next();  // Drop frame count.
  int jsframe_count = it.Next();

  // We insert the frames in reverse order because the frames
  // in the deoptimization translation are ordered bottom-to-top.
  while (jsframe_count > 0) {
    opcode = static_cast<Translation::Opcode>(it.Next());
    if (opcode == Translation::JS_FRAME) {
      jsframe_count--;
      it.Next();  // Skip ast id.
      JSFunction* function = LiteralAt(literal_array, it.Next());
      it.Next();  // Skip height.
      functions->Add(function);
    } else {
      // Skip over operands to advance to the next opcode.
      it.Skip(Translation::NumberOfOperandsFor(opcode));
    }
  }
}


int ArgumentsAdaptorFrame::GetNumberOfIncomingArguments() const {
  return Smi::cast(GetExpression(0))->value();
}


Address ArgumentsAdaptorFrame::GetCallerStackPointer() const {
  return fp() + StandardFrameConstants::kCallerSPOffset;
}


Address InternalFrame::GetCallerStackPointer() const {
  // Internal frames have no arguments. The stack pointer of the
  // caller is at a fixed offset from the frame pointer.
  return fp() + StandardFrameConstants::kCallerSPOffset;
}


Code* ArgumentsAdaptorFrame::unchecked_code() const {
  return isolate()->builtins()->builtin(
      Builtins::kArgumentsAdaptorTrampoline);
}


Code* InternalFrame::unchecked_code() const {
  const int offset = InternalFrameConstants::kCodeOffset;
  Object* code = Memory::Object_at(fp() + offset);
  ASSERT(code != NULL);
  return reinterpret_cast<Code*>(code);
}


void StackFrame::PrintIndex(StringStream* accumulator,
                            PrintMode mode,
                            int index) {
  accumulator->Add((mode == OVERVIEW) ? "%5d: " : "[%d]: ", index);
}


void JavaScriptFrame::Print(StringStream* accumulator,
                            PrintMode mode,
                            int index) const {
  HandleScope scope;
  Object* receiver = this->receiver();
  Object* function = this->function();

  accumulator->PrintSecurityTokenIfChanged(function);
  PrintIndex(accumulator, mode, index);
  Code* code = NULL;
  if (IsConstructor()) accumulator->Add("new ");
  accumulator->PrintFunction(function, receiver, &code);

  // Get scope information for nicer output, if possible. If code is NULL, or
  // doesn't contain scope info, scope_info will return 0 for the number of
  // parameters, stack local variables, context local variables, stack slots,
  // or context slots.
  Handle<ScopeInfo> scope_info(ScopeInfo::Empty());

  if (function->IsJSFunction()) {
    Handle<SharedFunctionInfo> shared(JSFunction::cast(function)->shared());
    scope_info = Handle<ScopeInfo>(shared->scope_info());
    Object* script_obj = shared->script();
    if (script_obj->IsScript()) {
      Handle<Script> script(Script::cast(script_obj));
      accumulator->Add(" [");
      accumulator->PrintName(script->name());

      Address pc = this->pc();
      if (code != NULL && code->kind() == Code::FUNCTION &&
          pc >= code->instruction_start() && pc < code->instruction_end()) {
        int source_pos = code->SourcePosition(pc);
        int line = GetScriptLineNumberSafe(script, source_pos) + 1;
        accumulator->Add(":%d", line);
      } else {
        int function_start_pos = shared->start_position();
        int line = GetScriptLineNumberSafe(script, function_start_pos) + 1;
        accumulator->Add(":~%d", line);
      }

      accumulator->Add("] ");
    }
  }

  accumulator->Add("(this=%o", receiver);

  // Print the parameters.
  int parameters_count = ComputeParametersCount();
  for (int i = 0; i < parameters_count; i++) {
    accumulator->Add(",");
    // If we have a name for the parameter we print it. Nameless
    // parameters are either because we have more actual parameters
    // than formal parameters or because we have no scope information.
    if (i < scope_info->ParameterCount()) {
      accumulator->PrintName(scope_info->ParameterName(i));
      accumulator->Add("=");
    }
    accumulator->Add("%o", GetParameter(i));
  }

  accumulator->Add(")");
  if (mode == OVERVIEW) {
    accumulator->Add("\n");
    return;
  }
  if (is_optimized()) {
    accumulator->Add(" {\n// optimized frame\n}\n");
    return;
  }
  accumulator->Add(" {\n");

  // Compute the number of locals and expression stack elements.
  int stack_locals_count = scope_info->StackLocalCount();
  int heap_locals_count = scope_info->ContextLocalCount();
  int expressions_count = ComputeExpressionsCount();

  // Print stack-allocated local variables.
  if (stack_locals_count > 0) {
    accumulator->Add("  // stack-allocated locals\n");
  }
  for (int i = 0; i < stack_locals_count; i++) {
    accumulator->Add("  var ");
    accumulator->PrintName(scope_info->StackLocalName(i));
    accumulator->Add(" = ");
    if (i < expressions_count) {
      accumulator->Add("%o", GetExpression(i));
    } else {
      accumulator->Add("// no expression found - inconsistent frame?");
    }
    accumulator->Add("\n");
  }

  // Try to get hold of the context of this frame.
  Context* context = NULL;
  if (this->context() != NULL && this->context()->IsContext()) {
    context = Context::cast(this->context());
  }

  // Print heap-allocated local variables.
  if (heap_locals_count > 0) {
    accumulator->Add("  // heap-allocated locals\n");
  }
  for (int i = 0; i < heap_locals_count; i++) {
    accumulator->Add("  var ");
    accumulator->PrintName(scope_info->ContextLocalName(i));
    accumulator->Add(" = ");
    if (context != NULL) {
      if (i < context->length()) {
        accumulator->Add("%o", context->get(Context::MIN_CONTEXT_SLOTS + i));
      } else {
        accumulator->Add(
            "// warning: missing context slot - inconsistent frame?");
      }
    } else {
      accumulator->Add("// warning: no context found - inconsistent frame?");
    }
    accumulator->Add("\n");
  }

  // Print the expression stack.
  int expressions_start = stack_locals_count;
  if (expressions_start < expressions_count) {
    accumulator->Add("  // expression stack (top to bottom)\n");
  }
  for (int i = expressions_count - 1; i >= expressions_start; i--) {
    if (IsExpressionInsideHandler(i)) continue;
    accumulator->Add("  [%02d] : %o\n", i, GetExpression(i));
  }

  // Print details about the function.
  if (FLAG_max_stack_trace_source_length != 0 && code != NULL) {
    SharedFunctionInfo* shared = JSFunction::cast(function)->shared();
    accumulator->Add("--------- s o u r c e   c o d e ---------\n");
    shared->SourceCodePrint(accumulator, FLAG_max_stack_trace_source_length);
    accumulator->Add("\n-----------------------------------------\n");
  }

  accumulator->Add("}\n\n");
}


void ArgumentsAdaptorFrame::Print(StringStream* accumulator,
                                  PrintMode mode,
                                  int index) const {
  int actual = ComputeParametersCount();
  int expected = -1;
  Object* function = this->function();
  if (function->IsJSFunction()) {
    expected = JSFunction::cast(function)->shared()->formal_parameter_count();
  }

  PrintIndex(accumulator, mode, index);
  accumulator->Add("arguments adaptor frame: %d->%d", actual, expected);
  if (mode == OVERVIEW) {
    accumulator->Add("\n");
    return;
  }
  accumulator->Add(" {\n");

  // Print actual arguments.
  if (actual > 0) accumulator->Add("  // actual arguments\n");
  for (int i = 0; i < actual; i++) {
    accumulator->Add("  [%02d] : %o", i, GetParameter(i));
    if (expected != -1 && i >= expected) {
      accumulator->Add("  // not passed to callee");
    }
    accumulator->Add("\n");
  }

  accumulator->Add("}\n\n");
}


void EntryFrame::Iterate(ObjectVisitor* v) const {
  StackHandlerIterator it(this, top_handler());
  ASSERT(!it.done());
  StackHandler* handler = it.handler();
  ASSERT(handler->is_js_entry());
  handler->Iterate(v, LookupCode());
#ifdef DEBUG
  // Make sure that the entry frame does not contain more than one
  // stack handler.
  it.Advance();
  ASSERT(it.done());
#endif
  IteratePc(v, pc_address(), LookupCode());
}


void StandardFrame::IterateExpressions(ObjectVisitor* v) const {
  const int offset = StandardFrameConstants::kContextOffset;
  Object** base = &Memory::Object_at(sp());
  Object** limit = &Memory::Object_at(fp() + offset) + 1;
  for (StackHandlerIterator it(this, top_handler()); !it.done(); it.Advance()) {
    StackHandler* handler = it.handler();
    // Traverse pointers down to - but not including - the next
    // handler in the handler chain. Update the base to skip the
    // handler and allow the handler to traverse its own pointers.
    const Address address = handler->address();
    v->VisitPointers(base, reinterpret_cast<Object**>(address));
    base = reinterpret_cast<Object**>(address + StackHandlerConstants::kSize);
    // Traverse the pointers in the handler itself.
    handler->Iterate(v, LookupCode());
  }
  v->VisitPointers(base, limit);
}


void JavaScriptFrame::Iterate(ObjectVisitor* v) const {
  IterateExpressions(v);
  IteratePc(v, pc_address(), LookupCode());
}


void InternalFrame::Iterate(ObjectVisitor* v) const {
  // Internal frames only have object pointers on the expression stack
  // as they never have any arguments.
  IterateExpressions(v);
  IteratePc(v, pc_address(), LookupCode());
}


// -------------------------------------------------------------------------


JavaScriptFrame* StackFrameLocator::FindJavaScriptFrame(int n) {
  ASSERT(n >= 0);
  for (int i = 0; i <= n; i++) {
    while (!iterator_.frame()->is_java_script()) iterator_.Advance();
    if (i == n) return JavaScriptFrame::cast(iterator_.frame());
    iterator_.Advance();
  }
  UNREACHABLE();
  return NULL;
}


// -------------------------------------------------------------------------


static Map* GcSafeMapOfCodeSpaceObject(HeapObject* object) {
  MapWord map_word = object->map_word();
  return map_word.IsForwardingAddress() ?
      map_word.ToForwardingAddress()->map() : map_word.ToMap();
}


static int GcSafeSizeOfCodeSpaceObject(HeapObject* object) {
  return object->SizeFromMap(GcSafeMapOfCodeSpaceObject(object));
}


#ifdef DEBUG
static bool GcSafeCodeContains(HeapObject* code, Address addr) {
  Map* map = GcSafeMapOfCodeSpaceObject(code);
  ASSERT(map == code->GetHeap()->code_map());
  Address start = code->address();
  Address end = code->address() + code->SizeFromMap(map);
  return start <= addr && addr < end;
}
#endif


Code* InnerPointerToCodeCache::GcSafeCastToCode(HeapObject* object,
                                                Address inner_pointer) {
  Code* code = reinterpret_cast<Code*>(object);
  ASSERT(code != NULL && GcSafeCodeContains(code, inner_pointer));
  return code;
}


Code* InnerPointerToCodeCache::GcSafeFindCodeForInnerPointer(
    Address inner_pointer) {
  Heap* heap = isolate_->heap();
  // Check if the inner pointer points into a large object chunk.
  LargePage* large_page = heap->lo_space()->FindPage(inner_pointer);
  if (large_page != NULL) {
    return GcSafeCastToCode(large_page->GetObject(), inner_pointer);
  }

  // Iterate through the page until we reach the end or find an object starting
  // after the inner pointer.
  Page* page = Page::FromAddress(inner_pointer);

  Address addr = page->skip_list()->StartFor(inner_pointer);

  Address top = heap->code_space()->top();
  Address limit = heap->code_space()->limit();

  while (true) {
    if (addr == top && addr != limit) {
      addr = limit;
      continue;
    }

    HeapObject* obj = HeapObject::FromAddress(addr);
    int obj_size = GcSafeSizeOfCodeSpaceObject(obj);
    Address next_addr = addr + obj_size;
    if (next_addr > inner_pointer) return GcSafeCastToCode(obj, inner_pointer);
    addr = next_addr;
  }
}


InnerPointerToCodeCache::InnerPointerToCodeCacheEntry*
    InnerPointerToCodeCache::GetCacheEntry(Address inner_pointer) {
  isolate_->counters()->pc_to_code()->Increment();
  ASSERT(IsPowerOf2(kInnerPointerToCodeCacheSize));
  uint32_t hash = ComputeIntegerHash(
      static_cast<uint32_t>(reinterpret_cast<uintptr_t>(inner_pointer)),
      v8::internal::kZeroHashSeed);
  uint32_t index = hash & (kInnerPointerToCodeCacheSize - 1);
  InnerPointerToCodeCacheEntry* entry = cache(index);
  if (entry->inner_pointer == inner_pointer) {
    isolate_->counters()->pc_to_code_cached()->Increment();
    ASSERT(entry->code == GcSafeFindCodeForInnerPointer(inner_pointer));
  } else {
    // Because this code may be interrupted by a profiling signal that
    // also queries the cache, we cannot update inner_pointer before the code
    // has been set. Otherwise, we risk trying to use a cache entry before
    // the code has been computed.
    entry->code = GcSafeFindCodeForInnerPointer(inner_pointer);
    entry->safepoint_entry.Reset();
    entry->inner_pointer = inner_pointer;
  }
  return entry;
}


// -------------------------------------------------------------------------

int NumRegs(RegList reglist) {
  return CompilerIntrinsics::CountSetBits(reglist);
}


struct JSCallerSavedCodeData {
  int reg_code[kNumJSCallerSaved];
};

JSCallerSavedCodeData caller_saved_code_data;

void SetUpJSCallerSavedCodeData() {
  int i = 0;
  for (int r = 0; r < kNumRegs; r++)
    if ((kJSCallerSaved & (1 << r)) != 0)
      caller_saved_code_data.reg_code[i++] = r;

  ASSERT(i == kNumJSCallerSaved);
}

int JSCallerSavedCode(int n) {
  ASSERT(0 <= n && n < kNumJSCallerSaved);
  return caller_saved_code_data.reg_code[n];
}


#define DEFINE_WRAPPER(type, field)                              \
class field##_Wrapper : public ZoneObject {                      \
 public:  /* NOLINT */                                           \
  field##_Wrapper(const field& original) : frame_(original) {    \
  }                                                              \
  field frame_;                                                  \
};
STACK_FRAME_TYPE_LIST(DEFINE_WRAPPER)
#undef DEFINE_WRAPPER

static StackFrame* AllocateFrameCopy(StackFrame* frame, Zone* zone) {
#define FRAME_TYPE_CASE(type, field) \
  case StackFrame::type: { \
    field##_Wrapper* wrapper = \
        new(zone) field##_Wrapper(*(reinterpret_cast<field*>(frame))); \
    return &wrapper->frame_; \
  }

  switch (frame->type()) {
    STACK_FRAME_TYPE_LIST(FRAME_TYPE_CASE)
    default: UNREACHABLE();
  }
#undef FRAME_TYPE_CASE
  return NULL;
}

Vector<StackFrame*> CreateStackMap(Zone* zone) {
  ZoneList<StackFrame*> list(10, zone);
  for (StackFrameIterator it; !it.done(); it.Advance()) {
    StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
    list.Add(frame, zone);
  }
  return list.ToVector();
}


} }  // namespace v8::internal

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