// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/v8.h"
#include "src/ast.h"
#include "src/base/bits.h"
#include "src/deoptimizer.h"
#include "src/frames-inl.h"
#include "src/full-codegen.h"
#include "src/heap/mark-compact.h"
#include "src/safepoint-table.h"
#include "src/scopeinfo.h"
#include "src/string-stream.h"
#include "src/vm-state-inl.h"
namespace v8 {
namespace internal {
ReturnAddressLocationResolver
StackFrame::return_address_location_resolver_ = NULL;
// 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.
DCHECK(frame->sp() <= handler->address());
}
StackHandler* handler() const { return handler_; }
bool done() {
return handler_ == NULL || handler_->address() > limit_;
}
void Advance() {
DCHECK(!done());
handler_ = handler_->next();
}
private:
const Address limit_;
StackHandler* handler_;
};
// -------------------------------------------------------------------------
#define INITIALIZE_SINGLETON(type, field) field##_(this),
StackFrameIteratorBase::StackFrameIteratorBase(Isolate* isolate,
bool can_access_heap_objects)
: isolate_(isolate),
STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
frame_(NULL), handler_(NULL),
can_access_heap_objects_(can_access_heap_objects) {
}
#undef INITIALIZE_SINGLETON
StackFrameIterator::StackFrameIterator(Isolate* isolate)
: StackFrameIteratorBase(isolate, true) {
Reset(isolate->thread_local_top());
}
StackFrameIterator::StackFrameIterator(Isolate* isolate, ThreadLocalTop* t)
: StackFrameIteratorBase(isolate, true) {
Reset(t);
}
void StackFrameIterator::Advance() {
DCHECK(!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.
DCHECK(!done() || handler_ == NULL);
}
void StackFrameIterator::Reset(ThreadLocalTop* top) {
StackFrame::State state;
StackFrame::Type type = ExitFrame::GetStateForFramePointer(
Isolate::c_entry_fp(top), &state);
handler_ = StackHandler::FromAddress(Isolate::handler(top));
if (SingletonFor(type) == NULL) return;
frame_ = SingletonFor(type, &state);
}
StackFrame* StackFrameIteratorBase::SingletonFor(StackFrame::Type type,
StackFrame::State* state) {
if (type == StackFrame::NONE) return NULL;
StackFrame* result = SingletonFor(type);
DCHECK(result != NULL);
result->state_ = *state;
return result;
}
StackFrame* StackFrameIteratorBase::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
}
// -------------------------------------------------------------------------
JavaScriptFrameIterator::JavaScriptFrameIterator(
Isolate* isolate, StackFrame::Id id)
: iterator_(isolate) {
while (!done()) {
Advance();
if (frame()->id() == id) return;
}
}
void JavaScriptFrameIterator::Advance() {
do {
iterator_.Advance();
} while (!iterator_.done() && !iterator_.frame()->is_java_script());
}
void JavaScriptFrameIterator::AdvanceToArgumentsFrame() {
if (!frame()->has_adapted_arguments()) return;
iterator_.Advance();
DCHECK(iterator_.frame()->is_arguments_adaptor());
}
// -------------------------------------------------------------------------
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 = frame()->function()->shared()->script();
// Don't show functions from native scripts to user.
return (script->IsScript() &&
Script::TYPE_NATIVE != Script::cast(script)->type()->value());
}
// -------------------------------------------------------------------------
SafeStackFrameIterator::SafeStackFrameIterator(
Isolate* isolate,
Address fp, Address sp, Address js_entry_sp)
: StackFrameIteratorBase(isolate, false),
low_bound_(sp),
high_bound_(js_entry_sp),
top_frame_type_(StackFrame::NONE),
external_callback_scope_(isolate->external_callback_scope()) {
StackFrame::State state;
StackFrame::Type type;
ThreadLocalTop* top = isolate->thread_local_top();
if (IsValidTop(top)) {
type = ExitFrame::GetStateForFramePointer(Isolate::c_entry_fp(top), &state);
top_frame_type_ = type;
} else if (IsValidStackAddress(fp)) {
DCHECK(fp != NULL);
state.fp = fp;
state.sp = sp;
state.pc_address = StackFrame::ResolveReturnAddressLocation(
reinterpret_cast<Address*>(StandardFrame::ComputePCAddress(fp)));
// StackFrame::ComputeType will read both kContextOffset and kMarkerOffset,
// we check only that kMarkerOffset is within the stack bounds and do
// compile time check that kContextOffset slot is pushed on the stack before
// kMarkerOffset.
STATIC_ASSERT(StandardFrameConstants::kMarkerOffset <
StandardFrameConstants::kContextOffset);
Address frame_marker = fp + StandardFrameConstants::kMarkerOffset;
if (IsValidStackAddress(frame_marker)) {
type = StackFrame::ComputeType(this, &state);
top_frame_type_ = type;
} else {
// Mark the frame as JAVA_SCRIPT if we cannot determine its type.
// The frame anyways will be skipped.
type = StackFrame::JAVA_SCRIPT;
// Top frame is incomplete so we cannot reliably determine its type.
top_frame_type_ = StackFrame::NONE;
}
} else {
return;
}
if (SingletonFor(type) == NULL) return;
frame_ = SingletonFor(type, &state);
if (frame_ == NULL) return;
Advance();
if (frame_ != NULL && !frame_->is_exit() &&
external_callback_scope_ != NULL &&
external_callback_scope_->scope_address() < frame_->fp()) {
// Skip top ExternalCallbackScope if we already advanced to a JS frame
// under it. Sampler will anyways take this top external callback.
external_callback_scope_ = external_callback_scope_->previous();
}
}
bool SafeStackFrameIterator::IsValidTop(ThreadLocalTop* top) const {
Address c_entry_fp = Isolate::c_entry_fp(top);
if (!IsValidExitFrame(c_entry_fp)) return false;
// There should be at least one JS_ENTRY stack handler.
Address handler = Isolate::handler(top);
if (handler == NULL) return false;
// Check that there are no js frames on top of the native frames.
return c_entry_fp < handler;
}
void SafeStackFrameIterator::AdvanceOneFrame() {
DCHECK(!done());
StackFrame* last_frame = frame_;
Address last_sp = last_frame->sp(), last_fp = last_frame->fp();
// Before advancing to the next stack frame, perform pointer validity tests.
if (!IsValidFrame(last_frame) || !IsValidCaller(last_frame)) {
frame_ = NULL;
return;
}
// Advance to the previous frame.
StackFrame::State state;
StackFrame::Type type = frame_->GetCallerState(&state);
frame_ = SingletonFor(type, &state);
if (frame_ == NULL) return;
// Check that we have actually moved to the previous frame in the stack.
if (frame_->sp() < last_sp || frame_->fp() < last_fp) {
frame_ = NULL;
}
}
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);
if (!IsValidExitFrame(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) &&
SingletonFor(frame->GetCallerState(&state)) != NULL;
}
bool SafeStackFrameIterator::IsValidExitFrame(Address fp) const {
if (!IsValidStackAddress(fp)) return false;
Address sp = ExitFrame::ComputeStackPointer(fp);
if (!IsValidStackAddress(sp)) return false;
StackFrame::State state;
ExitFrame::FillState(fp, sp, &state);
if (!IsValidStackAddress(reinterpret_cast<Address>(state.pc_address))) {
return false;
}
return *state.pc_address != NULL;
}
void SafeStackFrameIterator::Advance() {
while (true) {
AdvanceOneFrame();
if (done()) return;
if (frame_->is_java_script()) return;
if (frame_->is_exit() && external_callback_scope_) {
// Some of the EXIT frames may have ExternalCallbackScope allocated on
// top of them. In that case the scope corresponds to the first EXIT
// frame beneath it. There may be other EXIT frames on top of the
// ExternalCallbackScope, just skip them as we cannot collect any useful
// information about them.
if (external_callback_scope_->scope_address() < frame_->fp()) {
Address* callback_address =
external_callback_scope_->callback_address();
if (*callback_address != NULL) {
frame_->state_.pc_address = callback_address;
}
external_callback_scope_ = external_callback_scope_->previous();
DCHECK(external_callback_scope_ == NULL ||
external_callback_scope_->scope_address() > frame_->fp());
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);
DCHECK(entry->safepoint_entry.is_valid());
} else {
DCHECK(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;
DCHECK(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) {
DCHECK(return_address_location_resolver_ == NULL);
return_address_location_resolver_ = resolver;
}
StackFrame::Type StackFrame::ComputeType(const StackFrameIteratorBase* iterator,
State* state) {
DCHECK(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 (!iterator->can_access_heap_objects_) return JAVA_SCRIPT;
Code::Kind kind = GetContainingCode(iterator->isolate(),
*(state->pc_address))->kind();
DCHECK(kind == Code::FUNCTION || kind == Code::OPTIMIZED_FUNCTION);
return (kind == Code::OPTIMIZED_FUNCTION) ? OPTIMIZED : JAVA_SCRIPT;
}
return static_cast<StackFrame::Type>(Smi::cast(marker)->value());
}
#ifdef DEBUG
bool StackFrame::can_access_heap_objects() const {
return iterator_->can_access_heap_objects_;
}
#endif
StackFrame::Type StackFrame::GetCallerState(State* state) const {
ComputeCallerState(state);
return ComputeType(iterator_, state);
}
Address StackFrame::UnpaddedFP() const {
#if V8_TARGET_ARCH_IA32 || V8_TARGET_ARCH_X87
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 isolate()->heap()->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 isolate()->heap()->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));
if (FLAG_enable_ool_constant_pool) {
state->constant_pool_address = reinterpret_cast<Address*>(
fp() + ExitFrameConstants::kConstantPoolOffset);
}
}
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());
if (FLAG_enable_ool_constant_pool) {
v->VisitPointer(&constant_pool_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);
DCHECK(*state->pc_address != NULL);
return EXIT;
}
Address ExitFrame::ComputeStackPointer(Address fp) {
return Memory::Address_at(fp + ExitFrameConstants::kSPOffset);
}
void ExitFrame::FillState(Address fp, Address sp, State* state) {
state->sp = sp;
state->fp = fp;
state->pc_address = ResolveReturnAddressLocation(
reinterpret_cast<Address*>(sp - 1 * kPCOnStackSize));
state->constant_pool_address =
reinterpret_cast<Address*>(fp + ExitFrameConstants::kConstantPoolOffset);
}
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();
DCHECK(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())));
state->constant_pool_address =
reinterpret_cast<Address*>(ComputeConstantPoolAddress(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 StandardFrame::IterateCompiledFrame(ObjectVisitor* v) const {
// Make sure that we're not doing "safe" stack frame iteration. We cannot
// possibly find pointers in optimized frames in that state.
DCHECK(can_access_heap_objects());
// 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()) {
// Number of doubles not known at snapshot time.
DCHECK(!isolate()->serializer_enabled());
parameters_base += DoubleRegister::NumAllocatableRegisters() *
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 return address in the callee and incoming arguments.
IteratePc(v, pc_address(), code);
// Visit the context in stub frame and JavaScript frame.
// Visit the function in JavaScript frame.
Object** fixed_base = &Memory::Object_at(
fp() + StandardFrameConstants::kMarkerOffset);
Object** fixed_limit = &Memory::Object_at(fp());
v->VisitPointers(fixed_base, fixed_limit);
}
void StubFrame::Iterate(ObjectVisitor* v) const {
IterateCompiledFrame(v);
}
Code* StubFrame::unchecked_code() const {
return static_cast<Code*>(isolate()->FindCodeObject(pc()));
}
Address StubFrame::GetCallerStackPointer() const {
return fp() + ExitFrameConstants::kCallerSPDisplacement;
}
int StubFrame::GetNumberOfIncomingArguments() const {
return 0;
}
void OptimizedFrame::Iterate(ObjectVisitor* v) const {
#ifdef DEBUG
// Make sure that optimized frames do not contain any stack handlers.
StackHandlerIterator it(this, top_handler());
DCHECK(it.done());
#endif
IterateCompiledFrame(v);
}
void JavaScriptFrame::SetParameterValue(int index, Object* value) const {
Memory::Object_at(GetParameterSlot(index)) = value;
}
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 {
return function()->code();
}
int JavaScriptFrame::GetNumberOfIncomingArguments() const {
DCHECK(can_access_heap_objects() &&
isolate()->heap()->gc_state() == Heap::NOT_IN_GC);
return function()->shared()->formal_parameter_count();
}
Address JavaScriptFrame::GetCallerStackPointer() const {
return fp() + StandardFrameConstants::kCallerSPOffset;
}
void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) {
DCHECK(functions->length() == 0);
functions->Add(function());
}
void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
DCHECK(functions->length() == 0);
Code* code_pointer = LookupCode();
int offset = static_cast<int>(pc() - code_pointer->address());
FrameSummary summary(receiver(),
function(),
code_pointer,
offset,
IsConstructor());
functions->Add(summary);
}
void JavaScriptFrame::PrintFunctionAndOffset(JSFunction* function, Code* code,
Address pc, FILE* file,
bool print_line_number) {
PrintF(file, "%s", function->IsOptimized() ? "*" : "~");
function->PrintName(file);
int code_offset = static_cast<int>(pc - code->instruction_start());
PrintF(file, "+%d", code_offset);
if (print_line_number) {
SharedFunctionInfo* shared = function->shared();
int source_pos = code->SourcePosition(pc);
Object* maybe_script = shared->script();
if (maybe_script->IsScript()) {
Script* script = Script::cast(maybe_script);
int line = script->GetLineNumber(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.get(), line);
} else {
PrintF(file, " at <unknown>:%d", line);
}
} else {
PrintF(file, " at <unknown>:<unknown>");
}
}
}
void JavaScriptFrame::PrintTop(Isolate* isolate, FILE* file, bool print_args,
bool print_line_number) {
// constructor calls
DisallowHeapAllocation no_allocation;
JavaScriptFrameIterator it(isolate);
while (!it.done()) {
if (it.frame()->is_java_script()) {
JavaScriptFrame* frame = it.frame();
if (frame->IsConstructor()) PrintF(file, "new ");
PrintFunctionAndOffset(frame->function(), frame->unchecked_code(),
frame->pc(), file, print_line_number);
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 JavaScriptFrame::SaveOperandStack(FixedArray* store,
int* stack_handler_index) const {
int operands_count = store->length();
DCHECK_LE(operands_count, ComputeOperandsCount());
// Visit the stack in LIFO order, saving operands and stack handlers into the
// array. The saved stack handlers store a link to the next stack handler,
// which will allow RestoreOperandStack to rewind the handlers.
StackHandlerIterator it(this, top_handler());
int i = operands_count - 1;
*stack_handler_index = -1;
for (; !it.done(); it.Advance()) {
StackHandler* handler = it.handler();
// Save operands pushed after the handler was pushed.
for (; GetOperandSlot(i) < handler->address(); i--) {
store->set(i, GetOperand(i));
}
DCHECK_GE(i + 1, StackHandlerConstants::kSlotCount);
DCHECK_EQ(handler->address(), GetOperandSlot(i));
int next_stack_handler_index = i + 1 - StackHandlerConstants::kSlotCount;
handler->Unwind(isolate(), store, next_stack_handler_index,
*stack_handler_index);
*stack_handler_index = next_stack_handler_index;
i -= StackHandlerConstants::kSlotCount;
}
// Save any remaining operands.
for (; i >= 0; i--) {
store->set(i, GetOperand(i));
}
}
void JavaScriptFrame::RestoreOperandStack(FixedArray* store,
int stack_handler_index) {
int operands_count = store->length();
DCHECK_LE(operands_count, ComputeOperandsCount());
int i = 0;
while (i <= stack_handler_index) {
if (i < stack_handler_index) {
// An operand.
DCHECK_EQ(GetOperand(i), isolate()->heap()->the_hole_value());
Memory::Object_at(GetOperandSlot(i)) = store->get(i);
i++;
} else {
// A stack handler.
DCHECK_EQ(i, stack_handler_index);
// The FixedArray store grows up. The stack grows down. So the operand
// slot for i actually points to the bottom of the top word in the
// handler. The base of the StackHandler* is the address of the bottom
// word, which will be the last slot that is in the handler.
int handler_slot_index = i + StackHandlerConstants::kSlotCount - 1;
StackHandler *handler =
StackHandler::FromAddress(GetOperandSlot(handler_slot_index));
stack_handler_index = handler->Rewind(isolate(), store, i, fp());
i += StackHandlerConstants::kSlotCount;
}
}
for (; i < operands_count; i++) {
DCHECK_EQ(GetOperand(i), isolate()->heap()->the_hole_value());
Memory::Object_at(GetOperandSlot(i)) = store->get(i);
}
}
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 function();
}
return JSFunction::cast(literal_array->get(literal_id));
}
void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
DCHECK(frames->length() == 0);
DCHECK(is_optimized());
// Delegate to JS frame in absence of turbofan deoptimization.
// TODO(turbofan): Revisit once we support deoptimization across the board.
if (LookupCode()->is_turbofanned() && !FLAG_turbo_deoptimization) {
return JavaScriptFrame::Summarize(frames);
}
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.
DCHECK(deopt_index != Safepoint::kNoDeoptimizationIndex);
TranslationIterator it(data->TranslationByteArray(),
data->TranslationIndex(deopt_index)->value());
Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
DCHECK(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--;
BailoutId ast_id = BailoutId(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.
// If we are at a call, the receiver is always in a stack slot.
// Otherwise we are not guaranteed to get the receiver value.
opcode = static_cast<Translation::Opcode>(it.Next());
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 if (opcode == Translation::STACK_SLOT) {
// 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);
}
} else {
// The receiver is not in a stack slot nor in a literal. We give up.
// TODO(3029): Materializing a captured object (or duplicated
// object) is hard, we return undefined for now. This breaks the
// produced stack trace, as constructor frames aren't marked as
// such anymore.
receiver = isolate()->heap()->undefined_value();
}
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;
DCHECK(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));
DCHECK(!is_constructor);
is_constructor = true;
} else {
// Skip over operands to advance to the next opcode.
it.Skip(Translation::NumberOfOperandsFor(opcode));
}
}
DCHECK(!is_constructor);
}
DeoptimizationInputData* OptimizedFrame::GetDeoptimizationData(
int* deopt_index) {
DCHECK(is_optimized());
JSFunction* opt_function = 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());
}
DCHECK(code != NULL);
DCHECK(code->kind() == Code::OPTIMIZED_FUNCTION);
SafepointEntry safepoint_entry = code->GetSafepointEntry(pc());
*deopt_index = safepoint_entry.deoptimization_index();
DCHECK(*deopt_index != Safepoint::kNoDeoptimizationIndex);
return DeoptimizationInputData::cast(code->deoptimization_data());
}
int OptimizedFrame::GetInlineCount() {
DCHECK(is_optimized());
// Delegate to JS frame in absence of turbofan deoptimization.
// TODO(turbofan): Revisit once we support deoptimization across the board.
if (LookupCode()->is_turbofanned() && !FLAG_turbo_deoptimization) {
return JavaScriptFrame::GetInlineCount();
}
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());
DCHECK(opcode == Translation::BEGIN);
USE(opcode);
it.Next(); // Drop frame count.
int jsframe_count = it.Next();
return jsframe_count;
}
void OptimizedFrame::GetFunctions(List<JSFunction*>* functions) {
DCHECK(functions->length() == 0);
DCHECK(is_optimized());
// Delegate to JS frame in absence of turbofan deoptimization.
// TODO(turbofan): Revisit once we support deoptimization across the board.
if (LookupCode()->is_turbofanned() && !FLAG_turbo_deoptimization) {
return JavaScriptFrame::GetFunctions(functions);
}
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());
DCHECK(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);
DCHECK(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 {
DisallowHeapAllocation no_gc;
Object* receiver = this->receiver();
JSFunction* 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.
SharedFunctionInfo* shared = function->shared();
ScopeInfo* scope_info = shared->scope_info();
Object* script_obj = shared->script();
if (script_obj->IsScript()) {
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 = script->GetLineNumber(source_pos) + 1;
accumulator->Add(":%d", line);
} else {
int function_start_pos = shared->start_position();
int line = script->GetLineNumber(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());
}
while (context->IsWithContext()) {
context = context->previous();
DCHECK(context != NULL);
}
// 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) {
int index = Context::MIN_CONTEXT_SLOTS + i;
if (index < context->length()) {
accumulator->Add("%o", context->get(index));
} 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) {
OStringStream os;
SharedFunctionInfo* shared = function->shared();
os << "--------- s o u r c e c o d e ---------\n"
<< SourceCodeOf(shared, FLAG_max_stack_trace_source_length)
<< "\n-----------------------------------------\n";
accumulator->Add(os.c_str());
}
accumulator->Add("}\n\n");
}
void ArgumentsAdaptorFrame::Print(StringStream* accumulator,
PrintMode mode,
int index) const {
int actual = ComputeParametersCount();
int expected = -1;
JSFunction* function = this->function();
expected = 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());
DCHECK(!it.done());
StackHandler* handler = it.handler();
DCHECK(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();
DCHECK(it.done());
#endif
IteratePc(v, pc_address(), LookupCode());
}
void StandardFrame::IterateExpressions(ObjectVisitor* v) const {
const int offset = StandardFrameConstants::kLastObjectOffset;
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());
}
void StubFailureTrampolineFrame::Iterate(ObjectVisitor* v) const {
Object** base = &Memory::Object_at(sp());
Object** limit = &Memory::Object_at(fp() +
kFirstRegisterParameterFrameOffset);
v->VisitPointers(base, limit);
base = &Memory::Object_at(fp() + StandardFrameConstants::kMarkerOffset);
const int offset = StandardFrameConstants::kLastObjectOffset;
limit = &Memory::Object_at(fp() + offset) + 1;
v->VisitPointers(base, limit);
IteratePc(v, pc_address(), LookupCode());
}
Address StubFailureTrampolineFrame::GetCallerStackPointer() const {
return fp() + StandardFrameConstants::kCallerSPOffset;
}
Code* StubFailureTrampolineFrame::unchecked_code() const {
Code* trampoline;
StubFailureTrampolineStub(isolate(), NOT_JS_FUNCTION_STUB_MODE).
FindCodeInCache(&trampoline);
if (trampoline->contains(pc())) {
return trampoline;
}
StubFailureTrampolineStub(isolate(), JS_FUNCTION_STUB_MODE).
FindCodeInCache(&trampoline);
if (trampoline->contains(pc())) {
return trampoline;
}
UNREACHABLE();
return NULL;
}
// -------------------------------------------------------------------------
JavaScriptFrame* StackFrameLocator::FindJavaScriptFrame(int n) {
DCHECK(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);
DCHECK(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);
DCHECK(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();
DCHECK(base::bits::IsPowerOfTwo32(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();
DCHECK(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;
}
// -------------------------------------------------------------------------
void StackHandler::Unwind(Isolate* isolate,
FixedArray* array,
int offset,
int previous_handler_offset) const {
STATIC_ASSERT(StackHandlerConstants::kSlotCount >= 5);
DCHECK_LE(0, offset);
DCHECK_GE(array->length(), offset + StackHandlerConstants::kSlotCount);
// Unwinding a stack handler into an array chains it in the opposite
// direction, re-using the "next" slot as a "previous" link, so that stack
// handlers can be later re-wound in the correct order. Decode the "state"
// slot into "index" and "kind" and store them separately, using the fp slot.
array->set(offset, Smi::FromInt(previous_handler_offset)); // next
array->set(offset + 1, *code_address()); // code
array->set(offset + 2, Smi::FromInt(static_cast<int>(index()))); // state
array->set(offset + 3, *context_address()); // context
array->set(offset + 4, Smi::FromInt(static_cast<int>(kind()))); // fp
*isolate->handler_address() = next()->address();
}
int StackHandler::Rewind(Isolate* isolate,
FixedArray* array,
int offset,
Address fp) {
STATIC_ASSERT(StackHandlerConstants::kSlotCount >= 5);
DCHECK_LE(0, offset);
DCHECK_GE(array->length(), offset + StackHandlerConstants::kSlotCount);
Smi* prev_handler_offset = Smi::cast(array->get(offset));
Code* code = Code::cast(array->get(offset + 1));
Smi* smi_index = Smi::cast(array->get(offset + 2));
Object* context = array->get(offset + 3);
Smi* smi_kind = Smi::cast(array->get(offset + 4));
unsigned state = KindField::encode(static_cast<Kind>(smi_kind->value())) |
IndexField::encode(static_cast<unsigned>(smi_index->value()));
Memory::Address_at(address() + StackHandlerConstants::kNextOffset) =
*isolate->handler_address();
Memory::Object_at(address() + StackHandlerConstants::kCodeOffset) = code;
Memory::uintptr_at(address() + StackHandlerConstants::kStateOffset) = state;
Memory::Object_at(address() + StackHandlerConstants::kContextOffset) =
context;
SetFp(address() + StackHandlerConstants::kFPOffset, fp);
*isolate->handler_address() = address();
return prev_handler_offset->value();
}
// -------------------------------------------------------------------------
int NumRegs(RegList reglist) { return base::bits::CountPopulation32(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;
DCHECK(i == kNumJSCallerSaved);
}
int JSCallerSavedCode(int n) {
DCHECK(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(Isolate* isolate, Zone* zone) {
ZoneList<StackFrame*> list(10, zone);
for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
list.Add(frame, zone);
}
return list.ToVector();
}
} } // namespace v8::internal