v8/src/deoptimizer.cc
fschneider@chromium.org 8480569467 Fix lazy deoptimization at HInvokeFunction and enable target-recording call-function stub.
Changes the way we do lazy deoptimization:

1. For side-effect instructions, we insert the lazy-deopt call at
the following LLazyBailout instruction.

     CALL
     GAP
     LAZY-BAILOUT ==> lazy-deopt-call

2. For other instructions (StackCheck) we insert it right after the
instruction since the deopt targets an earlier deoptimization environment.

   STACK-CHECK
   GAP ==> lazy-deopt-call

The pc of the lazy-deopt call that will be patched in is recorded in the
deoptimization input data. Each Lithium instruction can have 0..n safepoints.
All safepoints get the deoptimization index of the associated LAZY-BAILOUT
instruction. On lazy deoptimization we use the return-pc to find the safepoint.
The safepoint tells us the deoptimization index, which in turn finds us the
PC where to insert the lazy-deopt-call.

Additional changes:
 * RegExpLiteral marked it as having side-effects so that it 
   gets an explicitlazy-bailout instruction (instead of
   treating it specially like stack-checks)
 * Enable target recording CallFunctionStub to achieve
   more inlining on optimized code.

BUG=v8:1789
TEST=jslint and uglify run without crashing, mjsunit/compiler/regress-lazy-deopt.js
Review URL: http://codereview.chromium.org/8492004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10006 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2011-11-16 08:44:30 +00:00

1503 lines
50 KiB
C++

// Copyright 2011 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 "codegen.h"
#include "deoptimizer.h"
#include "disasm.h"
#include "full-codegen.h"
#include "global-handles.h"
#include "macro-assembler.h"
#include "prettyprinter.h"
namespace v8 {
namespace internal {
DeoptimizerData::DeoptimizerData() {
eager_deoptimization_entry_code_ = NULL;
lazy_deoptimization_entry_code_ = NULL;
current_ = NULL;
deoptimizing_code_list_ = NULL;
#ifdef ENABLE_DEBUGGER_SUPPORT
deoptimized_frame_info_ = NULL;
#endif
}
DeoptimizerData::~DeoptimizerData() {
if (eager_deoptimization_entry_code_ != NULL) {
Isolate::Current()->memory_allocator()->Free(
eager_deoptimization_entry_code_);
eager_deoptimization_entry_code_ = NULL;
}
if (lazy_deoptimization_entry_code_ != NULL) {
Isolate::Current()->memory_allocator()->Free(
lazy_deoptimization_entry_code_);
lazy_deoptimization_entry_code_ = NULL;
}
}
#ifdef ENABLE_DEBUGGER_SUPPORT
void DeoptimizerData::Iterate(ObjectVisitor* v) {
if (deoptimized_frame_info_ != NULL) {
deoptimized_frame_info_->Iterate(v);
}
}
#endif
// We rely on this function not causing a GC. It is called from generated code
// without having a real stack frame in place.
Deoptimizer* Deoptimizer::New(JSFunction* function,
BailoutType type,
unsigned bailout_id,
Address from,
int fp_to_sp_delta,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
Deoptimizer* deoptimizer = new Deoptimizer(isolate,
function,
type,
bailout_id,
from,
fp_to_sp_delta,
NULL);
ASSERT(isolate->deoptimizer_data()->current_ == NULL);
isolate->deoptimizer_data()->current_ = deoptimizer;
return deoptimizer;
}
Deoptimizer* Deoptimizer::Grab(Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
Deoptimizer* result = isolate->deoptimizer_data()->current_;
ASSERT(result != NULL);
result->DeleteFrameDescriptions();
isolate->deoptimizer_data()->current_ = NULL;
return result;
}
#ifdef ENABLE_DEBUGGER_SUPPORT
DeoptimizedFrameInfo* Deoptimizer::DebuggerInspectableFrame(
JavaScriptFrame* frame,
int frame_index,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
ASSERT(frame->is_optimized());
ASSERT(isolate->deoptimizer_data()->deoptimized_frame_info_ == NULL);
// Get the function and code from the frame.
JSFunction* function = JSFunction::cast(frame->function());
Code* code = frame->LookupCode();
// Locate the deoptimization point in the code. As we are at a call the
// return address must be at a place in the code with deoptimization support.
SafepointEntry safepoint_entry = code->GetSafepointEntry(frame->pc());
int deoptimization_index = safepoint_entry.deoptimization_index();
ASSERT(deoptimization_index != Safepoint::kNoDeoptimizationIndex);
// Always use the actual stack slots when calculating the fp to sp
// delta adding two for the function and context.
unsigned stack_slots = code->stack_slots();
unsigned fp_to_sp_delta = ((stack_slots + 2) * kPointerSize);
Deoptimizer* deoptimizer = new Deoptimizer(isolate,
function,
Deoptimizer::DEBUGGER,
deoptimization_index,
frame->pc(),
fp_to_sp_delta,
code);
Address tos = frame->fp() - fp_to_sp_delta;
deoptimizer->FillInputFrame(tos, frame);
// Calculate the output frames.
Deoptimizer::ComputeOutputFrames(deoptimizer);
// Create the GC safe output frame information and register it for GC
// handling.
ASSERT_LT(frame_index, deoptimizer->output_count());
DeoptimizedFrameInfo* info =
new DeoptimizedFrameInfo(deoptimizer, frame_index);
isolate->deoptimizer_data()->deoptimized_frame_info_ = info;
// Get the "simulated" top and size for the requested frame.
Address top =
reinterpret_cast<Address>(deoptimizer->output_[frame_index]->GetTop());
uint32_t size = deoptimizer->output_[frame_index]->GetFrameSize();
// Done with the GC-unsafe frame descriptions. This re-enables allocation.
deoptimizer->DeleteFrameDescriptions();
// Allocate a heap number for the doubles belonging to this frame.
deoptimizer->MaterializeHeapNumbersForDebuggerInspectableFrame(
top, size, info);
// Finished using the deoptimizer instance.
delete deoptimizer;
return info;
}
void Deoptimizer::DeleteDebuggerInspectableFrame(DeoptimizedFrameInfo* info,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
ASSERT(isolate->deoptimizer_data()->deoptimized_frame_info_ == info);
delete info;
isolate->deoptimizer_data()->deoptimized_frame_info_ = NULL;
}
#endif
void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
int count,
BailoutType type) {
TableEntryGenerator generator(masm, type, count);
generator.Generate();
}
class DeoptimizingVisitor : public OptimizedFunctionVisitor {
public:
virtual void EnterContext(Context* context) {
if (FLAG_trace_deopt) {
PrintF("[deoptimize context: %" V8PRIxPTR "]\n",
reinterpret_cast<intptr_t>(context));
}
}
virtual void VisitFunction(JSFunction* function) {
Deoptimizer::DeoptimizeFunction(function);
}
virtual void LeaveContext(Context* context) {
context->ClearOptimizedFunctions();
}
};
void Deoptimizer::DeoptimizeAll() {
AssertNoAllocation no_allocation;
if (FLAG_trace_deopt) {
PrintF("[deoptimize all contexts]\n");
}
DeoptimizingVisitor visitor;
VisitAllOptimizedFunctions(&visitor);
}
void Deoptimizer::DeoptimizeGlobalObject(JSObject* object) {
AssertNoAllocation no_allocation;
DeoptimizingVisitor visitor;
VisitAllOptimizedFunctionsForGlobalObject(object, &visitor);
}
void Deoptimizer::VisitAllOptimizedFunctionsForContext(
Context* context, OptimizedFunctionVisitor* visitor) {
AssertNoAllocation no_allocation;
ASSERT(context->IsGlobalContext());
visitor->EnterContext(context);
// Run through the list of optimized functions and deoptimize them.
Object* element = context->OptimizedFunctionsListHead();
while (!element->IsUndefined()) {
JSFunction* element_function = JSFunction::cast(element);
// Get the next link before deoptimizing as deoptimizing will clear the
// next link.
element = element_function->next_function_link();
visitor->VisitFunction(element_function);
}
visitor->LeaveContext(context);
}
void Deoptimizer::VisitAllOptimizedFunctionsForGlobalObject(
JSObject* object, OptimizedFunctionVisitor* visitor) {
AssertNoAllocation no_allocation;
if (object->IsJSGlobalProxy()) {
Object* proto = object->GetPrototype();
ASSERT(proto->IsJSGlobalObject());
VisitAllOptimizedFunctionsForContext(
GlobalObject::cast(proto)->global_context(), visitor);
} else if (object->IsGlobalObject()) {
VisitAllOptimizedFunctionsForContext(
GlobalObject::cast(object)->global_context(), visitor);
}
}
void Deoptimizer::VisitAllOptimizedFunctions(
OptimizedFunctionVisitor* visitor) {
AssertNoAllocation no_allocation;
// Run through the list of all global contexts and deoptimize.
Object* global = Isolate::Current()->heap()->global_contexts_list();
while (!global->IsUndefined()) {
VisitAllOptimizedFunctionsForGlobalObject(Context::cast(global)->global(),
visitor);
global = Context::cast(global)->get(Context::NEXT_CONTEXT_LINK);
}
}
void Deoptimizer::HandleWeakDeoptimizedCode(
v8::Persistent<v8::Value> obj, void* data) {
DeoptimizingCodeListNode* node =
reinterpret_cast<DeoptimizingCodeListNode*>(data);
RemoveDeoptimizingCode(*node->code());
#ifdef DEBUG
node = Isolate::Current()->deoptimizer_data()->deoptimizing_code_list_;
while (node != NULL) {
ASSERT(node != reinterpret_cast<DeoptimizingCodeListNode*>(data));
node = node->next();
}
#endif
}
void Deoptimizer::ComputeOutputFrames(Deoptimizer* deoptimizer) {
deoptimizer->DoComputeOutputFrames();
}
Deoptimizer::Deoptimizer(Isolate* isolate,
JSFunction* function,
BailoutType type,
unsigned bailout_id,
Address from,
int fp_to_sp_delta,
Code* optimized_code)
: isolate_(isolate),
function_(function),
bailout_id_(bailout_id),
bailout_type_(type),
from_(from),
fp_to_sp_delta_(fp_to_sp_delta),
input_(NULL),
output_count_(0),
output_(NULL),
frame_alignment_marker_(isolate->heap()->frame_alignment_marker()),
has_alignment_padding_(0),
deferred_heap_numbers_(0) {
if (FLAG_trace_deopt && type != OSR) {
if (type == DEBUGGER) {
PrintF("**** DEOPT FOR DEBUGGER: ");
} else {
PrintF("**** DEOPT: ");
}
function->PrintName();
PrintF(" at bailout #%u, address 0x%" V8PRIxPTR ", frame size %d\n",
bailout_id,
reinterpret_cast<intptr_t>(from),
fp_to_sp_delta - (2 * kPointerSize));
} else if (FLAG_trace_osr && type == OSR) {
PrintF("**** OSR: ");
function->PrintName();
PrintF(" at ast id #%u, address 0x%" V8PRIxPTR ", frame size %d\n",
bailout_id,
reinterpret_cast<intptr_t>(from),
fp_to_sp_delta - (2 * kPointerSize));
}
// Find the optimized code.
if (type == EAGER) {
ASSERT(from == NULL);
optimized_code_ = function_->code();
if (FLAG_trace_deopt && FLAG_code_comments) {
// Print instruction associated with this bailout.
const char* last_comment = NULL;
int mask = RelocInfo::ModeMask(RelocInfo::COMMENT)
| RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY);
for (RelocIterator it(optimized_code_, mask); !it.done(); it.next()) {
RelocInfo* info = it.rinfo();
if (info->rmode() == RelocInfo::COMMENT) {
last_comment = reinterpret_cast<const char*>(info->data());
}
if (info->rmode() == RelocInfo::RUNTIME_ENTRY) {
unsigned id = Deoptimizer::GetDeoptimizationId(
info->target_address(), Deoptimizer::EAGER);
if (id == bailout_id && last_comment != NULL) {
PrintF(" %s\n", last_comment);
break;
}
}
}
}
} else if (type == LAZY) {
optimized_code_ = FindDeoptimizingCodeFromAddress(from);
ASSERT(optimized_code_ != NULL);
} else if (type == OSR) {
// The function has already been optimized and we're transitioning
// from the unoptimized shared version to the optimized one in the
// function. The return address (from) points to unoptimized code.
optimized_code_ = function_->code();
ASSERT(optimized_code_->kind() == Code::OPTIMIZED_FUNCTION);
ASSERT(!optimized_code_->contains(from));
} else if (type == DEBUGGER) {
optimized_code_ = optimized_code;
ASSERT(optimized_code_->contains(from));
}
ASSERT(HEAP->allow_allocation(false));
unsigned size = ComputeInputFrameSize();
input_ = new(size) FrameDescription(size, function);
#ifdef DEBUG
input_->SetKind(Code::OPTIMIZED_FUNCTION);
#endif
}
Deoptimizer::~Deoptimizer() {
ASSERT(input_ == NULL && output_ == NULL);
}
void Deoptimizer::DeleteFrameDescriptions() {
delete input_;
for (int i = 0; i < output_count_; ++i) {
if (output_[i] != input_) delete output_[i];
}
delete[] output_;
input_ = NULL;
output_ = NULL;
ASSERT(!HEAP->allow_allocation(true));
}
Address Deoptimizer::GetDeoptimizationEntry(int id, BailoutType type) {
ASSERT(id >= 0);
if (id >= kNumberOfEntries) return NULL;
MemoryChunk* base = NULL;
DeoptimizerData* data = Isolate::Current()->deoptimizer_data();
if (type == EAGER) {
if (data->eager_deoptimization_entry_code_ == NULL) {
data->eager_deoptimization_entry_code_ = CreateCode(type);
}
base = data->eager_deoptimization_entry_code_;
} else {
if (data->lazy_deoptimization_entry_code_ == NULL) {
data->lazy_deoptimization_entry_code_ = CreateCode(type);
}
base = data->lazy_deoptimization_entry_code_;
}
return
static_cast<Address>(base->body()) + (id * table_entry_size_);
}
int Deoptimizer::GetDeoptimizationId(Address addr, BailoutType type) {
MemoryChunk* base = NULL;
DeoptimizerData* data = Isolate::Current()->deoptimizer_data();
if (type == EAGER) {
base = data->eager_deoptimization_entry_code_;
} else {
base = data->lazy_deoptimization_entry_code_;
}
if (base == NULL ||
addr < base->body() ||
addr >= base->body() +
(kNumberOfEntries * table_entry_size_)) {
return kNotDeoptimizationEntry;
}
ASSERT_EQ(0,
static_cast<int>(addr - base->body()) % table_entry_size_);
return static_cast<int>(addr - base->body()) / table_entry_size_;
}
int Deoptimizer::GetOutputInfo(DeoptimizationOutputData* data,
unsigned id,
SharedFunctionInfo* shared) {
// TODO(kasperl): For now, we do a simple linear search for the PC
// offset associated with the given node id. This should probably be
// changed to a binary search.
int length = data->DeoptPoints();
Smi* smi_id = Smi::FromInt(id);
for (int i = 0; i < length; i++) {
if (data->AstId(i) == smi_id) {
return data->PcAndState(i)->value();
}
}
PrintF("[couldn't find pc offset for node=%u]\n", id);
PrintF("[method: %s]\n", *shared->DebugName()->ToCString());
// Print the source code if available.
HeapStringAllocator string_allocator;
StringStream stream(&string_allocator);
shared->SourceCodePrint(&stream, -1);
PrintF("[source:\n%s\n]", *stream.ToCString());
UNREACHABLE();
return -1;
}
int Deoptimizer::GetDeoptimizedCodeCount(Isolate* isolate) {
int length = 0;
DeoptimizingCodeListNode* node =
isolate->deoptimizer_data()->deoptimizing_code_list_;
while (node != NULL) {
length++;
node = node->next();
}
return length;
}
// We rely on this function not causing a GC. It is called from generated code
// without having a real stack frame in place.
void Deoptimizer::DoComputeOutputFrames() {
if (bailout_type_ == OSR) {
DoComputeOsrOutputFrame();
return;
}
// Print some helpful diagnostic information.
int64_t start = OS::Ticks();
if (FLAG_trace_deopt) {
PrintF("[deoptimizing%s: begin 0x%08" V8PRIxPTR " ",
(bailout_type_ == LAZY ? " (lazy)" : ""),
reinterpret_cast<intptr_t>(function_));
function_->PrintName();
PrintF(" @%d]\n", bailout_id_);
}
// Determine basic deoptimization information. The optimized frame is
// described by the input data.
DeoptimizationInputData* input_data =
DeoptimizationInputData::cast(optimized_code_->deoptimization_data());
unsigned node_id = input_data->AstId(bailout_id_)->value();
ByteArray* translations = input_data->TranslationByteArray();
unsigned translation_index =
input_data->TranslationIndex(bailout_id_)->value();
// Do the input frame to output frame(s) translation.
TranslationIterator iterator(translations, translation_index);
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator.Next());
ASSERT(Translation::BEGIN == opcode);
USE(opcode);
// Read the number of output frames and allocate an array for their
// descriptions.
int count = iterator.Next();
ASSERT(output_ == NULL);
output_ = new FrameDescription*[count];
for (int i = 0; i < count; ++i) {
output_[i] = NULL;
}
output_count_ = count;
// Translate each output frame.
for (int i = 0; i < count; ++i) {
DoComputeFrame(&iterator, i);
}
// Print some helpful diagnostic information.
if (FLAG_trace_deopt) {
double ms = static_cast<double>(OS::Ticks() - start) / 1000;
int index = output_count_ - 1; // Index of the topmost frame.
JSFunction* function = output_[index]->GetFunction();
PrintF("[deoptimizing: end 0x%08" V8PRIxPTR " ",
reinterpret_cast<intptr_t>(function));
function->PrintName();
PrintF(" => node=%u, pc=0x%08" V8PRIxPTR ", state=%s, took %0.3f ms]\n",
node_id,
output_[index]->GetPc(),
FullCodeGenerator::State2String(
static_cast<FullCodeGenerator::State>(
output_[index]->GetState()->value())),
ms);
}
}
void Deoptimizer::MaterializeHeapNumbers() {
ASSERT_NE(DEBUGGER, bailout_type_);
for (int i = 0; i < deferred_heap_numbers_.length(); i++) {
HeapNumberMaterializationDescriptor d = deferred_heap_numbers_[i];
Handle<Object> num = isolate_->factory()->NewNumber(d.value());
if (FLAG_trace_deopt) {
PrintF("Materializing a new heap number %p [%e] in slot %p\n",
reinterpret_cast<void*>(*num),
d.value(),
d.slot_address());
}
Memory::Object_at(d.slot_address()) = *num;
}
}
#ifdef ENABLE_DEBUGGER_SUPPORT
void Deoptimizer::MaterializeHeapNumbersForDebuggerInspectableFrame(
Address top, uint32_t size, DeoptimizedFrameInfo* info) {
ASSERT_EQ(DEBUGGER, bailout_type_);
for (int i = 0; i < deferred_heap_numbers_.length(); i++) {
HeapNumberMaterializationDescriptor d = deferred_heap_numbers_[i];
// Check of the heap number to materialize actually belong to the frame
// being extracted.
Address slot = d.slot_address();
if (top <= slot && slot < top + size) {
Handle<Object> num = isolate_->factory()->NewNumber(d.value());
// Calculate the index with the botton of the expression stack
// at index 0, and the fixed part (including incoming arguments)
// at negative indexes.
int index = static_cast<int>(
info->expression_count_ - (slot - top) / kPointerSize - 1);
if (FLAG_trace_deopt) {
PrintF("Materializing a new heap number %p [%e] in slot %p"
"for stack index %d\n",
reinterpret_cast<void*>(*num),
d.value(),
d.slot_address(),
index);
}
if (index >=0) {
info->SetExpression(index, *num);
} else {
// Calculate parameter index subtracting one for the receiver.
int parameter_index =
index +
static_cast<int>(size) / kPointerSize -
info->expression_count_ - 1;
info->SetParameter(parameter_index, *num);
}
}
}
}
#endif
void Deoptimizer::DoTranslateCommand(TranslationIterator* iterator,
int frame_index,
unsigned output_offset) {
disasm::NameConverter converter;
// A GC-safe temporary placeholder that we can put in the output frame.
const intptr_t kPlaceholder = reinterpret_cast<intptr_t>(Smi::FromInt(0));
// Ignore commands marked as duplicate and act on the first non-duplicate.
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator->Next());
while (opcode == Translation::DUPLICATE) {
opcode = static_cast<Translation::Opcode>(iterator->Next());
iterator->Skip(Translation::NumberOfOperandsFor(opcode));
opcode = static_cast<Translation::Opcode>(iterator->Next());
}
switch (opcode) {
case Translation::BEGIN:
case Translation::FRAME:
case Translation::DUPLICATE:
UNREACHABLE();
return;
case Translation::REGISTER: {
int input_reg = iterator->Next();
intptr_t input_value = input_->GetRegister(input_reg);
if (FLAG_trace_deopt) {
PrintF(
" 0x%08" V8PRIxPTR ": [top + %d] <- 0x%08" V8PRIxPTR " ; %s ",
output_[frame_index]->GetTop() + output_offset,
output_offset,
input_value,
converter.NameOfCPURegister(input_reg));
reinterpret_cast<Object*>(input_value)->ShortPrint();
PrintF("\n");
}
output_[frame_index]->SetFrameSlot(output_offset, input_value);
return;
}
case Translation::INT32_REGISTER: {
int input_reg = iterator->Next();
intptr_t value = input_->GetRegister(input_reg);
bool is_smi = Smi::IsValid(value);
if (FLAG_trace_deopt) {
PrintF(
" 0x%08" V8PRIxPTR ": [top + %d] <- %" V8PRIdPTR " ; %s (%s)\n",
output_[frame_index]->GetTop() + output_offset,
output_offset,
value,
converter.NameOfCPURegister(input_reg),
is_smi ? "smi" : "heap number");
}
if (is_smi) {
intptr_t tagged_value =
reinterpret_cast<intptr_t>(Smi::FromInt(static_cast<int>(value)));
output_[frame_index]->SetFrameSlot(output_offset, tagged_value);
} else {
// We save the untagged value on the side and store a GC-safe
// temporary placeholder in the frame.
AddDoubleValue(output_[frame_index]->GetTop() + output_offset,
static_cast<double>(static_cast<int32_t>(value)));
output_[frame_index]->SetFrameSlot(output_offset, kPlaceholder);
}
return;
}
case Translation::DOUBLE_REGISTER: {
int input_reg = iterator->Next();
double value = input_->GetDoubleRegister(input_reg);
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": [top + %d] <- %e ; %s\n",
output_[frame_index]->GetTop() + output_offset,
output_offset,
value,
DoubleRegister::AllocationIndexToString(input_reg));
}
// We save the untagged value on the side and store a GC-safe
// temporary placeholder in the frame.
AddDoubleValue(output_[frame_index]->GetTop() + output_offset, value);
output_[frame_index]->SetFrameSlot(output_offset, kPlaceholder);
return;
}
case Translation::STACK_SLOT: {
int input_slot_index = iterator->Next();
unsigned input_offset =
input_->GetOffsetFromSlotIndex(this, input_slot_index);
intptr_t input_value = input_->GetFrameSlot(input_offset);
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": ",
output_[frame_index]->GetTop() + output_offset);
PrintF("[top + %d] <- 0x%08" V8PRIxPTR " ; [esp + %d] ",
output_offset,
input_value,
input_offset);
reinterpret_cast<Object*>(input_value)->ShortPrint();
PrintF("\n");
}
output_[frame_index]->SetFrameSlot(output_offset, input_value);
return;
}
case Translation::INT32_STACK_SLOT: {
int input_slot_index = iterator->Next();
unsigned input_offset =
input_->GetOffsetFromSlotIndex(this, input_slot_index);
intptr_t value = input_->GetFrameSlot(input_offset);
bool is_smi = Smi::IsValid(value);
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": ",
output_[frame_index]->GetTop() + output_offset);
PrintF("[top + %d] <- %" V8PRIdPTR " ; [esp + %d] (%s)\n",
output_offset,
value,
input_offset,
is_smi ? "smi" : "heap number");
}
if (is_smi) {
intptr_t tagged_value =
reinterpret_cast<intptr_t>(Smi::FromInt(static_cast<int>(value)));
output_[frame_index]->SetFrameSlot(output_offset, tagged_value);
} else {
// We save the untagged value on the side and store a GC-safe
// temporary placeholder in the frame.
AddDoubleValue(output_[frame_index]->GetTop() + output_offset,
static_cast<double>(static_cast<int32_t>(value)));
output_[frame_index]->SetFrameSlot(output_offset, kPlaceholder);
}
return;
}
case Translation::DOUBLE_STACK_SLOT: {
int input_slot_index = iterator->Next();
unsigned input_offset =
input_->GetOffsetFromSlotIndex(this, input_slot_index);
double value = input_->GetDoubleFrameSlot(input_offset);
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": [top + %d] <- %e ; [esp + %d]\n",
output_[frame_index]->GetTop() + output_offset,
output_offset,
value,
input_offset);
}
// We save the untagged value on the side and store a GC-safe
// temporary placeholder in the frame.
AddDoubleValue(output_[frame_index]->GetTop() + output_offset, value);
output_[frame_index]->SetFrameSlot(output_offset, kPlaceholder);
return;
}
case Translation::LITERAL: {
Object* literal = ComputeLiteral(iterator->Next());
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": [top + %d] <- ",
output_[frame_index]->GetTop() + output_offset,
output_offset);
literal->ShortPrint();
PrintF(" ; literal\n");
}
intptr_t value = reinterpret_cast<intptr_t>(literal);
output_[frame_index]->SetFrameSlot(output_offset, value);
return;
}
case Translation::ARGUMENTS_OBJECT: {
// Use the arguments marker value as a sentinel and fill in the arguments
// object after the deoptimized frame is built.
ASSERT(frame_index == 0); // Only supported for first frame.
if (FLAG_trace_deopt) {
PrintF(" 0x%08" V8PRIxPTR ": [top + %d] <- ",
output_[frame_index]->GetTop() + output_offset,
output_offset);
isolate_->heap()->arguments_marker()->ShortPrint();
PrintF(" ; arguments object\n");
}
intptr_t value = reinterpret_cast<intptr_t>(
isolate_->heap()->arguments_marker());
output_[frame_index]->SetFrameSlot(output_offset, value);
return;
}
}
}
bool Deoptimizer::DoOsrTranslateCommand(TranslationIterator* iterator,
int* input_offset) {
disasm::NameConverter converter;
FrameDescription* output = output_[0];
// The input values are all part of the unoptimized frame so they
// are all tagged pointers.
uintptr_t input_value = input_->GetFrameSlot(*input_offset);
Object* input_object = reinterpret_cast<Object*>(input_value);
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator->Next());
bool duplicate = (opcode == Translation::DUPLICATE);
if (duplicate) {
opcode = static_cast<Translation::Opcode>(iterator->Next());
}
switch (opcode) {
case Translation::BEGIN:
case Translation::FRAME:
case Translation::DUPLICATE:
UNREACHABLE(); // Malformed input.
return false;
case Translation::REGISTER: {
int output_reg = iterator->Next();
if (FLAG_trace_osr) {
PrintF(" %s <- 0x%08" V8PRIxPTR " ; [sp + %d]\n",
converter.NameOfCPURegister(output_reg),
input_value,
*input_offset);
}
output->SetRegister(output_reg, input_value);
break;
}
case Translation::INT32_REGISTER: {
// Abort OSR if we don't have a number.
if (!input_object->IsNumber()) return false;
int output_reg = iterator->Next();
int int32_value = input_object->IsSmi()
? Smi::cast(input_object)->value()
: FastD2I(input_object->Number());
// Abort the translation if the conversion lost information.
if (!input_object->IsSmi() &&
FastI2D(int32_value) != input_object->Number()) {
if (FLAG_trace_osr) {
PrintF("**** %g could not be converted to int32 ****\n",
input_object->Number());
}
return false;
}
if (FLAG_trace_osr) {
PrintF(" %s <- %d (int32) ; [sp + %d]\n",
converter.NameOfCPURegister(output_reg),
int32_value,
*input_offset);
}
output->SetRegister(output_reg, int32_value);
break;
}
case Translation::DOUBLE_REGISTER: {
// Abort OSR if we don't have a number.
if (!input_object->IsNumber()) return false;
int output_reg = iterator->Next();
double double_value = input_object->Number();
if (FLAG_trace_osr) {
PrintF(" %s <- %g (double) ; [sp + %d]\n",
DoubleRegister::AllocationIndexToString(output_reg),
double_value,
*input_offset);
}
output->SetDoubleRegister(output_reg, double_value);
break;
}
case Translation::STACK_SLOT: {
int output_index = iterator->Next();
unsigned output_offset =
output->GetOffsetFromSlotIndex(this, output_index);
if (FLAG_trace_osr) {
PrintF(" [sp + %d] <- 0x%08" V8PRIxPTR " ; [sp + %d] ",
output_offset,
input_value,
*input_offset);
reinterpret_cast<Object*>(input_value)->ShortPrint();
PrintF("\n");
}
output->SetFrameSlot(output_offset, input_value);
break;
}
case Translation::INT32_STACK_SLOT: {
// Abort OSR if we don't have a number.
if (!input_object->IsNumber()) return false;
int output_index = iterator->Next();
unsigned output_offset =
output->GetOffsetFromSlotIndex(this, output_index);
int int32_value = input_object->IsSmi()
? Smi::cast(input_object)->value()
: DoubleToInt32(input_object->Number());
// Abort the translation if the conversion lost information.
if (!input_object->IsSmi() &&
FastI2D(int32_value) != input_object->Number()) {
if (FLAG_trace_osr) {
PrintF("**** %g could not be converted to int32 ****\n",
input_object->Number());
}
return false;
}
if (FLAG_trace_osr) {
PrintF(" [sp + %d] <- %d (int32) ; [sp + %d]\n",
output_offset,
int32_value,
*input_offset);
}
output->SetFrameSlot(output_offset, int32_value);
break;
}
case Translation::DOUBLE_STACK_SLOT: {
static const int kLowerOffset = 0 * kPointerSize;
static const int kUpperOffset = 1 * kPointerSize;
// Abort OSR if we don't have a number.
if (!input_object->IsNumber()) return false;
int output_index = iterator->Next();
unsigned output_offset =
output->GetOffsetFromSlotIndex(this, output_index);
double double_value = input_object->Number();
uint64_t int_value = BitCast<uint64_t, double>(double_value);
int32_t lower = static_cast<int32_t>(int_value);
int32_t upper = static_cast<int32_t>(int_value >> kBitsPerInt);
if (FLAG_trace_osr) {
PrintF(" [sp + %d] <- 0x%08x (upper bits of %g) ; [sp + %d]\n",
output_offset + kUpperOffset,
upper,
double_value,
*input_offset);
PrintF(" [sp + %d] <- 0x%08x (lower bits of %g) ; [sp + %d]\n",
output_offset + kLowerOffset,
lower,
double_value,
*input_offset);
}
output->SetFrameSlot(output_offset + kLowerOffset, lower);
output->SetFrameSlot(output_offset + kUpperOffset, upper);
break;
}
case Translation::LITERAL: {
// Just ignore non-materialized literals.
iterator->Next();
break;
}
case Translation::ARGUMENTS_OBJECT: {
// Optimized code assumes that the argument object has not been
// materialized and so bypasses it when doing arguments access.
// We should have bailed out before starting the frame
// translation.
UNREACHABLE();
return false;
}
}
if (!duplicate) *input_offset -= kPointerSize;
return true;
}
void Deoptimizer::PatchStackCheckCode(Code* unoptimized_code,
Code* check_code,
Code* replacement_code) {
// Iterate over the stack check table and patch every stack check
// call to an unconditional call to the replacement code.
ASSERT(unoptimized_code->kind() == Code::FUNCTION);
Address stack_check_cursor = unoptimized_code->instruction_start() +
unoptimized_code->stack_check_table_offset();
uint32_t table_length = Memory::uint32_at(stack_check_cursor);
stack_check_cursor += kIntSize;
for (uint32_t i = 0; i < table_length; ++i) {
uint32_t pc_offset = Memory::uint32_at(stack_check_cursor + kIntSize);
Address pc_after = unoptimized_code->instruction_start() + pc_offset;
PatchStackCheckCodeAt(unoptimized_code,
pc_after,
check_code,
replacement_code);
stack_check_cursor += 2 * kIntSize;
}
}
void Deoptimizer::RevertStackCheckCode(Code* unoptimized_code,
Code* check_code,
Code* replacement_code) {
// Iterate over the stack check table and revert the patched
// stack check calls.
ASSERT(unoptimized_code->kind() == Code::FUNCTION);
Address stack_check_cursor = unoptimized_code->instruction_start() +
unoptimized_code->stack_check_table_offset();
uint32_t table_length = Memory::uint32_at(stack_check_cursor);
stack_check_cursor += kIntSize;
for (uint32_t i = 0; i < table_length; ++i) {
uint32_t pc_offset = Memory::uint32_at(stack_check_cursor + kIntSize);
Address pc_after = unoptimized_code->instruction_start() + pc_offset;
RevertStackCheckCodeAt(unoptimized_code,
pc_after,
check_code,
replacement_code);
stack_check_cursor += 2 * kIntSize;
}
}
unsigned Deoptimizer::ComputeInputFrameSize() const {
unsigned fixed_size = ComputeFixedSize(function_);
// The fp-to-sp delta already takes the context and the function
// into account so we have to avoid double counting them (-2).
unsigned result = fixed_size + fp_to_sp_delta_ - (2 * kPointerSize);
#ifdef DEBUG
if (bailout_type_ == OSR) {
// TODO(kasperl): It would be nice if we could verify that the
// size matches with the stack height we can compute based on the
// environment at the OSR entry. The code for that his built into
// the DoComputeOsrOutputFrame function for now.
} else {
unsigned stack_slots = optimized_code_->stack_slots();
unsigned outgoing_size = ComputeOutgoingArgumentSize();
ASSERT(result == fixed_size + (stack_slots * kPointerSize) + outgoing_size);
}
#endif
return result;
}
unsigned Deoptimizer::ComputeFixedSize(JSFunction* function) const {
// The fixed part of the frame consists of the return address, frame
// pointer, function, context, and all the incoming arguments.
static const unsigned kFixedSlotSize = 4 * kPointerSize;
return ComputeIncomingArgumentSize(function) + kFixedSlotSize;
}
unsigned Deoptimizer::ComputeIncomingArgumentSize(JSFunction* function) const {
// The incoming arguments is the values for formal parameters and
// the receiver. Every slot contains a pointer.
unsigned arguments = function->shared()->formal_parameter_count() + 1;
return arguments * kPointerSize;
}
unsigned Deoptimizer::ComputeOutgoingArgumentSize() const {
DeoptimizationInputData* data = DeoptimizationInputData::cast(
optimized_code_->deoptimization_data());
unsigned height = data->ArgumentsStackHeight(bailout_id_)->value();
return height * kPointerSize;
}
Object* Deoptimizer::ComputeLiteral(int index) const {
DeoptimizationInputData* data = DeoptimizationInputData::cast(
optimized_code_->deoptimization_data());
FixedArray* literals = data->LiteralArray();
return literals->get(index);
}
void Deoptimizer::AddDoubleValue(intptr_t slot_address,
double value) {
HeapNumberMaterializationDescriptor value_desc(
reinterpret_cast<Address>(slot_address), value);
deferred_heap_numbers_.Add(value_desc);
}
MemoryChunk* Deoptimizer::CreateCode(BailoutType type) {
// We cannot run this if the serializer is enabled because this will
// cause us to emit relocation information for the external
// references. This is fine because the deoptimizer's code section
// isn't meant to be serialized at all.
ASSERT(!Serializer::enabled());
MacroAssembler masm(Isolate::Current(), NULL, 16 * KB);
masm.set_emit_debug_code(false);
GenerateDeoptimizationEntries(&masm, kNumberOfEntries, type);
CodeDesc desc;
masm.GetCode(&desc);
ASSERT(desc.reloc_size == 0);
MemoryChunk* chunk =
Isolate::Current()->memory_allocator()->AllocateChunk(desc.instr_size,
EXECUTABLE,
NULL);
if (chunk == NULL) {
V8::FatalProcessOutOfMemory("Not enough memory for deoptimization table");
}
memcpy(chunk->body(), desc.buffer, desc.instr_size);
CPU::FlushICache(chunk->body(), desc.instr_size);
return chunk;
}
Code* Deoptimizer::FindDeoptimizingCodeFromAddress(Address addr) {
DeoptimizingCodeListNode* node =
Isolate::Current()->deoptimizer_data()->deoptimizing_code_list_;
while (node != NULL) {
if (node->code()->contains(addr)) return *node->code();
node = node->next();
}
return NULL;
}
void Deoptimizer::RemoveDeoptimizingCode(Code* code) {
DeoptimizerData* data = Isolate::Current()->deoptimizer_data();
ASSERT(data->deoptimizing_code_list_ != NULL);
// Run through the code objects to find this one and remove it.
DeoptimizingCodeListNode* prev = NULL;
DeoptimizingCodeListNode* current = data->deoptimizing_code_list_;
while (current != NULL) {
if (*current->code() == code) {
// Unlink from list. If prev is NULL we are looking at the first element.
if (prev == NULL) {
data->deoptimizing_code_list_ = current->next();
} else {
prev->set_next(current->next());
}
delete current;
return;
}
// Move to next in list.
prev = current;
current = current->next();
}
// Deoptimizing code is removed through weak callback. Each object is expected
// to be removed once and only once.
UNREACHABLE();
}
FrameDescription::FrameDescription(uint32_t frame_size,
JSFunction* function)
: frame_size_(frame_size),
function_(function),
top_(kZapUint32),
pc_(kZapUint32),
fp_(kZapUint32) {
// Zap all the registers.
for (int r = 0; r < Register::kNumRegisters; r++) {
SetRegister(r, kZapUint32);
}
// Zap all the slots.
for (unsigned o = 0; o < frame_size; o += kPointerSize) {
SetFrameSlot(o, kZapUint32);
}
}
unsigned FrameDescription::GetOffsetFromSlotIndex(Deoptimizer* deoptimizer,
int slot_index) {
if (slot_index >= 0) {
// Local or spill slots. Skip the fixed part of the frame
// including all arguments.
unsigned base =
GetFrameSize() - deoptimizer->ComputeFixedSize(GetFunction());
return base - ((slot_index + 1) * kPointerSize);
} else {
// Incoming parameter.
unsigned base = GetFrameSize() -
deoptimizer->ComputeIncomingArgumentSize(GetFunction());
return base - ((slot_index + 1) * kPointerSize);
}
}
int FrameDescription::ComputeParametersCount() {
return function_->shared()->formal_parameter_count();
}
Object* FrameDescription::GetParameter(Deoptimizer* deoptimizer, int index) {
ASSERT_EQ(Code::FUNCTION, kind_);
ASSERT(index >= 0);
ASSERT(index < ComputeParametersCount());
// The slot indexes for incoming arguments are negative.
unsigned offset = GetOffsetFromSlotIndex(deoptimizer,
index - ComputeParametersCount());
return reinterpret_cast<Object*>(*GetFrameSlotPointer(offset));
}
unsigned FrameDescription::GetExpressionCount(Deoptimizer* deoptimizer) {
ASSERT_EQ(Code::FUNCTION, kind_);
unsigned size = GetFrameSize() - deoptimizer->ComputeFixedSize(GetFunction());
return size / kPointerSize;
}
Object* FrameDescription::GetExpression(Deoptimizer* deoptimizer, int index) {
ASSERT_EQ(Code::FUNCTION, kind_);
unsigned offset = GetOffsetFromSlotIndex(deoptimizer, index);
return reinterpret_cast<Object*>(*GetFrameSlotPointer(offset));
}
void TranslationBuffer::Add(int32_t value) {
// Encode the sign bit in the least significant bit.
bool is_negative = (value < 0);
uint32_t bits = ((is_negative ? -value : value) << 1) |
static_cast<int32_t>(is_negative);
// Encode the individual bytes using the least significant bit of
// each byte to indicate whether or not more bytes follow.
do {
uint32_t next = bits >> 7;
contents_.Add(((bits << 1) & 0xFF) | (next != 0));
bits = next;
} while (bits != 0);
}
int32_t TranslationIterator::Next() {
// Run through the bytes until we reach one with a least significant
// bit of zero (marks the end).
uint32_t bits = 0;
for (int i = 0; true; i += 7) {
ASSERT(HasNext());
uint8_t next = buffer_->get(index_++);
bits |= (next >> 1) << i;
if ((next & 1) == 0) break;
}
// The bits encode the sign in the least significant bit.
bool is_negative = (bits & 1) == 1;
int32_t result = bits >> 1;
return is_negative ? -result : result;
}
Handle<ByteArray> TranslationBuffer::CreateByteArray() {
int length = contents_.length();
Handle<ByteArray> result =
Isolate::Current()->factory()->NewByteArray(length, TENURED);
memcpy(result->GetDataStartAddress(), contents_.ToVector().start(), length);
return result;
}
void Translation::BeginFrame(int node_id, int literal_id, unsigned height) {
buffer_->Add(FRAME);
buffer_->Add(node_id);
buffer_->Add(literal_id);
buffer_->Add(height);
}
void Translation::StoreRegister(Register reg) {
buffer_->Add(REGISTER);
buffer_->Add(reg.code());
}
void Translation::StoreInt32Register(Register reg) {
buffer_->Add(INT32_REGISTER);
buffer_->Add(reg.code());
}
void Translation::StoreDoubleRegister(DoubleRegister reg) {
buffer_->Add(DOUBLE_REGISTER);
buffer_->Add(DoubleRegister::ToAllocationIndex(reg));
}
void Translation::StoreStackSlot(int index) {
buffer_->Add(STACK_SLOT);
buffer_->Add(index);
}
void Translation::StoreInt32StackSlot(int index) {
buffer_->Add(INT32_STACK_SLOT);
buffer_->Add(index);
}
void Translation::StoreDoubleStackSlot(int index) {
buffer_->Add(DOUBLE_STACK_SLOT);
buffer_->Add(index);
}
void Translation::StoreLiteral(int literal_id) {
buffer_->Add(LITERAL);
buffer_->Add(literal_id);
}
void Translation::StoreArgumentsObject() {
buffer_->Add(ARGUMENTS_OBJECT);
}
void Translation::MarkDuplicate() {
buffer_->Add(DUPLICATE);
}
int Translation::NumberOfOperandsFor(Opcode opcode) {
switch (opcode) {
case ARGUMENTS_OBJECT:
case DUPLICATE:
return 0;
case BEGIN:
case REGISTER:
case INT32_REGISTER:
case DOUBLE_REGISTER:
case STACK_SLOT:
case INT32_STACK_SLOT:
case DOUBLE_STACK_SLOT:
case LITERAL:
return 1;
case FRAME:
return 3;
}
UNREACHABLE();
return -1;
}
#if defined(OBJECT_PRINT) || defined(ENABLE_DISASSEMBLER)
const char* Translation::StringFor(Opcode opcode) {
switch (opcode) {
case BEGIN:
return "BEGIN";
case FRAME:
return "FRAME";
case REGISTER:
return "REGISTER";
case INT32_REGISTER:
return "INT32_REGISTER";
case DOUBLE_REGISTER:
return "DOUBLE_REGISTER";
case STACK_SLOT:
return "STACK_SLOT";
case INT32_STACK_SLOT:
return "INT32_STACK_SLOT";
case DOUBLE_STACK_SLOT:
return "DOUBLE_STACK_SLOT";
case LITERAL:
return "LITERAL";
case ARGUMENTS_OBJECT:
return "ARGUMENTS_OBJECT";
case DUPLICATE:
return "DUPLICATE";
}
UNREACHABLE();
return "";
}
#endif
DeoptimizingCodeListNode::DeoptimizingCodeListNode(Code* code): next_(NULL) {
GlobalHandles* global_handles = Isolate::Current()->global_handles();
// Globalize the code object and make it weak.
code_ = Handle<Code>::cast(global_handles->Create(code));
global_handles->MakeWeak(reinterpret_cast<Object**>(code_.location()),
this,
Deoptimizer::HandleWeakDeoptimizedCode);
}
DeoptimizingCodeListNode::~DeoptimizingCodeListNode() {
GlobalHandles* global_handles = Isolate::Current()->global_handles();
global_handles->Destroy(reinterpret_cast<Object**>(code_.location()));
}
// We can't intermix stack decoding and allocations because
// deoptimization infrastracture is not GC safe.
// Thus we build a temporary structure in malloced space.
SlotRef SlotRef::ComputeSlotForNextArgument(TranslationIterator* iterator,
DeoptimizationInputData* data,
JavaScriptFrame* frame) {
Translation::Opcode opcode =
static_cast<Translation::Opcode>(iterator->Next());
switch (opcode) {
case Translation::BEGIN:
case Translation::FRAME:
// Peeled off before getting here.
break;
case Translation::ARGUMENTS_OBJECT:
// This can be only emitted for local slots not for argument slots.
break;
case Translation::REGISTER:
case Translation::INT32_REGISTER:
case Translation::DOUBLE_REGISTER:
case Translation::DUPLICATE:
// We are at safepoint which corresponds to call. All registers are
// saved by caller so there would be no live registers at this
// point. Thus these translation commands should not be used.
break;
case Translation::STACK_SLOT: {
int slot_index = iterator->Next();
Address slot_addr = SlotAddress(frame, slot_index);
return SlotRef(slot_addr, SlotRef::TAGGED);
}
case Translation::INT32_STACK_SLOT: {
int slot_index = iterator->Next();
Address slot_addr = SlotAddress(frame, slot_index);
return SlotRef(slot_addr, SlotRef::INT32);
}
case Translation::DOUBLE_STACK_SLOT: {
int slot_index = iterator->Next();
Address slot_addr = SlotAddress(frame, slot_index);
return SlotRef(slot_addr, SlotRef::DOUBLE);
}
case Translation::LITERAL: {
int literal_index = iterator->Next();
return SlotRef(data->LiteralArray()->get(literal_index));
}
}
UNREACHABLE();
return SlotRef();
}
void SlotRef::ComputeSlotMappingForArguments(JavaScriptFrame* frame,
int inlined_frame_index,
Vector<SlotRef>* args_slots) {
AssertNoAllocation no_gc;
int deopt_index = AstNode::kNoNumber;
DeoptimizationInputData* data =
static_cast<OptimizedFrame*>(frame)->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);
int frame_count = it.Next();
USE(frame_count);
ASSERT(frame_count > inlined_frame_index);
int frames_to_skip = inlined_frame_index;
while (true) {
opcode = static_cast<Translation::Opcode>(it.Next());
// Skip over operands to advance to the next opcode.
it.Skip(Translation::NumberOfOperandsFor(opcode));
if (opcode == Translation::FRAME) {
if (frames_to_skip == 0) {
// We reached the frame corresponding to the inlined function
// in question. Process the translation commands for the
// arguments.
//
// Skip the translation command for the receiver.
it.Skip(Translation::NumberOfOperandsFor(
static_cast<Translation::Opcode>(it.Next())));
// Compute slots for arguments.
for (int i = 0; i < args_slots->length(); ++i) {
(*args_slots)[i] = ComputeSlotForNextArgument(&it, data, frame);
}
return;
}
frames_to_skip--;
}
}
UNREACHABLE();
}
#ifdef ENABLE_DEBUGGER_SUPPORT
DeoptimizedFrameInfo::DeoptimizedFrameInfo(
Deoptimizer* deoptimizer, int frame_index) {
FrameDescription* output_frame = deoptimizer->output_[frame_index];
SetFunction(output_frame->GetFunction());
expression_count_ = output_frame->GetExpressionCount(deoptimizer);
parameters_count_ = output_frame->ComputeParametersCount();
parameters_ = new Object*[parameters_count_];
for (int i = 0; i < parameters_count_; i++) {
SetParameter(i, output_frame->GetParameter(deoptimizer, i));
}
expression_stack_ = new Object*[expression_count_];
for (int i = 0; i < expression_count_; i++) {
SetExpression(i, output_frame->GetExpression(deoptimizer, i));
}
}
DeoptimizedFrameInfo::~DeoptimizedFrameInfo() {
delete[] expression_stack_;
delete[] parameters_;
}
void DeoptimizedFrameInfo::Iterate(ObjectVisitor* v) {
v->VisitPointer(BitCast<Object**>(&function_));
v->VisitPointers(parameters_, parameters_ + parameters_count_);
v->VisitPointers(expression_stack_, expression_stack_ + expression_count_);
}
#endif // ENABLE_DEBUGGER_SUPPORT
} } // namespace v8::internal