Simplify isolates access during stack iteration (WAS: Move SafeStackFrameIterator::active_count_...)

src/frames.cc

 // Copyright 2006-2008 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
@@ skipping 21 matching lines @@
 #include "frames-inl.h"
 #include "full-codegen.h"
 #include "mark-compact.h"
 #include "safepoint-table.h"
 #include "scopeinfo.h"
 #include "string-stream.h"
 
 namespace v8 {
 namespace internal {
 
-
-int SafeStackFrameIterator::active_count_ = 0;
-
 // Iterator that supports traversing the stack handlers of a
 // particular frame. Needs to know the top of the handler chain.
 class StackHandlerIterator BASE_EMBEDDED {
  public:
   StackHandlerIterator(const StackFrame* frame, StackHandler* handler)
       : limit_(frame->fp()), handler_(handler) {
     // Make sure the handler has already been unwound to this frame.
     ASSERT(frame->sp() <= handler->address());
   }
 
@@ skipping 13 matching lines @@
 };
 
 
 // -------------------------------------------------------------------------
 
 
 #define INITIALIZE_SINGLETON(type, field) field##_(this),
 StackFrameIterator::StackFrameIterator()
     : STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
       frame_(NULL), handler_(NULL),
-      thread_(Isolate::Current()->thread_local_top()),
+      isolate_(Isolate::Current()),
+      thread_(isolate_->thread_local_top()),
       fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
   Reset();
 }
-StackFrameIterator::StackFrameIterator(ThreadLocalTop* t)
+StackFrameIterator::StackFrameIterator(Isolate* isolate)
     : STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
-      frame_(NULL), handler_(NULL), thread_(t),
+      frame_(NULL), handler_(NULL),
+      isolate_(isolate), thread_(isolate_->thread_local_top()),
       fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
   Reset();
 }
+StackFrameIterator::StackFrameIterator(Isolate* isolate, ThreadLocalTop* t)
+    : STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
+      frame_(NULL), handler_(NULL), isolate_(isolate), thread_(t),
+      fp_(NULL), sp_(NULL), advance_(&StackFrameIterator::AdvanceWithHandler) {
+  Reset();
+}
 StackFrameIterator::StackFrameIterator(Isolate* isolate,
                                        bool use_top, Address fp, Address sp)
     : STACK_FRAME_TYPE_LIST(INITIALIZE_SINGLETON)
       frame_(NULL), handler_(NULL),
-      thread_(use_top ? isolate->thread_local_top() : NULL),
+      isolate_(isolate),
+      thread_(use_top ? isolate_->thread_local_top() : NULL),
       fp_(use_top ? NULL : fp), sp_(sp),
       advance_(use_top ? &StackFrameIterator::AdvanceWithHandler :
                &StackFrameIterator::AdvanceWithoutHandler) {
   if (use_top || fp != NULL) {
     Reset();
   }
 }
 
 #undef INITIALIZE_SINGLETON
 
@@ skipping 37 matching lines @@
     type = ExitFrame::GetStateForFramePointer(
         Isolate::c_entry_fp(thread_), &state);
     handler_ = StackHandler::FromAddress(
         Isolate::handler(thread_));
   } else {
     ASSERT(fp_ != NULL);
     state.fp = fp_;
     state.sp = sp_;
     state.pc_address =
         reinterpret_cast<Address*>(StandardFrame::ComputePCAddress(fp_));
-    type = StackFrame::ComputeType(&state);
+    type = StackFrame::ComputeType(isolate(), &state);
   }
   if (SingletonFor(type) == NULL) return;
   frame_ = SingletonFor(type, &state);
 }
 
 
 StackFrame* StackFrameIterator::SingletonFor(StackFrame::Type type,
                                              StackFrame::State* state) {
   if (type == StackFrame::NONE) return NULL;
   StackFrame* result = SingletonFor(type);
@@ skipping 20 matching lines @@
 
 
 // -------------------------------------------------------------------------
 
 
 StackTraceFrameIterator::StackTraceFrameIterator() {
   if (!done() && !IsValidFrame()) Advance();
 }
 
 
+StackTraceFrameIterator::StackTraceFrameIterator(Isolate* isolate)
+    : JavaScriptFrameIterator(isolate) {
+  if (!done() && !IsValidFrame()) Advance();
+}
+
+
 void StackTraceFrameIterator::Advance() {
   while (true) {
     JavaScriptFrameIterator::Advance();
     if (done()) return;
     if (IsValidFrame()) return;
   }
 }
 
 bool StackTraceFrameIterator::IsValidFrame() {
     if (!frame()->function()->IsJSFunction()) return false;
@@ skipping 13 matching lines @@
   if (!validator_.IsValid(sp)) return false;
   StackFrame::State state;
   ExitFrame::FillState(fp, sp, &state);
   if (!validator_.IsValid(reinterpret_cast<Address>(state.pc_address))) {
     return false;
   }
   return *state.pc_address != NULL;
 }
 
 
+SafeStackFrameIterator::ActiveCountMaintainer::ActiveCountMaintainer(
+    Isolate* isolate)
+    : isolate_(isolate) {
+  isolate_->set_safe_stack_iterator_counter(
+      isolate_->safe_stack_iterator_counter() + 1);
+}
+
+
+SafeStackFrameIterator::ActiveCountMaintainer::~ActiveCountMaintainer() {
+  isolate_->set_safe_stack_iterator_counter(
+      isolate_->safe_stack_iterator_counter() - 1);
+}
+
+
 SafeStackFrameIterator::SafeStackFrameIterator(
     Isolate* isolate,
     Address fp, Address sp, Address low_bound, Address high_bound) :
-    maintainer_(),
+    maintainer_(isolate),
     stack_validator_(low_bound, high_bound),
     is_valid_top_(IsValidTop(isolate, low_bound, high_bound)),
     is_valid_fp_(IsWithinBounds(low_bound, high_bound, fp)),
     is_working_iterator_(is_valid_top_ || is_valid_fp_),
     iteration_done_(!is_working_iterator_),
     iterator_(isolate, is_valid_top_, is_valid_fp_ ? fp : NULL, sp) {
 }
 
+bool SafeStackFrameIterator::is_active(Isolate* isolate) {
+  return isolate->safe_stack_iterator_counter() > 0;
+}
+
 
 bool SafeStackFrameIterator::IsValidTop(Isolate* isolate,
                                         Address low_bound, Address high_bound) {
   ThreadLocalTop* top = isolate->thread_local_top();
   Address fp = Isolate::c_entry_fp(top);
   ExitFrameValidator validator(low_bound, high_bound);
   if (!validator.IsValidFP(fp)) return false;
   return Isolate::handler(top) != NULL;
 }
 
@@ skipping 80 matching lines @@
 void SafeStackTraceFrameIterator::Advance() {
   while (true) {
     SafeJavaScriptFrameIterator::Advance();
     if (done()) return;
     if (frame()->is_java_script()) return;
   }
 }
 #endif
 
 
-Code* StackFrame::GetSafepointData(Address pc,
+Code* StackFrame::GetSafepointData(Isolate* isolate,
+                                   Address pc,
                                    SafepointEntry* safepoint_entry,
                                    unsigned* stack_slots) {
-  Isolate* isolate = Isolate::Current();
   PcToCodeCache::PcToCodeCacheEntry* entry =
       isolate->pc_to_code_cache()->GetCacheEntry(pc);
   SafepointEntry cached_safepoint_entry = entry->safepoint_entry;
   if (!entry->safepoint_entry.is_valid()) {
     entry->safepoint_entry = entry->code->GetSafepointEntry(pc);
     ASSERT(entry->safepoint_entry.is_valid());
   } else {
     ASSERT(entry->safepoint_entry.Equals(entry->code->GetSafepointEntry(pc)));
   }
 
@@ skipping 20 matching lines @@
   Object* code = holder;
   v->VisitPointer(&code);
   if (code != holder) {
     holder = reinterpret_cast<Code*>(code);
     pc = holder->instruction_start() + pc_offset;
     *pc_address = pc;
   }
 }
 
 
-StackFrame::Type StackFrame::ComputeType(State* state) {
+StackFrame::Type StackFrame::ComputeType(Isolate* isolate, State* state) {
   ASSERT(state->fp != NULL);
   if (StandardFrame::IsArgumentsAdaptorFrame(state->fp)) {
     return ARGUMENTS_ADAPTOR;
   }
   // The marker and function offsets overlap. If the marker isn't a
   // smi then the frame is a JavaScript frame -- and the marker is
   // really the function.
   const int offset = StandardFrameConstants::kMarkerOffset;
   Object* marker = Memory::Object_at(state->fp + offset);
   if (!marker->IsSmi()) {
     // If we're using a "safe" stack iterator, we treat optimized
     // frames as normal JavaScript frames to avoid having to look
     // into the heap to determine the state. This is safe as long
     // as nobody tries to GC...
-    if (SafeStackFrameIterator::is_active()) return JAVA_SCRIPT;
-    Code::Kind kind = GetContainingCode(Isolate::Current(),
-                                        *(state->pc_address))->kind();
+    if (SafeStackFrameIterator::is_active(isolate))

[Vitaly Repeshko, 2011/04/04 20:37:08]

nit: Format one a single line if fits, use {} otherwise.

[mnaganov (inactive), 2011/04/05 08:28:23]

Done.

+      return JAVA_SCRIPT;
+    Code::Kind kind = GetContainingCode(isolate, *(state->pc_address))->kind();
     ASSERT(kind == Code::FUNCTION || kind == Code::OPTIMIZED_FUNCTION);
     return (kind == Code::OPTIMIZED_FUNCTION) ? OPTIMIZED : JAVA_SCRIPT;
   }
   return static_cast<StackFrame::Type>(Smi::cast(marker)->value());
 }
 
 
 
 StackFrame::Type StackFrame::GetCallerState(State* state) const {
   ComputeCallerState(state);
-  return ComputeType(state);
+  return ComputeType(isolate(), state);
 }
 
 
 Code* EntryFrame::unchecked_code() const {
   return HEAP->raw_unchecked_js_entry_code();
 }
 
 
 void EntryFrame::ComputeCallerState(State* state) const {
   GetCallerState(state);
@@ skipping 39 matching lines @@
 
 
 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(Isolate::Current()));
+  IteratePc(v, pc_address(), LookupCode());
   v->VisitPointer(&code_slot());
 }
 
 
 Address ExitFrame::GetCallerStackPointer() const {
   return fp() + ExitFrameConstants::kCallerSPDisplacement;
 }
 
 
 StackFrame::Type ExitFrame::GetStateForFramePointer(Address fp, State* state) {
@@ skipping 53 matching lines @@
 
 void OptimizedFrame::Iterate(ObjectVisitor* v) const {
 #ifdef DEBUG
   // Make sure that optimized frames do not contain any stack handlers.
   StackHandlerIterator it(this, top_handler());
   ASSERT(it.done());
 #endif
 
   // Make sure that we're not doing "safe" stack frame iteration. We cannot
   // possibly find pointers in optimized frames in that state.
-  ASSERT(!SafeStackFrameIterator::is_active());
+  ASSERT(!SafeStackFrameIterator::is_active(isolate()));
 
   // Compute the safepoint information.
   unsigned stack_slots = 0;
   SafepointEntry safepoint_entry;
   Code* code = StackFrame::GetSafepointData(
-      pc(), &safepoint_entry, &stack_slots);
+      isolate(), pc(), &safepoint_entry, &stack_slots);
   unsigned slot_space = stack_slots * kPointerSize;
 
   // Visit the outgoing parameters. This is usually dealt with by the
   // callee, but while GC'ing we artificially lower the number of
   // arguments to zero and let the caller deal with it.
   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.
@@ skipping 74 matching lines @@
 
 
 Code* JavaScriptFrame::unchecked_code() const {
   JSFunction* function = JSFunction::cast(this->function());
   return function->unchecked_code();
 }
 
 
 Address JavaScriptFrame::GetCallerStackPointer() const {
   int arguments;
-  if (SafeStackFrameIterator::is_active() ||
-      HEAP->gc_state() != Heap::NOT_IN_GC) {
+  if (SafeStackFrameIterator::is_active(isolate()) ||
+      isolate()->heap()->gc_state() != Heap::NOT_IN_GC) {
     // If the we are currently iterating the safe stack the
     // arguments for frames are traversed as if they were
     // expression stack elements of the calling frame. The reason for
     // this rather strange decision is that we cannot access the
     // function during mark-compact GCs when objects may have been marked.
     // In fact accessing heap objects (like function->shared() below)
     // at all during GC is problematic.
     arguments = 0;
   } else {
     // Compute the number of arguments by getting the number of formal
     // parameters of the function. We must remember to take the
     // receiver into account (+1).
     JSFunction* function = JSFunction::cast(this->function());
     arguments = function->shared()->formal_parameter_count() + 1;
   }
   const int offset = StandardFrameConstants::kCallerSPOffset;
   return fp() + offset + (arguments * kPointerSize);
 }
 
 
 void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) {
   ASSERT(functions->length() == 0);
   functions->Add(JSFunction::cast(function()));
 }
 
 
 void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
   ASSERT(functions->length() == 0);
-  Code* code_pointer = LookupCode(Isolate::Current());
+  Code* code_pointer = LookupCode();
   int offset = static_cast<int>(pc() - code_pointer->address());
   FrameSummary summary(receiver(),
                        JSFunction::cast(function()),
                        code_pointer,
                        offset,
                        IsConstructor());
   functions->Add(summary);
 }
 
 
@@ skipping 98 matching lines @@
     int* deopt_index) {
   ASSERT(is_optimized());
 
   JSFunction* opt_function = JSFunction::cast(function());
   Code* code = opt_function->code();
 
   // The code object may have been replaced by lazy deoptimization. Fall
   // back to a slow search in this case to find the original optimized
   // code object.
   if (!code->contains(pc())) {
-    code = Isolate::Current()->pc_to_code_cache()->GcSafeFindCodeForPc(pc());
+    code = isolate()->pc_to_code_cache()->GcSafeFindCodeForPc(pc());
   }
   ASSERT(code != NULL);
   ASSERT(code->kind() == Code::OPTIMIZED_FUNCTION);
 
   SafepointEntry safepoint_entry = code->GetSafepointEntry(pc());
   *deopt_index = safepoint_entry.deoptimization_index();
   ASSERT(*deopt_index != Safepoint::kNoDeoptimizationIndex);
 
   return DeoptimizationInputData::cast(code->deoptimization_data());
 }
@@ skipping 40 matching lines @@
 
 
 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::Current()->builtins()->builtin(
+  return isolate()->builtins()->builtin(
       Builtins::kArgumentsAdaptorTrampoline);
 }
 
 
 Code* InternalFrame::unchecked_code() const {
   const int offset = InternalFrameConstants::kCodeOffset;
   Object* code = Memory::Object_at(fp() + offset);
   ASSERT(code != NULL);
   return reinterpret_cast<Code*>(code);
 }
@@ skipping 174 matching lines @@
 
   accumulator->Add("}\n\n");
 }
 
 
 void EntryFrame::Iterate(ObjectVisitor* v) const {
   StackHandlerIterator it(this, top_handler());
   ASSERT(!it.done());
   StackHandler* handler = it.handler();
   ASSERT(handler->is_entry());
-  handler->Iterate(v, LookupCode(Isolate::Current()));
+  handler->Iterate(v, LookupCode());
 #ifdef DEBUG
   // Make sure that the entry frame does not contain more than one
   // stack handler.
   it.Advance();
   ASSERT(it.done());
 #endif
-  IteratePc(v, pc_address(), LookupCode(Isolate::Current()));
+  IteratePc(v, pc_address(), LookupCode());
 }
 
 
 void StandardFrame::IterateExpressions(ObjectVisitor* v) const {
   const int offset = StandardFrameConstants::kContextOffset;
   Object** base = &Memory::Object_at(sp());
   Object** limit = &Memory::Object_at(fp() + offset) + 1;
   for (StackHandlerIterator it(this, top_handler()); !it.done(); it.Advance()) {
     StackHandler* handler = it.handler();
     // Traverse pointers down to - but not including - the next
     // handler in the handler chain. Update the base to skip the
     // handler and allow the handler to traverse its own pointers.
     const Address address = handler->address();
     v->VisitPointers(base, reinterpret_cast<Object**>(address));
     base = reinterpret_cast<Object**>(address + StackHandlerConstants::kSize);
     // Traverse the pointers in the handler itself.
-    handler->Iterate(v, LookupCode(Isolate::Current()));
+    handler->Iterate(v, LookupCode());
   }
   v->VisitPointers(base, limit);
 }
 
 
 void JavaScriptFrame::Iterate(ObjectVisitor* v) const {
   IterateExpressions(v);
-  IteratePc(v, pc_address(), LookupCode(Isolate::Current()));
+  IteratePc(v, pc_address(), LookupCode());
   IterateArguments(v);
 }
 
 
 void JavaScriptFrame::IterateArguments(ObjectVisitor* v) const {
   // Traverse callee-saved registers, receiver, and parameters.
   const int kBaseOffset = JavaScriptFrameConstants::kLastParameterOffset;
   const int kLimitOffset = JavaScriptFrameConstants::kReceiverOffset;
   Object** base = &Memory::Object_at(fp() + kBaseOffset);
   Object** limit = &Memory::Object_at(caller_sp() + kLimitOffset) + 1;
   v->VisitPointers(base, limit);
 }
 
 
 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(Isolate::Current()));
+  IteratePc(v, pc_address(), LookupCode());
 }
 
 
 // -------------------------------------------------------------------------
 
 
 JavaScriptFrame* StackFrameLocator::FindJavaScriptFrame(int n) {
   ASSERT(n >= 0);
   for (int i = 0; i <= n; i++) {
     while (!iterator_.frame()->is_java_script()) iterator_.Advance();
@@ skipping 123 matching lines @@
   ZoneList<StackFrame*> list(10);
   for (StackFrameIterator it; !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame());
     list.Add(frame);
   }
   return list.ToVector();
 }
 
 
 } }  // namespace v8::internal