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Diffstat (limited to 'deps/v8/src/debug.cc')
| -rw-r--r-- | deps/v8/src/debug.cc | 2227 |
1 files changed, 2227 insertions, 0 deletions
diff --git a/deps/v8/src/debug.cc b/deps/v8/src/debug.cc new file mode 100644 index 0000000000..a4bb04dc62 --- /dev/null +++ b/deps/v8/src/debug.cc @@ -0,0 +1,2227 @@ +// 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 +// 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 "api.h" +#include "arguments.h" +#include "bootstrapper.h" +#include "code-stubs.h" +#include "compiler.h" +#include "debug.h" +#include "execution.h" +#include "global-handles.h" +#include "natives.h" +#include "stub-cache.h" +#include "log.h" + +namespace v8 { namespace internal { + +static void PrintLn(v8::Local<v8::Value> value) { + v8::Local<v8::String> s = value->ToString(); + char* data = NewArray<char>(s->Length() + 1); + if (data == NULL) { + V8::FatalProcessOutOfMemory("PrintLn"); + return; + } + s->WriteAscii(data); + PrintF("%s\n", data); + DeleteArray(data); +} + + +static Handle<Code> ComputeCallDebugBreak(int argc) { + CALL_HEAP_FUNCTION(StubCache::ComputeCallDebugBreak(argc), Code); +} + + +static Handle<Code> ComputeCallDebugPrepareStepIn(int argc) { + CALL_HEAP_FUNCTION(StubCache::ComputeCallDebugPrepareStepIn(argc), Code); +} + + +BreakLocationIterator::BreakLocationIterator(Handle<DebugInfo> debug_info, + BreakLocatorType type) { + debug_info_ = debug_info; + type_ = type; + reloc_iterator_ = NULL; + reloc_iterator_original_ = NULL; + Reset(); // Initialize the rest of the member variables. +} + + +BreakLocationIterator::~BreakLocationIterator() { + ASSERT(reloc_iterator_ != NULL); + ASSERT(reloc_iterator_original_ != NULL); + delete reloc_iterator_; + delete reloc_iterator_original_; +} + + +void BreakLocationIterator::Next() { + AssertNoAllocation nogc; + ASSERT(!RinfoDone()); + + // Iterate through reloc info for code and original code stopping at each + // breakable code target. + bool first = break_point_ == -1; + while (!RinfoDone()) { + if (!first) RinfoNext(); + first = false; + if (RinfoDone()) return; + + // Whenever a statement position or (plain) position is passed update the + // current value of these. + if (RelocInfo::IsPosition(rmode())) { + if (RelocInfo::IsStatementPosition(rmode())) { + statement_position_ = + rinfo()->data() - debug_info_->shared()->start_position(); + } + // Always update the position as we don't want that to be before the + // statement position. + position_ = rinfo()->data() - debug_info_->shared()->start_position(); + ASSERT(position_ >= 0); + ASSERT(statement_position_ >= 0); + } + + // Check for breakable code target. Look in the original code as setting + // break points can cause the code targets in the running (debugged) code to + // be of a different kind than in the original code. + if (RelocInfo::IsCodeTarget(rmode())) { + Address target = original_rinfo()->target_address(); + Code* code = Code::GetCodeFromTargetAddress(target); + if (code->is_inline_cache_stub() || RelocInfo::IsConstructCall(rmode())) { + break_point_++; + return; + } + if (code->kind() == Code::STUB) { + if (type_ == ALL_BREAK_LOCATIONS) { + if (Debug::IsBreakStub(code)) { + break_point_++; + return; + } + } else { + ASSERT(type_ == SOURCE_BREAK_LOCATIONS); + if (Debug::IsSourceBreakStub(code)) { + break_point_++; + return; + } + } + } + } + + // Check for break at return. + if (RelocInfo::IsJSReturn(rmode())) { + // Set the positions to the end of the function. + if (debug_info_->shared()->HasSourceCode()) { + position_ = debug_info_->shared()->end_position() - + debug_info_->shared()->start_position(); + } else { + position_ = 0; + } + statement_position_ = position_; + break_point_++; + return; + } + } +} + + +void BreakLocationIterator::Next(int count) { + while (count > 0) { + Next(); + count--; + } +} + + +// Find the break point closest to the supplied address. +void BreakLocationIterator::FindBreakLocationFromAddress(Address pc) { + // Run through all break points to locate the one closest to the address. + int closest_break_point = 0; + int distance = kMaxInt; + while (!Done()) { + // Check if this break point is closer that what was previously found. + if (this->pc() < pc && pc - this->pc() < distance) { + closest_break_point = break_point(); + distance = pc - this->pc(); + // Check whether we can't get any closer. + if (distance == 0) break; + } + Next(); + } + + // Move to the break point found. + Reset(); + Next(closest_break_point); +} + + +// Find the break point closest to the supplied source position. +void BreakLocationIterator::FindBreakLocationFromPosition(int position) { + // Run through all break points to locate the one closest to the source + // position. + int closest_break_point = 0; + int distance = kMaxInt; + while (!Done()) { + // Check if this break point is closer that what was previously found. + if (position <= statement_position() && + statement_position() - position < distance) { + closest_break_point = break_point(); + distance = statement_position() - position; + // Check whether we can't get any closer. + if (distance == 0) break; + } + Next(); + } + + // Move to the break point found. + Reset(); + Next(closest_break_point); +} + + +void BreakLocationIterator::Reset() { + // Create relocation iterators for the two code objects. + if (reloc_iterator_ != NULL) delete reloc_iterator_; + if (reloc_iterator_original_ != NULL) delete reloc_iterator_original_; + reloc_iterator_ = new RelocIterator(debug_info_->code()); + reloc_iterator_original_ = new RelocIterator(debug_info_->original_code()); + + // Position at the first break point. + break_point_ = -1; + position_ = 1; + statement_position_ = 1; + Next(); +} + + +bool BreakLocationIterator::Done() const { + return RinfoDone(); +} + + +void BreakLocationIterator::SetBreakPoint(Handle<Object> break_point_object) { + // If there is not already a real break point here patch code with debug + // break. + if (!HasBreakPoint()) { + SetDebugBreak(); + } + ASSERT(IsDebugBreak()); + // Set the break point information. + DebugInfo::SetBreakPoint(debug_info_, code_position(), + position(), statement_position(), + break_point_object); +} + + +void BreakLocationIterator::ClearBreakPoint(Handle<Object> break_point_object) { + // Clear the break point information. + DebugInfo::ClearBreakPoint(debug_info_, code_position(), break_point_object); + // If there are no more break points here remove the debug break. + if (!HasBreakPoint()) { + ClearDebugBreak(); + ASSERT(!IsDebugBreak()); + } +} + + +void BreakLocationIterator::SetOneShot() { + // If there is a real break point here no more to do. + if (HasBreakPoint()) { + ASSERT(IsDebugBreak()); + return; + } + + // Patch code with debug break. + SetDebugBreak(); +} + + +void BreakLocationIterator::ClearOneShot() { + // If there is a real break point here no more to do. + if (HasBreakPoint()) { + ASSERT(IsDebugBreak()); + return; + } + + // Patch code removing debug break. + ClearDebugBreak(); + ASSERT(!IsDebugBreak()); +} + + +void BreakLocationIterator::SetDebugBreak() { + // If there is already a break point here just return. This might happen if + // the same code is flooded with break points twice. Flooding the same + // function twice might happen when stepping in a function with an exception + // handler as the handler and the function is the same. + if (IsDebugBreak()) { + return; + } + + if (RelocInfo::IsJSReturn(rmode())) { + // Patch the frame exit code with a break point. + SetDebugBreakAtReturn(); + } else { + // Patch the original code with the current address as the current address + // might have changed by the inline caching since the code was copied. + original_rinfo()->set_target_address(rinfo()->target_address()); + + // Patch the code to invoke the builtin debug break function matching the + // calling convention used by the call site. + Handle<Code> dbgbrk_code(Debug::FindDebugBreak(rinfo())); + rinfo()->set_target_address(dbgbrk_code->entry()); + } + ASSERT(IsDebugBreak()); +} + + +void BreakLocationIterator::ClearDebugBreak() { + if (RelocInfo::IsJSReturn(rmode())) { + // Restore the frame exit code. + ClearDebugBreakAtReturn(); + } else { + // Patch the code to the original invoke. + rinfo()->set_target_address(original_rinfo()->target_address()); + } + ASSERT(!IsDebugBreak()); +} + + +void BreakLocationIterator::PrepareStepIn() { + HandleScope scope; + + // Step in can only be prepared if currently positioned on an IC call or + // construct call. + Address target = rinfo()->target_address(); + Code* code = Code::GetCodeFromTargetAddress(target); + if (code->is_call_stub()) { + // Step in through IC call is handled by the runtime system. Therefore make + // sure that the any current IC is cleared and the runtime system is + // called. If the executing code has a debug break at the location change + // the call in the original code as it is the code there that will be + // executed in place of the debug break call. + Handle<Code> stub = ComputeCallDebugPrepareStepIn(code->arguments_count()); + if (IsDebugBreak()) { + original_rinfo()->set_target_address(stub->entry()); + } else { + rinfo()->set_target_address(stub->entry()); + } + } else { + // Step in through constructs call requires no changes to the running code. + ASSERT(RelocInfo::IsConstructCall(rmode())); + } +} + + +// Check whether the break point is at a position which will exit the function. +bool BreakLocationIterator::IsExit() const { + return (RelocInfo::IsJSReturn(rmode())); +} + + +bool BreakLocationIterator::HasBreakPoint() { + return debug_info_->HasBreakPoint(code_position()); +} + + +// Check whether there is a debug break at the current position. +bool BreakLocationIterator::IsDebugBreak() { + if (RelocInfo::IsJSReturn(rmode())) { + return IsDebugBreakAtReturn(); + } else { + return Debug::IsDebugBreak(rinfo()->target_address()); + } +} + + +Object* BreakLocationIterator::BreakPointObjects() { + return debug_info_->GetBreakPointObjects(code_position()); +} + + +// Clear out all the debug break code. This is ONLY supposed to be used when +// shutting down the debugger as it will leave the break point information in +// DebugInfo even though the code is patched back to the non break point state. +void BreakLocationIterator::ClearAllDebugBreak() { + while (!Done()) { + ClearDebugBreak(); + Next(); + } +} + + +bool BreakLocationIterator::RinfoDone() const { + ASSERT(reloc_iterator_->done() == reloc_iterator_original_->done()); + return reloc_iterator_->done(); +} + + +void BreakLocationIterator::RinfoNext() { + reloc_iterator_->next(); + reloc_iterator_original_->next(); +#ifdef DEBUG + ASSERT(reloc_iterator_->done() == reloc_iterator_original_->done()); + if (!reloc_iterator_->done()) { + ASSERT(rmode() == original_rmode()); + } +#endif +} + + +bool Debug::has_break_points_ = false; +DebugInfoListNode* Debug::debug_info_list_ = NULL; + + +// Threading support. +void Debug::ThreadInit() { + thread_local_.break_count_ = 0; + thread_local_.break_id_ = 0; + thread_local_.break_frame_id_ = StackFrame::NO_ID; + thread_local_.last_step_action_ = StepNone; + thread_local_.last_statement_position_ = RelocInfo::kNoPosition; + thread_local_.step_count_ = 0; + thread_local_.last_fp_ = 0; + thread_local_.step_into_fp_ = 0; + thread_local_.after_break_target_ = 0; + thread_local_.debugger_entry_ = NULL; + thread_local_.preemption_pending_ = false; +} + + +JSCallerSavedBuffer Debug::registers_; +Debug::ThreadLocal Debug::thread_local_; + + +char* Debug::ArchiveDebug(char* storage) { + char* to = storage; + memcpy(to, reinterpret_cast<char*>(&thread_local_), sizeof(ThreadLocal)); + to += sizeof(ThreadLocal); + memcpy(to, reinterpret_cast<char*>(®isters_), sizeof(registers_)); + ThreadInit(); + ASSERT(to <= storage + ArchiveSpacePerThread()); + return storage + ArchiveSpacePerThread(); +} + + +char* Debug::RestoreDebug(char* storage) { + char* from = storage; + memcpy(reinterpret_cast<char*>(&thread_local_), from, sizeof(ThreadLocal)); + from += sizeof(ThreadLocal); + memcpy(reinterpret_cast<char*>(®isters_), from, sizeof(registers_)); + ASSERT(from <= storage + ArchiveSpacePerThread()); + return storage + ArchiveSpacePerThread(); +} + + +int Debug::ArchiveSpacePerThread() { + return sizeof(ThreadLocal) + sizeof(registers_); +} + + +// Default break enabled. +bool Debug::disable_break_ = false; + +// Default call debugger on uncaught exception. +bool Debug::break_on_exception_ = false; +bool Debug::break_on_uncaught_exception_ = true; + +Handle<Context> Debug::debug_context_ = Handle<Context>(); +Code* Debug::debug_break_return_entry_ = NULL; +Code* Debug::debug_break_return_ = NULL; + + +void Debug::HandleWeakDebugInfo(v8::Persistent<v8::Value> obj, void* data) { + DebugInfoListNode* node = reinterpret_cast<DebugInfoListNode*>(data); + RemoveDebugInfo(node->debug_info()); +#ifdef DEBUG + node = Debug::debug_info_list_; + while (node != NULL) { + ASSERT(node != reinterpret_cast<DebugInfoListNode*>(data)); + node = node->next(); + } +#endif +} + + +DebugInfoListNode::DebugInfoListNode(DebugInfo* debug_info): next_(NULL) { + // Globalize the request debug info object and make it weak. + debug_info_ = Handle<DebugInfo>::cast((GlobalHandles::Create(debug_info))); + GlobalHandles::MakeWeak(reinterpret_cast<Object**>(debug_info_.location()), + this, Debug::HandleWeakDebugInfo); +} + + +DebugInfoListNode::~DebugInfoListNode() { + GlobalHandles::Destroy(reinterpret_cast<Object**>(debug_info_.location())); +} + + +void Debug::Setup(bool create_heap_objects) { + ThreadInit(); + if (create_heap_objects) { + // Get code to handle entry to debug break on return. + debug_break_return_entry_ = + Builtins::builtin(Builtins::Return_DebugBreakEntry); + ASSERT(debug_break_return_entry_->IsCode()); + + // Get code to handle debug break on return. + debug_break_return_ = + Builtins::builtin(Builtins::Return_DebugBreak); + ASSERT(debug_break_return_->IsCode()); + } +} + + +bool Debug::CompileDebuggerScript(int index) { + HandleScope scope; + + // Bail out if the index is invalid. + if (index == -1) { + return false; + } + + // Find source and name for the requested script. + Handle<String> source_code = Bootstrapper::NativesSourceLookup(index); + Vector<const char> name = Natives::GetScriptName(index); + Handle<String> script_name = Factory::NewStringFromAscii(name); + + // Compile the script. + bool allow_natives_syntax = FLAG_allow_natives_syntax; + FLAG_allow_natives_syntax = true; + Handle<JSFunction> boilerplate; + boilerplate = Compiler::Compile(source_code, script_name, 0, 0, NULL, NULL); + FLAG_allow_natives_syntax = allow_natives_syntax; + + // Silently ignore stack overflows during compilation. + if (boilerplate.is_null()) { + ASSERT(Top::has_pending_exception()); + Top::clear_pending_exception(); + return false; + } + + // Execute the boilerplate function in the debugger context. + Handle<Context> context = Top::global_context(); + bool caught_exception = false; + Handle<JSFunction> function = + Factory::NewFunctionFromBoilerplate(boilerplate, context); + Handle<Object> result = + Execution::TryCall(function, Handle<Object>(context->global()), + 0, NULL, &caught_exception); + + // Check for caught exceptions. + if (caught_exception) { + Handle<Object> message = MessageHandler::MakeMessageObject( + "error_loading_debugger", NULL, HandleVector<Object>(&result, 1), + Handle<String>()); + MessageHandler::ReportMessage(NULL, message); + return false; + } + + // Mark this script as native and return successfully. + Handle<Script> script(Script::cast(function->shared()->script())); + script->set_type(Smi::FromInt(SCRIPT_TYPE_NATIVE)); + return true; +} + + +bool Debug::Load() { + // Return if debugger is already loaded. + if (IsLoaded()) return true; + + // Bail out if we're already in the process of compiling the native + // JavaScript source code for the debugger. + if (Debugger::compiling_natives() || Debugger::is_loading_debugger()) + return false; + Debugger::set_loading_debugger(true); + + // Disable breakpoints and interrupts while compiling and running the + // debugger scripts including the context creation code. + DisableBreak disable(true); + PostponeInterruptsScope postpone; + + // Create the debugger context. + HandleScope scope; + Handle<Context> context = + Bootstrapper::CreateEnvironment(Handle<Object>::null(), + v8::Handle<ObjectTemplate>(), + NULL); + + // Use the debugger context. + SaveContext save; + Top::set_context(*context); + + // Expose the builtins object in the debugger context. + Handle<String> key = Factory::LookupAsciiSymbol("builtins"); + Handle<GlobalObject> global = Handle<GlobalObject>(context->global()); + SetProperty(global, key, Handle<Object>(global->builtins()), NONE); + + // Compile the JavaScript for the debugger in the debugger context. + Debugger::set_compiling_natives(true); + bool caught_exception = + !CompileDebuggerScript(Natives::GetIndex("mirror")) || + !CompileDebuggerScript(Natives::GetIndex("debug")); + Debugger::set_compiling_natives(false); + + // Make sure we mark the debugger as not loading before we might + // return. + Debugger::set_loading_debugger(false); + + // Check for caught exceptions. + if (caught_exception) return false; + + // Debugger loaded. + debug_context_ = Handle<Context>::cast(GlobalHandles::Create(*context)); + return true; +} + + +void Debug::Unload() { + // Return debugger is not loaded. + if (!IsLoaded()) { + return; + } + + // Clear debugger context global handle. + GlobalHandles::Destroy(reinterpret_cast<Object**>(debug_context_.location())); + debug_context_ = Handle<Context>(); +} + + +// Set the flag indicating that preemption happened during debugging. +void Debug::PreemptionWhileInDebugger() { + ASSERT(InDebugger()); + Debug::set_preemption_pending(true); +} + + +void Debug::Iterate(ObjectVisitor* v) { + v->VisitPointer(bit_cast<Object**, Code**>(&(debug_break_return_entry_))); + v->VisitPointer(bit_cast<Object**, Code**>(&(debug_break_return_))); +} + + +Object* Debug::Break(Arguments args) { + HandleScope scope; + ASSERT(args.length() == 0); + + // Get the top-most JavaScript frame. + JavaScriptFrameIterator it; + JavaScriptFrame* frame = it.frame(); + + // Just continue if breaks are disabled or debugger cannot be loaded. + if (disable_break() || !Load()) { + SetAfterBreakTarget(frame); + return Heap::undefined_value(); + } + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter()) { + return Heap::undefined_value(); + } + + // Postpone interrupt during breakpoint processing. + PostponeInterruptsScope postpone; + + // Get the debug info (create it if it does not exist). + Handle<SharedFunctionInfo> shared = + Handle<SharedFunctionInfo>(JSFunction::cast(frame->function())->shared()); + Handle<DebugInfo> debug_info = GetDebugInfo(shared); + + // Find the break point where execution has stopped. + BreakLocationIterator break_location_iterator(debug_info, + ALL_BREAK_LOCATIONS); + break_location_iterator.FindBreakLocationFromAddress(frame->pc()); + + // Check whether step next reached a new statement. + if (!StepNextContinue(&break_location_iterator, frame)) { + // Decrease steps left if performing multiple steps. + if (thread_local_.step_count_ > 0) { + thread_local_.step_count_--; + } + } + + // If there is one or more real break points check whether any of these are + // triggered. + Handle<Object> break_points_hit(Heap::undefined_value()); + if (break_location_iterator.HasBreakPoint()) { + Handle<Object> break_point_objects = + Handle<Object>(break_location_iterator.BreakPointObjects()); + break_points_hit = CheckBreakPoints(break_point_objects); + } + + // Notify debugger if a real break point is triggered or if performing single + // stepping with no more steps to perform. Otherwise do another step. + if (!break_points_hit->IsUndefined() || + (thread_local_.last_step_action_ != StepNone && + thread_local_.step_count_ == 0)) { + // Clear all current stepping setup. + ClearStepping(); + + // Notify the debug event listeners. + Debugger::OnDebugBreak(break_points_hit, false); + } else if (thread_local_.last_step_action_ != StepNone) { + // Hold on to last step action as it is cleared by the call to + // ClearStepping. + StepAction step_action = thread_local_.last_step_action_; + int step_count = thread_local_.step_count_; + + // Clear all current stepping setup. + ClearStepping(); + + // Set up for the remaining steps. + PrepareStep(step_action, step_count); + } + + // Install jump to the call address which was overwritten. + SetAfterBreakTarget(frame); + + return Heap::undefined_value(); +} + + +// Check the break point objects for whether one or more are actually +// triggered. This function returns a JSArray with the break point objects +// which is triggered. +Handle<Object> Debug::CheckBreakPoints(Handle<Object> break_point_objects) { + int break_points_hit_count = 0; + Handle<JSArray> break_points_hit = Factory::NewJSArray(1); + + // If there are multiple break points they are in a FixedArray. + ASSERT(!break_point_objects->IsUndefined()); + if (break_point_objects->IsFixedArray()) { + Handle<FixedArray> array(FixedArray::cast(*break_point_objects)); + for (int i = 0; i < array->length(); i++) { + Handle<Object> o(array->get(i)); + if (CheckBreakPoint(o)) { + break_points_hit->SetElement(break_points_hit_count++, *o); + } + } + } else { + if (CheckBreakPoint(break_point_objects)) { + break_points_hit->SetElement(break_points_hit_count++, + *break_point_objects); + } + } + + // Return undefined if no break points where triggered. + if (break_points_hit_count == 0) { + return Factory::undefined_value(); + } + return break_points_hit; +} + + +// Check whether a single break point object is triggered. +bool Debug::CheckBreakPoint(Handle<Object> break_point_object) { + HandleScope scope; + + // Ignore check if break point object is not a JSObject. + if (!break_point_object->IsJSObject()) return true; + + // Get the function CheckBreakPoint (defined in debug.js). + Handle<JSFunction> check_break_point = + Handle<JSFunction>(JSFunction::cast( + debug_context()->global()->GetProperty( + *Factory::LookupAsciiSymbol("IsBreakPointTriggered")))); + + // Get the break id as an object. + Handle<Object> break_id = Factory::NewNumberFromInt(Debug::break_id()); + + // Call HandleBreakPointx. + bool caught_exception = false; + const int argc = 2; + Object** argv[argc] = { + break_id.location(), + reinterpret_cast<Object**>(break_point_object.location()) + }; + Handle<Object> result = Execution::TryCall(check_break_point, + Top::builtins(), argc, argv, + &caught_exception); + + // If exception or non boolean result handle as not triggered + if (caught_exception || !result->IsBoolean()) { + return false; + } + + // Return whether the break point is triggered. + return *result == Heap::true_value(); +} + + +// Check whether the function has debug information. +bool Debug::HasDebugInfo(Handle<SharedFunctionInfo> shared) { + return !shared->debug_info()->IsUndefined(); +} + + +// Return the debug info for this function. EnsureDebugInfo must be called +// prior to ensure the debug info has been generated for shared. +Handle<DebugInfo> Debug::GetDebugInfo(Handle<SharedFunctionInfo> shared) { + ASSERT(HasDebugInfo(shared)); + return Handle<DebugInfo>(DebugInfo::cast(shared->debug_info())); +} + + +void Debug::SetBreakPoint(Handle<SharedFunctionInfo> shared, + int source_position, + Handle<Object> break_point_object) { + HandleScope scope; + + if (!EnsureDebugInfo(shared)) { + // Return if retrieving debug info failed. + return; + } + + Handle<DebugInfo> debug_info = GetDebugInfo(shared); + // Source positions starts with zero. + ASSERT(source_position >= 0); + + // Find the break point and change it. + BreakLocationIterator it(debug_info, SOURCE_BREAK_LOCATIONS); + it.FindBreakLocationFromPosition(source_position); + it.SetBreakPoint(break_point_object); + + // At least one active break point now. + ASSERT(debug_info->GetBreakPointCount() > 0); +} + + +void Debug::ClearBreakPoint(Handle<Object> break_point_object) { + HandleScope scope; + + DebugInfoListNode* node = debug_info_list_; + while (node != NULL) { + Object* result = DebugInfo::FindBreakPointInfo(node->debug_info(), + break_point_object); + if (!result->IsUndefined()) { + // Get information in the break point. + BreakPointInfo* break_point_info = BreakPointInfo::cast(result); + Handle<DebugInfo> debug_info = node->debug_info(); + Handle<SharedFunctionInfo> shared(debug_info->shared()); + int source_position = break_point_info->statement_position()->value(); + + // Source positions starts with zero. + ASSERT(source_position >= 0); + + // Find the break point and clear it. + BreakLocationIterator it(debug_info, SOURCE_BREAK_LOCATIONS); + it.FindBreakLocationFromPosition(source_position); + it.ClearBreakPoint(break_point_object); + + // If there are no more break points left remove the debug info for this + // function. + if (debug_info->GetBreakPointCount() == 0) { + RemoveDebugInfo(debug_info); + } + + return; + } + node = node->next(); + } +} + + +void Debug::ClearAllBreakPoints() { + DebugInfoListNode* node = debug_info_list_; + while (node != NULL) { + // Remove all debug break code. + BreakLocationIterator it(node->debug_info(), ALL_BREAK_LOCATIONS); + it.ClearAllDebugBreak(); + node = node->next(); + } + + // Remove all debug info. + while (debug_info_list_ != NULL) { + RemoveDebugInfo(debug_info_list_->debug_info()); + } +} + + +void Debug::FloodWithOneShot(Handle<SharedFunctionInfo> shared) { + // Make sure the function has setup the debug info. + if (!EnsureDebugInfo(shared)) { + // Return if we failed to retrieve the debug info. + return; + } + + // Flood the function with break points. + BreakLocationIterator it(GetDebugInfo(shared), ALL_BREAK_LOCATIONS); + while (!it.Done()) { + it.SetOneShot(); + it.Next(); + } +} + + +void Debug::FloodHandlerWithOneShot() { + // Iterate through the JavaScript stack looking for handlers. + StackFrame::Id id = break_frame_id(); + if (id == StackFrame::NO_ID) { + // If there is no JavaScript stack don't do anything. + return; + } + for (JavaScriptFrameIterator it(id); !it.done(); it.Advance()) { + JavaScriptFrame* frame = it.frame(); + if (frame->HasHandler()) { + Handle<SharedFunctionInfo> shared = + Handle<SharedFunctionInfo>( + JSFunction::cast(frame->function())->shared()); + // Flood the function with the catch block with break points + FloodWithOneShot(shared); + return; + } + } +} + + +void Debug::ChangeBreakOnException(ExceptionBreakType type, bool enable) { + if (type == BreakUncaughtException) { + break_on_uncaught_exception_ = enable; + } else { + break_on_exception_ = enable; + } +} + + +void Debug::PrepareStep(StepAction step_action, int step_count) { + HandleScope scope; + ASSERT(Debug::InDebugger()); + + // Remember this step action and count. + thread_local_.last_step_action_ = step_action; + thread_local_.step_count_ = step_count; + + // Get the frame where the execution has stopped and skip the debug frame if + // any. The debug frame will only be present if execution was stopped due to + // hitting a break point. In other situations (e.g. unhandled exception) the + // debug frame is not present. + StackFrame::Id id = break_frame_id(); + if (id == StackFrame::NO_ID) { + // If there is no JavaScript stack don't do anything. + return; + } + JavaScriptFrameIterator frames_it(id); + JavaScriptFrame* frame = frames_it.frame(); + + // First of all ensure there is one-shot break points in the top handler + // if any. + FloodHandlerWithOneShot(); + + // If the function on the top frame is unresolved perform step out. This will + // be the case when calling unknown functions and having the debugger stopped + // in an unhandled exception. + if (!frame->function()->IsJSFunction()) { + // Step out: Find the calling JavaScript frame and flood it with + // breakpoints. + frames_it.Advance(); + // Fill the function to return to with one-shot break points. + JSFunction* function = JSFunction::cast(frames_it.frame()->function()); + FloodWithOneShot(Handle<SharedFunctionInfo>(function->shared())); + return; + } + + // Get the debug info (create it if it does not exist). + Handle<SharedFunctionInfo> shared = + Handle<SharedFunctionInfo>(JSFunction::cast(frame->function())->shared()); + if (!EnsureDebugInfo(shared)) { + // Return if ensuring debug info failed. + return; + } + Handle<DebugInfo> debug_info = GetDebugInfo(shared); + + // Find the break location where execution has stopped. + BreakLocationIterator it(debug_info, ALL_BREAK_LOCATIONS); + it.FindBreakLocationFromAddress(frame->pc()); + + // Compute whether or not the target is a call target. + bool is_call_target = false; + if (RelocInfo::IsCodeTarget(it.rinfo()->rmode())) { + Address target = it.rinfo()->target_address(); + Code* code = Code::GetCodeFromTargetAddress(target); + if (code->is_call_stub()) is_call_target = true; + } + + // If this is the last break code target step out is the only possibility. + if (it.IsExit() || step_action == StepOut) { + // Step out: If there is a JavaScript caller frame, we need to + // flood it with breakpoints. + frames_it.Advance(); + if (!frames_it.done()) { + // Fill the function to return to with one-shot break points. + JSFunction* function = JSFunction::cast(frames_it.frame()->function()); + FloodWithOneShot(Handle<SharedFunctionInfo>(function->shared())); + } + } else if (!(is_call_target || RelocInfo::IsConstructCall(it.rmode())) || + step_action == StepNext || step_action == StepMin) { + // Step next or step min. + + // Fill the current function with one-shot break points. + FloodWithOneShot(shared); + + // Remember source position and frame to handle step next. + thread_local_.last_statement_position_ = + debug_info->code()->SourceStatementPosition(frame->pc()); + thread_local_.last_fp_ = frame->fp(); + } else { + // Fill the current function with one-shot break points even for step in on + // a call target as the function called might be a native function for + // which step in will not stop. + FloodWithOneShot(shared); + + // Step in or Step in min + it.PrepareStepIn(); + ActivateStepIn(frame); + } +} + + +// Check whether the current debug break should be reported to the debugger. It +// is used to have step next and step in only report break back to the debugger +// if on a different frame or in a different statement. In some situations +// there will be several break points in the same statement when the code is +// flooded with one-shot break points. This function helps to perform several +// steps before reporting break back to the debugger. +bool Debug::StepNextContinue(BreakLocationIterator* break_location_iterator, + JavaScriptFrame* frame) { + // If the step last action was step next or step in make sure that a new + // statement is hit. + if (thread_local_.last_step_action_ == StepNext || + thread_local_.last_step_action_ == StepIn) { + // Never continue if returning from function. + if (break_location_iterator->IsExit()) return false; + + // Continue if we are still on the same frame and in the same statement. + int current_statement_position = + break_location_iterator->code()->SourceStatementPosition(frame->pc()); + return thread_local_.last_fp_ == frame->fp() && + thread_local_.last_statement_position_ == current_statement_position; + } + + // No step next action - don't continue. + return false; +} + + +// Check whether the code object at the specified address is a debug break code +// object. +bool Debug::IsDebugBreak(Address addr) { + Code* code = Code::GetCodeFromTargetAddress(addr); + return code->ic_state() == DEBUG_BREAK; +} + + +// Check whether a code stub with the specified major key is a possible break +// point location when looking for source break locations. +bool Debug::IsSourceBreakStub(Code* code) { + CodeStub::Major major_key = code->major_key(); + return major_key == CodeStub::CallFunction; +} + + +// Check whether a code stub with the specified major key is a possible break +// location. +bool Debug::IsBreakStub(Code* code) { + CodeStub::Major major_key = code->major_key(); + return major_key == CodeStub::CallFunction || + major_key == CodeStub::StackCheck; +} + + +// Find the builtin to use for invoking the debug break +Handle<Code> Debug::FindDebugBreak(RelocInfo* rinfo) { + // Find the builtin debug break function matching the calling convention + // used by the call site. + RelocInfo::Mode mode = rinfo->rmode(); + + if (RelocInfo::IsCodeTarget(mode)) { + Address target = rinfo->target_address(); + Code* code = Code::GetCodeFromTargetAddress(target); + if (code->is_inline_cache_stub()) { + if (code->is_call_stub()) { + return ComputeCallDebugBreak(code->arguments_count()); + } + if (code->is_load_stub()) { + return Handle<Code>(Builtins::builtin(Builtins::LoadIC_DebugBreak)); + } + if (code->is_store_stub()) { + return Handle<Code>(Builtins::builtin(Builtins::StoreIC_DebugBreak)); + } + if (code->is_keyed_load_stub()) { + Handle<Code> result = + Handle<Code>(Builtins::builtin(Builtins::KeyedLoadIC_DebugBreak)); + return result; + } + if (code->is_keyed_store_stub()) { + Handle<Code> result = + Handle<Code>(Builtins::builtin(Builtins::KeyedStoreIC_DebugBreak)); + return result; + } + } + if (RelocInfo::IsConstructCall(mode)) { + Handle<Code> result = + Handle<Code>(Builtins::builtin(Builtins::ConstructCall_DebugBreak)); + return result; + } + if (code->kind() == Code::STUB) { + ASSERT(code->major_key() == CodeStub::CallFunction || + code->major_key() == CodeStub::StackCheck); + Handle<Code> result = + Handle<Code>(Builtins::builtin(Builtins::StubNoRegisters_DebugBreak)); + return result; + } + } + + UNREACHABLE(); + return Handle<Code>::null(); +} + + +// Simple function for returning the source positions for active break points. +Handle<Object> Debug::GetSourceBreakLocations( + Handle<SharedFunctionInfo> shared) { + if (!HasDebugInfo(shared)) return Handle<Object>(Heap::undefined_value()); + Handle<DebugInfo> debug_info = GetDebugInfo(shared); + if (debug_info->GetBreakPointCount() == 0) { + return Handle<Object>(Heap::undefined_value()); + } + Handle<FixedArray> locations = + Factory::NewFixedArray(debug_info->GetBreakPointCount()); + int count = 0; + for (int i = 0; i < debug_info->break_points()->length(); i++) { + if (!debug_info->break_points()->get(i)->IsUndefined()) { + BreakPointInfo* break_point_info = + BreakPointInfo::cast(debug_info->break_points()->get(i)); + if (break_point_info->GetBreakPointCount() > 0) { + locations->set(count++, break_point_info->statement_position()); + } + } + } + return locations; +} + + +void Debug::NewBreak(StackFrame::Id break_frame_id) { + thread_local_.break_frame_id_ = break_frame_id; + thread_local_.break_id_ = ++thread_local_.break_count_; +} + + +void Debug::SetBreak(StackFrame::Id break_frame_id, int break_id) { + thread_local_.break_frame_id_ = break_frame_id; + thread_local_.break_id_ = break_id; +} + + +// Handle stepping into a function. +void Debug::HandleStepIn(Handle<JSFunction> function, + Address fp, + bool is_constructor) { + // If the frame pointer is not supplied by the caller find it. + if (fp == 0) { + StackFrameIterator it; + it.Advance(); + // For constructor functions skip another frame. + if (is_constructor) { + ASSERT(it.frame()->is_construct()); + it.Advance(); + } + fp = it.frame()->fp(); + } + + // Flood the function with one-shot break points if it is called from where + // step into was requested. + if (fp == Debug::step_in_fp()) { + // Don't allow step into functions in the native context. + if (function->context()->global() != Top::context()->builtins()) { + if (function->shared()->code() == + Builtins::builtin(Builtins::FunctionApply) || + function->shared()->code() == + Builtins::builtin(Builtins::FunctionCall)) { + // Handle function.apply and function.call separately to flood the + // function to be called and not the code for Builtins::FunctionApply or + // Builtins::FunctionCall. At the point of the call IC to call either + // Builtins::FunctionApply or Builtins::FunctionCall the expression + // stack has the following content: + // symbol "apply" or "call" + // function apply or call was called on + // receiver for apply or call (first parameter to apply or call) + // ... further arguments to apply or call. + JavaScriptFrameIterator it; + ASSERT(it.frame()->fp() == fp); + ASSERT(it.frame()->GetExpression(1)->IsJSFunction()); + if (it.frame()->GetExpression(1)->IsJSFunction()) { + Handle<JSFunction> + actual_function(JSFunction::cast(it.frame()->GetExpression(1))); + Handle<SharedFunctionInfo> actual_shared(actual_function->shared()); + Debug::FloodWithOneShot(actual_shared); + } + } else { + Debug::FloodWithOneShot(Handle<SharedFunctionInfo>(function->shared())); + } + } + } +} + + +void Debug::ClearStepping() { + // Clear the various stepping setup. + ClearOneShot(); + ClearStepIn(); + ClearStepNext(); + + // Clear multiple step counter. + thread_local_.step_count_ = 0; +} + +// Clears all the one-shot break points that are currently set. Normally this +// function is called each time a break point is hit as one shot break points +// are used to support stepping. +void Debug::ClearOneShot() { + // The current implementation just runs through all the breakpoints. When the + // last break point for a function is removed that function is automatically + // removed from the list. + + DebugInfoListNode* node = debug_info_list_; + while (node != NULL) { + BreakLocationIterator it(node->debug_info(), ALL_BREAK_LOCATIONS); + while (!it.Done()) { + it.ClearOneShot(); + it.Next(); + } + node = node->next(); + } +} + + +void Debug::ActivateStepIn(StackFrame* frame) { + thread_local_.step_into_fp_ = frame->fp(); +} + + +void Debug::ClearStepIn() { + thread_local_.step_into_fp_ = 0; +} + + +void Debug::ClearStepNext() { + thread_local_.last_step_action_ = StepNone; + thread_local_.last_statement_position_ = RelocInfo::kNoPosition; + thread_local_.last_fp_ = 0; +} + + +bool Debug::EnsureCompiled(Handle<SharedFunctionInfo> shared) { + if (shared->is_compiled()) return true; + return CompileLazyShared(shared, CLEAR_EXCEPTION, 0); +} + + +// Ensures the debug information is present for shared. +bool Debug::EnsureDebugInfo(Handle<SharedFunctionInfo> shared) { + // Return if we already have the debug info for shared. + if (HasDebugInfo(shared)) return true; + + // Ensure shared in compiled. Return false if this failed. + if (!EnsureCompiled(shared)) return false; + + // Create the debug info object. + Handle<DebugInfo> debug_info = Factory::NewDebugInfo(shared); + + // Add debug info to the list. + DebugInfoListNode* node = new DebugInfoListNode(*debug_info); + node->set_next(debug_info_list_); + debug_info_list_ = node; + + // Now there is at least one break point. + has_break_points_ = true; + + return true; +} + + +void Debug::RemoveDebugInfo(Handle<DebugInfo> debug_info) { + ASSERT(debug_info_list_ != NULL); + // Run through the debug info objects to find this one and remove it. + DebugInfoListNode* prev = NULL; + DebugInfoListNode* current = debug_info_list_; + while (current != NULL) { + if (*current->debug_info() == *debug_info) { + // Unlink from list. If prev is NULL we are looking at the first element. + if (prev == NULL) { + debug_info_list_ = current->next(); + } else { + prev->set_next(current->next()); + } + current->debug_info()->shared()->set_debug_info(Heap::undefined_value()); + delete current; + + // If there are no more debug info objects there are not more break + // points. + has_break_points_ = debug_info_list_ != NULL; + + return; + } + // Move to next in list. + prev = current; + current = current->next(); + } + UNREACHABLE(); +} + + +void Debug::SetAfterBreakTarget(JavaScriptFrame* frame) { + HandleScope scope; + + // Get the executing function in which the debug break occurred. + Handle<SharedFunctionInfo> shared = + Handle<SharedFunctionInfo>(JSFunction::cast(frame->function())->shared()); + if (!EnsureDebugInfo(shared)) { + // Return if we failed to retrieve the debug info. + return; + } + Handle<DebugInfo> debug_info = GetDebugInfo(shared); + Handle<Code> code(debug_info->code()); + Handle<Code> original_code(debug_info->original_code()); +#ifdef DEBUG + // Get the code which is actually executing. + Handle<Code> frame_code(frame->code()); + ASSERT(frame_code.is_identical_to(code)); +#endif + + // Find the call address in the running code. This address holds the call to + // either a DebugBreakXXX or to the debug break return entry code if the + // break point is still active after processing the break point. + Address addr = frame->pc() - Assembler::kTargetAddrToReturnAddrDist; + + // Check if the location is at JS exit. + bool at_js_exit = false; + RelocIterator it(debug_info->code()); + while (!it.done()) { + if (RelocInfo::IsJSReturn(it.rinfo()->rmode())) { + at_js_exit = it.rinfo()->pc() == addr - 1; + } + it.next(); + } + + // Handle the jump to continue execution after break point depending on the + // break location. + if (at_js_exit) { + // First check if the call in the code is still the debug break return + // entry code. If it is the break point is still active. If not the break + // point was removed during break point processing. + if (Assembler::target_address_at(addr) == + debug_break_return_entry()->entry()) { + // Break point still active. Jump to the corresponding place in the + // original code. + addr += original_code->instruction_start() - code->instruction_start(); + } + + // Move one byte back to where the call instruction was placed. + thread_local_.after_break_target_ = addr - 1; + } else { + // Check if there still is a debug break call at the target address. If the + // break point has been removed it will have disappeared. If it have + // disappeared don't try to look in the original code as the running code + // will have the right address. This takes care of the case where the last + // break point is removed from the function and therefore no "original code" + // is available. If the debug break call is still there find the address in + // the original code. + if (IsDebugBreak(Assembler::target_address_at(addr))) { + // If the break point is still there find the call address which was + // overwritten in the original code by the call to DebugBreakXXX. + + // Find the corresponding address in the original code. + addr += original_code->instruction_start() - code->instruction_start(); + } + + // Install jump to the call address in the original code. This will be the + // call which was overwritten by the call to DebugBreakXXX. + thread_local_.after_break_target_ = Assembler::target_address_at(addr); + } +} + + +bool Debug::IsDebugGlobal(GlobalObject* global) { + return IsLoaded() && global == Debug::debug_context()->global(); +} + + +void Debug::ClearMirrorCache() { + HandleScope scope; + ASSERT(Top::context() == *Debug::debug_context()); + + // Clear the mirror cache. + Handle<String> function_name = + Factory::LookupSymbol(CStrVector("ClearMirrorCache")); + Handle<Object> fun(Top::global()->GetProperty(*function_name)); + ASSERT(fun->IsJSFunction()); + bool caught_exception; + Handle<Object> js_object = Execution::TryCall( + Handle<JSFunction>::cast(fun), + Handle<JSObject>(Debug::debug_context()->global()), + 0, NULL, &caught_exception); +} + + +Mutex* Debugger::debugger_access_ = OS::CreateMutex(); +Handle<Object> Debugger::event_listener_ = Handle<Object>(); +Handle<Object> Debugger::event_listener_data_ = Handle<Object>(); +bool Debugger::compiling_natives_ = false; +bool Debugger::is_loading_debugger_ = false; +bool Debugger::never_unload_debugger_ = false; +DebugMessageThread* Debugger::message_thread_ = NULL; +v8::DebugMessageHandler Debugger::message_handler_ = NULL; +bool Debugger::message_handler_cleared_ = false; +void* Debugger::message_handler_data_ = NULL; +v8::DebugHostDispatchHandler Debugger::host_dispatch_handler_ = NULL; +void* Debugger::host_dispatch_handler_data_ = NULL; +DebuggerAgent* Debugger::agent_ = NULL; +LockingMessageQueue Debugger::command_queue_(kQueueInitialSize); +LockingMessageQueue Debugger::message_queue_(kQueueInitialSize); +Semaphore* Debugger::command_received_ = OS::CreateSemaphore(0); +Semaphore* Debugger::message_received_ = OS::CreateSemaphore(0); + + +Handle<Object> Debugger::MakeJSObject(Vector<const char> constructor_name, + int argc, Object*** argv, + bool* caught_exception) { + ASSERT(Top::context() == *Debug::debug_context()); + + // Create the execution state object. + Handle<String> constructor_str = Factory::LookupSymbol(constructor_name); + Handle<Object> constructor(Top::global()->GetProperty(*constructor_str)); + ASSERT(constructor->IsJSFunction()); + if (!constructor->IsJSFunction()) { + *caught_exception = true; + return Factory::undefined_value(); + } + Handle<Object> js_object = Execution::TryCall( + Handle<JSFunction>::cast(constructor), + Handle<JSObject>(Debug::debug_context()->global()), argc, argv, + caught_exception); + return js_object; +} + + +Handle<Object> Debugger::MakeExecutionState(bool* caught_exception) { + // Create the execution state object. + Handle<Object> break_id = Factory::NewNumberFromInt(Debug::break_id()); + const int argc = 1; + Object** argv[argc] = { break_id.location() }; + return MakeJSObject(CStrVector("MakeExecutionState"), + argc, argv, caught_exception); +} + + +Handle<Object> Debugger::MakeBreakEvent(Handle<Object> exec_state, + Handle<Object> break_points_hit, + bool* caught_exception) { + // Create the new break event object. + const int argc = 2; + Object** argv[argc] = { exec_state.location(), + break_points_hit.location() }; + return MakeJSObject(CStrVector("MakeBreakEvent"), + argc, + argv, + caught_exception); +} + + +Handle<Object> Debugger::MakeExceptionEvent(Handle<Object> exec_state, + Handle<Object> exception, + bool uncaught, + bool* caught_exception) { + // Create the new exception event object. + const int argc = 3; + Object** argv[argc] = { exec_state.location(), + exception.location(), + uncaught ? Factory::true_value().location() : + Factory::false_value().location()}; + return MakeJSObject(CStrVector("MakeExceptionEvent"), + argc, argv, caught_exception); +} + + +Handle<Object> Debugger::MakeNewFunctionEvent(Handle<Object> function, + bool* caught_exception) { + // Create the new function event object. + const int argc = 1; + Object** argv[argc] = { function.location() }; + return MakeJSObject(CStrVector("MakeNewFunctionEvent"), + argc, argv, caught_exception); +} + + +Handle<Object> Debugger::MakeCompileEvent(Handle<Script> script, + bool before, + bool* caught_exception) { + // Create the compile event object. + Handle<Object> exec_state = MakeExecutionState(caught_exception); + Handle<Object> script_wrapper = GetScriptWrapper(script); + const int argc = 3; + Object** argv[argc] = { exec_state.location(), + script_wrapper.location(), + before ? Factory::true_value().location() : + Factory::false_value().location() }; + + return MakeJSObject(CStrVector("MakeCompileEvent"), + argc, + argv, + caught_exception); +} + + +void Debugger::OnException(Handle<Object> exception, bool uncaught) { + HandleScope scope; + + // Bail out based on state or if there is no listener for this event + if (Debug::InDebugger()) return; + if (!Debugger::EventActive(v8::Exception)) return; + + // Bail out if exception breaks are not active + if (uncaught) { + // Uncaught exceptions are reported by either flags. + if (!(Debug::break_on_uncaught_exception() || + Debug::break_on_exception())) return; + } else { + // Caught exceptions are reported is activated. + if (!Debug::break_on_exception()) return; + } + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter()) return; + + // Clear all current stepping setup. + Debug::ClearStepping(); + // Create the event data object. + bool caught_exception = false; + Handle<Object> exec_state = MakeExecutionState(&caught_exception); + Handle<Object> event_data; + if (!caught_exception) { + event_data = MakeExceptionEvent(exec_state, exception, uncaught, + &caught_exception); + } + // Bail out and don't call debugger if exception. + if (caught_exception) { + return; + } + + // Process debug event + ProcessDebugEvent(v8::Exception, event_data, false); + // Return to continue execution from where the exception was thrown. +} + + +void Debugger::OnDebugBreak(Handle<Object> break_points_hit, + bool auto_continue) { + HandleScope scope; + + // Debugger has already been entered by caller. + ASSERT(Top::context() == *Debug::debug_context()); + + // Bail out if there is no listener for this event + if (!Debugger::EventActive(v8::Break)) return; + + // Debugger must be entered in advance. + ASSERT(Top::context() == *Debug::debug_context()); + + // Create the event data object. + bool caught_exception = false; + Handle<Object> exec_state = MakeExecutionState(&caught_exception); + Handle<Object> event_data; + if (!caught_exception) { + event_data = MakeBreakEvent(exec_state, break_points_hit, + &caught_exception); + } + // Bail out and don't call debugger if exception. + if (caught_exception) { + return; + } + + // Process debug event + ProcessDebugEvent(v8::Break, event_data, auto_continue); +} + + +void Debugger::OnBeforeCompile(Handle<Script> script) { + HandleScope scope; + + // Bail out based on state or if there is no listener for this event + if (Debug::InDebugger()) return; + if (compiling_natives()) return; + if (!EventActive(v8::BeforeCompile)) return; + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter()) return; + + // Create the event data object. + bool caught_exception = false; + Handle<Object> event_data = MakeCompileEvent(script, true, &caught_exception); + // Bail out and don't call debugger if exception. + if (caught_exception) { + return; + } + + // Process debug event + ProcessDebugEvent(v8::BeforeCompile, event_data, false); +} + + +// Handle debugger actions when a new script is compiled. +void Debugger::OnAfterCompile(Handle<Script> script, Handle<JSFunction> fun) { + HandleScope scope; + + // No compile events while compiling natives. + if (compiling_natives()) return; + + // No more to do if not debugging. + if (!IsDebuggerActive()) return; + + // Store whether in debugger before entering debugger. + bool in_debugger = Debug::InDebugger(); + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter()) return; + + // If debugging there might be script break points registered for this + // script. Make sure that these break points are set. + + // Get the function UpdateScriptBreakPoints (defined in debug-delay.js). + Handle<Object> update_script_break_points = + Handle<Object>(Debug::debug_context()->global()->GetProperty( + *Factory::LookupAsciiSymbol("UpdateScriptBreakPoints"))); + if (!update_script_break_points->IsJSFunction()) { + return; + } + ASSERT(update_script_break_points->IsJSFunction()); + + // Wrap the script object in a proper JS object before passing it + // to JavaScript. + Handle<JSValue> wrapper = GetScriptWrapper(script); + + // Call UpdateScriptBreakPoints expect no exceptions. + bool caught_exception = false; + const int argc = 1; + Object** argv[argc] = { reinterpret_cast<Object**>(wrapper.location()) }; + Handle<Object> result = Execution::TryCall( + Handle<JSFunction>::cast(update_script_break_points), + Top::builtins(), argc, argv, + &caught_exception); + if (caught_exception) { + return; + } + // Bail out based on state or if there is no listener for this event + if (in_debugger) return; + if (!Debugger::EventActive(v8::AfterCompile)) return; + + // Create the compile state object. + Handle<Object> event_data = MakeCompileEvent(script, + false, + &caught_exception); + // Bail out and don't call debugger if exception. + if (caught_exception) { + return; + } + // Process debug event + ProcessDebugEvent(v8::AfterCompile, event_data, false); +} + + +void Debugger::OnNewFunction(Handle<JSFunction> function) { + return; + HandleScope scope; + + // Bail out based on state or if there is no listener for this event + if (Debug::InDebugger()) return; + if (compiling_natives()) return; + if (!Debugger::EventActive(v8::NewFunction)) return; + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter()) return; + + // Create the event object. + bool caught_exception = false; + Handle<Object> event_data = MakeNewFunctionEvent(function, &caught_exception); + // Bail out and don't call debugger if exception. + if (caught_exception) { + return; + } + // Process debug event. + ProcessDebugEvent(v8::NewFunction, event_data, false); +} + + +void Debugger::ProcessDebugEvent(v8::DebugEvent event, + Handle<Object> event_data, + bool auto_continue) { + HandleScope scope; + + // Create the execution state. + bool caught_exception = false; + Handle<Object> exec_state = MakeExecutionState(&caught_exception); + if (caught_exception) { + return; + } + // First notify the message handler if any. + if (message_handler_ != NULL) { + NotifyMessageHandler(event, exec_state, event_data, auto_continue); + } + // Notify registered debug event listener. This can be either a C or a + // JavaScript function. + if (!event_listener_.is_null()) { + if (event_listener_->IsProxy()) { + // C debug event listener. + Handle<Proxy> callback_obj(Handle<Proxy>::cast(event_listener_)); + v8::DebugEventCallback callback = + FUNCTION_CAST<v8::DebugEventCallback>(callback_obj->proxy()); + callback(event, + v8::Utils::ToLocal(Handle<JSObject>::cast(exec_state)), + v8::Utils::ToLocal(Handle<JSObject>::cast(event_data)), + v8::Utils::ToLocal(Handle<Object>::cast(event_listener_data_))); + } else { + // JavaScript debug event listener. + ASSERT(event_listener_->IsJSFunction()); + Handle<JSFunction> fun(Handle<JSFunction>::cast(event_listener_)); + + // Invoke the JavaScript debug event listener. + const int argc = 4; + Object** argv[argc] = { Handle<Object>(Smi::FromInt(event)).location(), + exec_state.location(), + event_data.location(), + event_listener_data_.location() }; + Handle<Object> result = Execution::TryCall(fun, Top::global(), + argc, argv, &caught_exception); + if (caught_exception) { + // Silently ignore exceptions from debug event listeners. + } + } + } + + // Clear the mirror cache. + Debug::ClearMirrorCache(); +} + + +void Debugger::UnloadDebugger() { + // Make sure that there are no breakpoints left. + Debug::ClearAllBreakPoints(); + + // Unload the debugger if feasible. + if (!never_unload_debugger_) { + Debug::Unload(); + } + + // Clear the flag indicating that the message handler was recently cleared. + message_handler_cleared_ = false; +} + + +void Debugger::NotifyMessageHandler(v8::DebugEvent event, + Handle<Object> exec_state, + Handle<Object> event_data, + bool auto_continue) { + HandleScope scope; + + if (!Debug::Load()) return; + + // Process the individual events. + bool interactive = false; + switch (event) { + case v8::Break: + interactive = true; // Break event is always interactive + break; + case v8::Exception: + interactive = true; // Exception event is always interactive + break; + case v8::BeforeCompile: + break; + case v8::AfterCompile: + break; + case v8::NewFunction: + break; + default: + UNREACHABLE(); + } + + // Done if not interactive. + if (!interactive) return; + + // Get the DebugCommandProcessor. + v8::Local<v8::Object> api_exec_state = + v8::Utils::ToLocal(Handle<JSObject>::cast(exec_state)); + v8::Local<v8::String> fun_name = + v8::String::New("debugCommandProcessor"); + v8::Local<v8::Function> fun = + v8::Function::Cast(*api_exec_state->Get(fun_name)); + v8::TryCatch try_catch; + v8::Local<v8::Object> cmd_processor = + v8::Object::Cast(*fun->Call(api_exec_state, 0, NULL)); + if (try_catch.HasCaught()) { + PrintLn(try_catch.Exception()); + return; + } + + // Notify the debugger that a debug event has occurred unless auto continue is + // active in which case no event is send. + if (!auto_continue) { + bool success = SendEventMessage(event_data); + if (!success) { + // If failed to notify debugger just continue running. + return; + } + } + + // Process requests from the debugger. + while (true) { + // Wait for new command in the queue. + command_received_->Wait(); + + // The debug command interrupt flag might have been set when the command was + // added. + StackGuard::Continue(DEBUGCOMMAND); + + // Get the command from the queue. + Vector<uint16_t> command = command_queue_.Get(); + Logger::DebugTag("Got request from command queue, in interactive loop."); + if (!Debugger::IsDebuggerActive()) { + return; + } + + // Check if the command is a host dispatch. + if (command[0] == 0) { + if (Debugger::host_dispatch_handler_) { + int32_t dispatch = (command[1] << 16) | command[2]; + Debugger::host_dispatch_handler_(reinterpret_cast<void*>(dispatch), + Debugger::host_dispatch_handler_data_); + } + if (auto_continue && !HasCommands()) { + return; + } + continue; + } + + // Invoke JavaScript to process the debug request. + v8::Local<v8::String> fun_name; + v8::Local<v8::Function> fun; + v8::Local<v8::Value> request; + v8::TryCatch try_catch; + fun_name = v8::String::New("processDebugRequest"); + fun = v8::Function::Cast(*cmd_processor->Get(fun_name)); + request = v8::String::New(reinterpret_cast<uint16_t*>(command.start()), + command.length()); + static const int kArgc = 1; + v8::Handle<Value> argv[kArgc] = { request }; + v8::Local<v8::Value> response_val = fun->Call(cmd_processor, kArgc, argv); + + // Get the response. + v8::Local<v8::String> response; + bool running = false; + if (!try_catch.HasCaught()) { + // Get response string. + if (!response_val->IsUndefined()) { + response = v8::String::Cast(*response_val); + } else { + response = v8::String::New(""); + } + + // Log the JSON request/response. + if (FLAG_trace_debug_json) { + PrintLn(request); + PrintLn(response); + } + + // Get the running state. + fun_name = v8::String::New("isRunning"); + fun = v8::Function::Cast(*cmd_processor->Get(fun_name)); + static const int kArgc = 1; + v8::Handle<Value> argv[kArgc] = { response }; + v8::Local<v8::Value> running_val = fun->Call(cmd_processor, kArgc, argv); + if (!try_catch.HasCaught()) { + running = running_val->ToBoolean()->Value(); + } + } else { + // In case of failure the result text is the exception text. + response = try_catch.Exception()->ToString(); + } + + // Convert text result to C string. + v8::String::Value val(response); + Vector<uint16_t> str(reinterpret_cast<uint16_t*>(*val), + response->Length()); + + // Return the result. + SendMessage(str); + + // Return from debug event processing if either the VM is put into the + // runnning state (through a continue command) or auto continue is active + // and there are no more commands queued. + if (running || (auto_continue && !HasCommands())) { + return; + } + } +} + + +void Debugger::SetEventListener(Handle<Object> callback, + Handle<Object> data) { + HandleScope scope; + + // Clear the global handles for the event listener and the event listener data + // object. + if (!event_listener_.is_null()) { + GlobalHandles::Destroy( + reinterpret_cast<Object**>(event_listener_.location())); + event_listener_ = Handle<Object>(); + } + if (!event_listener_data_.is_null()) { + GlobalHandles::Destroy( + reinterpret_cast<Object**>(event_listener_data_.location())); + event_listener_data_ = Handle<Object>(); + } + + // If there is a new debug event listener register it together with its data + // object. + if (!callback->IsUndefined() && !callback->IsNull()) { + event_listener_ = Handle<Object>::cast(GlobalHandles::Create(*callback)); + if (data.is_null()) { + data = Factory::undefined_value(); + } + event_listener_data_ = Handle<Object>::cast(GlobalHandles::Create(*data)); + } + + // Unload the debugger if event listener cleared. + if (callback->IsUndefined()) { + UnloadDebugger(); + } +} + + +void Debugger::SetMessageHandler(v8::DebugMessageHandler handler, void* data, + bool message_handler_thread) { + ScopedLock with(debugger_access_); + + message_handler_ = handler; + message_handler_data_ = data; + if (handler != NULL) { + if (!message_thread_ && message_handler_thread) { + message_thread_ = new DebugMessageThread(); + message_thread_->Start(); + } + } else { + // Indicate that the message handler was recently cleared. + message_handler_cleared_ = true; + + // Send an empty command to the debugger if in a break to make JavaScript + // run again if the debugger is closed. + if (Debug::InDebugger()) { + ProcessCommand(Vector<const uint16_t>::empty()); + } + } +} + + +void Debugger::SetHostDispatchHandler(v8::DebugHostDispatchHandler handler, + void* data) { + host_dispatch_handler_ = handler; + host_dispatch_handler_data_ = data; +} + + +// Calls the registered debug message handler. This callback is part of the +// public API. Messages are kept internally as Vector<uint16_t> strings, which +// are allocated in various places and deallocated by the calling function +// sometime after this call. +void Debugger::InvokeMessageHandler(Vector<uint16_t> message) { + ScopedLock with(debugger_access_); + + if (message_handler_ != NULL) { + message_handler_(message.start(), message.length(), message_handler_data_); + } +} + + +void Debugger::SendMessage(Vector<uint16_t> message) { + if (message_thread_ == NULL) { + // If there is no message thread just invoke the message handler from the + // V8 thread. + InvokeMessageHandler(message); + } else { + // Put a copy of the message coming from V8 on the queue. The new copy of + // the event string is destroyed by the message thread. + Vector<uint16_t> message_copy = message.Clone(); + Logger::DebugTag("Put message on event message_queue."); + message_queue_.Put(message_copy); + message_received_->Signal(); + } +} + + +bool Debugger::SendEventMessage(Handle<Object> event_data) { + v8::HandleScope scope; + // Call toJSONProtocol on the debug event object. + v8::Local<v8::Object> api_event_data = + v8::Utils::ToLocal(Handle<JSObject>::cast(event_data)); + v8::Local<v8::String> fun_name = v8::String::New("toJSONProtocol"); + v8::Local<v8::Function> fun = + v8::Function::Cast(*api_event_data->Get(fun_name)); + v8::TryCatch try_catch; + v8::Local<v8::Value> json_event = *fun->Call(api_event_data, 0, NULL); + v8::Local<v8::String> json_event_string; + if (!try_catch.HasCaught()) { + if (!json_event->IsUndefined()) { + json_event_string = json_event->ToString(); + if (FLAG_trace_debug_json) { + PrintLn(json_event_string); + } + v8::String::Value val(json_event_string); + Vector<uint16_t> str(reinterpret_cast<uint16_t*>(*val), + json_event_string->Length()); + SendMessage(str); + } else { + SendMessage(Vector<uint16_t>::empty()); + } + } else { + PrintLn(try_catch.Exception()); + return false; + } + return true; +} + + +// Puts a command coming from the public API on the queue. Creates +// a copy of the command string managed by the debugger. Up to this +// point, the command data was managed by the API client. Called +// by the API client thread. This is where the API client hands off +// processing of the command to the DebugMessageThread thread. +// The new copy of the command is destroyed in HandleCommand(). +void Debugger::ProcessCommand(Vector<const uint16_t> command) { + // Make a copy of the command. Need to cast away const for Clone to work. + Vector<uint16_t> command_copy = + Vector<uint16_t>(const_cast<uint16_t*>(command.start()), + command.length()).Clone(); + Logger::DebugTag("Put command on command_queue."); + command_queue_.Put(command_copy); + command_received_->Signal(); + + // Set the debug command break flag to have the command processed. + if (!Debug::InDebugger()) { + StackGuard::DebugCommand(); + } +} + + +bool Debugger::HasCommands() { + return !command_queue_.IsEmpty(); +} + + +void Debugger::ProcessHostDispatch(void* dispatch) { + // Puts a host dispatch comming from the public API on the queue. + uint16_t hack[3]; + hack[0] = 0; + hack[1] = reinterpret_cast<uint32_t>(dispatch) >> 16; + hack[2] = reinterpret_cast<uint32_t>(dispatch) & 0xFFFF; + Logger::DebugTag("Put dispatch on command_queue."); + command_queue_.Put(Vector<uint16_t>(hack, 3).Clone()); + command_received_->Signal(); + + // Set the debug command break flag to have the host dispatch processed. + if (!Debug::InDebugger()) { + StackGuard::DebugCommand(); + } +} + + +bool Debugger::IsDebuggerActive() { + ScopedLock with(debugger_access_); + + return message_handler_ != NULL || !event_listener_.is_null(); +} + + +Handle<Object> Debugger::Call(Handle<JSFunction> fun, + Handle<Object> data, + bool* pending_exception) { + // When calling functions in the debugger prevent it from beeing unloaded. + Debugger::never_unload_debugger_ = true; + + // Enter the debugger. + EnterDebugger debugger; + if (debugger.FailedToEnter() || !debugger.HasJavaScriptFrames()) { + return Factory::undefined_value(); + } + + // Create the execution state. + bool caught_exception = false; + Handle<Object> exec_state = MakeExecutionState(&caught_exception); + if (caught_exception) { + return Factory::undefined_value(); + } + + static const int kArgc = 2; + Object** argv[kArgc] = { exec_state.location(), data.location() }; + Handle<Object> result = Execution::Call(fun, Factory::undefined_value(), + kArgc, argv, pending_exception); + return result; +} + + +bool Debugger::StartAgent(const char* name, int port) { + if (Socket::Setup()) { + agent_ = new DebuggerAgent(name, port); + agent_->Start(); + return true; + } + + return false; +} + + +void Debugger::StopAgent() { + if (agent_ != NULL) { + agent_->Shutdown(); + agent_->Join(); + delete agent_; + agent_ = NULL; + } +} + + +void Debugger::TearDown() { + if (message_thread_ != NULL) { + message_thread_->Stop(); + delete message_thread_; + message_thread_ = NULL; + } +} + + +void DebugMessageThread::Run() { + // Sends debug events to an installed debugger message callback. + while (keep_running_) { + // Wait and Get are paired so that semaphore count equals queue length. + Debugger::message_received_->Wait(); + Logger::DebugTag("Get message from event message_queue."); + Vector<uint16_t> message = Debugger::message_queue_.Get(); + if (message.length() > 0) { + Debugger::InvokeMessageHandler(message); + } + } +} + + +void DebugMessageThread::Stop() { + keep_running_ = false; + Debugger::SendMessage(Vector<uint16_t>(NULL, 0)); + Join(); +} + + +MessageQueue::MessageQueue(int size) : start_(0), end_(0), size_(size) { + messages_ = NewArray<Vector<uint16_t> >(size); +} + + +MessageQueue::~MessageQueue() { + DeleteArray(messages_); +} + + +Vector<uint16_t> MessageQueue::Get() { + ASSERT(!IsEmpty()); + int result = start_; + start_ = (start_ + 1) % size_; + return messages_[result]; +} + + +void MessageQueue::Put(const Vector<uint16_t>& message) { + if ((end_ + 1) % size_ == start_) { + Expand(); + } + messages_[end_] = message; + end_ = (end_ + 1) % size_; +} + + +void MessageQueue::Expand() { + MessageQueue new_queue(size_ * 2); + while (!IsEmpty()) { + new_queue.Put(Get()); + } + Vector<uint16_t>* array_to_free = messages_; + *this = new_queue; + new_queue.messages_ = array_to_free; + // Automatic destructor called on new_queue, freeing array_to_free. +} + + +LockingMessageQueue::LockingMessageQueue(int size) : queue_(size) { + lock_ = OS::CreateMutex(); +} + + +LockingMessageQueue::~LockingMessageQueue() { + delete lock_; +} + + +bool LockingMessageQueue::IsEmpty() const { + ScopedLock sl(lock_); + return queue_.IsEmpty(); +} + + +Vector<uint16_t> LockingMessageQueue::Get() { + ScopedLock sl(lock_); + Vector<uint16_t> result = queue_.Get(); + Logger::DebugEvent("Get", result); + return result; +} + + +void LockingMessageQueue::Put(const Vector<uint16_t>& message) { + ScopedLock sl(lock_); + queue_.Put(message); + Logger::DebugEvent("Put", message); +} + + +void LockingMessageQueue::Clear() { + ScopedLock sl(lock_); + queue_.Clear(); +} + + +} } // namespace v8::internal |