blob: 6378fb1f69b1dc2de93dfb11ffc4f1bc62504cd5 [file] [log] [blame]
// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "include/dart_tools_api.h"
#include "vm/kernel_isolate.h"
#include "vm/object.h"
#include "vm/port.h"
#include "vm/scopes.h"
#include "vm/service_event.h"
#include "vm/simulator.h"
#include "vm/stack_frame.h"
#include "vm/stack_trace.h"
DECLARE_FLAG(bool, verbose_debug);
// 'Trace Debugger' TD_Print.
#if defined(_MSC_VER)
#define TD_Print(format, ...) \
if (FLAG_verbose_debug) Log::Current()->Print(format, __VA_ARGS__)
#define TD_Print(format, ...) \
if (FLAG_verbose_debug) Log::Current()->Print(format, ##__VA_ARGS__)
namespace dart {
class CodeBreakpoint;
class Isolate;
class JSONArray;
class JSONStream;
class ObjectPointerVisitor;
class BreakpointLocation;
class StackFrame;
// A user-defined breakpoint, which either fires once, for a particular closure,
// or always. The API's notion of a breakpoint corresponds to this object.
class Breakpoint {
Breakpoint(intptr_t id, BreakpointLocation* bpt_location)
: id_(id),
is_synthetic_async_(false) {}
intptr_t id() const { return id_; }
Breakpoint* next() const { return next_; }
void set_next(Breakpoint* n) { next_ = n; }
BreakpointLocation* bpt_location() const { return bpt_location_; }
void set_bpt_location(BreakpointLocation* new_bpt_location);
bool IsRepeated() const { return kind_ == kRepeated; }
bool IsSingleShot() const { return kind_ == kSingleShot; }
bool IsPerClosure() const { return kind_ == kPerClosure; }
InstancePtr closure() const { return closure_; }
void SetIsRepeated() {
ASSERT(kind_ == kNone);
kind_ = kRepeated;
void SetIsSingleShot() {
ASSERT(kind_ == kNone);
kind_ = kSingleShot;
void SetIsPerClosure(const Instance& closure) {
ASSERT(kind_ == kNone);
kind_ = kPerClosure;
closure_ = closure.ptr();
// Mark that this breakpoint is a result of a step OverAwait request.
void set_is_synthetic_async(bool is_synthetic_async) {
is_synthetic_async_ = is_synthetic_async;
bool is_synthetic_async() const { return is_synthetic_async_; }
void PrintJSON(JSONStream* stream);
void VisitObjectPointers(ObjectPointerVisitor* visitor);
enum ConditionKind {
intptr_t id_;
ConditionKind kind_;
Breakpoint* next_;
InstancePtr closure_;
BreakpointLocation* bpt_location_;
bool is_synthetic_async_;
friend class BreakpointLocation;
// BreakpointLocation represents a collection of breakpoint conditions at the
// same token position in Dart source. There may be more than one CodeBreakpoint
// object per BreakpointLocation.
// An unresolved breakpoint is one where the underlying code has not
// been compiled yet. Since the code has not been compiled, we don't know
// the definitive source location yet. The requested source location may
// change when the underlying code gets compiled.
// A latent breakpoint represents a breakpoint location in Dart source
// that is not loaded in the VM when the breakpoint is requested.
// When a script with matching url is loaded, a latent breakpoint
// becomes an unresolved breakpoint.
class BreakpointLocation {
// Create a new unresolved breakpoint.
BreakpointLocation(const Script& script,
TokenPosition token_pos,
TokenPosition end_token_pos,
intptr_t requested_line_number,
intptr_t requested_column_number);
// Create a new latent breakpoint.
BreakpointLocation(const String& url,
intptr_t requested_line_number,
intptr_t requested_column_number);
FunctionPtr function() const { return function_; }
TokenPosition token_pos() const { return token_pos_; }
TokenPosition end_token_pos() const { return end_token_pos_; }
ScriptPtr script() const { return script_; }
StringPtr url() const { return url_; }
intptr_t requested_line_number() const { return requested_line_number_; }
intptr_t requested_column_number() const { return requested_column_number_; }
void GetCodeLocation(Script* script, TokenPosition* token_pos) const;
Breakpoint* AddRepeated(Debugger* dbg);
Breakpoint* AddSingleShot(Debugger* dbg);
Breakpoint* AddPerClosure(Debugger* dbg,
const Instance& closure,
bool for_over_await);
bool AnyEnabled() const;
bool IsResolved() const { return code_token_pos_.IsReal(); }
bool IsLatent() const { return !token_pos_.IsReal(); }
void VisitObjectPointers(ObjectPointerVisitor* visitor);
void SetResolved(const Function& func, TokenPosition token_pos);
BreakpointLocation* next() const { return this->next_; }
void set_next(BreakpointLocation* value) { next_ = value; }
void AddBreakpoint(Breakpoint* bpt, Debugger* dbg);
Breakpoint* breakpoints() const { return this->conditions_; }
void set_breakpoints(Breakpoint* head) { this->conditions_ = head; }
// Finds the breakpoint we hit at |location|.
Breakpoint* FindHitBreakpoint(ActivationFrame* top_frame);
ScriptPtr script_;
StringPtr url_;
TokenPosition token_pos_;
TokenPosition end_token_pos_;
BreakpointLocation* next_;
Breakpoint* conditions_;
intptr_t requested_line_number_;
intptr_t requested_column_number_;
// Valid for resolved breakpoints:
FunctionPtr function_;
TokenPosition code_token_pos_;
friend class Debugger;
// CodeBreakpoint represents a location in compiled code.
// There may be more than one CodeBreakpoint for one BreakpointLocation,
// e.g. when a function gets compiled as a regular function and as a closure.
class CodeBreakpoint {
CodeBreakpoint(const Code& code,
TokenPosition token_pos,
uword pc,
UntaggedPcDescriptors::Kind kind);
FunctionPtr function() const;
uword pc() const { return pc_; }
TokenPosition token_pos() const { return token_pos_; }
ScriptPtr SourceCode();
StringPtr SourceUrl();
intptr_t LineNumber();
void Enable();
void Disable();
bool IsEnabled() const { return is_enabled_; }
CodePtr OrigStubAddress() const;
void VisitObjectPointers(ObjectPointerVisitor* visitor);
BreakpointLocation* bpt_location() const { return bpt_location_; }
void set_bpt_location(BreakpointLocation* value) { bpt_location_ = value; }
void set_next(CodeBreakpoint* value) { next_ = value; }
CodeBreakpoint* next() const { return this->next_; }
void PatchCode();
void RestoreCode();
CodePtr code_;
TokenPosition token_pos_;
uword pc_;
intptr_t line_number_;
bool is_enabled_;
BreakpointLocation* bpt_location_;
CodeBreakpoint* next_;
UntaggedPcDescriptors::Kind breakpoint_kind_;
CodePtr saved_value_;
friend class Debugger;
// ActivationFrame represents one dart function activation frame
// on the call stack.
class ActivationFrame : public ZoneAllocated {
enum Kind {
ActivationFrame(uword pc,
uword fp,
uword sp,
const Code& code,
const Array& deopt_frame,
intptr_t deopt_frame_offset,
Kind kind = kRegular);
ActivationFrame(uword pc, const Code& code);
explicit ActivationFrame(Kind kind);
explicit ActivationFrame(const Closure& async_activation);
uword pc() const { return pc_; }
uword fp() const { return fp_; }
uword sp() const { return sp_; }
uword GetCallerSp() const { return fp() + (kCallerSpSlotFromFp * kWordSize); }
const Function& function() const {
return function_;
const Code& code() const {
return code_;
enum Relation {
Relation CompareTo(uword other_fp) const;
StringPtr QualifiedFunctionName();
StringPtr SourceUrl();
ScriptPtr SourceScript();
LibraryPtr Library();
TokenPosition TokenPos();
intptr_t LineNumber();
intptr_t ColumnNumber();
// Returns true if this frame is for a function that is visible
// to the user and can be debugged.
bool IsDebuggable() const;
// Returns true if it is possible to rewind the debugger to this frame.
bool IsRewindable() const;
// The context level of a frame is the context level at the
// PC/token index of the frame. It determines the depth of the context
// chain that belongs to the function of this activation frame.
intptr_t ContextLevel();
const char* ToCString();
intptr_t NumLocalVariables();
void VariableAt(intptr_t i,
String* name,
TokenPosition* declaration_token_pos,
TokenPosition* visible_start_token_pos,
TokenPosition* visible_end_token_pos,
Object* value);
ArrayPtr GetLocalVariables();
ObjectPtr GetParameter(intptr_t index);
ClosurePtr GetClosure();
ObjectPtr GetReceiver();
const Context& GetSavedCurrentContext();
ObjectPtr GetAsyncOperation();
TypeArgumentsPtr BuildParameters(
const GrowableObjectArray& param_names,
const GrowableObjectArray& param_values,
const GrowableObjectArray& type_params_names);
ObjectPtr EvaluateCompiledExpression(const ExternalTypedData& kernel_data,
const Array& arguments,
const Array& type_definitions,
const TypeArguments& type_arguments);
void PrintToJSONObject(JSONObject* jsobj);
// Get Closure that await'ed this async frame.
ObjectPtr GetAsyncAwaiter(CallerClosureFinder* caller_closure_finder);
bool HandlesException(const Instance& exc_obj);
void PrintToJSONObjectRegular(JSONObject* jsobj);
void PrintToJSONObjectAsyncCausal(JSONObject* jsobj);
void PrintToJSONObjectAsyncSuspensionMarker(JSONObject* jsobj);
void PrintContextMismatchError(intptr_t ctx_slot,
intptr_t frame_ctx_level,
intptr_t var_ctx_level);
void PrintDescriptorsError(const char* message);
intptr_t TryIndex();
intptr_t DeoptId();
void GetPcDescriptors();
void GetVarDescriptors();
void GetDescIndices();
ObjectPtr GetAsyncContextVariable(const String& name);
// Get the current continuation index in the :await_jump_var pulled from the
// context.
intptr_t GetAwaitJumpVariable();
void ExtractTokenPositionFromAsyncClosure();
bool IsAsyncMachinery() const;
static const char* KindToCString(Kind kind) {
switch (kind) {
case kRegular:
return "Regular";
case kAsyncCausal:
return "AsyncCausal";
case kAsyncSuspensionMarker:
return "AsyncSuspensionMarker";
case kAsyncActivation:
return "AsyncActivation";
return "";
ObjectPtr GetStackVar(VariableIndex var_index);
ObjectPtr GetRelativeContextVar(intptr_t ctxt_level,
intptr_t slot_index,
intptr_t frame_ctx_level);
ObjectPtr GetContextVar(intptr_t ctxt_level, intptr_t slot_index);
uword pc_;
uword fp_;
uword sp_;
// The anchor of the context chain for this function.
Context& ctx_;
Code& code_;
Function& function_;
bool live_frame_; // Is this frame a live frame?
bool token_pos_initialized_;
TokenPosition token_pos_;
intptr_t try_index_;
intptr_t deopt_id_;
intptr_t line_number_;
intptr_t column_number_;
intptr_t context_level_;
// Some frames are deoptimized into a side array in order to inspect them.
const Array& deopt_frame_;
const intptr_t deopt_frame_offset_;
Kind kind_;
bool vars_initialized_;
LocalVarDescriptors& var_descriptors_;
ZoneGrowableArray<intptr_t> desc_indices_;
PcDescriptors& pc_desc_;
friend class Debugger;
friend class DebuggerStackTrace;
// Array of function activations on the call stack.
class DebuggerStackTrace : public ZoneAllocated {
explicit DebuggerStackTrace(int capacity) : trace_(capacity) {}
intptr_t Length() const { return trace_.length(); }
ActivationFrame* FrameAt(int i) const { return trace_[i]; }
ActivationFrame* GetHandlerFrame(const Instance& exc_obj) const;
static DebuggerStackTrace* CollectAwaiterReturn();
static DebuggerStackTrace* Collect();
// Returns a debugger stack trace corresponding to a dart.core.StackTrace.
// Frames corresponding to invisible functions are omitted. It is not valid
// to query local variables in the returned stack.
static DebuggerStackTrace* From(const class StackTrace& ex_trace);
void AddActivation(ActivationFrame* frame);
void AddMarker(ActivationFrame::Kind marker);
void AddAsyncCausalFrame(uword pc, const Code& code);
void AppendCodeFrames(Thread* thread,
Isolate* isolate,
Zone* zone,
StackFrame* frame,
Code* code,
Code* inlined_code,
Array* deopt_frame);
static DebuggerStackTrace* CollectAsyncCausal();
static DebuggerStackTrace* CollectAsyncLazy();
ZoneGrowableArray<ActivationFrame*> trace_;
friend class Debugger;
// On which exceptions to pause.
typedef enum {
kNoPauseOnExceptions = 1,
} Dart_ExceptionPauseInfo;
class Debugger {
enum ResumeAction {
explicit Debugger(Isolate* isolate);
void NotifyIsolateCreated();
void Shutdown();
void NotifyCompilation(const Function& func);
void NotifyDoneLoading();
// Set breakpoint at closest location to function entry.
Breakpoint* SetBreakpointAtEntry(const Function& target_function,
bool single_shot);
Breakpoint* SetBreakpointAtActivation(const Instance& closure,
bool for_over_await);
Breakpoint* BreakpointAtActivation(const Instance& closure);
// TODO(turnidge): script_url may no longer be specific enough.
Breakpoint* SetBreakpointAtLine(const String& script_url,
intptr_t line_number);
Breakpoint* SetBreakpointAtLineCol(const String& script_url,
intptr_t line_number,
intptr_t column_number);
// Sets synthetic breakpoint at async_op to step over the synthetic part of
// the stack trace.
Breakpoint* SetBreakpointAtAsyncOp(const Function& async_op);
BreakpointLocation* BreakpointLocationAtLineCol(const String& script_url,
intptr_t line_number,
intptr_t column_number);
void RemoveBreakpoint(intptr_t bp_id);
Breakpoint* GetBreakpointById(intptr_t id);
void MaybeAsyncStepInto(const Closure& async_op);
void AsyncStepInto(const Closure& async_op);
void Continue();
bool SetResumeAction(ResumeAction action,
intptr_t frame_index = 1,
const char** error = NULL);
bool IsStepping() const { return resume_action_ != kContinue; }
bool IsSingleStepping() const { return resume_action_ == kStepInto; }
bool IsPaused() const { return pause_event_ != NULL; }
bool ignore_breakpoints() const { return ignore_breakpoints_; }
void set_ignore_breakpoints(bool ignore_breakpoints) {
ignore_breakpoints_ = ignore_breakpoints;
// Put the isolate into single stepping mode when Dart code next runs.
// This is used by the vm service to allow the user to step while
// paused at isolate start.
void EnterSingleStepMode();
// Indicates why the debugger is currently paused. If the debugger
// is not paused, this returns NULL. Note that the debugger can be
// paused for breakpoints, isolate interruption, and (sometimes)
// exceptions.
const ServiceEvent* PauseEvent() const { return pause_event_; }
void SetExceptionPauseInfo(Dart_ExceptionPauseInfo pause_info);
Dart_ExceptionPauseInfo GetExceptionPauseInfo() const;
void VisitObjectPointers(ObjectPointerVisitor* visitor);
// Returns true if there is at least one breakpoint set in func or code.
// Checks for both user-defined and internal temporary breakpoints.
// This may be called from different threads, therefore do not use the,
// debugger's zone.
bool HasBreakpoint(const Function& func, Zone* zone);
bool HasBreakpoint(const Code& code);
// Returns true if the call at address pc is patched to point to
// a debugger stub.
bool HasActiveBreakpoint(uword pc);
// Returns a stack trace with frames corresponding to invisible functions
// omitted. CurrentStackTrace always returns a new trace on the current stack.
// The trace returned by StackTrace may have been cached; it is suitable for
// use when stepping, but otherwise may be out of sync with the current stack.
DebuggerStackTrace* StackTrace();
DebuggerStackTrace* AsyncCausalStackTrace();
DebuggerStackTrace* AwaiterStackTrace();
// Pause execution for a breakpoint. Called from generated code.
ErrorPtr PauseBreakpoint();
// Pause execution due to stepping. Called from generated code.
ErrorPtr PauseStepping();
// Pause execution due to isolate interrupt.
ErrorPtr PauseInterrupted();
// Pause after a reload request.
ErrorPtr PausePostRequest();
// Pause execution due to an uncaught exception.
void PauseException(const Instance& exc);
// Pause execution due to a call to the debugger() function from
// Dart.
void PauseDeveloper(const String& msg);
CodePtr GetPatchedStubAddress(uword breakpoint_address);
void PrintBreakpointsToJSONArray(JSONArray* jsarr) const;
void PrintSettingsToJSONObject(JSONObject* jsobj) const;
static bool IsDebuggable(const Function& func);
// IsolateGroupDebugger::
static bool IsDebugging(Thread* thread, const Function& func);
intptr_t limitBreakpointId() { return next_id_; }
// Callback to the debugger to continue frame rewind, post-deoptimization.
void RewindPostDeopt();
ErrorPtr PauseRequest(ServiceEvent::EventKind kind);
// Will return false if we are not at an await.
bool SetupStepOverAsyncSuspension(const char** error);
bool NeedsIsolateEvents();
bool NeedsDebugEvents();
void SendBreakpointEvent(ServiceEvent::EventKind kind, Breakpoint* bpt);
// IsolateGroupDebugger::
void FindCompiledFunctions(const Script& script,
TokenPosition start_pos,
TokenPosition end_pos,
GrowableObjectArray* code_function_list);
// IsolateGroupDebugger::
bool FindBestFit(const Script& script,
TokenPosition token_pos,
TokenPosition last_token_pos,
Function* best_fit);
// IsolateGroupDebugger::
void DeoptimizeWorld();
void NotifySingleStepping(bool value) const;
BreakpointLocation* SetCodeBreakpoints(const Script& script,
TokenPosition token_pos,
TokenPosition last_token_pos,
intptr_t requested_line,
intptr_t requested_column,
TokenPosition exact_token_pos,
const GrowableObjectArray& functions);
BreakpointLocation* SetBreakpoint(const Script& script,
TokenPosition token_pos,
TokenPosition last_token_pos,
intptr_t requested_line,
intptr_t requested_column,
const Function& function);
bool RemoveBreakpointFromTheList(intptr_t bp_id, BreakpointLocation** list);
Breakpoint* GetBreakpointByIdInTheList(intptr_t id, BreakpointLocation* list);
void RemoveUnlinkedCodeBreakpoints();
void UnlinkCodeBreakpoints(BreakpointLocation* bpt_location);
BreakpointLocation* GetLatentBreakpoint(const String& url,
intptr_t line,
intptr_t column);
void RegisterBreakpointLocation(BreakpointLocation* bpt);
void RegisterCodeBreakpoint(CodeBreakpoint* bpt);
BreakpointLocation* GetBreakpointLocation(
const Script& script,
TokenPosition token_pos,
intptr_t requested_line,
intptr_t requested_column,
TokenPosition code_token_pos = TokenPosition::kNoSource);
void MakeCodeBreakpointAt(const Function& func, BreakpointLocation* bpt);
// Returns NULL if no breakpoint exists for the given address.
CodeBreakpoint* GetCodeBreakpoint(uword breakpoint_address);
void SyncBreakpointLocation(BreakpointLocation* loc);
void PrintBreakpointsListToJSONArray(BreakpointLocation* sbpt,
JSONArray* jsarr) const;
void SignalPausedEvent(ActivationFrame* top_frame, Breakpoint* bpt);
intptr_t nextId() { return next_id_++; }
bool ShouldPauseOnException(DebuggerStackTrace* stack_trace,
const Instance& exc);
// Handles any events which pause vm execution. Breakpoints,
// interrupts, etc.
void Pause(ServiceEvent* event);
void HandleSteppingRequest(DebuggerStackTrace* stack_trace,
bool skip_next_step = false);
void CacheStackTraces(DebuggerStackTrace* stack_trace,
DebuggerStackTrace* async_causal_stack_trace,
DebuggerStackTrace* awaiter_stack_trace);
void ClearCachedStackTraces();
void RewindToFrame(intptr_t frame_index);
void RewindToUnoptimizedFrame(StackFrame* frame, const Code& code);
void RewindToOptimizedFrame(StackFrame* frame,
const Code& code,
intptr_t post_deopt_frame_index);
void ResetSteppingFramePointers();
bool SteppedForSyntheticAsyncBreakpoint() const;
void CleanupSyntheticAsyncBreakpoint();
void RememberTopFrameAwaiter();
void SetAsyncSteppingFramePointer(DebuggerStackTrace* stack_trace);
void SetSyncSteppingFramePointer(DebuggerStackTrace* stack_trace);
Isolate* isolate_;
// ID number generator.
intptr_t next_id_;
BreakpointLocation* latent_locations_;
BreakpointLocation* breakpoint_locations_;
CodeBreakpoint* code_breakpoints_;
// Tells debugger what to do when resuming execution after a breakpoint.
ResumeAction resume_action_;
intptr_t resume_frame_index_;
intptr_t post_deopt_frame_index_;
// Do not call back to breakpoint handler if this flag is set.
// Effectively this means ignoring breakpoints. Set when Dart code may
// be run as a side effect of getting values of fields.
bool ignore_breakpoints_;
// Indicates why the debugger is currently paused. If the debugger
// is not paused, this is NULL. Note that the debugger can be
// paused for breakpoints, isolate interruption, and (sometimes)
// exceptions.
ServiceEvent* pause_event_;
// Current stack trace. Valid only while IsPaused().
DebuggerStackTrace* stack_trace_;
DebuggerStackTrace* async_causal_stack_trace_;
DebuggerStackTrace* awaiter_stack_trace_;
// When stepping through code, only pause the program if the top
// frame corresponds to this fp value, or if the top frame is
// lower on the stack.
uword stepping_fp_;
// When stepping through code, do not stop more than once in the same
// token position range.
uword last_stepping_fp_;
TokenPosition last_stepping_pos_;
// Used to track the current async/async* function.
uword async_stepping_fp_;
ObjectPtr top_frame_awaiter_;
// If we step while at a breakpoint, we would hit the same pc twice.
// We use this field to let us skip the next single-step after a
// breakpoint.
bool skip_next_step_;
bool needs_breakpoint_cleanup_;
// We keep this breakpoint alive until after the debugger does the step over
// async continuation machinery so that we can report that we've stopped
// at the breakpoint.
Breakpoint* synthetic_async_breakpoint_;
Dart_ExceptionPauseInfo exc_pause_info_;
friend class Isolate;
friend class BreakpointLocation;
class DisableBreakpointsScope : public ValueObject {
DisableBreakpointsScope(Debugger* debugger, bool disable)
: debugger_(debugger) {
ASSERT(debugger_ != NULL);
initial_state_ = debugger_->ignore_breakpoints();
~DisableBreakpointsScope() {
Debugger* debugger_;
bool initial_state_;
} // namespace dart