UnwindPlanSP
FuncUnwinders::GetUnwindPlanArchitectureDefaultAtFunctionEntry (Thread& thread)
{
// Lock the mutex to ensure we can always give out the most appropriate
// information. We want to make sure if someone requests an unwind
// plan, that they get one and don't run into a race condition where one
// thread has started to create the unwind plan and has put it into
// the auto_ptr member variable, and have another thread enter this function
// and return the partially filled pointer contained in the auto_ptr.
// We also want to make sure that we lock out other unwind plans from
// being accessed until this one is done creating itself in case someone
// had some code like:
// UnwindPlan *best_unwind_plan = ...GetUnwindPlanAtCallSite (...)
// if (best_unwind_plan == NULL)
// best_unwind_plan = GetUnwindPlanAtNonCallSite (...)
Mutex::Locker locker (m_mutex);
if (m_tried_unwind_arch_default_at_func_entry == false && m_unwind_plan_arch_default_at_func_entry_sp.get() == NULL)
{
m_tried_unwind_arch_default_at_func_entry = true;
Address current_pc;
ProcessSP process_sp (thread.CalculateProcess());
if (process_sp)
{
ABI *abi = process_sp->GetABI().get();
if (abi)
{
m_unwind_plan_arch_default_at_func_entry_sp.reset (new UnwindPlan (lldb::eRegisterKindGeneric));
if (m_unwind_plan_arch_default_at_func_entry_sp)
abi->CreateFunctionEntryUnwindPlan(*m_unwind_plan_arch_default_at_func_entry_sp);
}
}
}
return m_unwind_plan_arch_default_sp;
}
UnwindPlanSP
FuncUnwinders::GetUnwindPlanArchitectureDefaultAtFunctionEntry (Thread& thread)
{
if (m_unwind_plan_arch_default_at_func_entry_sp.get() || m_tried_unwind_arch_default_at_func_entry)
return m_unwind_plan_arch_default_at_func_entry_sp;
std::lock_guard<std::recursive_mutex> guard(m_mutex);
m_tried_unwind_arch_default_at_func_entry = true;
Address current_pc;
ProcessSP process_sp (thread.CalculateProcess());
if (process_sp)
{
ABI *abi = process_sp->GetABI().get();
if (abi)
{
m_unwind_plan_arch_default_at_func_entry_sp.reset (new UnwindPlan (lldb::eRegisterKindGeneric));
if (!abi->CreateFunctionEntryUnwindPlan(*m_unwind_plan_arch_default_at_func_entry_sp))
{
m_unwind_plan_arch_default_at_func_entry_sp.reset();
}
}
}
return m_unwind_plan_arch_default_at_func_entry_sp;
}
StopInfoSP
StopInfoMachException::CreateStopReasonWithMachException
(
Thread &thread,
uint32_t exc_type,
uint32_t exc_data_count,
uint64_t exc_code,
uint64_t exc_sub_code,
uint64_t exc_sub_sub_code,
bool pc_already_adjusted,
bool adjust_pc_if_needed
)
{
if (exc_type != 0)
{
uint32_t pc_decrement = 0;
ExecutionContext exe_ctx (thread.shared_from_this());
Target *target = exe_ctx.GetTargetPtr();
const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
switch (exc_type)
{
case 1: // EXC_BAD_ACCESS
break;
case 2: // EXC_BAD_INSTRUCTION
switch (cpu)
{
case llvm::Triple::ppc:
case llvm::Triple::ppc64:
switch (exc_code)
{
case 1: // EXC_PPC_INVALID_SYSCALL
case 2: // EXC_PPC_UNIPL_INST
case 3: // EXC_PPC_PRIVINST
case 4: // EXC_PPC_PRIVREG
break;
case 5: // EXC_PPC_TRACE
return StopInfo::CreateStopReasonToTrace (thread);
case 6: // EXC_PPC_PERFMON
break;
}
break;
default:
break;
}
break;
case 3: // EXC_ARITHMETIC
case 4: // EXC_EMULATION
break;
case 5: // EXC_SOFTWARE
if (exc_code == 0x10003) // EXC_SOFT_SIGNAL
return StopInfo::CreateStopReasonWithSignal (thread, exc_sub_code);
break;
case 6: // EXC_BREAKPOINT
{
bool is_software_breakpoint = false;
bool is_trace_if_software_breakpoint_missing = false;
switch (cpu)
{
case llvm::Triple::x86:
case llvm::Triple::x86_64:
if (exc_code == 1) // EXC_I386_SGL
{
if (!exc_sub_code)
return StopInfo::CreateStopReasonToTrace(thread);
// It's a watchpoint, then.
// The exc_sub_code indicates the data break address.
lldb::WatchpointSP wp_sp;
if (target)
wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
if (wp_sp && wp_sp->IsEnabled())
{
// Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
// Set the hardware index if that's the case.
if (exc_data_count >=3)
wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
}
}
else if (exc_code == 2 || // EXC_I386_BPT
exc_code == 3) // EXC_I386_BPTFLT
{
// KDP returns EXC_I386_BPTFLT for trace breakpoints
if (exc_code == 3)
is_trace_if_software_breakpoint_missing = true;
is_software_breakpoint = true;
if (!pc_already_adjusted)
pc_decrement = 1;
}
break;
case llvm::Triple::ppc:
case llvm::Triple::ppc64:
is_software_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT
break;
case llvm::Triple::arm:
if (exc_code == 0x102)
{
// It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
// data break address from our watchpoint list.
lldb::WatchpointSP wp_sp;
if (target)
wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
if (wp_sp && wp_sp->IsEnabled())
{
// Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
// Set the hardware index if that's the case.
if (exc_data_count >=3)
wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
}
// EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
if (thread.GetTemporaryResumeState() == eStateStepping)
return StopInfo::CreateStopReasonToTrace(thread);
}
else if (exc_code == 1)
{
is_software_breakpoint = true;
is_trace_if_software_breakpoint_missing = true;
}
break;
default:
break;
}
if (is_software_breakpoint)
{
RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;
ProcessSP process_sp (thread.CalculateProcess());
lldb::BreakpointSiteSP bp_site_sp;
if (process_sp)
bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
if (bp_site_sp && bp_site_sp->IsEnabled())
{
// Update the PC if we were asked to do so, but only do
// so if we find a breakpoint that we know about cause
// this could be a trap instruction in the code
if (pc_decrement > 0 && adjust_pc_if_needed)
reg_ctx_sp->SetPC (pc);
// If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
// we can just report no reason. We don't need to worry about stepping over the breakpoint here, that
// will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
if (bp_site_sp->ValidForThisThread (&thread))
return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
else
return StopInfoSP();
}
// Don't call this a trace if we weren't single stepping this thread.
if (is_trace_if_software_breakpoint_missing && thread.GetTemporaryResumeState() == eStateStepping)
{
return StopInfo::CreateStopReasonToTrace (thread);
}
}
}
break;
case 7: // EXC_SYSCALL
case 8: // EXC_MACH_SYSCALL
case 9: // EXC_RPC_ALERT
case 10: // EXC_CRASH
break;
}
return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
}
return StopInfoSP();
}
ThreadPlanSP
ObjCTrampolineHandler::GetStepThroughDispatchPlan (Thread &thread, bool stop_others)
{
ThreadPlanSP ret_plan_sp;
lldb::addr_t curr_pc = thread.GetRegisterContext()->GetPC();
MsgsendMap::iterator pos;
pos = m_msgSend_map.find (curr_pc);
if (pos != m_msgSend_map.end())
{
Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP);
const DispatchFunction *this_dispatch = &g_dispatch_functions[(*pos).second];
lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0);
Process *process = thread.CalculateProcess();
const ABI *abi = process->GetABI();
if (abi == NULL)
return ret_plan_sp;
Target *target = thread.CalculateTarget();
// FIXME: Since neither the value nor the Clang QualType know their ASTContext,
// we have to make sure the type we put in our value list comes from the same ASTContext
// the ABI will use to get the argument values. THis is the bottom-most frame's module.
ClangASTContext *clang_ast_context = target->GetScratchClangASTContext();
ValueList argument_values;
Value input_value;
void *clang_void_ptr_type = clang_ast_context->GetVoidPtrType(false);
input_value.SetValueType (Value::eValueTypeScalar);
input_value.SetContext (Value::eContextTypeOpaqueClangQualType, clang_void_ptr_type);
int obj_index;
int sel_index;
// If this is a struct return dispatch, then the first argument is the
// return struct pointer, and the object is the second, and the selector is the third.
// Otherwise the object is the first and the selector the second.
if (this_dispatch->stret_return)
{
obj_index = 1;
sel_index = 2;
argument_values.PushValue(input_value);
argument_values.PushValue(input_value);
argument_values.PushValue(input_value);
}
else
{
obj_index = 0;
sel_index = 1;
argument_values.PushValue(input_value);
argument_values.PushValue(input_value);
}
bool success = abi->GetArgumentValues (thread, argument_values);
if (!success)
return ret_plan_sp;
// Okay, the first value here is the object, we actually want the class of that object.
// For now we're just going with the ISA.
// FIXME: This should really be the return value of [object class] to properly handle KVO interposition.
Value isa_value(*(argument_values.GetValueAtIndex(obj_index)));
// This is a little cheesy, but since object->isa is the first field,
// making the object value a load address value and resolving it will get
// the pointer sized data pointed to by that value...
ExecutionContext exec_ctx;
thread.Calculate (exec_ctx);
isa_value.SetValueType(Value::eValueTypeLoadAddress);
isa_value.ResolveValue(&exec_ctx, clang_ast_context->getASTContext());
if (this_dispatch->fixedup == DispatchFunction::eFixUpFixed)
{
// For the FixedUp method the Selector is actually a pointer to a
// structure, the second field of which is the selector number.
Value *sel_value = argument_values.GetValueAtIndex(sel_index);
sel_value->GetScalar() += process->GetAddressByteSize();
sel_value->SetValueType(Value::eValueTypeLoadAddress);
sel_value->ResolveValue(&exec_ctx, clang_ast_context->getASTContext());
}
else if (this_dispatch->fixedup == DispatchFunction::eFixUpToFix)
{
// FIXME: If the method dispatch is not "fixed up" then the selector is actually a
// pointer to the string name of the selector. We need to look that up...
// For now I'm going to punt on that and just return no plan.
if (log)
log->Printf ("Punting on stepping into un-fixed-up method dispatch.");
return ret_plan_sp;
}
// FIXME: If this is a dispatch to the super-class, we need to get the super-class from
// the class, and disaptch to that instead.
// But for now I just punt and return no plan.
if (this_dispatch->is_super)
{
if (log)
log->Printf ("Punting on stepping into super method dispatch.");
return ret_plan_sp;
}
ValueList dispatch_values;
dispatch_values.PushValue (isa_value);
dispatch_values.PushValue(*(argument_values.GetValueAtIndex(sel_index)));
if (log)
{
log->Printf("Resolving method call for class - 0x%llx and selector - 0x%llx",
dispatch_values.GetValueAtIndex(0)->GetScalar().ULongLong(),
dispatch_values.GetValueAtIndex(1)->GetScalar().ULongLong());
}
lldb::addr_t impl_addr = LookupInCache (dispatch_values.GetValueAtIndex(0)->GetScalar().ULongLong(),
dispatch_values.GetValueAtIndex(1)->GetScalar().ULongLong());
if (impl_addr == LLDB_INVALID_ADDRESS)
{
Address resolve_address(NULL, this_dispatch->stret_return ? m_impl_stret_fn_addr : m_impl_fn_addr);
StreamString errors;
{
// Scope for mutex locker:
Mutex::Locker locker(m_impl_function_mutex);
if (!m_impl_function.get())
{
m_impl_function.reset(new ClangFunction(process->GetTargetTriple().GetCString(),
clang_ast_context,
clang_void_ptr_type,
resolve_address,
dispatch_values));
unsigned num_errors = m_impl_function->CompileFunction(errors);
if (num_errors)
{
if (log)
log->Printf ("Error compiling function: \"%s\".", errors.GetData());
return ret_plan_sp;
}
errors.Clear();
if (!m_impl_function->WriteFunctionWrapper(exec_ctx, errors))
{
if (log)
log->Printf ("Error Inserting function: \"%s\".", errors.GetData());
return ret_plan_sp;
}
}
}
errors.Clear();
// Now write down the argument values for this call.
lldb::addr_t args_addr = LLDB_INVALID_ADDRESS;
if (!m_impl_function->WriteFunctionArguments (exec_ctx, args_addr, resolve_address, dispatch_values, errors))
return ret_plan_sp;
ret_plan_sp.reset (new ThreadPlanStepThroughObjCTrampoline (thread, this, args_addr,
argument_values.GetValueAtIndex(0)->GetScalar().ULongLong(),
dispatch_values.GetValueAtIndex(0)->GetScalar().ULongLong(),
dispatch_values.GetValueAtIndex(1)->GetScalar().ULongLong(),
stop_others));
}
else
{
if (log)
log->Printf ("Found implementation address in cache: 0x%llx", impl_addr);
ret_plan_sp.reset (new ThreadPlanRunToAddress (thread, impl_addr, stop_others));
}
}
return ret_plan_sp;
}
StopInfoSP
StopInfoMachException::CreateStopReasonWithMachException
(
Thread &thread,
uint32_t exc_type,
uint32_t exc_data_count,
uint64_t exc_code,
uint64_t exc_sub_code,
uint64_t exc_sub_sub_code,
bool pc_already_adjusted,
bool adjust_pc_if_needed
)
{
if (exc_type != 0)
{
uint32_t pc_decrement = 0;
ExecutionContext exe_ctx (thread.shared_from_this());
Target *target = exe_ctx.GetTargetPtr();
const llvm::Triple::ArchType cpu = target ? target->GetArchitecture().GetMachine() : llvm::Triple::UnknownArch;
switch (exc_type)
{
case 1: // EXC_BAD_ACCESS
break;
case 2: // EXC_BAD_INSTRUCTION
switch (cpu)
{
case llvm::Triple::ppc:
case llvm::Triple::ppc64:
switch (exc_code)
{
case 1: // EXC_PPC_INVALID_SYSCALL
case 2: // EXC_PPC_UNIPL_INST
case 3: // EXC_PPC_PRIVINST
case 4: // EXC_PPC_PRIVREG
break;
case 5: // EXC_PPC_TRACE
return StopInfo::CreateStopReasonToTrace (thread);
case 6: // EXC_PPC_PERFMON
break;
}
break;
default:
break;
}
break;
case 3: // EXC_ARITHMETIC
case 4: // EXC_EMULATION
break;
case 5: // EXC_SOFTWARE
if (exc_code == 0x10003) // EXC_SOFT_SIGNAL
{
if (exc_sub_code == 5)
{
// On MacOSX, a SIGTRAP can signify that a process has called
// exec, so we should check with our dynamic loader to verify.
ProcessSP process_sp (thread.GetProcess());
if (process_sp)
{
DynamicLoader *dynamic_loader = process_sp->GetDynamicLoader();
if (dynamic_loader && dynamic_loader->ProcessDidExec())
{
// The program was re-exec'ed
return StopInfo::CreateStopReasonWithExec (thread);
}
// if (!process_did_exec)
// {
// // We have a SIGTRAP, make sure we didn't exec by checking
// // for the PC being at "_dyld_start"...
// lldb::StackFrameSP frame_sp (thread.GetStackFrameAtIndex(0));
// if (frame_sp)
// {
// const Symbol *symbol = frame_sp->GetSymbolContext(eSymbolContextSymbol).symbol;
// if (symbol)
// {
// if (symbol->GetName() == ConstString("_dyld_start"))
// process_did_exec = true;
// }
// }
// }
}
}
return StopInfo::CreateStopReasonWithSignal (thread, exc_sub_code);
}
break;
case 6: // EXC_BREAKPOINT
{
bool is_actual_breakpoint = false;
bool is_trace_if_actual_breakpoint_missing = false;
switch (cpu)
{
case llvm::Triple::x86:
case llvm::Triple::x86_64:
if (exc_code == 1) // EXC_I386_SGL
{
if (!exc_sub_code)
{
// This looks like a plain trap.
// Have to check if there is a breakpoint here as well. When you single-step onto a trap,
// the single step stops you not to trap. Since we also do that check below, let's just use
// that logic.
is_actual_breakpoint = true;
is_trace_if_actual_breakpoint_missing = true;
}
else
{
// It's a watchpoint, then.
// The exc_sub_code indicates the data break address.
lldb::WatchpointSP wp_sp;
if (target)
wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
if (wp_sp && wp_sp->IsEnabled())
{
// Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
// Set the hardware index if that's the case.
if (exc_data_count >=3)
wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
}
}
}
else if (exc_code == 2 || // EXC_I386_BPT
exc_code == 3) // EXC_I386_BPTFLT
{
// KDP returns EXC_I386_BPTFLT for trace breakpoints
if (exc_code == 3)
is_trace_if_actual_breakpoint_missing = true;
is_actual_breakpoint = true;
if (!pc_already_adjusted)
pc_decrement = 1;
}
break;
case llvm::Triple::ppc:
case llvm::Triple::ppc64:
is_actual_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT
break;
case llvm::Triple::arm:
if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
{
// It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
// data break address from our watchpoint list.
lldb::WatchpointSP wp_sp;
if (target)
wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
if (wp_sp && wp_sp->IsEnabled())
{
// Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
// Set the hardware index if that's the case.
if (exc_data_count >=3)
wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
}
else
{
is_actual_breakpoint = true;
is_trace_if_actual_breakpoint_missing = true;
}
}
else if (exc_code == 1) // EXC_ARM_BREAKPOINT
{
is_actual_breakpoint = true;
is_trace_if_actual_breakpoint_missing = true;
}
else if (exc_code == 0) // FIXME not EXC_ARM_BREAKPOINT but a kernel is currently returning this so accept it as indicating a breakpoint until the kernel is fixed
{
is_actual_breakpoint = true;
is_trace_if_actual_breakpoint_missing = true;
}
break;
case llvm::Triple::aarch64:
{
if (exc_code == 1 && exc_sub_code == 0) // EXC_ARM_BREAKPOINT
{
// This is hit when we single instruction step aka MDSCR_EL1 SS bit 0 is set
return StopInfo::CreateStopReasonToTrace(thread);
}
if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
{
// It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
// data break address from our watchpoint list.
lldb::WatchpointSP wp_sp;
if (target)
wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
if (wp_sp && wp_sp->IsEnabled())
{
// Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
// Set the hardware index if that's the case.
if (exc_data_count >= 3)
wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
}
// EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
if (thread.GetTemporaryResumeState() == eStateStepping)
return StopInfo::CreateStopReasonToTrace(thread);
}
// It looks like exc_sub_code has the 4 bytes of the instruction that triggered the
// exception, i.e. our breakpoint opcode
is_actual_breakpoint = exc_code == 1;
break;
}
default:
break;
}
if (is_actual_breakpoint)
{
RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;
ProcessSP process_sp (thread.CalculateProcess());
lldb::BreakpointSiteSP bp_site_sp;
if (process_sp)
bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
if (bp_site_sp && bp_site_sp->IsEnabled())
{
// Update the PC if we were asked to do so, but only do
// so if we find a breakpoint that we know about cause
// this could be a trap instruction in the code
if (pc_decrement > 0 && adjust_pc_if_needed)
reg_ctx_sp->SetPC (pc);
// If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
// we can just report no reason. We don't need to worry about stepping over the breakpoint here, that
// will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
// If we have an operating system plug-in, we might have set a thread specific breakpoint using the
// operating system thread ID, so we can't make any assumptions about the thread ID so we must always
// report the breakpoint regardless of the thread.
if (bp_site_sp->ValidForThisThread (&thread) || thread.GetProcess()->GetOperatingSystem () != NULL)
return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
else
return StopInfoSP();
}
// Don't call this a trace if we weren't single stepping this thread.
if (is_trace_if_actual_breakpoint_missing && thread.GetTemporaryResumeState() == eStateStepping)
{
return StopInfo::CreateStopReasonToTrace (thread);
}
}
}
break;
case 7: // EXC_SYSCALL
case 8: // EXC_MACH_SYSCALL
case 9: // EXC_RPC_ALERT
case 10: // EXC_CRASH
break;
}
return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
}
return StopInfoSP();
}
