AppleThreadPlanStepThroughObjCTrampoline.cpp revision 314564
1//===-- AppleThreadPlanStepThroughObjCTrampoline.cpp 2//--------------------------*- C++ -*-===// 3// 4// The LLVM Compiler Infrastructure 5// 6// This file is distributed under the University of Illinois Open Source 7// License. See LICENSE.TXT for details. 8// 9//===----------------------------------------------------------------------===// 10 11// C Includes 12// C++ Includes 13// Other libraries and framework includes 14// Project includes 15#include "AppleThreadPlanStepThroughObjCTrampoline.h" 16#include "AppleObjCTrampolineHandler.h" 17#include "lldb/Core/Log.h" 18#include "lldb/Expression/DiagnosticManager.h" 19#include "lldb/Expression/FunctionCaller.h" 20#include "lldb/Expression/UtilityFunction.h" 21#include "lldb/Target/ExecutionContext.h" 22#include "lldb/Target/ObjCLanguageRuntime.h" 23#include "lldb/Target/Process.h" 24#include "lldb/Target/Thread.h" 25#include "lldb/Target/ThreadPlanRunToAddress.h" 26#include "lldb/Target/ThreadPlanStepOut.h" 27 28using namespace lldb; 29using namespace lldb_private; 30 31//---------------------------------------------------------------------- 32// ThreadPlanStepThroughObjCTrampoline constructor 33//---------------------------------------------------------------------- 34AppleThreadPlanStepThroughObjCTrampoline:: 35 AppleThreadPlanStepThroughObjCTrampoline( 36 Thread &thread, AppleObjCTrampolineHandler *trampoline_handler, 37 ValueList &input_values, lldb::addr_t isa_addr, lldb::addr_t sel_addr, 38 bool stop_others) 39 : ThreadPlan(ThreadPlan::eKindGeneric, 40 "MacOSX Step through ObjC Trampoline", thread, eVoteNoOpinion, 41 eVoteNoOpinion), 42 m_trampoline_handler(trampoline_handler), 43 m_args_addr(LLDB_INVALID_ADDRESS), m_input_values(input_values), 44 m_isa_addr(isa_addr), m_sel_addr(sel_addr), m_impl_function(NULL), 45 m_stop_others(stop_others) {} 46 47//---------------------------------------------------------------------- 48// Destructor 49//---------------------------------------------------------------------- 50AppleThreadPlanStepThroughObjCTrampoline:: 51 ~AppleThreadPlanStepThroughObjCTrampoline() {} 52 53void AppleThreadPlanStepThroughObjCTrampoline::DidPush() { 54 // Setting up the memory space for the called function text might require 55 // allocations, 56 // i.e. a nested function call. This needs to be done as a PreResumeAction. 57 m_thread.GetProcess()->AddPreResumeAction(PreResumeInitializeFunctionCaller, 58 (void *)this); 59} 60 61bool AppleThreadPlanStepThroughObjCTrampoline::InitializeFunctionCaller() { 62 if (!m_func_sp) { 63 DiagnosticManager diagnostics; 64 m_args_addr = 65 m_trampoline_handler->SetupDispatchFunction(m_thread, m_input_values); 66 67 if (m_args_addr == LLDB_INVALID_ADDRESS) { 68 return false; 69 } 70 m_impl_function = 71 m_trampoline_handler->GetLookupImplementationFunctionCaller(); 72 ExecutionContext exc_ctx; 73 EvaluateExpressionOptions options; 74 options.SetUnwindOnError(true); 75 options.SetIgnoreBreakpoints(true); 76 options.SetStopOthers(m_stop_others); 77 m_thread.CalculateExecutionContext(exc_ctx); 78 m_func_sp = m_impl_function->GetThreadPlanToCallFunction( 79 exc_ctx, m_args_addr, options, diagnostics); 80 m_func_sp->SetOkayToDiscard(true); 81 m_thread.QueueThreadPlan(m_func_sp, false); 82 } 83 return true; 84} 85 86bool AppleThreadPlanStepThroughObjCTrampoline:: 87 PreResumeInitializeFunctionCaller(void *void_myself) { 88 AppleThreadPlanStepThroughObjCTrampoline *myself = 89 static_cast<AppleThreadPlanStepThroughObjCTrampoline *>(void_myself); 90 return myself->InitializeFunctionCaller(); 91} 92 93void AppleThreadPlanStepThroughObjCTrampoline::GetDescription( 94 Stream *s, lldb::DescriptionLevel level) { 95 if (level == lldb::eDescriptionLevelBrief) 96 s->Printf("Step through ObjC trampoline"); 97 else { 98 s->Printf("Stepping to implementation of ObjC method - obj: 0x%llx, isa: " 99 "0x%" PRIx64 ", sel: 0x%" PRIx64, 100 m_input_values.GetValueAtIndex(0)->GetScalar().ULongLong(), 101 m_isa_addr, m_sel_addr); 102 } 103} 104 105bool AppleThreadPlanStepThroughObjCTrampoline::ValidatePlan(Stream *error) { 106 return true; 107} 108 109bool AppleThreadPlanStepThroughObjCTrampoline::DoPlanExplainsStop( 110 Event *event_ptr) { 111 // If we get asked to explain the stop it will be because something went 112 // wrong (like the implementation for selector function crashed... We're 113 // going 114 // to figure out what to do about that, so we do explain the stop. 115 return true; 116} 117 118lldb::StateType AppleThreadPlanStepThroughObjCTrampoline::GetPlanRunState() { 119 return eStateRunning; 120} 121 122bool AppleThreadPlanStepThroughObjCTrampoline::ShouldStop(Event *event_ptr) { 123 // First stage: we are still handling the "call a function to get the target 124 // of the dispatch" 125 if (m_func_sp) { 126 if (!m_func_sp->IsPlanComplete()) { 127 return false; 128 } else { 129 if (!m_func_sp->PlanSucceeded()) { 130 SetPlanComplete(false); 131 return true; 132 } 133 m_func_sp.reset(); 134 } 135 } 136 137 // Second stage, if all went well with the function calling, then fetch the 138 // target address, and 139 // queue up a "run to that address" plan. 140 if (!m_run_to_sp) { 141 Value target_addr_value; 142 ExecutionContext exc_ctx; 143 m_thread.CalculateExecutionContext(exc_ctx); 144 m_impl_function->FetchFunctionResults(exc_ctx, m_args_addr, 145 target_addr_value); 146 m_impl_function->DeallocateFunctionResults(exc_ctx, m_args_addr); 147 lldb::addr_t target_addr = target_addr_value.GetScalar().ULongLong(); 148 Address target_so_addr; 149 target_so_addr.SetOpcodeLoadAddress(target_addr, exc_ctx.GetTargetPtr()); 150 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP)); 151 if (target_addr == 0) { 152 if (log) 153 log->Printf("Got target implementation of 0x0, stopping."); 154 SetPlanComplete(); 155 return true; 156 } 157 if (m_trampoline_handler->AddrIsMsgForward(target_addr)) { 158 if (log) 159 log->Printf( 160 "Implementation lookup returned msgForward function: 0x%" PRIx64 161 ", stopping.", 162 target_addr); 163 164 SymbolContext sc = m_thread.GetStackFrameAtIndex(0)->GetSymbolContext( 165 eSymbolContextEverything); 166 const bool abort_other_plans = false; 167 const bool first_insn = true; 168 const uint32_t frame_idx = 0; 169 m_run_to_sp = m_thread.QueueThreadPlanForStepOutNoShouldStop( 170 abort_other_plans, &sc, first_insn, m_stop_others, eVoteNoOpinion, 171 eVoteNoOpinion, frame_idx); 172 m_run_to_sp->SetPrivate(true); 173 return false; 174 } 175 176 if (log) 177 log->Printf("Running to ObjC method implementation: 0x%" PRIx64, 178 target_addr); 179 180 ObjCLanguageRuntime *objc_runtime = 181 GetThread().GetProcess()->GetObjCLanguageRuntime(); 182 assert(objc_runtime != NULL); 183 objc_runtime->AddToMethodCache(m_isa_addr, m_sel_addr, target_addr); 184 if (log) 185 log->Printf("Adding {isa-addr=0x%" PRIx64 ", sel-addr=0x%" PRIx64 186 "} = addr=0x%" PRIx64 " to cache.", 187 m_isa_addr, m_sel_addr, target_addr); 188 189 // Extract the target address from the value: 190 191 m_run_to_sp.reset( 192 new ThreadPlanRunToAddress(m_thread, target_so_addr, m_stop_others)); 193 m_thread.QueueThreadPlan(m_run_to_sp, false); 194 m_run_to_sp->SetPrivate(true); 195 return false; 196 } else if (m_thread.IsThreadPlanDone(m_run_to_sp.get())) { 197 // Third stage, work the run to target plan. 198 SetPlanComplete(); 199 return true; 200 } 201 return false; 202} 203 204// The base class MischiefManaged does some cleanup - so you have to call it 205// in your MischiefManaged derived class. 206bool AppleThreadPlanStepThroughObjCTrampoline::MischiefManaged() { 207 if (IsPlanComplete()) 208 return true; 209 else 210 return false; 211} 212 213bool AppleThreadPlanStepThroughObjCTrampoline::WillStop() { return true; } 214