1 //===-- LLVMUserExpression.cpp ----------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // C Includes 11 // C++ Includes 12 13 // Project includes 14 #include "lldb/Expression/LLVMUserExpression.h" 15 #include "lldb/Core/ConstString.h" 16 #include "lldb/Core/Log.h" 17 #include "lldb/Core/Module.h" 18 #include "lldb/Core/StreamFile.h" 19 #include "lldb/Core/StreamString.h" 20 #include "lldb/Core/ValueObjectConstResult.h" 21 #include "lldb/Expression/ExpressionSourceCode.h" 22 #include "lldb/Expression/IRExecutionUnit.h" 23 #include "lldb/Expression/IRInterpreter.h" 24 #include "lldb/Expression/Materializer.h" 25 #include "lldb/Host/HostInfo.h" 26 #include "lldb/Symbol/Block.h" 27 #include "lldb/Symbol/ClangASTContext.h" 28 #include "lldb/Symbol/Function.h" 29 #include "lldb/Symbol/ObjectFile.h" 30 #include "lldb/Symbol/SymbolVendor.h" 31 #include "lldb/Symbol/Type.h" 32 #include "lldb/Symbol/ClangExternalASTSourceCommon.h" 33 #include "lldb/Symbol/VariableList.h" 34 #include "lldb/Target/ExecutionContext.h" 35 #include "lldb/Target/Process.h" 36 #include "lldb/Target/StackFrame.h" 37 #include "lldb/Target/Target.h" 38 #include "lldb/Target/ThreadPlan.h" 39 #include "lldb/Target/ThreadPlanCallUserExpression.h" 40 41 using namespace lldb_private; 42 43 LLVMUserExpression::LLVMUserExpression(ExecutionContextScope &exe_scope, 44 const char *expr, 45 const char *expr_prefix, 46 lldb::LanguageType language, 47 ResultType desired_type, 48 const EvaluateExpressionOptions &options) 49 : UserExpression(exe_scope, expr, expr_prefix, language, desired_type, options), 50 m_stack_frame_bottom(LLDB_INVALID_ADDRESS), 51 m_stack_frame_top(LLDB_INVALID_ADDRESS), 52 m_transformed_text(), 53 m_execution_unit_sp(), 54 m_materializer_ap(), 55 m_jit_module_wp(), 56 m_enforce_valid_object(true), 57 m_in_cplusplus_method(false), 58 m_in_objectivec_method(false), 59 m_in_static_method(false), 60 m_needs_object_ptr(false), 61 m_const_object(false), 62 m_target(NULL), 63 m_can_interpret(false), 64 m_materialized_address(LLDB_INVALID_ADDRESS) 65 { 66 } 67 68 LLVMUserExpression::~LLVMUserExpression() 69 { 70 if (m_target) 71 { 72 lldb::ModuleSP jit_module_sp(m_jit_module_wp.lock()); 73 if (jit_module_sp) 74 m_target->GetImages().Remove(jit_module_sp); 75 } 76 } 77 78 lldb::ExpressionResults 79 LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, const EvaluateExpressionOptions &options, 80 lldb::UserExpressionSP &shared_ptr_to_me, lldb::ExpressionVariableSP &result) 81 { 82 // The expression log is quite verbose, and if you're just tracking the execution of the 83 // expression, it's quite convenient to have these logs come out with the STEP log as well. 84 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP)); 85 86 if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret) 87 { 88 lldb::addr_t struct_address = LLDB_INVALID_ADDRESS; 89 90 if (!PrepareToExecuteJITExpression(error_stream, exe_ctx, struct_address)) 91 { 92 error_stream.Printf("Errored out in %s, couldn't PrepareToExecuteJITExpression", __FUNCTION__); 93 return lldb::eExpressionSetupError; 94 } 95 96 lldb::addr_t function_stack_bottom = LLDB_INVALID_ADDRESS; 97 lldb::addr_t function_stack_top = LLDB_INVALID_ADDRESS; 98 99 if (m_can_interpret) 100 { 101 llvm::Module *module = m_execution_unit_sp->GetModule(); 102 llvm::Function *function = m_execution_unit_sp->GetFunction(); 103 104 if (!module || !function) 105 { 106 error_stream.Printf("Supposed to interpret, but nothing is there"); 107 return lldb::eExpressionSetupError; 108 } 109 110 Error interpreter_error; 111 112 std::vector<lldb::addr_t> args; 113 114 if (!AddInitialArguments(exe_ctx, args, error_stream)) 115 { 116 error_stream.Printf("Errored out in %s, couldn't AddInitialArguments", __FUNCTION__); 117 return lldb::eExpressionSetupError; 118 } 119 120 args.push_back(struct_address); 121 122 function_stack_bottom = m_stack_frame_bottom; 123 function_stack_top = m_stack_frame_top; 124 125 IRInterpreter::Interpret(*module, *function, args, *m_execution_unit_sp.get(), interpreter_error, 126 function_stack_bottom, function_stack_top, exe_ctx); 127 128 if (!interpreter_error.Success()) 129 { 130 error_stream.Printf("Supposed to interpret, but failed: %s", interpreter_error.AsCString()); 131 return lldb::eExpressionDiscarded; 132 } 133 } 134 else 135 { 136 if (!exe_ctx.HasThreadScope()) 137 { 138 error_stream.Printf("UserExpression::Execute called with no thread selected."); 139 return lldb::eExpressionSetupError; 140 } 141 142 Address wrapper_address(m_jit_start_addr); 143 144 std::vector<lldb::addr_t> args; 145 146 if (!AddInitialArguments(exe_ctx, args, error_stream)) 147 { 148 error_stream.Printf("Errored out in %s, couldn't AddInitialArguments", __FUNCTION__); 149 return lldb::eExpressionSetupError; 150 } 151 152 args.push_back(struct_address); 153 154 lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression(exe_ctx.GetThreadRef(), wrapper_address, 155 args, options, shared_ptr_to_me)); 156 157 if (!call_plan_sp || !call_plan_sp->ValidatePlan(&error_stream)) 158 return lldb::eExpressionSetupError; 159 160 ThreadPlanCallUserExpression *user_expression_plan = 161 static_cast<ThreadPlanCallUserExpression *>(call_plan_sp.get()); 162 163 lldb::addr_t function_stack_pointer = user_expression_plan->GetFunctionStackPointer(); 164 165 function_stack_bottom = function_stack_pointer - HostInfo::GetPageSize(); 166 function_stack_top = function_stack_pointer; 167 168 if (log) 169 log->Printf("-- [UserExpression::Execute] Execution of expression begins --"); 170 171 if (exe_ctx.GetProcessPtr()) 172 exe_ctx.GetProcessPtr()->SetRunningUserExpression(true); 173 174 lldb::ExpressionResults execution_result = 175 exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, error_stream); 176 177 if (exe_ctx.GetProcessPtr()) 178 exe_ctx.GetProcessPtr()->SetRunningUserExpression(false); 179 180 if (log) 181 log->Printf("-- [UserExpression::Execute] Execution of expression completed --"); 182 183 if (execution_result == lldb::eExpressionInterrupted || execution_result == lldb::eExpressionHitBreakpoint) 184 { 185 const char *error_desc = NULL; 186 187 if (call_plan_sp) 188 { 189 lldb::StopInfoSP real_stop_info_sp = call_plan_sp->GetRealStopInfo(); 190 if (real_stop_info_sp) 191 error_desc = real_stop_info_sp->GetDescription(); 192 } 193 if (error_desc) 194 error_stream.Printf("Execution was interrupted, reason: %s.", error_desc); 195 else 196 error_stream.PutCString("Execution was interrupted."); 197 198 if ((execution_result == lldb::eExpressionInterrupted && options.DoesUnwindOnError()) || 199 (execution_result == lldb::eExpressionHitBreakpoint && options.DoesIgnoreBreakpoints())) 200 error_stream.PutCString( 201 "\nThe process has been returned to the state before expression evaluation."); 202 else 203 { 204 if (execution_result == lldb::eExpressionHitBreakpoint) 205 user_expression_plan->TransferExpressionOwnership(); 206 error_stream.PutCString( 207 "\nThe process has been left at the point where it was interrupted, " 208 "use \"thread return -x\" to return to the state before expression evaluation."); 209 } 210 211 return execution_result; 212 } 213 else if (execution_result == lldb::eExpressionStoppedForDebug) 214 { 215 error_stream.PutCString( 216 "Execution was halted at the first instruction of the expression " 217 "function because \"debug\" was requested.\n" 218 "Use \"thread return -x\" to return to the state before expression evaluation."); 219 return execution_result; 220 } 221 else if (execution_result != lldb::eExpressionCompleted) 222 { 223 error_stream.Printf("Couldn't execute function; result was %s\n", 224 Process::ExecutionResultAsCString(execution_result)); 225 return execution_result; 226 } 227 } 228 229 if (FinalizeJITExecution(error_stream, exe_ctx, result, function_stack_bottom, function_stack_top)) 230 { 231 return lldb::eExpressionCompleted; 232 } 233 else 234 { 235 return lldb::eExpressionResultUnavailable; 236 } 237 } 238 else 239 { 240 error_stream.Printf("Expression can't be run, because there is no JIT compiled function"); 241 return lldb::eExpressionSetupError; 242 } 243 } 244 245 bool 246 LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext &exe_ctx, 247 lldb::ExpressionVariableSP &result, lldb::addr_t function_stack_bottom, 248 lldb::addr_t function_stack_top) 249 { 250 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); 251 252 if (log) 253 log->Printf("-- [UserExpression::FinalizeJITExecution] Dematerializing after execution --"); 254 255 if (!m_dematerializer_sp) 256 { 257 error_stream.Printf("Couldn't apply expression side effects : no dematerializer is present"); 258 return false; 259 } 260 261 Error dematerialize_error; 262 263 m_dematerializer_sp->Dematerialize(dematerialize_error, function_stack_bottom, function_stack_top); 264 265 if (!dematerialize_error.Success()) 266 { 267 error_stream.Printf("Couldn't apply expression side effects : %s\n", 268 dematerialize_error.AsCString("unknown error")); 269 return false; 270 } 271 272 result = GetResultAfterDematerialization(exe_ctx.GetBestExecutionContextScope()); 273 274 if (result) 275 result->TransferAddress(); 276 277 m_dematerializer_sp.reset(); 278 279 return true; 280 } 281 282 bool 283 LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, ExecutionContext &exe_ctx, 284 lldb::addr_t &struct_address) 285 { 286 lldb::TargetSP target; 287 lldb::ProcessSP process; 288 lldb::StackFrameSP frame; 289 290 if (!LockAndCheckContext(exe_ctx, target, process, frame)) 291 { 292 error_stream.Printf("The context has changed before we could JIT the expression!\n"); 293 return false; 294 } 295 296 if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret) 297 { 298 if (m_materialized_address == LLDB_INVALID_ADDRESS) 299 { 300 Error alloc_error; 301 302 IRMemoryMap::AllocationPolicy policy = 303 m_can_interpret ? IRMemoryMap::eAllocationPolicyHostOnly : IRMemoryMap::eAllocationPolicyMirror; 304 305 const bool zero_memory = false; 306 307 m_materialized_address = m_execution_unit_sp->Malloc(m_materializer_ap->GetStructByteSize(), 308 m_materializer_ap->GetStructAlignment(), 309 lldb::ePermissionsReadable | lldb::ePermissionsWritable, 310 policy, 311 zero_memory, 312 alloc_error); 313 314 if (!alloc_error.Success()) 315 { 316 error_stream.Printf("Couldn't allocate space for materialized struct: %s\n", alloc_error.AsCString()); 317 return false; 318 } 319 } 320 321 struct_address = m_materialized_address; 322 323 if (m_can_interpret && m_stack_frame_bottom == LLDB_INVALID_ADDRESS) 324 { 325 Error alloc_error; 326 327 const size_t stack_frame_size = 512 * 1024; 328 329 const bool zero_memory = false; 330 331 m_stack_frame_bottom = m_execution_unit_sp->Malloc(stack_frame_size, 332 8, 333 lldb::ePermissionsReadable | lldb::ePermissionsWritable, 334 IRMemoryMap::eAllocationPolicyHostOnly, 335 zero_memory, 336 alloc_error); 337 338 m_stack_frame_top = m_stack_frame_bottom + stack_frame_size; 339 340 if (!alloc_error.Success()) 341 { 342 error_stream.Printf("Couldn't allocate space for the stack frame: %s\n", alloc_error.AsCString()); 343 return false; 344 } 345 } 346 347 Error materialize_error; 348 349 m_dematerializer_sp = 350 m_materializer_ap->Materialize(frame, *m_execution_unit_sp, struct_address, materialize_error); 351 352 if (!materialize_error.Success()) 353 { 354 error_stream.Printf("Couldn't materialize: %s\n", materialize_error.AsCString()); 355 return false; 356 } 357 } 358 return true; 359 } 360 361 lldb::ModuleSP 362 LLVMUserExpression::GetJITModule() 363 { 364 if (m_execution_unit_sp) 365 return m_execution_unit_sp->GetJITModule(); 366 return lldb::ModuleSP(); 367 } 368