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 (!AddArguments(exe_ctx, args, struct_address, error_stream)) 115 { 116 error_stream.Printf("Errored out in %s, couldn't AddArguments", __FUNCTION__); 117 return lldb::eExpressionSetupError; 118 } 119 120 function_stack_bottom = m_stack_frame_bottom; 121 function_stack_top = m_stack_frame_top; 122 123 IRInterpreter::Interpret(*module, *function, args, *m_execution_unit_sp.get(), interpreter_error, 124 function_stack_bottom, function_stack_top, exe_ctx); 125 126 if (!interpreter_error.Success()) 127 { 128 error_stream.Printf("Supposed to interpret, but failed: %s", interpreter_error.AsCString()); 129 return lldb::eExpressionDiscarded; 130 } 131 } 132 else 133 { 134 if (!exe_ctx.HasThreadScope()) 135 { 136 error_stream.Printf("UserExpression::Execute called with no thread selected."); 137 return lldb::eExpressionSetupError; 138 } 139 140 Address wrapper_address(m_jit_start_addr); 141 142 std::vector<lldb::addr_t> args; 143 144 if (!AddArguments(exe_ctx, args, struct_address, error_stream)) 145 { 146 error_stream.Printf("Errored out in %s, couldn't AddArguments", __FUNCTION__); 147 return lldb::eExpressionSetupError; 148 } 149 150 lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression(exe_ctx.GetThreadRef(), wrapper_address, 151 args, options, shared_ptr_to_me)); 152 153 if (!call_plan_sp || !call_plan_sp->ValidatePlan(&error_stream)) 154 return lldb::eExpressionSetupError; 155 156 ThreadPlanCallUserExpression *user_expression_plan = 157 static_cast<ThreadPlanCallUserExpression *>(call_plan_sp.get()); 158 159 lldb::addr_t function_stack_pointer = user_expression_plan->GetFunctionStackPointer(); 160 161 function_stack_bottom = function_stack_pointer - HostInfo::GetPageSize(); 162 function_stack_top = function_stack_pointer; 163 164 if (log) 165 log->Printf("-- [UserExpression::Execute] Execution of expression begins --"); 166 167 if (exe_ctx.GetProcessPtr()) 168 exe_ctx.GetProcessPtr()->SetRunningUserExpression(true); 169 170 lldb::ExpressionResults execution_result = 171 exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, error_stream); 172 173 if (exe_ctx.GetProcessPtr()) 174 exe_ctx.GetProcessPtr()->SetRunningUserExpression(false); 175 176 if (log) 177 log->Printf("-- [UserExpression::Execute] Execution of expression completed --"); 178 179 if (execution_result == lldb::eExpressionInterrupted || execution_result == lldb::eExpressionHitBreakpoint) 180 { 181 const char *error_desc = NULL; 182 183 if (call_plan_sp) 184 { 185 lldb::StopInfoSP real_stop_info_sp = call_plan_sp->GetRealStopInfo(); 186 if (real_stop_info_sp) 187 error_desc = real_stop_info_sp->GetDescription(); 188 } 189 if (error_desc) 190 error_stream.Printf("Execution was interrupted, reason: %s.", error_desc); 191 else 192 error_stream.PutCString("Execution was interrupted."); 193 194 if ((execution_result == lldb::eExpressionInterrupted && options.DoesUnwindOnError()) || 195 (execution_result == lldb::eExpressionHitBreakpoint && options.DoesIgnoreBreakpoints())) 196 error_stream.PutCString( 197 "\nThe process has been returned to the state before expression evaluation."); 198 else 199 { 200 if (execution_result == lldb::eExpressionHitBreakpoint) 201 user_expression_plan->TransferExpressionOwnership(); 202 error_stream.PutCString( 203 "\nThe process has been left at the point where it was interrupted, " 204 "use \"thread return -x\" to return to the state before expression evaluation."); 205 } 206 207 return execution_result; 208 } 209 else if (execution_result == lldb::eExpressionStoppedForDebug) 210 { 211 error_stream.PutCString( 212 "Execution was halted at the first instruction of the expression " 213 "function because \"debug\" was requested.\n" 214 "Use \"thread return -x\" to return to the state before expression evaluation."); 215 return execution_result; 216 } 217 else if (execution_result != lldb::eExpressionCompleted) 218 { 219 error_stream.Printf("Couldn't execute function; result was %s\n", 220 Process::ExecutionResultAsCString(execution_result)); 221 return execution_result; 222 } 223 } 224 225 if (FinalizeJITExecution(error_stream, exe_ctx, result, function_stack_bottom, function_stack_top)) 226 { 227 return lldb::eExpressionCompleted; 228 } 229 else 230 { 231 return lldb::eExpressionResultUnavailable; 232 } 233 } 234 else 235 { 236 error_stream.Printf("Expression can't be run, because there is no JIT compiled function"); 237 return lldb::eExpressionSetupError; 238 } 239 } 240 241 bool 242 LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext &exe_ctx, 243 lldb::ExpressionVariableSP &result, lldb::addr_t function_stack_bottom, 244 lldb::addr_t function_stack_top) 245 { 246 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); 247 248 if (log) 249 log->Printf("-- [UserExpression::FinalizeJITExecution] Dematerializing after execution --"); 250 251 if (!m_dematerializer_sp) 252 { 253 error_stream.Printf("Couldn't apply expression side effects : no dematerializer is present"); 254 return false; 255 } 256 257 Error dematerialize_error; 258 259 m_dematerializer_sp->Dematerialize(dematerialize_error, function_stack_bottom, function_stack_top); 260 261 if (!dematerialize_error.Success()) 262 { 263 error_stream.Printf("Couldn't apply expression side effects : %s\n", 264 dematerialize_error.AsCString("unknown error")); 265 return false; 266 } 267 268 result = GetResultAfterDematerialization(exe_ctx.GetBestExecutionContextScope()); 269 270 if (result) 271 result->TransferAddress(); 272 273 m_dematerializer_sp.reset(); 274 275 return true; 276 } 277 278 bool 279 LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, ExecutionContext &exe_ctx, 280 lldb::addr_t &struct_address) 281 { 282 lldb::TargetSP target; 283 lldb::ProcessSP process; 284 lldb::StackFrameSP frame; 285 286 if (!LockAndCheckContext(exe_ctx, target, process, frame)) 287 { 288 error_stream.Printf("The context has changed before we could JIT the expression!\n"); 289 return false; 290 } 291 292 if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret) 293 { 294 if (m_materialized_address == LLDB_INVALID_ADDRESS) 295 { 296 Error alloc_error; 297 298 IRMemoryMap::AllocationPolicy policy = 299 m_can_interpret ? IRMemoryMap::eAllocationPolicyHostOnly : IRMemoryMap::eAllocationPolicyMirror; 300 301 const bool zero_memory = false; 302 303 m_materialized_address = m_execution_unit_sp->Malloc(m_materializer_ap->GetStructByteSize(), 304 m_materializer_ap->GetStructAlignment(), 305 lldb::ePermissionsReadable | lldb::ePermissionsWritable, 306 policy, 307 zero_memory, 308 alloc_error); 309 310 if (!alloc_error.Success()) 311 { 312 error_stream.Printf("Couldn't allocate space for materialized struct: %s\n", alloc_error.AsCString()); 313 return false; 314 } 315 } 316 317 struct_address = m_materialized_address; 318 319 if (m_can_interpret && m_stack_frame_bottom == LLDB_INVALID_ADDRESS) 320 { 321 Error alloc_error; 322 323 const size_t stack_frame_size = 512 * 1024; 324 325 const bool zero_memory = false; 326 327 m_stack_frame_bottom = m_execution_unit_sp->Malloc(stack_frame_size, 328 8, 329 lldb::ePermissionsReadable | lldb::ePermissionsWritable, 330 IRMemoryMap::eAllocationPolicyHostOnly, 331 zero_memory, 332 alloc_error); 333 334 m_stack_frame_top = m_stack_frame_bottom + stack_frame_size; 335 336 if (!alloc_error.Success()) 337 { 338 error_stream.Printf("Couldn't allocate space for the stack frame: %s\n", alloc_error.AsCString()); 339 return false; 340 } 341 } 342 343 Error materialize_error; 344 345 m_dematerializer_sp = 346 m_materializer_ap->Materialize(frame, *m_execution_unit_sp, struct_address, materialize_error); 347 348 if (!materialize_error.Success()) 349 { 350 error_stream.Printf("Couldn't materialize: %s\n", materialize_error.AsCString()); 351 return false; 352 } 353 } 354 return true; 355 } 356 357 lldb::ModuleSP 358 LLVMUserExpression::GetJITModule() 359 { 360 if (m_execution_unit_sp) 361 return m_execution_unit_sp->GetJITModule(); 362 return lldb::ModuleSP(); 363 } 364