1 //===-- LLVMUserExpression.cpp ----------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 10 #include "lldb/Expression/LLVMUserExpression.h" 11 #include "lldb/Core/Module.h" 12 #include "lldb/Core/StreamFile.h" 13 #include "lldb/Core/ValueObjectConstResult.h" 14 #include "lldb/Expression/DiagnosticManager.h" 15 #include "lldb/Expression/IRExecutionUnit.h" 16 #include "lldb/Expression/IRInterpreter.h" 17 #include "lldb/Expression/Materializer.h" 18 #include "lldb/Host/HostInfo.h" 19 #include "lldb/Symbol/Block.h" 20 #include "lldb/Symbol/ClangASTContext.h" 21 #include "lldb/Symbol/ClangExternalASTSourceCommon.h" 22 #include "lldb/Symbol/Function.h" 23 #include "lldb/Symbol/ObjectFile.h" 24 #include "lldb/Symbol/SymbolVendor.h" 25 #include "lldb/Symbol/Type.h" 26 #include "lldb/Symbol/VariableList.h" 27 #include "lldb/Target/ExecutionContext.h" 28 #include "lldb/Target/Process.h" 29 #include "lldb/Target/StackFrame.h" 30 #include "lldb/Target/Target.h" 31 #include "lldb/Target/ThreadPlan.h" 32 #include "lldb/Target/ThreadPlanCallUserExpression.h" 33 #include "lldb/Utility/ConstString.h" 34 #include "lldb/Utility/Log.h" 35 #include "lldb/Utility/StreamString.h" 36 37 using namespace lldb_private; 38 39 LLVMUserExpression::LLVMUserExpression(ExecutionContextScope &exe_scope, 40 llvm::StringRef expr, 41 llvm::StringRef prefix, 42 lldb::LanguageType language, 43 ResultType desired_type, 44 const EvaluateExpressionOptions &options) 45 : UserExpression(exe_scope, expr, prefix, language, desired_type, options), 46 m_stack_frame_bottom(LLDB_INVALID_ADDRESS), 47 m_stack_frame_top(LLDB_INVALID_ADDRESS), m_allow_cxx(false), 48 m_allow_objc(false), m_transformed_text(), m_execution_unit_sp(), 49 m_materializer_up(), m_jit_module_wp(), m_enforce_valid_object(true), 50 m_in_cplusplus_method(false), m_in_objectivec_method(false), 51 m_in_static_method(false), m_needs_object_ptr(false), m_target(NULL), 52 m_can_interpret(false), m_materialized_address(LLDB_INVALID_ADDRESS) {} 53 54 LLVMUserExpression::~LLVMUserExpression() { 55 if (m_target) { 56 lldb::ModuleSP jit_module_sp(m_jit_module_wp.lock()); 57 if (jit_module_sp) 58 m_target->GetImages().Remove(jit_module_sp); 59 } 60 } 61 62 lldb::ExpressionResults 63 LLVMUserExpression::DoExecute(DiagnosticManager &diagnostic_manager, 64 ExecutionContext &exe_ctx, 65 const EvaluateExpressionOptions &options, 66 lldb::UserExpressionSP &shared_ptr_to_me, 67 lldb::ExpressionVariableSP &result) { 68 // The expression log is quite verbose, and if you're just tracking the 69 // execution of the expression, it's quite convenient to have these logs come 70 // out with the STEP log as well. 71 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_EXPRESSIONS | 72 LIBLLDB_LOG_STEP)); 73 74 if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret) { 75 lldb::addr_t struct_address = LLDB_INVALID_ADDRESS; 76 77 if (!PrepareToExecuteJITExpression(diagnostic_manager, exe_ctx, 78 struct_address)) { 79 diagnostic_manager.Printf( 80 eDiagnosticSeverityError, 81 "errored out in %s, couldn't PrepareToExecuteJITExpression", 82 __FUNCTION__); 83 return lldb::eExpressionSetupError; 84 } 85 86 lldb::addr_t function_stack_bottom = LLDB_INVALID_ADDRESS; 87 lldb::addr_t function_stack_top = LLDB_INVALID_ADDRESS; 88 89 if (m_can_interpret) { 90 llvm::Module *module = m_execution_unit_sp->GetModule(); 91 llvm::Function *function = m_execution_unit_sp->GetFunction(); 92 93 if (!module || !function) { 94 diagnostic_manager.PutString( 95 eDiagnosticSeverityError, 96 "supposed to interpret, but nothing is there"); 97 return lldb::eExpressionSetupError; 98 } 99 100 Status interpreter_error; 101 102 std::vector<lldb::addr_t> args; 103 104 if (!AddArguments(exe_ctx, args, struct_address, diagnostic_manager)) { 105 diagnostic_manager.Printf(eDiagnosticSeverityError, 106 "errored out in %s, couldn't AddArguments", 107 __FUNCTION__); 108 return lldb::eExpressionSetupError; 109 } 110 111 function_stack_bottom = m_stack_frame_bottom; 112 function_stack_top = m_stack_frame_top; 113 114 IRInterpreter::Interpret(*module, *function, args, *m_execution_unit_sp, 115 interpreter_error, function_stack_bottom, 116 function_stack_top, exe_ctx); 117 118 if (!interpreter_error.Success()) { 119 diagnostic_manager.Printf(eDiagnosticSeverityError, 120 "supposed to interpret, but failed: %s", 121 interpreter_error.AsCString()); 122 return lldb::eExpressionDiscarded; 123 } 124 } else { 125 if (!exe_ctx.HasThreadScope()) { 126 diagnostic_manager.Printf(eDiagnosticSeverityError, 127 "%s called with no thread selected", 128 __FUNCTION__); 129 return lldb::eExpressionSetupError; 130 } 131 132 Address wrapper_address(m_jit_start_addr); 133 134 std::vector<lldb::addr_t> args; 135 136 if (!AddArguments(exe_ctx, args, struct_address, diagnostic_manager)) { 137 diagnostic_manager.Printf(eDiagnosticSeverityError, 138 "errored out in %s, couldn't AddArguments", 139 __FUNCTION__); 140 return lldb::eExpressionSetupError; 141 } 142 143 lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression( 144 exe_ctx.GetThreadRef(), wrapper_address, args, options, 145 shared_ptr_to_me)); 146 147 StreamString ss; 148 if (!call_plan_sp || !call_plan_sp->ValidatePlan(&ss)) { 149 diagnostic_manager.PutString(eDiagnosticSeverityError, ss.GetString()); 150 return lldb::eExpressionSetupError; 151 } 152 153 ThreadPlanCallUserExpression *user_expression_plan = 154 static_cast<ThreadPlanCallUserExpression *>(call_plan_sp.get()); 155 156 lldb::addr_t function_stack_pointer = 157 user_expression_plan->GetFunctionStackPointer(); 158 159 function_stack_bottom = function_stack_pointer - HostInfo::GetPageSize(); 160 function_stack_top = function_stack_pointer; 161 162 if (log) 163 log->Printf( 164 "-- [UserExpression::Execute] Execution of expression begins --"); 165 166 if (exe_ctx.GetProcessPtr()) 167 exe_ctx.GetProcessPtr()->SetRunningUserExpression(true); 168 169 lldb::ExpressionResults execution_result = 170 exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, 171 diagnostic_manager); 172 173 if (exe_ctx.GetProcessPtr()) 174 exe_ctx.GetProcessPtr()->SetRunningUserExpression(false); 175 176 if (log) 177 log->Printf("-- [UserExpression::Execute] Execution of expression " 178 "completed --"); 179 180 if (execution_result == lldb::eExpressionInterrupted || 181 execution_result == lldb::eExpressionHitBreakpoint) { 182 const char *error_desc = NULL; 183 184 if (call_plan_sp) { 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 diagnostic_manager.Printf(eDiagnosticSeverityError, 191 "Execution was interrupted, reason: %s.", 192 error_desc); 193 else 194 diagnostic_manager.PutString(eDiagnosticSeverityError, 195 "Execution was interrupted."); 196 197 if ((execution_result == lldb::eExpressionInterrupted && 198 options.DoesUnwindOnError()) || 199 (execution_result == lldb::eExpressionHitBreakpoint && 200 options.DoesIgnoreBreakpoints())) 201 diagnostic_manager.AppendMessageToDiagnostic( 202 "The process has been returned to the state before expression " 203 "evaluation."); 204 else { 205 if (execution_result == lldb::eExpressionHitBreakpoint) 206 user_expression_plan->TransferExpressionOwnership(); 207 diagnostic_manager.AppendMessageToDiagnostic( 208 "The process has been left at the point where it was " 209 "interrupted, " 210 "use \"thread return -x\" to return to the state before " 211 "expression evaluation."); 212 } 213 214 return execution_result; 215 } else if (execution_result == lldb::eExpressionStoppedForDebug) { 216 diagnostic_manager.PutString( 217 eDiagnosticSeverityRemark, 218 "Execution was halted at the first instruction of the expression " 219 "function because \"debug\" was requested.\n" 220 "Use \"thread return -x\" to return to the state before expression " 221 "evaluation."); 222 return execution_result; 223 } else if (execution_result != lldb::eExpressionCompleted) { 224 diagnostic_manager.Printf( 225 eDiagnosticSeverityError, 226 "Couldn't execute function; result was %s", 227 Process::ExecutionResultAsCString(execution_result)); 228 return execution_result; 229 } 230 } 231 232 if (FinalizeJITExecution(diagnostic_manager, exe_ctx, result, 233 function_stack_bottom, function_stack_top)) { 234 return lldb::eExpressionCompleted; 235 } else { 236 return lldb::eExpressionResultUnavailable; 237 } 238 } else { 239 diagnostic_manager.PutString( 240 eDiagnosticSeverityError, 241 "Expression can't be run, because there is no JIT compiled function"); 242 return lldb::eExpressionSetupError; 243 } 244 } 245 246 bool LLVMUserExpression::FinalizeJITExecution( 247 DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx, 248 lldb::ExpressionVariableSP &result, lldb::addr_t function_stack_bottom, 249 lldb::addr_t function_stack_top) { 250 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); 251 252 if (log) 253 log->Printf("-- [UserExpression::FinalizeJITExecution] Dematerializing " 254 "after execution --"); 255 256 if (!m_dematerializer_sp) { 257 diagnostic_manager.Printf(eDiagnosticSeverityError, 258 "Couldn't apply expression side effects : no " 259 "dematerializer is present"); 260 return false; 261 } 262 263 Status dematerialize_error; 264 265 m_dematerializer_sp->Dematerialize(dematerialize_error, function_stack_bottom, 266 function_stack_top); 267 268 if (!dematerialize_error.Success()) { 269 diagnostic_manager.Printf(eDiagnosticSeverityError, 270 "Couldn't apply expression side effects : %s", 271 dematerialize_error.AsCString("unknown error")); 272 return false; 273 } 274 275 result = 276 GetResultAfterDematerialization(exe_ctx.GetBestExecutionContextScope()); 277 278 if (result) 279 result->TransferAddress(); 280 281 m_dematerializer_sp.reset(); 282 283 return true; 284 } 285 286 bool LLVMUserExpression::PrepareToExecuteJITExpression( 287 DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx, 288 lldb::addr_t &struct_address) { 289 lldb::TargetSP target; 290 lldb::ProcessSP process; 291 lldb::StackFrameSP frame; 292 293 if (!LockAndCheckContext(exe_ctx, target, process, frame)) { 294 diagnostic_manager.PutString( 295 eDiagnosticSeverityError, 296 "The context has changed before we could JIT the expression!"); 297 return false; 298 } 299 300 if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret) { 301 if (m_materialized_address == LLDB_INVALID_ADDRESS) { 302 Status alloc_error; 303 304 IRMemoryMap::AllocationPolicy policy = 305 m_can_interpret ? IRMemoryMap::eAllocationPolicyHostOnly 306 : IRMemoryMap::eAllocationPolicyMirror; 307 308 const bool zero_memory = false; 309 310 m_materialized_address = m_execution_unit_sp->Malloc( 311 m_materializer_up->GetStructByteSize(), 312 m_materializer_up->GetStructAlignment(), 313 lldb::ePermissionsReadable | lldb::ePermissionsWritable, policy, 314 zero_memory, alloc_error); 315 316 if (!alloc_error.Success()) { 317 diagnostic_manager.Printf( 318 eDiagnosticSeverityError, 319 "Couldn't allocate space for materialized struct: %s", 320 alloc_error.AsCString()); 321 return false; 322 } 323 } 324 325 struct_address = m_materialized_address; 326 327 if (m_can_interpret && m_stack_frame_bottom == LLDB_INVALID_ADDRESS) { 328 Status alloc_error; 329 330 const size_t stack_frame_size = 512 * 1024; 331 332 const bool zero_memory = false; 333 334 m_stack_frame_bottom = m_execution_unit_sp->Malloc( 335 stack_frame_size, 8, 336 lldb::ePermissionsReadable | lldb::ePermissionsWritable, 337 IRMemoryMap::eAllocationPolicyHostOnly, zero_memory, alloc_error); 338 339 m_stack_frame_top = m_stack_frame_bottom + stack_frame_size; 340 341 if (!alloc_error.Success()) { 342 diagnostic_manager.Printf( 343 eDiagnosticSeverityError, 344 "Couldn't allocate space for the stack frame: %s", 345 alloc_error.AsCString()); 346 return false; 347 } 348 } 349 350 Status materialize_error; 351 352 m_dematerializer_sp = m_materializer_up->Materialize( 353 frame, *m_execution_unit_sp, struct_address, materialize_error); 354 355 if (!materialize_error.Success()) { 356 diagnostic_manager.Printf(eDiagnosticSeverityError, 357 "Couldn't materialize: %s", 358 materialize_error.AsCString()); 359 return false; 360 } 361 } 362 return true; 363 } 364 365 lldb::ModuleSP LLVMUserExpression::GetJITModule() { 366 if (m_execution_unit_sp) 367 return m_execution_unit_sp->GetJITModule(); 368 return lldb::ModuleSP(); 369 } 370