1 //===-- ThreadPlanStepOverRange.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 #include "lldb/Target/ThreadPlanStepOverRange.h" 11 12 // C Includes 13 // C++ Includes 14 // Other libraries and framework includes 15 // Project includes 16 17 #include "lldb/lldb-private-log.h" 18 #include "lldb/Core/Log.h" 19 #include "lldb/Core/Stream.h" 20 #include "lldb/Symbol/Block.h" 21 #include "lldb/Symbol/CompileUnit.h" 22 #include "lldb/Symbol/Function.h" 23 #include "lldb/Symbol/LineTable.h" 24 #include "lldb/Target/Process.h" 25 #include "lldb/Target/RegisterContext.h" 26 #include "lldb/Target/Target.h" 27 #include "lldb/Target/Thread.h" 28 #include "lldb/Target/ThreadPlanStepOut.h" 29 #include "lldb/Target/ThreadPlanStepThrough.h" 30 31 using namespace lldb_private; 32 using namespace lldb; 33 34 uint32_t ThreadPlanStepOverRange::s_default_flag_values = 0; 35 36 //---------------------------------------------------------------------- 37 // ThreadPlanStepOverRange: Step through a stack range, either stepping over or into 38 // based on the value of \a type. 39 //---------------------------------------------------------------------- 40 41 ThreadPlanStepOverRange::ThreadPlanStepOverRange 42 ( 43 Thread &thread, 44 const AddressRange &range, 45 const SymbolContext &addr_context, 46 lldb::RunMode stop_others, 47 LazyBool step_out_avoids_code_without_debug_info 48 ) : 49 ThreadPlanStepRange (ThreadPlan::eKindStepOverRange, "Step range stepping over", thread, range, addr_context, stop_others), 50 ThreadPlanShouldStopHere (this), 51 m_first_resume(true) 52 { 53 SetFlagsToDefault(); 54 SetupAvoidNoDebug(step_out_avoids_code_without_debug_info); 55 } 56 57 ThreadPlanStepOverRange::~ThreadPlanStepOverRange () 58 { 59 } 60 61 void 62 ThreadPlanStepOverRange::GetDescription (Stream *s, lldb::DescriptionLevel level) 63 { 64 if (level == lldb::eDescriptionLevelBrief) 65 s->Printf("step over"); 66 else 67 { 68 s->Printf ("stepping through range (stepping over functions): "); 69 DumpRanges(s); 70 } 71 } 72 73 void 74 ThreadPlanStepOverRange::SetupAvoidNoDebug(LazyBool step_out_avoids_code_without_debug_info) 75 { 76 bool avoid_nodebug = true; 77 switch (step_out_avoids_code_without_debug_info) 78 { 79 case eLazyBoolYes: 80 avoid_nodebug = true; 81 break; 82 case eLazyBoolNo: 83 avoid_nodebug = false; 84 break; 85 case eLazyBoolCalculate: 86 avoid_nodebug = m_thread.GetStepOutAvoidsNoDebug(); 87 break; 88 } 89 if (avoid_nodebug) 90 GetFlags().Set (ThreadPlanShouldStopHere::eStepOutAvoidNoDebug); 91 else 92 GetFlags().Clear (ThreadPlanShouldStopHere::eStepOutAvoidNoDebug); 93 } 94 95 bool 96 ThreadPlanStepOverRange::IsEquivalentContext(const SymbolContext &context) 97 { 98 99 // Match as much as is specified in the m_addr_context: 100 // This is a fairly loose sanity check. Note, sometimes the target doesn't get filled 101 // in so I left out the target check. And sometimes the module comes in as the .o file from the 102 // inlined range, so I left that out too... 103 if (m_addr_context.comp_unit) 104 { 105 if (m_addr_context.comp_unit == context.comp_unit) 106 { 107 if (m_addr_context.function && m_addr_context.function == context.function) 108 { 109 if (m_addr_context.block && m_addr_context.block == context.block) 110 return true; 111 } 112 } 113 } 114 else if (m_addr_context.symbol && m_addr_context.symbol == context.symbol) 115 { 116 return true; 117 } 118 return false; 119 } 120 121 bool 122 ThreadPlanStepOverRange::ShouldStop (Event *event_ptr) 123 { 124 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP)); 125 126 if (log) 127 { 128 StreamString s; 129 s.Address (m_thread.GetRegisterContext()->GetPC(), 130 m_thread.CalculateTarget()->GetArchitecture().GetAddressByteSize()); 131 log->Printf("ThreadPlanStepOverRange reached %s.", s.GetData()); 132 } 133 134 // If we're out of the range but in the same frame or in our caller's frame 135 // then we should stop. 136 // When stepping out we only stop others if we are forcing running one thread. 137 bool stop_others; 138 if (m_stop_others == lldb::eOnlyThisThread) 139 stop_others = true; 140 else 141 stop_others = false; 142 143 ThreadPlanSP new_plan_sp; 144 145 FrameComparison frame_order = CompareCurrentFrameToStartFrame(); 146 147 if (frame_order == eFrameCompareOlder) 148 { 149 // If we're in an older frame then we should stop. 150 // 151 // A caveat to this is if we think the frame is older but we're actually in a trampoline. 152 // I'm going to make the assumption that you wouldn't RETURN to a trampoline. So if we are 153 // in a trampoline we think the frame is older because the trampoline confused the backtracer. 154 // As below, we step through first, and then try to figure out how to get back out again. 155 156 new_plan_sp = m_thread.QueueThreadPlanForStepThrough (m_stack_id, false, stop_others); 157 158 if (new_plan_sp && log) 159 log->Printf("Thought I stepped out, but in fact arrived at a trampoline."); 160 } 161 else if (frame_order == eFrameCompareYounger) 162 { 163 // Make sure we really are in a new frame. Do that by unwinding and seeing if the 164 // start function really is our start function... 165 for(uint32_t i = 1;; ++i) 166 { 167 StackFrameSP older_frame_sp = m_thread.GetStackFrameAtIndex(i); 168 if (!older_frame_sp) { 169 // We can't unwind the next frame we should just get out of here & stop... 170 break; 171 } 172 173 const SymbolContext &older_context = older_frame_sp->GetSymbolContext(eSymbolContextEverything); 174 if (IsEquivalentContext(older_context)) 175 { 176 new_plan_sp = m_thread.QueueThreadPlanForStepOutNoShouldStop (false, 177 NULL, 178 true, 179 stop_others, 180 eVoteNo, 181 eVoteNoOpinion, 182 0); 183 break; 184 } 185 else 186 { 187 new_plan_sp = m_thread.QueueThreadPlanForStepThrough (m_stack_id, false, stop_others); 188 } 189 } 190 } 191 else 192 { 193 // If we're still in the range, keep going. 194 if (InRange()) 195 { 196 SetNextBranchBreakpoint(); 197 return false; 198 } 199 200 201 if (!InSymbol()) 202 { 203 // This one is a little tricky. Sometimes we may be in a stub or something similar, 204 // in which case we need to get out of there. But if we are in a stub then it's 205 // likely going to be hard to get out from here. It is probably easiest to step into the 206 // stub, and then it will be straight-forward to step out. 207 new_plan_sp = m_thread.QueueThreadPlanForStepThrough (m_stack_id, false, stop_others); 208 } 209 else 210 { 211 // The current clang (at least through 424) doesn't always get the address range for the 212 // DW_TAG_inlined_subroutines right, so that when you leave the inlined range the line table says 213 // you are still in the source file of the inlining function. This is bad, because now you are missing 214 // the stack frame for the function containing the inlining, and if you sensibly do "finish" to get 215 // out of this function you will instead exit the containing function. 216 // To work around this, we check whether we are still in the source file we started in, and if not assume 217 // it is an error, and push a plan to get us out of this line and back to the containing file. 218 219 if (m_addr_context.line_entry.IsValid()) 220 { 221 SymbolContext sc; 222 StackFrameSP frame_sp = m_thread.GetStackFrameAtIndex(0); 223 sc = frame_sp->GetSymbolContext (eSymbolContextEverything); 224 if (sc.line_entry.IsValid()) 225 { 226 if (sc.line_entry.file != m_addr_context.line_entry.file 227 && sc.comp_unit == m_addr_context.comp_unit 228 && sc.function == m_addr_context.function) 229 { 230 // Okay, find the next occurance of this file in the line table: 231 LineTable *line_table = m_addr_context.comp_unit->GetLineTable(); 232 if (line_table) 233 { 234 Address cur_address = frame_sp->GetFrameCodeAddress(); 235 uint32_t entry_idx; 236 LineEntry line_entry; 237 if (line_table->FindLineEntryByAddress (cur_address, line_entry, &entry_idx)) 238 { 239 LineEntry next_line_entry; 240 bool step_past_remaining_inline = false; 241 if (entry_idx > 0) 242 { 243 // We require the the previous line entry and the current line entry come 244 // from the same file. 245 // The other requirement is that the previous line table entry be part of an 246 // inlined block, we don't want to step past cases where people have inlined 247 // some code fragment by using #include <source-fragment.c> directly. 248 LineEntry prev_line_entry; 249 if (line_table->GetLineEntryAtIndex(entry_idx - 1, prev_line_entry) 250 && prev_line_entry.file == line_entry.file) 251 { 252 SymbolContext prev_sc; 253 Address prev_address = prev_line_entry.range.GetBaseAddress(); 254 prev_address.CalculateSymbolContext(&prev_sc); 255 if (prev_sc.block) 256 { 257 Block *inlined_block = prev_sc.block->GetContainingInlinedBlock(); 258 if (inlined_block) 259 { 260 AddressRange inline_range; 261 inlined_block->GetRangeContainingAddress(prev_address, inline_range); 262 if (!inline_range.ContainsFileAddress(cur_address)) 263 { 264 265 step_past_remaining_inline = true; 266 } 267 268 } 269 } 270 } 271 } 272 273 if (step_past_remaining_inline) 274 { 275 uint32_t look_ahead_step = 1; 276 while (line_table->GetLineEntryAtIndex(entry_idx + look_ahead_step, next_line_entry)) 277 { 278 // Make sure we haven't wandered out of the function we started from... 279 Address next_line_address = next_line_entry.range.GetBaseAddress(); 280 Function *next_line_function = next_line_address.CalculateSymbolContextFunction(); 281 if (next_line_function != m_addr_context.function) 282 break; 283 284 if (next_line_entry.file == m_addr_context.line_entry.file) 285 { 286 const bool abort_other_plans = false; 287 const bool stop_other_threads = false; 288 new_plan_sp = m_thread.QueueThreadPlanForRunToAddress(abort_other_plans, 289 next_line_address, 290 stop_other_threads); 291 break; 292 } 293 look_ahead_step++; 294 } 295 } 296 } 297 } 298 } 299 } 300 } 301 } 302 } 303 304 // If we get to this point, we're not going to use a previously set "next branch" breakpoint, so delete it: 305 ClearNextBranchBreakpoint(); 306 307 308 // If we haven't figured out something to do yet, then ask the ShouldStopHere callback: 309 if (!new_plan_sp) 310 { 311 new_plan_sp = CheckShouldStopHereAndQueueStepOut (frame_order); 312 } 313 314 if (!new_plan_sp) 315 m_no_more_plans = true; 316 else 317 m_no_more_plans = false; 318 319 if (!new_plan_sp) 320 { 321 // For efficiencies sake, we know we're done here so we don't have to do this 322 // calculation again in MischiefManaged. 323 SetPlanComplete(); 324 return true; 325 } 326 else 327 return false; 328 } 329 330 bool 331 ThreadPlanStepOverRange::DoPlanExplainsStop (Event *event_ptr) 332 { 333 // For crashes, breakpoint hits, signals, etc, let the base plan (or some plan above us) 334 // handle the stop. That way the user can see the stop, step around, and then when they 335 // are done, continue and have their step complete. The exception is if we've hit our 336 // "run to next branch" breakpoint. 337 // Note, unlike the step in range plan, we don't mark ourselves complete if we hit an 338 // unexplained breakpoint/crash. 339 340 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP)); 341 StopInfoSP stop_info_sp = GetPrivateStopInfo (); 342 bool return_value; 343 344 if (stop_info_sp) 345 { 346 StopReason reason = stop_info_sp->GetStopReason(); 347 348 switch (reason) 349 { 350 case eStopReasonTrace: 351 return_value = true; 352 break; 353 case eStopReasonBreakpoint: 354 if (NextRangeBreakpointExplainsStop(stop_info_sp)) 355 return_value = true; 356 else 357 return_value = false; 358 break; 359 case eStopReasonWatchpoint: 360 case eStopReasonSignal: 361 case eStopReasonException: 362 case eStopReasonExec: 363 case eStopReasonThreadExiting: 364 default: 365 if (log) 366 log->PutCString ("ThreadPlanStepInRange got asked if it explains the stop for some reason other than step."); 367 return_value = false; 368 break; 369 } 370 } 371 else 372 return_value = true; 373 374 return return_value; 375 } 376 377 bool 378 ThreadPlanStepOverRange::DoWillResume (lldb::StateType resume_state, bool current_plan) 379 { 380 if (resume_state != eStateSuspended && m_first_resume) 381 { 382 m_first_resume = false; 383 if (resume_state == eStateStepping && current_plan) 384 { 385 // See if we are about to step over an inlined call in the middle of the inlined stack, if so figure 386 // out its extents and reset our range to step over that. 387 bool in_inlined_stack = m_thread.DecrementCurrentInlinedDepth(); 388 if (in_inlined_stack) 389 { 390 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP)); 391 if (log) 392 log->Printf ("ThreadPlanStepInRange::DoWillResume: adjusting range to the frame at inlined depth %d.", 393 m_thread.GetCurrentInlinedDepth()); 394 StackFrameSP stack_sp = m_thread.GetStackFrameAtIndex(0); 395 if (stack_sp) 396 { 397 Block *frame_block = stack_sp->GetFrameBlock(); 398 lldb::addr_t curr_pc = m_thread.GetRegisterContext()->GetPC(); 399 AddressRange my_range; 400 if (frame_block->GetRangeContainingLoadAddress(curr_pc, m_thread.GetProcess()->GetTarget(), my_range)) 401 { 402 m_address_ranges.clear(); 403 m_address_ranges.push_back(my_range); 404 if (log) 405 { 406 StreamString s; 407 const InlineFunctionInfo *inline_info = frame_block->GetInlinedFunctionInfo(); 408 const char *name; 409 if (inline_info) 410 name = inline_info->GetName().AsCString(); 411 else 412 name = "<unknown-notinlined>"; 413 414 s.Printf ("Stepping over inlined function \"%s\" in inlined stack: ", name); 415 DumpRanges(&s); 416 log->PutCString(s.GetData()); 417 } 418 } 419 420 } 421 } 422 } 423 } 424 425 return true; 426 } 427 428