1 //===-- StopInfoMachException.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 "StopInfoMachException.h" 11 12 // C Includes 13 #include <kern/exc_resource.h> 14 15 // C++ Includes 16 // Other libraries and framework includes 17 // Project includes 18 #include "lldb/Breakpoint/Watchpoint.h" 19 #include "lldb/Symbol/Symbol.h" 20 #include "lldb/Target/DynamicLoader.h" 21 #include "lldb/Target/ExecutionContext.h" 22 #include "lldb/Target/Process.h" 23 #include "lldb/Target/RegisterContext.h" 24 #include "lldb/Target/Target.h" 25 #include "lldb/Target/Thread.h" 26 #include "lldb/Target/ThreadPlan.h" 27 #include "lldb/Target/UnixSignals.h" 28 #include "lldb/Utility/StreamString.h" 29 30 using namespace lldb; 31 using namespace lldb_private; 32 33 const char *StopInfoMachException::GetDescription() { 34 if (m_description.empty() && m_value != 0) { 35 ExecutionContext exe_ctx(m_thread_wp.lock()); 36 Target *target = exe_ctx.GetTargetPtr(); 37 const llvm::Triple::ArchType cpu = 38 target ? target->GetArchitecture().GetMachine() 39 : llvm::Triple::UnknownArch; 40 41 const char *exc_desc = NULL; 42 const char *code_label = "code"; 43 const char *code_desc = NULL; 44 const char *subcode_label = "subcode"; 45 const char *subcode_desc = NULL; 46 47 char code_desc_buf[32]; 48 char subcode_desc_buf[32]; 49 50 switch (m_value) { 51 case 1: // EXC_BAD_ACCESS 52 exc_desc = "EXC_BAD_ACCESS"; 53 subcode_label = "address"; 54 switch (cpu) { 55 case llvm::Triple::x86: 56 case llvm::Triple::x86_64: 57 switch (m_exc_code) { 58 case 0xd: 59 code_desc = "EXC_I386_GPFLT"; 60 m_exc_data_count = 1; 61 break; 62 } 63 break; 64 case llvm::Triple::arm: 65 case llvm::Triple::thumb: 66 switch (m_exc_code) { 67 case 0x101: 68 code_desc = "EXC_ARM_DA_ALIGN"; 69 break; 70 case 0x102: 71 code_desc = "EXC_ARM_DA_DEBUG"; 72 break; 73 } 74 break; 75 76 case llvm::Triple::ppc: 77 case llvm::Triple::ppc64: 78 switch (m_exc_code) { 79 case 0x101: 80 code_desc = "EXC_PPC_VM_PROT_READ"; 81 break; 82 case 0x102: 83 code_desc = "EXC_PPC_BADSPACE"; 84 break; 85 case 0x103: 86 code_desc = "EXC_PPC_UNALIGNED"; 87 break; 88 } 89 break; 90 91 default: 92 break; 93 } 94 break; 95 96 case 2: // EXC_BAD_INSTRUCTION 97 exc_desc = "EXC_BAD_INSTRUCTION"; 98 switch (cpu) { 99 case llvm::Triple::x86: 100 case llvm::Triple::x86_64: 101 if (m_exc_code == 1) 102 code_desc = "EXC_I386_INVOP"; 103 break; 104 105 case llvm::Triple::ppc: 106 case llvm::Triple::ppc64: 107 switch (m_exc_code) { 108 case 1: 109 code_desc = "EXC_PPC_INVALID_SYSCALL"; 110 break; 111 case 2: 112 code_desc = "EXC_PPC_UNIPL_INST"; 113 break; 114 case 3: 115 code_desc = "EXC_PPC_PRIVINST"; 116 break; 117 case 4: 118 code_desc = "EXC_PPC_PRIVREG"; 119 break; 120 case 5: 121 code_desc = "EXC_PPC_TRACE"; 122 break; 123 case 6: 124 code_desc = "EXC_PPC_PERFMON"; 125 break; 126 } 127 break; 128 129 case llvm::Triple::arm: 130 case llvm::Triple::thumb: 131 if (m_exc_code == 1) 132 code_desc = "EXC_ARM_UNDEFINED"; 133 break; 134 135 default: 136 break; 137 } 138 break; 139 140 case 3: // EXC_ARITHMETIC 141 exc_desc = "EXC_ARITHMETIC"; 142 switch (cpu) { 143 case llvm::Triple::x86: 144 case llvm::Triple::x86_64: 145 switch (m_exc_code) { 146 case 1: 147 code_desc = "EXC_I386_DIV"; 148 break; 149 case 2: 150 code_desc = "EXC_I386_INTO"; 151 break; 152 case 3: 153 code_desc = "EXC_I386_NOEXT"; 154 break; 155 case 4: 156 code_desc = "EXC_I386_EXTOVR"; 157 break; 158 case 5: 159 code_desc = "EXC_I386_EXTERR"; 160 break; 161 case 6: 162 code_desc = "EXC_I386_EMERR"; 163 break; 164 case 7: 165 code_desc = "EXC_I386_BOUND"; 166 break; 167 case 8: 168 code_desc = "EXC_I386_SSEEXTERR"; 169 break; 170 } 171 break; 172 173 case llvm::Triple::ppc: 174 case llvm::Triple::ppc64: 175 switch (m_exc_code) { 176 case 1: 177 code_desc = "EXC_PPC_OVERFLOW"; 178 break; 179 case 2: 180 code_desc = "EXC_PPC_ZERO_DIVIDE"; 181 break; 182 case 3: 183 code_desc = "EXC_PPC_FLT_INEXACT"; 184 break; 185 case 4: 186 code_desc = "EXC_PPC_FLT_ZERO_DIVIDE"; 187 break; 188 case 5: 189 code_desc = "EXC_PPC_FLT_UNDERFLOW"; 190 break; 191 case 6: 192 code_desc = "EXC_PPC_FLT_OVERFLOW"; 193 break; 194 case 7: 195 code_desc = "EXC_PPC_FLT_NOT_A_NUMBER"; 196 break; 197 } 198 break; 199 200 default: 201 break; 202 } 203 break; 204 205 case 4: // EXC_EMULATION 206 exc_desc = "EXC_EMULATION"; 207 break; 208 209 case 5: // EXC_SOFTWARE 210 exc_desc = "EXC_SOFTWARE"; 211 if (m_exc_code == 0x10003) { 212 subcode_desc = "EXC_SOFT_SIGNAL"; 213 subcode_label = "signo"; 214 } 215 break; 216 217 case 6: // EXC_BREAKPOINT 218 { 219 exc_desc = "EXC_BREAKPOINT"; 220 switch (cpu) { 221 case llvm::Triple::x86: 222 case llvm::Triple::x86_64: 223 switch (m_exc_code) { 224 case 1: 225 code_desc = "EXC_I386_SGL"; 226 break; 227 case 2: 228 code_desc = "EXC_I386_BPT"; 229 break; 230 } 231 break; 232 233 case llvm::Triple::ppc: 234 case llvm::Triple::ppc64: 235 switch (m_exc_code) { 236 case 1: 237 code_desc = "EXC_PPC_BREAKPOINT"; 238 break; 239 } 240 break; 241 242 case llvm::Triple::arm: 243 case llvm::Triple::thumb: 244 switch (m_exc_code) { 245 case 0x101: 246 code_desc = "EXC_ARM_DA_ALIGN"; 247 break; 248 case 0x102: 249 code_desc = "EXC_ARM_DA_DEBUG"; 250 break; 251 case 1: 252 code_desc = "EXC_ARM_BREAKPOINT"; 253 break; 254 // FIXME temporary workaround, exc_code 0 does not really mean 255 // EXC_ARM_BREAKPOINT 256 case 0: 257 code_desc = "EXC_ARM_BREAKPOINT"; 258 break; 259 } 260 break; 261 262 default: 263 break; 264 } 265 } break; 266 267 case 7: 268 exc_desc = "EXC_SYSCALL"; 269 break; 270 271 case 8: 272 exc_desc = "EXC_MACH_SYSCALL"; 273 break; 274 275 case 9: 276 exc_desc = "EXC_RPC_ALERT"; 277 break; 278 279 case 10: 280 exc_desc = "EXC_CRASH"; 281 break; 282 case 11: 283 exc_desc = "EXC_RESOURCE"; 284 { 285 int resource_type = EXC_RESOURCE_DECODE_RESOURCE_TYPE(m_exc_code); 286 287 code_label = "limit"; 288 code_desc = code_desc_buf; 289 subcode_label = "observed"; 290 subcode_desc = subcode_desc_buf; 291 292 switch (resource_type) { 293 case RESOURCE_TYPE_CPU: 294 exc_desc = "EXC_RESOURCE RESOURCE_TYPE_CPU"; 295 snprintf(code_desc_buf, sizeof(code_desc_buf), "%d%%", 296 (int)EXC_RESOURCE_CPUMONITOR_DECODE_PERCENTAGE(m_exc_code)); 297 snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d%%", 298 (int)EXC_RESOURCE_CPUMONITOR_DECODE_PERCENTAGE_OBSERVED(m_exc_subcode)); 299 break; 300 case RESOURCE_TYPE_WAKEUPS: 301 exc_desc = "EXC_RESOURCE RESOURCE_TYPE_WAKEUPS"; 302 snprintf(code_desc_buf, sizeof(code_desc_buf), "%d w/s", 303 (int)EXC_RESOURCE_CPUMONITOR_DECODE_WAKEUPS_PERMITTED(m_exc_code)); 304 snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d w/s", 305 (int)EXC_RESOURCE_CPUMONITOR_DECODE_WAKEUPS_OBSERVED(m_exc_subcode)); 306 break; 307 case RESOURCE_TYPE_MEMORY: 308 exc_desc = "EXC_RESOURCE RESOURCE_TYPE_MEMORY"; 309 snprintf(code_desc_buf, sizeof(code_desc_buf), "%d MB", 310 (int)EXC_RESOURCE_HWM_DECODE_LIMIT(m_exc_code)); 311 subcode_desc = nullptr; 312 subcode_label = "unused"; 313 break; 314 case RESOURCE_TYPE_IO: 315 exc_desc = "EXC_RESOURCE RESOURCE_TYPE_IO"; 316 snprintf(code_desc_buf, sizeof(code_desc_buf), "%d MB", 317 (int)EXC_RESOURCE_IO_DECODE_LIMIT(m_exc_code)); 318 snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d MB", 319 (int)EXC_RESOURCE_IO_OBSERVED(m_exc_subcode));; 320 break; 321 } 322 } 323 break; 324 case 12: 325 exc_desc = "EXC_GUARD"; 326 break; 327 } 328 329 StreamString strm; 330 331 if (exc_desc) 332 strm.PutCString(exc_desc); 333 else 334 strm.Printf("EXC_??? (%" PRIu64 ")", m_value); 335 336 if (m_exc_data_count >= 1) { 337 if (code_desc) 338 strm.Printf(" (%s=%s", code_label, code_desc); 339 else 340 strm.Printf(" (%s=%" PRIu64, code_label, m_exc_code); 341 } 342 343 if (m_exc_data_count >= 2) { 344 if (subcode_desc) 345 strm.Printf(", %s=%s", subcode_label, subcode_desc); 346 else 347 strm.Printf(", %s=0x%" PRIx64, subcode_label, m_exc_subcode); 348 } 349 350 if (m_exc_data_count > 0) 351 strm.PutChar(')'); 352 353 m_description = strm.GetString(); 354 } 355 return m_description.c_str(); 356 } 357 358 StopInfoSP StopInfoMachException::CreateStopReasonWithMachException( 359 Thread &thread, uint32_t exc_type, uint32_t exc_data_count, 360 uint64_t exc_code, uint64_t exc_sub_code, uint64_t exc_sub_sub_code, 361 bool pc_already_adjusted, bool adjust_pc_if_needed) { 362 if (exc_type != 0) { 363 uint32_t pc_decrement = 0; 364 ExecutionContext exe_ctx(thread.shared_from_this()); 365 Target *target = exe_ctx.GetTargetPtr(); 366 const llvm::Triple::ArchType cpu = 367 target ? target->GetArchitecture().GetMachine() 368 : llvm::Triple::UnknownArch; 369 370 switch (exc_type) { 371 case 1: // EXC_BAD_ACCESS 372 break; 373 374 case 2: // EXC_BAD_INSTRUCTION 375 switch (cpu) { 376 case llvm::Triple::ppc: 377 case llvm::Triple::ppc64: 378 switch (exc_code) { 379 case 1: // EXC_PPC_INVALID_SYSCALL 380 case 2: // EXC_PPC_UNIPL_INST 381 case 3: // EXC_PPC_PRIVINST 382 case 4: // EXC_PPC_PRIVREG 383 break; 384 case 5: // EXC_PPC_TRACE 385 return StopInfo::CreateStopReasonToTrace(thread); 386 case 6: // EXC_PPC_PERFMON 387 break; 388 } 389 break; 390 391 default: 392 break; 393 } 394 break; 395 396 case 3: // EXC_ARITHMETIC 397 case 4: // EXC_EMULATION 398 break; 399 400 case 5: // EXC_SOFTWARE 401 if (exc_code == 0x10003) // EXC_SOFT_SIGNAL 402 { 403 if (exc_sub_code == 5) { 404 // On MacOSX, a SIGTRAP can signify that a process has called exec, 405 // so we should check with our dynamic loader to verify. 406 ProcessSP process_sp(thread.GetProcess()); 407 if (process_sp) { 408 DynamicLoader *dynamic_loader = process_sp->GetDynamicLoader(); 409 if (dynamic_loader && dynamic_loader->ProcessDidExec()) { 410 // The program was re-exec'ed 411 return StopInfo::CreateStopReasonWithExec(thread); 412 } 413 // if (!process_did_exec) 414 // { 415 // // We have a SIGTRAP, make sure we 416 // didn't exec by checking 417 // // for the PC being at 418 // "_dyld_start"... 419 // lldb::StackFrameSP frame_sp 420 // (thread.GetStackFrameAtIndex(0)); 421 // if (frame_sp) 422 // { 423 // const Symbol *symbol = 424 // frame_sp->GetSymbolContext(eSymbolContextSymbol).symbol; 425 // if (symbol) 426 // { 427 // if (symbol->GetName() == 428 // ConstString("_dyld_start")) 429 // process_did_exec = true; 430 // } 431 // } 432 // } 433 } 434 } 435 return StopInfo::CreateStopReasonWithSignal(thread, exc_sub_code); 436 } 437 break; 438 439 case 6: // EXC_BREAKPOINT 440 { 441 bool is_actual_breakpoint = false; 442 bool is_trace_if_actual_breakpoint_missing = false; 443 switch (cpu) { 444 case llvm::Triple::x86: 445 case llvm::Triple::x86_64: 446 if (exc_code == 1) // EXC_I386_SGL 447 { 448 if (!exc_sub_code) { 449 // This looks like a plain trap. 450 // Have to check if there is a breakpoint here as well. When you 451 // single-step onto a trap, the single step stops you not to trap. 452 // Since we also do that check below, let's just use that logic. 453 is_actual_breakpoint = true; 454 is_trace_if_actual_breakpoint_missing = true; 455 } else { 456 457 // It's a watchpoint, then. 458 // The exc_sub_code indicates the data break address. 459 lldb::WatchpointSP wp_sp; 460 if (target) 461 wp_sp = target->GetWatchpointList().FindByAddress( 462 (lldb::addr_t)exc_sub_code); 463 if (wp_sp && wp_sp->IsEnabled()) { 464 // Debugserver may piggyback the hardware index of the fired 465 // watchpoint in the exception data. Set the hardware index if 466 // that's the case. 467 if (exc_data_count >= 3) 468 wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code); 469 return StopInfo::CreateStopReasonWithWatchpointID(thread, 470 wp_sp->GetID()); 471 } 472 } 473 } else if (exc_code == 2 || // EXC_I386_BPT 474 exc_code == 3) // EXC_I386_BPTFLT 475 { 476 // KDP returns EXC_I386_BPTFLT for trace breakpoints 477 if (exc_code == 3) 478 is_trace_if_actual_breakpoint_missing = true; 479 480 is_actual_breakpoint = true; 481 if (!pc_already_adjusted) 482 pc_decrement = 1; 483 } 484 break; 485 486 case llvm::Triple::ppc: 487 case llvm::Triple::ppc64: 488 is_actual_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT 489 break; 490 491 case llvm::Triple::arm: 492 case llvm::Triple::thumb: 493 if (exc_code == 0x102) // EXC_ARM_DA_DEBUG 494 { 495 // It's a watchpoint, then, if the exc_sub_code indicates a 496 // known/enabled data break address from our watchpoint list. 497 lldb::WatchpointSP wp_sp; 498 if (target) 499 wp_sp = target->GetWatchpointList().FindByAddress( 500 (lldb::addr_t)exc_sub_code); 501 if (wp_sp && wp_sp->IsEnabled()) { 502 // Debugserver may piggyback the hardware index of the fired 503 // watchpoint in the exception data. Set the hardware index if 504 // that's the case. 505 if (exc_data_count >= 3) 506 wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code); 507 return StopInfo::CreateStopReasonWithWatchpointID(thread, 508 wp_sp->GetID()); 509 } else { 510 is_actual_breakpoint = true; 511 is_trace_if_actual_breakpoint_missing = true; 512 } 513 } else if (exc_code == 1) // EXC_ARM_BREAKPOINT 514 { 515 is_actual_breakpoint = true; 516 is_trace_if_actual_breakpoint_missing = true; 517 } else if (exc_code == 0) // FIXME not EXC_ARM_BREAKPOINT but a kernel 518 // is currently returning this so accept it 519 // as indicating a breakpoint until the 520 // kernel is fixed 521 { 522 is_actual_breakpoint = true; 523 is_trace_if_actual_breakpoint_missing = true; 524 } 525 break; 526 527 case llvm::Triple::aarch64: { 528 if (exc_code == 1 && exc_sub_code == 0) // EXC_ARM_BREAKPOINT 529 { 530 // This is hit when we single instruction step aka MDSCR_EL1 SS bit 0 531 // is set 532 is_actual_breakpoint = false; 533 is_trace_if_actual_breakpoint_missing = true; 534 } 535 if (exc_code == 0x102) // EXC_ARM_DA_DEBUG 536 { 537 // It's a watchpoint, then, if the exc_sub_code indicates a 538 // known/enabled data break address from our watchpoint list. 539 lldb::WatchpointSP wp_sp; 540 if (target) 541 wp_sp = target->GetWatchpointList().FindByAddress( 542 (lldb::addr_t)exc_sub_code); 543 if (wp_sp && wp_sp->IsEnabled()) { 544 // Debugserver may piggyback the hardware index of the fired 545 // watchpoint in the exception data. Set the hardware index if 546 // that's the case. 547 if (exc_data_count >= 3) 548 wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code); 549 return StopInfo::CreateStopReasonWithWatchpointID(thread, 550 wp_sp->GetID()); 551 } 552 // EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as 553 // EXC_BAD_ACCESS 554 if (thread.GetTemporaryResumeState() == eStateStepping) 555 return StopInfo::CreateStopReasonToTrace(thread); 556 } 557 // It looks like exc_sub_code has the 4 bytes of the instruction that 558 // triggered the exception, i.e. our breakpoint opcode 559 is_actual_breakpoint = exc_code == 1; 560 break; 561 } 562 563 default: 564 break; 565 } 566 567 if (is_actual_breakpoint) { 568 RegisterContextSP reg_ctx_sp(thread.GetRegisterContext()); 569 addr_t pc = reg_ctx_sp->GetPC() - pc_decrement; 570 571 ProcessSP process_sp(thread.CalculateProcess()); 572 573 lldb::BreakpointSiteSP bp_site_sp; 574 if (process_sp) 575 bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc); 576 if (bp_site_sp && bp_site_sp->IsEnabled()) { 577 // Update the PC if we were asked to do so, but only do so if we find 578 // a breakpoint that we know about cause this could be a trap 579 // instruction in the code 580 if (pc_decrement > 0 && adjust_pc_if_needed) 581 reg_ctx_sp->SetPC(pc); 582 583 // If the breakpoint is for this thread, then we'll report the hit, 584 // but if it is for another thread, we can just report no reason. We 585 // don't need to worry about stepping over the breakpoint here, that 586 // will be taken care of when the thread resumes and notices that 587 // there's a breakpoint under the pc. If we have an operating system 588 // plug-in, we might have set a thread specific breakpoint using the 589 // operating system thread ID, so we can't make any assumptions about 590 // the thread ID so we must always report the breakpoint regardless 591 // of the thread. 592 if (bp_site_sp->ValidForThisThread(&thread) || 593 thread.GetProcess()->GetOperatingSystem() != NULL) 594 return StopInfo::CreateStopReasonWithBreakpointSiteID( 595 thread, bp_site_sp->GetID()); 596 else if (is_trace_if_actual_breakpoint_missing) 597 return StopInfo::CreateStopReasonToTrace(thread); 598 else 599 return StopInfoSP(); 600 } 601 602 // Don't call this a trace if we weren't single stepping this thread. 603 if (is_trace_if_actual_breakpoint_missing && 604 thread.GetTemporaryResumeState() == eStateStepping) { 605 return StopInfo::CreateStopReasonToTrace(thread); 606 } 607 } 608 } break; 609 610 case 7: // EXC_SYSCALL 611 case 8: // EXC_MACH_SYSCALL 612 case 9: // EXC_RPC_ALERT 613 case 10: // EXC_CRASH 614 break; 615 } 616 617 return StopInfoSP(new StopInfoMachException( 618 thread, exc_type, exc_data_count, exc_code, exc_sub_code)); 619 } 620 return StopInfoSP(); 621 } 622