llvm/lldb/source/Plugins/Process/Utility/StopInfoMachException.cpp

//===-- StopInfoMachException.cpp -----------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "StopInfoMachException.h"

#include "lldb/lldb-forward.h"

#if defined(__APPLE__)
// Needed for the EXC_RESOURCE interpretation macros
#include <kern/exc_resource.h>
#endif

#include "lldb/Breakpoint/Watchpoint.h"
#include "lldb/Symbol/Symbol.h"
#include "lldb/Target/ABI.h"
#include "lldb/Target/DynamicLoader.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Target/UnixSignals.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/StreamString.h"
#include <optional>

usingnamespacelldb;
usingnamespacelldb_private;

/// Information about a pointer-authentication related instruction.
struct PtrauthInstructionInfo { … };

/// Get any pointer-authentication related information about the instruction
/// at address \p at_addr.
static std::optional<PtrauthInstructionInfo>
GetPtrauthInstructionInfo(Target &target, const ArchSpec &arch,
                          const Address &at_addr) { … }

/// Describe the load address of \p addr using the format filename:line:col.
static void DescribeAddressBriefly(Stream &strm, const Address &addr,
                                   Target &target) { … }

bool StopInfoMachException::DeterminePtrauthFailure(ExecutionContext &exe_ctx) { … }

const char *StopInfoMachException::GetDescription() { … }

static StopInfoSP GetStopInfoForHardwareBP(Thread &thread, Target *target,
                                           uint32_t exc_data_count,
                                           uint64_t exc_sub_code,
                                           uint64_t exc_sub_sub_code) { … }

#if defined(__APPLE__)
const char *
StopInfoMachException::MachException::Name(exception_type_t exc_type) {
  switch (exc_type) {
  case EXC_BAD_ACCESS:
    return "EXC_BAD_ACCESS";
  case EXC_BAD_INSTRUCTION:
    return "EXC_BAD_INSTRUCTION";
  case EXC_ARITHMETIC:
    return "EXC_ARITHMETIC";
  case EXC_EMULATION:
    return "EXC_EMULATION";
  case EXC_SOFTWARE:
    return "EXC_SOFTWARE";
  case EXC_BREAKPOINT:
    return "EXC_BREAKPOINT";
  case EXC_SYSCALL:
    return "EXC_SYSCALL";
  case EXC_MACH_SYSCALL:
    return "EXC_MACH_SYSCALL";
  case EXC_RPC_ALERT:
    return "EXC_RPC_ALERT";
#ifdef EXC_CRASH
  case EXC_CRASH:
    return "EXC_CRASH";
#endif
  case EXC_RESOURCE:
    return "EXC_RESOURCE";
#ifdef EXC_GUARD
  case EXC_GUARD:
    return "EXC_GUARD";
#endif
#ifdef EXC_CORPSE_NOTIFY
  case EXC_CORPSE_NOTIFY:
    return "EXC_CORPSE_NOTIFY";
#endif
#ifdef EXC_CORPSE_VARIANT_BIT
  case EXC_CORPSE_VARIANT_BIT:
    return "EXC_CORPSE_VARIANT_BIT";
#endif
  default:
    break;
  }
  return NULL;
}

std::optional<exception_type_t>
StopInfoMachException::MachException::ExceptionCode(const char *name) {
  return llvm::StringSwitch<std::optional<exception_type_t>>(name)
      .Case("EXC_BAD_ACCESS", EXC_BAD_ACCESS)
      .Case("EXC_BAD_INSTRUCTION", EXC_BAD_INSTRUCTION)
      .Case("EXC_ARITHMETIC", EXC_ARITHMETIC)
      .Case("EXC_EMULATION", EXC_EMULATION)
      .Case("EXC_SOFTWARE", EXC_SOFTWARE)
      .Case("EXC_BREAKPOINT", EXC_BREAKPOINT)
      .Case("EXC_SYSCALL", EXC_SYSCALL)
      .Case("EXC_MACH_SYSCALL", EXC_MACH_SYSCALL)
      .Case("EXC_RPC_ALERT", EXC_RPC_ALERT)
#ifdef EXC_CRASH
      .Case("EXC_CRASH", EXC_CRASH)
#endif
      .Case("EXC_RESOURCE", EXC_RESOURCE)
#ifdef EXC_GUARD
      .Case("EXC_GUARD", EXC_GUARD)
#endif
#ifdef EXC_CORPSE_NOTIFY
      .Case("EXC_CORPSE_NOTIFY", EXC_CORPSE_NOTIFY)
#endif
      .Default(std::nullopt);
}
#endif

StopInfoSP StopInfoMachException::CreateStopReasonWithMachException(
    Thread &thread, uint32_t exc_type, uint32_t exc_data_count,
    uint64_t exc_code, uint64_t exc_sub_code, uint64_t exc_sub_sub_code,
    bool pc_already_adjusted, bool adjust_pc_if_needed) { … }

// Detect an unusual situation on Darwin where:
//
//   0. We did an instruction-step before this.
//   1. We have a hardware breakpoint or watchpoint set.
//   2. We resumed the process, but not with an instruction-step.
//   3. The thread gets an "instruction-step completed" mach exception.
//   4. The pc has not advanced - it is the same as before.
//
// This method returns true for that combination of events.
bool StopInfoMachException::WasContinueInterrupted(Thread &thread) { … }