lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_arm64.cpp

   1 //===-- RegisterContextFreeBSDKernel_arm64.cpp ----------------------------===//
   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 #include "RegisterContextFreeBSDKernel_arm64.h"
  10 #include "Plugins/Process/Utility/lldb-arm64-register-enums.h"
  11
  12 #include "lldb/Target/Process.h"
  13 #include "lldb/Target/Thread.h"
  14 #include "lldb/Utility/RegisterValue.h"
  15 #include "llvm/Support/Endian.h"
  16
  17 using namespace lldb;
  18 using namespace lldb_private;
  19
  20 RegisterContextFreeBSDKernel_arm64::RegisterContextFreeBSDKernel_arm64(
  21     Thread &thread, std::unique_ptr<RegisterInfoPOSIX_arm64> register_info_up,
  22     lldb::addr_t pcb_addr)
  23     : RegisterContextPOSIX_arm64(thread, std::move(register_info_up)),
  24       m_pcb_addr(pcb_addr) {}
  25
  26 bool RegisterContextFreeBSDKernel_arm64::ReadGPR() { return true; }
  27
  28 bool RegisterContextFreeBSDKernel_arm64::ReadFPR() { return true; }
  29
  30 bool RegisterContextFreeBSDKernel_arm64::WriteGPR() {
  31   assert(0);
  32   return false;
  33 }
  34
  35 bool RegisterContextFreeBSDKernel_arm64::WriteFPR() {
  36   assert(0);
  37   return false;
  38 }
  39
  40 bool RegisterContextFreeBSDKernel_arm64::ReadRegister(
  41     const RegisterInfo *reg_info, RegisterValue &value) {
  42   if (m_pcb_addr == LLDB_INVALID_ADDRESS)
  43     return false;
  44
  45   struct {
  46     llvm::support::ulittle64_t x[30];
  47     llvm::support::ulittle64_t lr;
  48     llvm::support::ulittle64_t _reserved;
  49     llvm::support::ulittle64_t sp;
  50   } pcb;
  51
  52   Status error;
  53   size_t rd =
  54       m_thread.GetProcess()->ReadMemory(m_pcb_addr, &pcb, sizeof(pcb), error);
  55   if (rd != sizeof(pcb))
  56     return false;
  57
  58   uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];
  59   switch (reg) {
  60   case gpr_x0_arm64:
  61   case gpr_x1_arm64:
  62   case gpr_x2_arm64:
  63   case gpr_x3_arm64:
  64   case gpr_x4_arm64:
  65   case gpr_x5_arm64:
  66   case gpr_x6_arm64:
  67   case gpr_x7_arm64:
  68   case gpr_x8_arm64:
  69   case gpr_x9_arm64:
  70   case gpr_x10_arm64:
  71   case gpr_x11_arm64:
  72   case gpr_x12_arm64:
  73   case gpr_x13_arm64:
  74   case gpr_x14_arm64:
  75   case gpr_x15_arm64:
  76   case gpr_x16_arm64:
  77   case gpr_x17_arm64:
  78   case gpr_x18_arm64:
  79   case gpr_x19_arm64:
  80   case gpr_x20_arm64:
  81   case gpr_x21_arm64:
  82   case gpr_x22_arm64:
  83   case gpr_x23_arm64:
  84   case gpr_x24_arm64:
  85   case gpr_x25_arm64:
  86   case gpr_x26_arm64:
  87   case gpr_x27_arm64:
  88   case gpr_x28_arm64:
  89   case gpr_fp_arm64:
  90     static_assert(gpr_fp_arm64 - gpr_x0_arm64 == 29,
  91                   "nonconsecutive arm64 register numbers");
  92     value = pcb.x[reg - gpr_x0_arm64];
  93     break;
  94   case gpr_sp_arm64:
  95     value = pcb.sp;
  96     break;
  97   case gpr_pc_arm64:
  98     // The pc of crashing thread is stored in lr.
  99     value = pcb.lr;
 100     break;
 101   default:
 102     return false;
 103   }
 104   return true;
 105 }
 106
 107 bool RegisterContextFreeBSDKernel_arm64::WriteRegister(
 108     const RegisterInfo *reg_info, const RegisterValue &value) {
 109   return false;
 110 }