1 //===-- RegisterContextFreeBSDKernel_x86_64.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_x86_64.h"
10 
11 #include "lldb/Target/Process.h"
12 #include "lldb/Target/Thread.h"
13 #include "lldb/Utility/RegisterValue.h"
14 #include "llvm/Support/Endian.h"
15 
16 using namespace lldb;
17 using namespace lldb_private;
18 
19 RegisterContextFreeBSDKernel_x86_64::RegisterContextFreeBSDKernel_x86_64(
20     Thread &thread, RegisterInfoInterface *register_info, lldb::addr_t pcb_addr)
21     : RegisterContextPOSIX_x86(thread, 0, register_info), m_pcb_addr(pcb_addr) {
22 }
23 
24 bool RegisterContextFreeBSDKernel_x86_64::ReadGPR() { return true; }
25 
26 bool RegisterContextFreeBSDKernel_x86_64::ReadFPR() { return true; }
27 
28 bool RegisterContextFreeBSDKernel_x86_64::WriteGPR() {
29   assert(0);
30   return false;
31 }
32 
33 bool RegisterContextFreeBSDKernel_x86_64::WriteFPR() {
34   assert(0);
35   return false;
36 }
37 
38 bool RegisterContextFreeBSDKernel_x86_64::ReadRegister(
39     const RegisterInfo *reg_info, RegisterValue &value) {
40   if (m_pcb_addr == LLDB_INVALID_ADDRESS)
41     return false;
42 
43   struct {
44     llvm::support::ulittle64_t r15;
45     llvm::support::ulittle64_t r14;
46     llvm::support::ulittle64_t r13;
47     llvm::support::ulittle64_t r12;
48     llvm::support::ulittle64_t rbp;
49     llvm::support::ulittle64_t rsp;
50     llvm::support::ulittle64_t rbx;
51     llvm::support::ulittle64_t rip;
52   } pcb;
53 
54   Status error;
55   size_t rd =
56       m_thread.GetProcess()->ReadMemory(m_pcb_addr, &pcb, sizeof(pcb), error);
57   if (rd != sizeof(pcb))
58     return false;
59 
60   uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];
61   switch (reg) {
62 #define REG(x)                                                                 \
63   case lldb_##x##_x86_64:                                                      \
64     value = pcb.x;                                                             \
65     break;
66 
67     REG(r15);
68     REG(r14);
69     REG(r13);
70     REG(r12);
71     REG(rbp);
72     REG(rsp);
73     REG(rbx);
74     REG(rip);
75 
76 #undef REG
77 
78   default:
79     return false;
80   }
81 
82   return true;
83 }
84 
85 bool RegisterContextFreeBSDKernel_x86_64::WriteRegister(
86     const RegisterInfo *reg_info, const RegisterValue &value) {
87   return false;
88 }
89