1 //===-- RegisterContextWindows_x86.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/Host/windows/HostThreadWindows.h"
11 #include "lldb/Host/windows/windows.h"
12 #include "lldb/Utility/RegisterValue.h"
13 #include "lldb/Utility/Status.h"
14 #include "lldb/lldb-private-types.h"
15 
16 #include "ProcessWindowsLog.h"
17 #include "RegisterContextWindows_x86.h"
18 #include "Plugins/Process/Utility/RegisterContext_x86.h"
19 #include "TargetThreadWindows.h"
20 #include "Plugins/Process/Utility/lldb-x86-register-enums.h"
21 
22 #include "llvm/ADT/STLExtras.h"
23 
24 using namespace lldb;
25 using namespace lldb_private;
26 
27 #define DEFINE_GPR(reg, alt) #reg, alt, 4, 0, eEncodingUint, eFormatHexUppercase
28 #define DEFINE_GPR_BIN(reg, alt) #reg, alt, 4, 0, eEncodingUint, eFormatBinary
29 
30 namespace {
31 
32 // This enum defines the layout of the global RegisterInfo array.  This is
33 // necessary because lldb register sets are defined in terms of indices into
34 // the register array. As such, the order of RegisterInfos defined in global
35 // registers array must match the order defined here. When defining the
36 // register set layouts, these values can appear in an arbitrary order, and
37 // that determines the order that register values are displayed in a dump.
38 enum RegisterIndex {
39   eRegisterIndexEax,
40   eRegisterIndexEbx,
41   eRegisterIndexEcx,
42   eRegisterIndexEdx,
43   eRegisterIndexEdi,
44   eRegisterIndexEsi,
45   eRegisterIndexEbp,
46   eRegisterIndexEsp,
47   eRegisterIndexEip,
48   eRegisterIndexEflags
49 };
50 
51 // Array of all register information supported by Windows x86
52 RegisterInfo g_register_infos[] = {
53     //  Macro auto defines most stuff   eh_frame                DWARF
54     //  GENERIC                    GDB                   LLDB
55     //  VALUE REGS    INVALIDATE REGS
56     //  ==============================  =======================
57     //  ===================  =========================  ===================
58     //  =================  ==========    ===============
59     {DEFINE_GPR(eax, nullptr),
60      {ehframe_eax_i386, dwarf_eax_i386, LLDB_INVALID_REGNUM,
61       LLDB_INVALID_REGNUM, lldb_eax_i386},
62      nullptr,
63      nullptr,
64      nullptr,
65      0u},
66     {DEFINE_GPR(ebx, nullptr),
67      {ehframe_ebx_i386, dwarf_ebx_i386, LLDB_INVALID_REGNUM,
68       LLDB_INVALID_REGNUM, lldb_ebx_i386},
69      nullptr,
70      nullptr,
71      nullptr,
72      0u},
73     {DEFINE_GPR(ecx, nullptr),
74      {ehframe_ecx_i386, dwarf_ecx_i386, LLDB_INVALID_REGNUM,
75       LLDB_INVALID_REGNUM, lldb_ecx_i386},
76      nullptr,
77      nullptr,
78      nullptr,
79      0u},
80     {DEFINE_GPR(edx, nullptr),
81      {ehframe_edx_i386, dwarf_edx_i386, LLDB_INVALID_REGNUM,
82       LLDB_INVALID_REGNUM, lldb_edx_i386},
83      nullptr,
84      nullptr,
85      nullptr,
86      0u},
87     {DEFINE_GPR(edi, nullptr),
88      {ehframe_edi_i386, dwarf_edi_i386, LLDB_INVALID_REGNUM,
89       LLDB_INVALID_REGNUM, lldb_edi_i386},
90      nullptr,
91      nullptr,
92      nullptr,
93      0u},
94     {DEFINE_GPR(esi, nullptr),
95      {ehframe_esi_i386, dwarf_esi_i386, LLDB_INVALID_REGNUM,
96       LLDB_INVALID_REGNUM, lldb_esi_i386},
97      nullptr,
98      nullptr,
99      nullptr,
100      0u},
101     {DEFINE_GPR(ebp, "fp"),
102      {ehframe_ebp_i386, dwarf_ebp_i386, LLDB_REGNUM_GENERIC_FP,
103       LLDB_INVALID_REGNUM, lldb_ebp_i386},
104      nullptr,
105      nullptr,
106      nullptr,
107      0u},
108     {DEFINE_GPR(esp, "sp"),
109      {ehframe_esp_i386, dwarf_esp_i386, LLDB_REGNUM_GENERIC_SP,
110       LLDB_INVALID_REGNUM, lldb_esp_i386},
111      nullptr,
112      nullptr,
113      nullptr,
114      0u},
115     {DEFINE_GPR(eip, "pc"),
116      {ehframe_eip_i386, dwarf_eip_i386, LLDB_REGNUM_GENERIC_PC,
117       LLDB_INVALID_REGNUM, lldb_eip_i386},
118      nullptr,
119      nullptr,
120      nullptr,
121      0u},
122     {DEFINE_GPR_BIN(eflags, "flags"),
123      {ehframe_eflags_i386, dwarf_eflags_i386, LLDB_REGNUM_GENERIC_FLAGS,
124       LLDB_INVALID_REGNUM, lldb_eflags_i386},
125      nullptr,
126      nullptr,
127      nullptr,
128      0u},
129 };
130 static size_t k_num_register_infos = llvm::array_lengthof(g_register_infos);
131 
132 // Array of lldb register numbers used to define the set of all General Purpose
133 // Registers
134 uint32_t g_gpr_reg_indices[] = {eRegisterIndexEax, eRegisterIndexEbx,
135                                 eRegisterIndexEcx, eRegisterIndexEdx,
136                                 eRegisterIndexEdi, eRegisterIndexEsi,
137                                 eRegisterIndexEbp, eRegisterIndexEsp,
138                                 eRegisterIndexEip, eRegisterIndexEflags};
139 
140 RegisterSet g_register_sets[] = {
141     {"General Purpose Registers", "gpr",
142      llvm::array_lengthof(g_gpr_reg_indices), g_gpr_reg_indices},
143 };
144 }
145 
146 //------------------------------------------------------------------
147 // Constructors and Destructors
148 //------------------------------------------------------------------
149 RegisterContextWindows_x86::RegisterContextWindows_x86(
150     Thread &thread, uint32_t concrete_frame_idx)
151     : RegisterContextWindows(thread, concrete_frame_idx) {}
152 
153 RegisterContextWindows_x86::~RegisterContextWindows_x86() {}
154 
155 size_t RegisterContextWindows_x86::GetRegisterCount() {
156   return llvm::array_lengthof(g_register_infos);
157 }
158 
159 const RegisterInfo *
160 RegisterContextWindows_x86::GetRegisterInfoAtIndex(size_t reg) {
161   if (reg < k_num_register_infos)
162     return &g_register_infos[reg];
163   return NULL;
164 }
165 
166 size_t RegisterContextWindows_x86::GetRegisterSetCount() {
167   return llvm::array_lengthof(g_register_sets);
168 }
169 
170 const RegisterSet *RegisterContextWindows_x86::GetRegisterSet(size_t reg_set) {
171   return &g_register_sets[reg_set];
172 }
173 
174 bool RegisterContextWindows_x86::ReadRegister(const RegisterInfo *reg_info,
175                                               RegisterValue &reg_value) {
176   if (!CacheAllRegisterValues())
177     return false;
178 
179   if (reg_info == nullptr)
180     return false;
181 
182   uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
183   switch (reg) {
184   case lldb_eax_i386:
185     return ReadRegisterHelper(CONTEXT_INTEGER, "EAX", m_context.Eax, reg_value);
186   case lldb_ebx_i386:
187     return ReadRegisterHelper(CONTEXT_INTEGER, "EBX", m_context.Ebx, reg_value);
188   case lldb_ecx_i386:
189     return ReadRegisterHelper(CONTEXT_INTEGER, "ECX", m_context.Ecx, reg_value);
190   case lldb_edx_i386:
191     return ReadRegisterHelper(CONTEXT_INTEGER, "EDX", m_context.Edx, reg_value);
192   case lldb_edi_i386:
193     return ReadRegisterHelper(CONTEXT_INTEGER, "EDI", m_context.Edi, reg_value);
194   case lldb_esi_i386:
195     return ReadRegisterHelper(CONTEXT_INTEGER, "ESI", m_context.Esi, reg_value);
196   case lldb_ebp_i386:
197     return ReadRegisterHelper(CONTEXT_CONTROL, "EBP", m_context.Ebp, reg_value);
198   case lldb_esp_i386:
199     return ReadRegisterHelper(CONTEXT_CONTROL, "ESP", m_context.Esp, reg_value);
200   case lldb_eip_i386:
201     return ReadRegisterHelper(CONTEXT_CONTROL, "EIP", m_context.Eip, reg_value);
202   case lldb_eflags_i386:
203     return ReadRegisterHelper(CONTEXT_CONTROL, "EFLAGS", m_context.EFlags,
204                               reg_value);
205   default:
206     Log *log = ProcessWindowsLog::GetLogIfAny(WINDOWS_LOG_REGISTERS);
207     LLDB_LOG(log, "Requested unknown register {0}", reg);
208     break;
209   }
210   return false;
211 }
212 
213 bool RegisterContextWindows_x86::WriteRegister(const RegisterInfo *reg_info,
214                                                const RegisterValue &reg_value) {
215   // Since we cannot only write a single register value to the inferior, we
216   // need to make sure our cached copy of the register values are fresh.
217   // Otherwise when writing EAX, for example, we may also overwrite some other
218   // register with a stale value.
219   if (!CacheAllRegisterValues())
220     return false;
221 
222   Log *log = ProcessWindowsLog::GetLogIfAny(WINDOWS_LOG_REGISTERS);
223   uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
224   switch (reg) {
225   case lldb_eax_i386:
226     LLDB_LOG(log, "Write value {0:x} to EAX", reg_value.GetAsUInt32());
227     m_context.Eax = reg_value.GetAsUInt32();
228     break;
229   case lldb_ebx_i386:
230     LLDB_LOG(log, "Write value {0:x} to EBX", reg_value.GetAsUInt32());
231     m_context.Ebx = reg_value.GetAsUInt32();
232     break;
233   case lldb_ecx_i386:
234     LLDB_LOG(log, "Write value {0:x} to ECX", reg_value.GetAsUInt32());
235     m_context.Ecx = reg_value.GetAsUInt32();
236     break;
237   case lldb_edx_i386:
238     LLDB_LOG(log, "Write value {0:x} to EDX", reg_value.GetAsUInt32());
239     m_context.Edx = reg_value.GetAsUInt32();
240     break;
241   case lldb_edi_i386:
242     LLDB_LOG(log, "Write value {0:x} to EDI", reg_value.GetAsUInt32());
243     m_context.Edi = reg_value.GetAsUInt32();
244     break;
245   case lldb_esi_i386:
246     LLDB_LOG(log, "Write value {0:x} to ESI", reg_value.GetAsUInt32());
247     m_context.Esi = reg_value.GetAsUInt32();
248     break;
249   case lldb_ebp_i386:
250     LLDB_LOG(log, "Write value {0:x} to EBP", reg_value.GetAsUInt32());
251     m_context.Ebp = reg_value.GetAsUInt32();
252     break;
253   case lldb_esp_i386:
254     LLDB_LOG(log, "Write value {0:x} to ESP", reg_value.GetAsUInt32());
255     m_context.Esp = reg_value.GetAsUInt32();
256     break;
257   case lldb_eip_i386:
258     LLDB_LOG(log, "Write value {0:x} to EIP", reg_value.GetAsUInt32());
259     m_context.Eip = reg_value.GetAsUInt32();
260     break;
261   case lldb_eflags_i386:
262     LLDB_LOG(log, "Write value {0:x} to EFLAGS", reg_value.GetAsUInt32());
263     m_context.EFlags = reg_value.GetAsUInt32();
264     break;
265   default:
266     LLDB_LOG(log, "Write value {0:x} to unknown register {1}",
267              reg_value.GetAsUInt32(), reg);
268   }
269 
270   // Physically update the registers in the target process.
271   TargetThreadWindows &wthread = static_cast<TargetThreadWindows &>(m_thread);
272   return ::SetThreadContext(
273       wthread.GetHostThread().GetNativeThread().GetSystemHandle(), &m_context);
274 }
275 
276 bool RegisterContextWindows_x86::ReadRegisterHelper(
277     DWORD flags_required, const char *reg_name, DWORD value,
278     RegisterValue &reg_value) const {
279   Log *log = ProcessWindowsLog::GetLogIfAny(WINDOWS_LOG_REGISTERS);
280   if ((m_context.ContextFlags & flags_required) != flags_required) {
281     LLDB_LOG(log, "Thread context doesn't have {0}", reg_name);
282     return false;
283   }
284   LLDB_LOG(log, "Read value {0:x} from {1}", value, reg_name);
285   reg_value.SetUInt32(value);
286   return true;
287 }
288