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/Core/RegisterValue.h"
11 #include "lldb/Host/windows/HostThreadWindows.h"
12 #include "lldb/Host/windows/windows.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 "RegisterContext_x86.h"
19 #include "TargetThreadWindows.h"
20 #include "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
34 // lldb register sets are defined in terms of indices into the register array.
35 // As such, the
36 // order of RegisterInfos defined in global registers array must match the order
37 // defined here.
38 // When defining the register set layouts, these values can appear in an
39 // arbitrary order, and that
40 // determines the order that register values are displayed in a dump.
41 enum RegisterIndex {
42   eRegisterIndexEax,
43   eRegisterIndexEbx,
44   eRegisterIndexEcx,
45   eRegisterIndexEdx,
46   eRegisterIndexEdi,
47   eRegisterIndexEsi,
48   eRegisterIndexEbp,
49   eRegisterIndexEsp,
50   eRegisterIndexEip,
51   eRegisterIndexEflags
52 };
53 
54 // Array of all register information supported by Windows x86
55 RegisterInfo g_register_infos[] = {
56     //  Macro auto defines most stuff   eh_frame                DWARF
57     //  GENERIC                    GDB                   LLDB
58     //  VALUE REGS    INVALIDATE REGS
59     //  ==============================  =======================
60     //  ===================  =========================  ===================
61     //  =================  ==========    ===============
62     {DEFINE_GPR(eax, nullptr),
63      {ehframe_eax_i386, dwarf_eax_i386, LLDB_INVALID_REGNUM,
64       LLDB_INVALID_REGNUM, lldb_eax_i386},
65      nullptr,
66      nullptr,
67      nullptr,
68      0u},
69     {DEFINE_GPR(ebx, nullptr),
70      {ehframe_ebx_i386, dwarf_ebx_i386, LLDB_INVALID_REGNUM,
71       LLDB_INVALID_REGNUM, lldb_ebx_i386},
72      nullptr,
73      nullptr,
74      nullptr,
75      0u},
76     {DEFINE_GPR(ecx, nullptr),
77      {ehframe_ecx_i386, dwarf_ecx_i386, LLDB_INVALID_REGNUM,
78       LLDB_INVALID_REGNUM, lldb_ecx_i386},
79      nullptr,
80      nullptr,
81      nullptr,
82      0u},
83     {DEFINE_GPR(edx, nullptr),
84      {ehframe_edx_i386, dwarf_edx_i386, LLDB_INVALID_REGNUM,
85       LLDB_INVALID_REGNUM, lldb_edx_i386},
86      nullptr,
87      nullptr,
88      nullptr,
89      0u},
90     {DEFINE_GPR(edi, nullptr),
91      {ehframe_edi_i386, dwarf_edi_i386, LLDB_INVALID_REGNUM,
92       LLDB_INVALID_REGNUM, lldb_edi_i386},
93      nullptr,
94      nullptr,
95      nullptr,
96      0u},
97     {DEFINE_GPR(esi, nullptr),
98      {ehframe_esi_i386, dwarf_esi_i386, LLDB_INVALID_REGNUM,
99       LLDB_INVALID_REGNUM, lldb_esi_i386},
100      nullptr,
101      nullptr,
102      nullptr,
103      0u},
104     {DEFINE_GPR(ebp, "fp"),
105      {ehframe_ebp_i386, dwarf_ebp_i386, LLDB_REGNUM_GENERIC_FP,
106       LLDB_INVALID_REGNUM, lldb_ebp_i386},
107      nullptr,
108      nullptr,
109      nullptr,
110      0u},
111     {DEFINE_GPR(esp, "sp"),
112      {ehframe_esp_i386, dwarf_esp_i386, LLDB_REGNUM_GENERIC_SP,
113       LLDB_INVALID_REGNUM, lldb_esp_i386},
114      nullptr,
115      nullptr,
116      nullptr,
117      0u},
118     {DEFINE_GPR(eip, "pc"),
119      {ehframe_eip_i386, dwarf_eip_i386, LLDB_REGNUM_GENERIC_PC,
120       LLDB_INVALID_REGNUM, lldb_eip_i386},
121      nullptr,
122      nullptr,
123      nullptr,
124      0u},
125     {DEFINE_GPR_BIN(eflags, "flags"),
126      {ehframe_eflags_i386, dwarf_eflags_i386, LLDB_REGNUM_GENERIC_FLAGS,
127       LLDB_INVALID_REGNUM, lldb_eflags_i386},
128      nullptr,
129      nullptr,
130      nullptr,
131      0u},
132 };
133 static size_t k_num_register_infos = llvm::array_lengthof(g_register_infos);
134 
135 // Array of lldb register numbers used to define the set of all General Purpose
136 // Registers
137 uint32_t g_gpr_reg_indices[] = {eRegisterIndexEax, eRegisterIndexEbx,
138                                 eRegisterIndexEcx, eRegisterIndexEdx,
139                                 eRegisterIndexEdi, eRegisterIndexEsi,
140                                 eRegisterIndexEbp, eRegisterIndexEsp,
141                                 eRegisterIndexEip, eRegisterIndexEflags};
142 
143 RegisterSet g_register_sets[] = {
144     {"General Purpose Registers", "gpr",
145      llvm::array_lengthof(g_gpr_reg_indices), g_gpr_reg_indices},
146 };
147 }
148 
149 //------------------------------------------------------------------
150 // Constructors and Destructors
151 //------------------------------------------------------------------
152 RegisterContextWindows_x86::RegisterContextWindows_x86(
153     Thread &thread, uint32_t concrete_frame_idx)
154     : RegisterContextWindows(thread, concrete_frame_idx) {}
155 
156 RegisterContextWindows_x86::~RegisterContextWindows_x86() {}
157 
158 size_t RegisterContextWindows_x86::GetRegisterCount() {
159   return llvm::array_lengthof(g_register_infos);
160 }
161 
162 const RegisterInfo *
163 RegisterContextWindows_x86::GetRegisterInfoAtIndex(size_t reg) {
164   if (reg < k_num_register_infos)
165     return &g_register_infos[reg];
166   return NULL;
167 }
168 
169 size_t RegisterContextWindows_x86::GetRegisterSetCount() {
170   return llvm::array_lengthof(g_register_sets);
171 }
172 
173 const RegisterSet *RegisterContextWindows_x86::GetRegisterSet(size_t reg_set) {
174   return &g_register_sets[reg_set];
175 }
176 
177 bool RegisterContextWindows_x86::ReadRegister(const RegisterInfo *reg_info,
178                                               RegisterValue &reg_value) {
179   if (!CacheAllRegisterValues())
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 need
216   // to make sure
217   // our cached copy of the register values are fresh.  Otherwise when writing
218   // EAX, for example,
219   // we may also overwrite some other register with a stale value.
220   if (!CacheAllRegisterValues())
221     return false;
222 
223   Log *log = ProcessWindowsLog::GetLogIfAny(WINDOWS_LOG_REGISTERS);
224   uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
225   switch (reg) {
226   case lldb_eax_i386:
227     LLDB_LOG(log, "Write value {0:x} to EAX", reg_value.GetAsUInt32());
228     m_context.Eax = reg_value.GetAsUInt32();
229     break;
230   case lldb_ebx_i386:
231     LLDB_LOG(log, "Write value {0:x} to EBX", reg_value.GetAsUInt32());
232     m_context.Ebx = reg_value.GetAsUInt32();
233     break;
234   case lldb_ecx_i386:
235     LLDB_LOG(log, "Write value {0:x} to ECX", reg_value.GetAsUInt32());
236     m_context.Ecx = reg_value.GetAsUInt32();
237     break;
238   case lldb_edx_i386:
239     LLDB_LOG(log, "Write value {0:x} to EDX", reg_value.GetAsUInt32());
240     m_context.Edx = reg_value.GetAsUInt32();
241     break;
242   case lldb_edi_i386:
243     LLDB_LOG(log, "Write value {0:x} to EDI", reg_value.GetAsUInt32());
244     m_context.Edi = reg_value.GetAsUInt32();
245     break;
246   case lldb_esi_i386:
247     LLDB_LOG(log, "Write value {0:x} to ESI", reg_value.GetAsUInt32());
248     m_context.Esi = reg_value.GetAsUInt32();
249     break;
250   case lldb_ebp_i386:
251     LLDB_LOG(log, "Write value {0:x} to EBP", reg_value.GetAsUInt32());
252     m_context.Ebp = reg_value.GetAsUInt32();
253     break;
254   case lldb_esp_i386:
255     LLDB_LOG(log, "Write value {0:x} to ESP", reg_value.GetAsUInt32());
256     m_context.Esp = reg_value.GetAsUInt32();
257     break;
258   case lldb_eip_i386:
259     LLDB_LOG(log, "Write value {0:x} to EIP", reg_value.GetAsUInt32());
260     m_context.Eip = reg_value.GetAsUInt32();
261     break;
262   case lldb_eflags_i386:
263     LLDB_LOG(log, "Write value {0:x} to EFLAGS", reg_value.GetAsUInt32());
264     m_context.EFlags = reg_value.GetAsUInt32();
265     break;
266   default:
267     LLDB_LOG(log, "Write value {0:x} to unknown register {1}",
268              reg_value.GetAsUInt32(), reg);
269   }
270 
271   // Physically update the registers in the target process.
272   TargetThreadWindows &wthread = static_cast<TargetThreadWindows &>(m_thread);
273   return ::SetThreadContext(
274       wthread.GetHostThread().GetNativeThread().GetSystemHandle(), &m_context);
275 }
276 
277 bool RegisterContextWindows_x86::ReadRegisterHelper(
278     DWORD flags_required, const char *reg_name, DWORD value,
279     RegisterValue &reg_value) const {
280   Log *log = ProcessWindowsLog::GetLogIfAny(WINDOWS_LOG_REGISTERS);
281   if ((m_context.ContextFlags & flags_required) != flags_required) {
282     LLDB_LOG(log, "Thread context doesn't have {0}", reg_name);
283     return false;
284   }
285   LLDB_LOG(log, "Read value {0:x} from {1}", value, reg_name);
286   reg_value.SetUInt32(value);
287   return true;
288 }
289