1 //===-- SBInstruction.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/API/SBInstruction.h"
11 
12 #include "lldb/API/SBAddress.h"
13 #include "lldb/API/SBFrame.h"
14 #include "lldb/API/SBInstruction.h"
15 #include "lldb/API/SBStream.h"
16 #include "lldb/API/SBTarget.h"
17 
18 #include "lldb/Core/ArchSpec.h"
19 #include "lldb/Core/Disassembler.h"
20 #include "lldb/Core/EmulateInstruction.h"
21 #include "lldb/Core/Module.h"
22 #include "lldb/Core/StreamFile.h"
23 #include "lldb/Host/HostInfo.h"
24 #include "lldb/Target/ExecutionContext.h"
25 #include "lldb/Target/StackFrame.h"
26 #include "lldb/Target/Target.h"
27 #include "lldb/Utility/DataBufferHeap.h"
28 #include "lldb/Utility/DataExtractor.h"
29 
30 //----------------------------------------------------------------------
31 // We recently fixed a leak in one of the Instruction subclasses where
32 // the instruction will only hold a weak reference to the disassembler
33 // to avoid a cycle that was keeping both objects alive (leak) and we
34 // need the InstructionImpl class to make sure our public API behaves
35 // as users would expect. Calls in our public API allow clients to do
36 // things like:
37 //
38 // 1  lldb::SBInstruction inst;
39 // 2  inst = target.ReadInstructions(pc, 1).GetInstructionAtIndex(0)
40 // 3  if (inst.DoesBranch())
41 // 4  ...
42 //
43 // There was a temporary lldb::DisassemblerSP object created in the
44 // SBInstructionList that was returned by lldb.target.ReadInstructions()
45 // that will go away after line 2 but the "inst" object should be able
46 // to still answer questions about itself. So we make sure that any
47 // SBInstruction objects that are given out have a strong reference to
48 // the disassembler and the instruction so that the object can live and
49 // successfully respond to all queries.
50 //----------------------------------------------------------------------
51 class InstructionImpl {
52 public:
53   InstructionImpl(const lldb::DisassemblerSP &disasm_sp,
54                   const lldb::InstructionSP &inst_sp)
55       : m_disasm_sp(disasm_sp), m_inst_sp(inst_sp) {}
56 
57   lldb::InstructionSP GetSP() const { return m_inst_sp; }
58 
59   bool IsValid() const { return (bool)m_inst_sp; }
60 
61 protected:
62   lldb::DisassemblerSP m_disasm_sp; // Can be empty/invalid
63   lldb::InstructionSP m_inst_sp;
64 };
65 
66 using namespace lldb;
67 using namespace lldb_private;
68 
69 SBInstruction::SBInstruction() : m_opaque_sp() {}
70 
71 SBInstruction::SBInstruction(const lldb::DisassemblerSP &disasm_sp,
72                              const lldb::InstructionSP &inst_sp)
73     : m_opaque_sp(new InstructionImpl(disasm_sp, inst_sp)) {}
74 
75 SBInstruction::SBInstruction(const SBInstruction &rhs)
76     : m_opaque_sp(rhs.m_opaque_sp) {}
77 
78 const SBInstruction &SBInstruction::operator=(const SBInstruction &rhs) {
79   if (this != &rhs)
80     m_opaque_sp = rhs.m_opaque_sp;
81   return *this;
82 }
83 
84 SBInstruction::~SBInstruction() {}
85 
86 bool SBInstruction::IsValid() { return m_opaque_sp && m_opaque_sp->IsValid(); }
87 
88 SBAddress SBInstruction::GetAddress() {
89   SBAddress sb_addr;
90   lldb::InstructionSP inst_sp(GetOpaque());
91   if (inst_sp && inst_sp->GetAddress().IsValid())
92     sb_addr.SetAddress(&inst_sp->GetAddress());
93   return sb_addr;
94 }
95 
96 const char *SBInstruction::GetMnemonic(SBTarget target) {
97   lldb::InstructionSP inst_sp(GetOpaque());
98   if (inst_sp) {
99     ExecutionContext exe_ctx;
100     TargetSP target_sp(target.GetSP());
101     std::unique_lock<std::recursive_mutex> lock;
102     if (target_sp) {
103       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
104 
105       target_sp->CalculateExecutionContext(exe_ctx);
106       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
107     }
108     return inst_sp->GetMnemonic(&exe_ctx);
109   }
110   return NULL;
111 }
112 
113 const char *SBInstruction::GetOperands(SBTarget target) {
114   lldb::InstructionSP inst_sp(GetOpaque());
115   if (inst_sp) {
116     ExecutionContext exe_ctx;
117     TargetSP target_sp(target.GetSP());
118     std::unique_lock<std::recursive_mutex> lock;
119     if (target_sp) {
120       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
121 
122       target_sp->CalculateExecutionContext(exe_ctx);
123       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
124     }
125     return inst_sp->GetOperands(&exe_ctx);
126   }
127   return NULL;
128 }
129 
130 const char *SBInstruction::GetComment(SBTarget target) {
131   lldb::InstructionSP inst_sp(GetOpaque());
132   if (inst_sp) {
133     ExecutionContext exe_ctx;
134     TargetSP target_sp(target.GetSP());
135     std::unique_lock<std::recursive_mutex> lock;
136     if (target_sp) {
137       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
138 
139       target_sp->CalculateExecutionContext(exe_ctx);
140       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
141     }
142     return inst_sp->GetComment(&exe_ctx);
143   }
144   return NULL;
145 }
146 
147 size_t SBInstruction::GetByteSize() {
148   lldb::InstructionSP inst_sp(GetOpaque());
149   if (inst_sp)
150     return inst_sp->GetOpcode().GetByteSize();
151   return 0;
152 }
153 
154 SBData SBInstruction::GetData(SBTarget target) {
155   lldb::SBData sb_data;
156   lldb::InstructionSP inst_sp(GetOpaque());
157   if (inst_sp) {
158     DataExtractorSP data_extractor_sp(new DataExtractor());
159     if (inst_sp->GetData(*data_extractor_sp)) {
160       sb_data.SetOpaque(data_extractor_sp);
161     }
162   }
163   return sb_data;
164 }
165 
166 bool SBInstruction::DoesBranch() {
167   lldb::InstructionSP inst_sp(GetOpaque());
168   if (inst_sp)
169     return inst_sp->DoesBranch();
170   return false;
171 }
172 
173 bool SBInstruction::HasDelaySlot() {
174   lldb::InstructionSP inst_sp(GetOpaque());
175   if (inst_sp)
176     return inst_sp->HasDelaySlot();
177   return false;
178 }
179 
180 bool SBInstruction::CanSetBreakpoint () {
181   lldb::InstructionSP inst_sp(GetOpaque());
182   if (inst_sp)
183     return inst_sp->CanSetBreakpoint();
184   return false;
185 }
186 
187 lldb::InstructionSP SBInstruction::GetOpaque() {
188   if (m_opaque_sp)
189     return m_opaque_sp->GetSP();
190   else
191     return lldb::InstructionSP();
192 }
193 
194 void SBInstruction::SetOpaque(const lldb::DisassemblerSP &disasm_sp,
195                               const lldb::InstructionSP &inst_sp) {
196   m_opaque_sp.reset(new InstructionImpl(disasm_sp, inst_sp));
197 }
198 
199 bool SBInstruction::GetDescription(lldb::SBStream &s) {
200   lldb::InstructionSP inst_sp(GetOpaque());
201   if (inst_sp) {
202     SymbolContext sc;
203     const Address &addr = inst_sp->GetAddress();
204     ModuleSP module_sp(addr.GetModule());
205     if (module_sp)
206       module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
207                                                 sc);
208     // Use the "ref()" instead of the "get()" accessor in case the SBStream
209     // didn't have a stream already created, one will get created...
210     FormatEntity::Entry format;
211     FormatEntity::Parse("${addr}: ", format);
212     inst_sp->Dump(&s.ref(), 0, true, false, NULL, &sc, NULL, &format, 0);
213     return true;
214   }
215   return false;
216 }
217 
218 void SBInstruction::Print(FILE *out) {
219   if (out == NULL)
220     return;
221 
222   lldb::InstructionSP inst_sp(GetOpaque());
223   if (inst_sp) {
224     SymbolContext sc;
225     const Address &addr = inst_sp->GetAddress();
226     ModuleSP module_sp(addr.GetModule());
227     if (module_sp)
228       module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
229                                                 sc);
230     StreamFile out_stream(out, false);
231     FormatEntity::Entry format;
232     FormatEntity::Parse("${addr}: ", format);
233     inst_sp->Dump(&out_stream, 0, true, false, NULL, &sc, NULL, &format, 0);
234   }
235 }
236 
237 bool SBInstruction::EmulateWithFrame(lldb::SBFrame &frame,
238                                      uint32_t evaluate_options) {
239   lldb::InstructionSP inst_sp(GetOpaque());
240   if (inst_sp) {
241     lldb::StackFrameSP frame_sp(frame.GetFrameSP());
242 
243     if (frame_sp) {
244       lldb_private::ExecutionContext exe_ctx;
245       frame_sp->CalculateExecutionContext(exe_ctx);
246       lldb_private::Target *target = exe_ctx.GetTargetPtr();
247       lldb_private::ArchSpec arch = target->GetArchitecture();
248 
249       return inst_sp->Emulate(
250           arch, evaluate_options, (void *)frame_sp.get(),
251           &lldb_private::EmulateInstruction::ReadMemoryFrame,
252           &lldb_private::EmulateInstruction::WriteMemoryFrame,
253           &lldb_private::EmulateInstruction::ReadRegisterFrame,
254           &lldb_private::EmulateInstruction::WriteRegisterFrame);
255     }
256   }
257   return false;
258 }
259 
260 bool SBInstruction::DumpEmulation(const char *triple) {
261   lldb::InstructionSP inst_sp(GetOpaque());
262   if (inst_sp && triple) {
263     return inst_sp->DumpEmulation(HostInfo::GetAugmentedArchSpec(triple));
264   }
265   return false;
266 }
267 
268 bool SBInstruction::TestEmulation(lldb::SBStream &output_stream,
269                                   const char *test_file) {
270   if (!m_opaque_sp)
271     SetOpaque(lldb::DisassemblerSP(),
272               lldb::InstructionSP(new PseudoInstruction()));
273 
274   lldb::InstructionSP inst_sp(GetOpaque());
275   if (inst_sp)
276     return inst_sp->TestEmulation(output_stream.get(), test_file);
277   return false;
278 }
279 
280 lldb::AddressClass SBInstruction::GetAddressClass() {
281   lldb::InstructionSP inst_sp(GetOpaque());
282   if (inst_sp)
283     return inst_sp->GetAddressClass();
284   return eAddressClassInvalid;
285 }
286