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