1 //===-- SBInstruction.cpp ---------------------------------------*- C++ -*-===//
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 "lldb/API/SBInstruction.h"
10 #include "SBReproducerPrivate.h"
11 
12 #include "lldb/API/SBAddress.h"
13 #include "lldb/API/SBFrame.h"
14 #include "lldb/API/SBFile.h"
15 
16 #include "lldb/API/SBInstruction.h"
17 #include "lldb/API/SBStream.h"
18 #include "lldb/API/SBTarget.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/ArchSpec.h"
28 #include "lldb/Utility/DataBufferHeap.h"
29 #include "lldb/Utility/DataExtractor.h"
30 
31 #include <memory>
32 
33 // We recently fixed a leak in one of the Instruction subclasses where the
34 // instruction will only hold a weak reference to the disassembler to avoid a
35 // cycle that was keeping both objects alive (leak) and we need the
36 // InstructionImpl class to make sure our public API behaves as users would
37 // expect. Calls in our public API allow clients to do things like:
38 //
39 // 1  lldb::SBInstruction inst;
40 // 2  inst = target.ReadInstructions(pc, 1).GetInstructionAtIndex(0)
41 // 3  if (inst.DoesBranch())
42 // 4  ...
43 //
44 // There was a temporary lldb::DisassemblerSP object created in the
45 // SBInstructionList that was returned by lldb.target.ReadInstructions() that
46 // will go away after line 2 but the "inst" object should be able to still
47 // answer questions about itself. So we make sure that any SBInstruction
48 // objects that are given out have a strong reference to the disassembler and
49 // the instruction so that the object can live and successfully respond to all
50 // queries.
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   LLDB_RECORD_CONSTRUCTOR_NO_ARGS(SBInstruction);
71 }
72 
73 SBInstruction::SBInstruction(const lldb::DisassemblerSP &disasm_sp,
74                              const lldb::InstructionSP &inst_sp)
75     : m_opaque_sp(new InstructionImpl(disasm_sp, inst_sp)) {}
76 
77 SBInstruction::SBInstruction(const SBInstruction &rhs)
78     : m_opaque_sp(rhs.m_opaque_sp) {
79   LLDB_RECORD_CONSTRUCTOR(SBInstruction, (const lldb::SBInstruction &), rhs);
80 }
81 
82 const SBInstruction &SBInstruction::operator=(const SBInstruction &rhs) {
83   LLDB_RECORD_METHOD(const lldb::SBInstruction &,
84                      SBInstruction, operator=,(const lldb::SBInstruction &),
85                      rhs);
86 
87   if (this != &rhs)
88     m_opaque_sp = rhs.m_opaque_sp;
89   return LLDB_RECORD_RESULT(*this);
90 }
91 
92 SBInstruction::~SBInstruction() {}
93 
94 bool SBInstruction::IsValid() {
95   LLDB_RECORD_METHOD_NO_ARGS(bool, SBInstruction, IsValid);
96   return this->operator bool();
97 }
98 SBInstruction::operator bool() const {
99   LLDB_RECORD_METHOD_CONST_NO_ARGS(bool, SBInstruction, operator bool);
100 
101   return m_opaque_sp && m_opaque_sp->IsValid();
102 }
103 
104 SBAddress SBInstruction::GetAddress() {
105   LLDB_RECORD_METHOD_NO_ARGS(lldb::SBAddress, SBInstruction, GetAddress);
106 
107   SBAddress sb_addr;
108   lldb::InstructionSP inst_sp(GetOpaque());
109   if (inst_sp && inst_sp->GetAddress().IsValid())
110     sb_addr.SetAddress(&inst_sp->GetAddress());
111   return LLDB_RECORD_RESULT(sb_addr);
112 }
113 
114 const char *SBInstruction::GetMnemonic(SBTarget target) {
115   LLDB_RECORD_METHOD(const char *, SBInstruction, GetMnemonic, (lldb::SBTarget),
116                      target);
117 
118   lldb::InstructionSP inst_sp(GetOpaque());
119   if (inst_sp) {
120     ExecutionContext exe_ctx;
121     TargetSP target_sp(target.GetSP());
122     std::unique_lock<std::recursive_mutex> lock;
123     if (target_sp) {
124       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
125 
126       target_sp->CalculateExecutionContext(exe_ctx);
127       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
128     }
129     return inst_sp->GetMnemonic(&exe_ctx);
130   }
131   return nullptr;
132 }
133 
134 const char *SBInstruction::GetOperands(SBTarget target) {
135   LLDB_RECORD_METHOD(const char *, SBInstruction, GetOperands, (lldb::SBTarget),
136                      target);
137 
138   lldb::InstructionSP inst_sp(GetOpaque());
139   if (inst_sp) {
140     ExecutionContext exe_ctx;
141     TargetSP target_sp(target.GetSP());
142     std::unique_lock<std::recursive_mutex> lock;
143     if (target_sp) {
144       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
145 
146       target_sp->CalculateExecutionContext(exe_ctx);
147       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
148     }
149     return inst_sp->GetOperands(&exe_ctx);
150   }
151   return nullptr;
152 }
153 
154 const char *SBInstruction::GetComment(SBTarget target) {
155   LLDB_RECORD_METHOD(const char *, SBInstruction, GetComment, (lldb::SBTarget),
156                      target);
157 
158   lldb::InstructionSP inst_sp(GetOpaque());
159   if (inst_sp) {
160     ExecutionContext exe_ctx;
161     TargetSP target_sp(target.GetSP());
162     std::unique_lock<std::recursive_mutex> lock;
163     if (target_sp) {
164       lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
165 
166       target_sp->CalculateExecutionContext(exe_ctx);
167       exe_ctx.SetProcessSP(target_sp->GetProcessSP());
168     }
169     return inst_sp->GetComment(&exe_ctx);
170   }
171   return nullptr;
172 }
173 
174 size_t SBInstruction::GetByteSize() {
175   LLDB_RECORD_METHOD_NO_ARGS(size_t, SBInstruction, GetByteSize);
176 
177   lldb::InstructionSP inst_sp(GetOpaque());
178   if (inst_sp)
179     return inst_sp->GetOpcode().GetByteSize();
180   return 0;
181 }
182 
183 SBData SBInstruction::GetData(SBTarget target) {
184   LLDB_RECORD_METHOD(lldb::SBData, SBInstruction, GetData, (lldb::SBTarget),
185                      target);
186 
187   lldb::SBData sb_data;
188   lldb::InstructionSP inst_sp(GetOpaque());
189   if (inst_sp) {
190     DataExtractorSP data_extractor_sp(new DataExtractor());
191     if (inst_sp->GetData(*data_extractor_sp)) {
192       sb_data.SetOpaque(data_extractor_sp);
193     }
194   }
195   return LLDB_RECORD_RESULT(sb_data);
196 }
197 
198 bool SBInstruction::DoesBranch() {
199   LLDB_RECORD_METHOD_NO_ARGS(bool, SBInstruction, DoesBranch);
200 
201   lldb::InstructionSP inst_sp(GetOpaque());
202   if (inst_sp)
203     return inst_sp->DoesBranch();
204   return false;
205 }
206 
207 bool SBInstruction::HasDelaySlot() {
208   LLDB_RECORD_METHOD_NO_ARGS(bool, SBInstruction, HasDelaySlot);
209 
210   lldb::InstructionSP inst_sp(GetOpaque());
211   if (inst_sp)
212     return inst_sp->HasDelaySlot();
213   return false;
214 }
215 
216 bool SBInstruction::CanSetBreakpoint() {
217   LLDB_RECORD_METHOD_NO_ARGS(bool, SBInstruction, CanSetBreakpoint);
218 
219   lldb::InstructionSP inst_sp(GetOpaque());
220   if (inst_sp)
221     return inst_sp->CanSetBreakpoint();
222   return false;
223 }
224 
225 lldb::InstructionSP SBInstruction::GetOpaque() {
226   if (m_opaque_sp)
227     return m_opaque_sp->GetSP();
228   else
229     return lldb::InstructionSP();
230 }
231 
232 void SBInstruction::SetOpaque(const lldb::DisassemblerSP &disasm_sp,
233                               const lldb::InstructionSP &inst_sp) {
234   m_opaque_sp = std::make_shared<InstructionImpl>(disasm_sp, inst_sp);
235 }
236 
237 bool SBInstruction::GetDescription(lldb::SBStream &s) {
238   LLDB_RECORD_METHOD(bool, SBInstruction, GetDescription, (lldb::SBStream &),
239                      s);
240 
241   lldb::InstructionSP inst_sp(GetOpaque());
242   if (inst_sp) {
243     SymbolContext sc;
244     const Address &addr = inst_sp->GetAddress();
245     ModuleSP module_sp(addr.GetModule());
246     if (module_sp)
247       module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
248                                                 sc);
249     // Use the "ref()" instead of the "get()" accessor in case the SBStream
250     // didn't have a stream already created, one will get created...
251     FormatEntity::Entry format;
252     FormatEntity::Parse("${addr}: ", format);
253     inst_sp->Dump(&s.ref(), 0, true, false, nullptr, &sc, nullptr, &format, 0);
254     return true;
255   }
256   return false;
257 }
258 
259 void SBInstruction::Print(FILE *outp) {
260   LLDB_RECORD_METHOD(void, SBInstruction, Print, (FILE *), outp);
261   FileSP out = std::make_shared<NativeFile>(outp, /*take_ownership=*/false);
262   Print(out);
263 }
264 
265 void SBInstruction::Print(SBFile out) {
266   LLDB_RECORD_METHOD(void, SBInstruction, Print, (SBFile), out);
267   Print(out.m_opaque_sp);
268 }
269 
270 void SBInstruction::Print(FileSP out_sp) {
271   LLDB_RECORD_METHOD(void, SBInstruction, Print, (FileSP), out_sp);
272 
273   if (!out_sp || !out_sp->IsValid())
274     return;
275 
276   lldb::InstructionSP inst_sp(GetOpaque());
277   if (inst_sp) {
278     SymbolContext sc;
279     const Address &addr = inst_sp->GetAddress();
280     ModuleSP module_sp(addr.GetModule());
281     if (module_sp)
282       module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
283                                                 sc);
284     StreamFile out_stream(out_sp);
285     FormatEntity::Entry format;
286     FormatEntity::Parse("${addr}: ", format);
287     inst_sp->Dump(&out_stream, 0, true, false, nullptr, &sc, nullptr, &format,
288                   0);
289   }
290 }
291 
292 bool SBInstruction::EmulateWithFrame(lldb::SBFrame &frame,
293                                      uint32_t evaluate_options) {
294   LLDB_RECORD_METHOD(bool, SBInstruction, EmulateWithFrame,
295                      (lldb::SBFrame &, uint32_t), frame, evaluate_options);
296 
297   lldb::InstructionSP inst_sp(GetOpaque());
298   if (inst_sp) {
299     lldb::StackFrameSP frame_sp(frame.GetFrameSP());
300 
301     if (frame_sp) {
302       lldb_private::ExecutionContext exe_ctx;
303       frame_sp->CalculateExecutionContext(exe_ctx);
304       lldb_private::Target *target = exe_ctx.GetTargetPtr();
305       lldb_private::ArchSpec arch = target->GetArchitecture();
306 
307       return inst_sp->Emulate(
308           arch, evaluate_options, (void *)frame_sp.get(),
309           &lldb_private::EmulateInstruction::ReadMemoryFrame,
310           &lldb_private::EmulateInstruction::WriteMemoryFrame,
311           &lldb_private::EmulateInstruction::ReadRegisterFrame,
312           &lldb_private::EmulateInstruction::WriteRegisterFrame);
313     }
314   }
315   return false;
316 }
317 
318 bool SBInstruction::DumpEmulation(const char *triple) {
319   LLDB_RECORD_METHOD(bool, SBInstruction, DumpEmulation, (const char *),
320                      triple);
321 
322   lldb::InstructionSP inst_sp(GetOpaque());
323   if (inst_sp && triple) {
324     return inst_sp->DumpEmulation(HostInfo::GetAugmentedArchSpec(triple));
325   }
326   return false;
327 }
328 
329 bool SBInstruction::TestEmulation(lldb::SBStream &output_stream,
330                                   const char *test_file) {
331   LLDB_RECORD_METHOD(bool, SBInstruction, TestEmulation,
332                      (lldb::SBStream &, const char *), output_stream,
333                      test_file);
334 
335   if (!m_opaque_sp)
336     SetOpaque(lldb::DisassemblerSP(),
337               lldb::InstructionSP(new PseudoInstruction()));
338 
339   lldb::InstructionSP inst_sp(GetOpaque());
340   if (inst_sp)
341     return inst_sp->TestEmulation(output_stream.get(), test_file);
342   return false;
343 }
344 
345 namespace lldb_private {
346 namespace repro {
347 
348 template <>
349 void RegisterMethods<SBInstruction>(Registry &R) {
350   LLDB_REGISTER_CONSTRUCTOR(SBInstruction, ());
351   LLDB_REGISTER_CONSTRUCTOR(SBInstruction, (const lldb::SBInstruction &));
352   LLDB_REGISTER_METHOD(
353       const lldb::SBInstruction &,
354       SBInstruction, operator=,(const lldb::SBInstruction &));
355   LLDB_REGISTER_METHOD(bool, SBInstruction, IsValid, ());
356   LLDB_REGISTER_METHOD_CONST(bool, SBInstruction, operator bool, ());
357   LLDB_REGISTER_METHOD(lldb::SBAddress, SBInstruction, GetAddress, ());
358   LLDB_REGISTER_METHOD(const char *, SBInstruction, GetMnemonic,
359                        (lldb::SBTarget));
360   LLDB_REGISTER_METHOD(const char *, SBInstruction, GetOperands,
361                        (lldb::SBTarget));
362   LLDB_REGISTER_METHOD(const char *, SBInstruction, GetComment,
363                        (lldb::SBTarget));
364   LLDB_REGISTER_METHOD(size_t, SBInstruction, GetByteSize, ());
365   LLDB_REGISTER_METHOD(lldb::SBData, SBInstruction, GetData,
366                        (lldb::SBTarget));
367   LLDB_REGISTER_METHOD(bool, SBInstruction, DoesBranch, ());
368   LLDB_REGISTER_METHOD(bool, SBInstruction, HasDelaySlot, ());
369   LLDB_REGISTER_METHOD(bool, SBInstruction, CanSetBreakpoint, ());
370   LLDB_REGISTER_METHOD(bool, SBInstruction, GetDescription,
371                        (lldb::SBStream &));
372   LLDB_REGISTER_METHOD(void, SBInstruction, Print, (FILE *));
373   LLDB_REGISTER_METHOD(void, SBInstruction, Print, (SBFile));
374   LLDB_REGISTER_METHOD(void, SBInstruction, Print, (FileSP));
375   LLDB_REGISTER_METHOD(bool, SBInstruction, EmulateWithFrame,
376                        (lldb::SBFrame &, uint32_t));
377   LLDB_REGISTER_METHOD(bool, SBInstruction, DumpEmulation, (const char *));
378   LLDB_REGISTER_METHOD(bool, SBInstruction, TestEmulation,
379                        (lldb::SBStream &, const char *));
380 }
381 
382 }
383 }
384