1//===-- SBInstruction.cpp -------------------------------------------------===//
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 "lldb/Utility/Instrumentation.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/Host/HostInfo.h"
23#include "lldb/Host/StreamFile.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.
51class InstructionImpl {
52public:
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
61protected:
62  lldb::DisassemblerSP m_disasm_sp; // Can be empty/invalid
63  lldb::InstructionSP m_inst_sp;
64};
65
66using namespace lldb;
67using namespace lldb_private;
68
69SBInstruction::SBInstruction() { LLDB_INSTRUMENT_VA(this); }
70
71SBInstruction::SBInstruction(const lldb::DisassemblerSP &disasm_sp,
72                             const lldb::InstructionSP &inst_sp)
73    : m_opaque_sp(new InstructionImpl(disasm_sp, inst_sp)) {}
74
75SBInstruction::SBInstruction(const SBInstruction &rhs)
76    : m_opaque_sp(rhs.m_opaque_sp) {
77  LLDB_INSTRUMENT_VA(this, rhs);
78}
79
80const SBInstruction &SBInstruction::operator=(const SBInstruction &rhs) {
81  LLDB_INSTRUMENT_VA(this, rhs);
82
83  if (this != &rhs)
84    m_opaque_sp = rhs.m_opaque_sp;
85  return *this;
86}
87
88SBInstruction::~SBInstruction() = default;
89
90bool SBInstruction::IsValid() {
91  LLDB_INSTRUMENT_VA(this);
92  return this->operator bool();
93}
94SBInstruction::operator bool() const {
95  LLDB_INSTRUMENT_VA(this);
96
97  return m_opaque_sp && m_opaque_sp->IsValid();
98}
99
100SBAddress SBInstruction::GetAddress() {
101  LLDB_INSTRUMENT_VA(this);
102
103  SBAddress sb_addr;
104  lldb::InstructionSP inst_sp(GetOpaque());
105  if (inst_sp && inst_sp->GetAddress().IsValid())
106    sb_addr.SetAddress(inst_sp->GetAddress());
107  return sb_addr;
108}
109
110const char *SBInstruction::GetMnemonic(SBTarget target) {
111  LLDB_INSTRUMENT_VA(this, target);
112
113  lldb::InstructionSP inst_sp(GetOpaque());
114  if (!inst_sp)
115    return nullptr;
116
117  ExecutionContext exe_ctx;
118  TargetSP target_sp(target.GetSP());
119  std::unique_lock<std::recursive_mutex> lock;
120  if (target_sp) {
121    lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
122
123    target_sp->CalculateExecutionContext(exe_ctx);
124    exe_ctx.SetProcessSP(target_sp->GetProcessSP());
125  }
126  return ConstString(inst_sp->GetMnemonic(&exe_ctx)).GetCString();
127}
128
129const char *SBInstruction::GetOperands(SBTarget target) {
130  LLDB_INSTRUMENT_VA(this, target);
131
132  lldb::InstructionSP inst_sp(GetOpaque());
133  if (!inst_sp)
134    return nullptr;
135
136  ExecutionContext exe_ctx;
137  TargetSP target_sp(target.GetSP());
138  std::unique_lock<std::recursive_mutex> lock;
139  if (target_sp) {
140    lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
141
142    target_sp->CalculateExecutionContext(exe_ctx);
143    exe_ctx.SetProcessSP(target_sp->GetProcessSP());
144  }
145  return ConstString(inst_sp->GetOperands(&exe_ctx)).GetCString();
146}
147
148const char *SBInstruction::GetComment(SBTarget target) {
149  LLDB_INSTRUMENT_VA(this, target);
150
151  lldb::InstructionSP inst_sp(GetOpaque());
152  if (!inst_sp)
153    return nullptr;
154
155  ExecutionContext exe_ctx;
156  TargetSP target_sp(target.GetSP());
157  std::unique_lock<std::recursive_mutex> lock;
158  if (target_sp) {
159    lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
160
161    target_sp->CalculateExecutionContext(exe_ctx);
162    exe_ctx.SetProcessSP(target_sp->GetProcessSP());
163  }
164  return ConstString(inst_sp->GetComment(&exe_ctx)).GetCString();
165}
166
167lldb::InstructionControlFlowKind SBInstruction::GetControlFlowKind(lldb::SBTarget target) {
168  LLDB_INSTRUMENT_VA(this, target);
169
170  lldb::InstructionSP inst_sp(GetOpaque());
171  if (inst_sp) {
172    ExecutionContext exe_ctx;
173    TargetSP target_sp(target.GetSP());
174    std::unique_lock<std::recursive_mutex> lock;
175    if (target_sp) {
176      lock = std::unique_lock<std::recursive_mutex>(target_sp->GetAPIMutex());
177
178      target_sp->CalculateExecutionContext(exe_ctx);
179      exe_ctx.SetProcessSP(target_sp->GetProcessSP());
180    }
181    return inst_sp->GetControlFlowKind(&exe_ctx);
182  }
183  return lldb::eInstructionControlFlowKindUnknown;
184}
185
186size_t SBInstruction::GetByteSize() {
187  LLDB_INSTRUMENT_VA(this);
188
189  lldb::InstructionSP inst_sp(GetOpaque());
190  if (inst_sp)
191    return inst_sp->GetOpcode().GetByteSize();
192  return 0;
193}
194
195SBData SBInstruction::GetData(SBTarget target) {
196  LLDB_INSTRUMENT_VA(this, target);
197
198  lldb::SBData sb_data;
199  lldb::InstructionSP inst_sp(GetOpaque());
200  if (inst_sp) {
201    DataExtractorSP data_extractor_sp(new DataExtractor());
202    if (inst_sp->GetData(*data_extractor_sp)) {
203      sb_data.SetOpaque(data_extractor_sp);
204    }
205  }
206  return sb_data;
207}
208
209bool SBInstruction::DoesBranch() {
210  LLDB_INSTRUMENT_VA(this);
211
212  lldb::InstructionSP inst_sp(GetOpaque());
213  if (inst_sp)
214    return inst_sp->DoesBranch();
215  return false;
216}
217
218bool SBInstruction::HasDelaySlot() {
219  LLDB_INSTRUMENT_VA(this);
220
221  lldb::InstructionSP inst_sp(GetOpaque());
222  if (inst_sp)
223    return inst_sp->HasDelaySlot();
224  return false;
225}
226
227bool SBInstruction::CanSetBreakpoint() {
228  LLDB_INSTRUMENT_VA(this);
229
230  lldb::InstructionSP inst_sp(GetOpaque());
231  if (inst_sp)
232    return inst_sp->CanSetBreakpoint();
233  return false;
234}
235
236lldb::InstructionSP SBInstruction::GetOpaque() {
237  if (m_opaque_sp)
238    return m_opaque_sp->GetSP();
239  else
240    return lldb::InstructionSP();
241}
242
243void SBInstruction::SetOpaque(const lldb::DisassemblerSP &disasm_sp,
244                              const lldb::InstructionSP &inst_sp) {
245  m_opaque_sp = std::make_shared<InstructionImpl>(disasm_sp, inst_sp);
246}
247
248bool SBInstruction::GetDescription(lldb::SBStream &s) {
249  LLDB_INSTRUMENT_VA(this, s);
250
251  lldb::InstructionSP inst_sp(GetOpaque());
252  if (inst_sp) {
253    SymbolContext sc;
254    const Address &addr = inst_sp->GetAddress();
255    ModuleSP module_sp(addr.GetModule());
256    if (module_sp)
257      module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
258                                                sc);
259    // Use the "ref()" instead of the "get()" accessor in case the SBStream
260    // didn't have a stream already created, one will get created...
261    FormatEntity::Entry format;
262    FormatEntity::Parse("${addr}: ", format);
263    inst_sp->Dump(&s.ref(), 0, true, false, /*show_control_flow_kind=*/false,
264                  nullptr, &sc, nullptr, &format, 0);
265    return true;
266  }
267  return false;
268}
269
270void SBInstruction::Print(FILE *outp) {
271  LLDB_INSTRUMENT_VA(this, outp);
272  FileSP out = std::make_shared<NativeFile>(outp, /*take_ownership=*/false);
273  Print(out);
274}
275
276void SBInstruction::Print(SBFile out) {
277  LLDB_INSTRUMENT_VA(this, out);
278  Print(out.m_opaque_sp);
279}
280
281void SBInstruction::Print(FileSP out_sp) {
282  LLDB_INSTRUMENT_VA(this, out_sp);
283
284  if (!out_sp || !out_sp->IsValid())
285    return;
286
287  lldb::InstructionSP inst_sp(GetOpaque());
288  if (inst_sp) {
289    SymbolContext sc;
290    const Address &addr = inst_sp->GetAddress();
291    ModuleSP module_sp(addr.GetModule());
292    if (module_sp)
293      module_sp->ResolveSymbolContextForAddress(addr, eSymbolContextEverything,
294                                                sc);
295    StreamFile out_stream(out_sp);
296    FormatEntity::Entry format;
297    FormatEntity::Parse("${addr}: ", format);
298    inst_sp->Dump(&out_stream, 0, true, false, /*show_control_flow_kind=*/false,
299                  nullptr, &sc, nullptr, &format, 0);
300  }
301}
302
303bool SBInstruction::EmulateWithFrame(lldb::SBFrame &frame,
304                                     uint32_t evaluate_options) {
305  LLDB_INSTRUMENT_VA(this, frame, evaluate_options);
306
307  lldb::InstructionSP inst_sp(GetOpaque());
308  if (inst_sp) {
309    lldb::StackFrameSP frame_sp(frame.GetFrameSP());
310
311    if (frame_sp) {
312      lldb_private::ExecutionContext exe_ctx;
313      frame_sp->CalculateExecutionContext(exe_ctx);
314      lldb_private::Target *target = exe_ctx.GetTargetPtr();
315      lldb_private::ArchSpec arch = target->GetArchitecture();
316
317      return inst_sp->Emulate(
318          arch, evaluate_options, (void *)frame_sp.get(),
319          &lldb_private::EmulateInstruction::ReadMemoryFrame,
320          &lldb_private::EmulateInstruction::WriteMemoryFrame,
321          &lldb_private::EmulateInstruction::ReadRegisterFrame,
322          &lldb_private::EmulateInstruction::WriteRegisterFrame);
323    }
324  }
325  return false;
326}
327
328bool SBInstruction::DumpEmulation(const char *triple) {
329  LLDB_INSTRUMENT_VA(this, triple);
330
331  lldb::InstructionSP inst_sp(GetOpaque());
332  if (inst_sp && triple) {
333    return inst_sp->DumpEmulation(HostInfo::GetAugmentedArchSpec(triple));
334  }
335  return false;
336}
337
338bool SBInstruction::TestEmulation(lldb::SBStream &output_stream,
339                                  const char *test_file) {
340  LLDB_INSTRUMENT_VA(this, output_stream, test_file);
341
342  if (!m_opaque_sp)
343    SetOpaque(lldb::DisassemblerSP(),
344              lldb::InstructionSP(new PseudoInstruction()));
345
346  lldb::InstructionSP inst_sp(GetOpaque());
347  if (inst_sp)
348    return inst_sp->TestEmulation(output_stream.ref(), test_file);
349  return false;
350}
351