xref: /llvm-project/lldb/source/Commands/CommandObjectDisassemble.cpp (revision 1cbd1b8f692df7742efb9114510688045d901f96)
1 //===-- CommandObjectDisassemble.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 "CommandObjectDisassemble.h"
10 #include "lldb/Core/AddressRange.h"
11 #include "lldb/Core/Disassembler.h"
12 #include "lldb/Core/Module.h"
13 #include "lldb/Host/OptionParser.h"
14 #include "lldb/Interpreter/CommandInterpreter.h"
15 #include "lldb/Interpreter/CommandReturnObject.h"
16 #include "lldb/Interpreter/OptionArgParser.h"
17 #include "lldb/Interpreter/Options.h"
18 #include "lldb/Symbol/Function.h"
19 #include "lldb/Symbol/Symbol.h"
20 #include "lldb/Target/SectionLoadList.h"
21 #include "lldb/Target/StackFrame.h"
22 #include "lldb/Target/Target.h"
23 
24 #define DEFAULT_DISASM_BYTE_SIZE 32
25 #define DEFAULT_DISASM_NUM_INS 4
26 
27 using namespace lldb;
28 using namespace lldb_private;
29 
30 #define LLDB_OPTIONS_disassemble
31 #include "CommandOptions.inc"
32 
33 CommandObjectDisassemble::CommandOptions::CommandOptions()
34     : Options(), num_lines_context(0), num_instructions(0), func_name(),
35       current_function(false), start_addr(), end_addr(), at_pc(false),
36       frame_line(false), plugin_name(), flavor_string(), arch(),
37       some_location_specified(false), symbol_containing_addr() {
38   OptionParsingStarting(nullptr);
39 }
40 
41 CommandObjectDisassemble::CommandOptions::~CommandOptions() = default;
42 
43 Status CommandObjectDisassemble::CommandOptions::SetOptionValue(
44     uint32_t option_idx, llvm::StringRef option_arg,
45     ExecutionContext *execution_context) {
46   Status error;
47 
48   const int short_option = m_getopt_table[option_idx].val;
49 
50   switch (short_option) {
51   case 'm':
52     show_mixed = true;
53     break;
54 
55   case 'C':
56     if (option_arg.getAsInteger(0, num_lines_context))
57       error.SetErrorStringWithFormat("invalid num context lines string: \"%s\"",
58                                      option_arg.str().c_str());
59     break;
60 
61   case 'c':
62     if (option_arg.getAsInteger(0, num_instructions))
63       error.SetErrorStringWithFormat(
64           "invalid num of instructions string: \"%s\"",
65           option_arg.str().c_str());
66     break;
67 
68   case 'b':
69     show_bytes = true;
70     break;
71 
72   case 's': {
73     start_addr = OptionArgParser::ToAddress(execution_context, option_arg,
74                                             LLDB_INVALID_ADDRESS, &error);
75     if (start_addr != LLDB_INVALID_ADDRESS)
76       some_location_specified = true;
77   } break;
78   case 'e': {
79     end_addr = OptionArgParser::ToAddress(execution_context, option_arg,
80                                           LLDB_INVALID_ADDRESS, &error);
81     if (end_addr != LLDB_INVALID_ADDRESS)
82       some_location_specified = true;
83   } break;
84 
85   case 'n':
86     func_name.assign(std::string(option_arg));
87     some_location_specified = true;
88     break;
89 
90   case 'p':
91     at_pc = true;
92     some_location_specified = true;
93     break;
94 
95   case 'l':
96     frame_line = true;
97     // Disassemble the current source line kind of implies showing mixed source
98     // code context.
99     show_mixed = true;
100     some_location_specified = true;
101     break;
102 
103   case 'P':
104     plugin_name.assign(std::string(option_arg));
105     break;
106 
107   case 'F': {
108     TargetSP target_sp =
109         execution_context ? execution_context->GetTargetSP() : TargetSP();
110     if (target_sp && (target_sp->GetArchitecture().GetTriple().getArch() ==
111                           llvm::Triple::x86 ||
112                       target_sp->GetArchitecture().GetTriple().getArch() ==
113                           llvm::Triple::x86_64)) {
114       flavor_string.assign(std::string(option_arg));
115     } else
116       error.SetErrorStringWithFormat("Disassembler flavors are currently only "
117                                      "supported for x86 and x86_64 targets.");
118     break;
119   }
120 
121   case 'r':
122     raw = true;
123     break;
124 
125   case 'f':
126     current_function = true;
127     some_location_specified = true;
128     break;
129 
130   case 'A':
131     if (execution_context) {
132       const auto &target_sp = execution_context->GetTargetSP();
133       auto platform_ptr = target_sp ? target_sp->GetPlatform().get() : nullptr;
134       arch = Platform::GetAugmentedArchSpec(platform_ptr, option_arg);
135     }
136     break;
137 
138   case 'a': {
139     symbol_containing_addr = OptionArgParser::ToAddress(
140         execution_context, option_arg, LLDB_INVALID_ADDRESS, &error);
141     if (symbol_containing_addr != LLDB_INVALID_ADDRESS) {
142       some_location_specified = true;
143     }
144   } break;
145 
146   default:
147     llvm_unreachable("Unimplemented option");
148   }
149 
150   return error;
151 }
152 
153 void CommandObjectDisassemble::CommandOptions::OptionParsingStarting(
154     ExecutionContext *execution_context) {
155   show_mixed = false;
156   show_bytes = false;
157   num_lines_context = 0;
158   num_instructions = 0;
159   func_name.clear();
160   current_function = false;
161   at_pc = false;
162   frame_line = false;
163   start_addr = LLDB_INVALID_ADDRESS;
164   end_addr = LLDB_INVALID_ADDRESS;
165   symbol_containing_addr = LLDB_INVALID_ADDRESS;
166   raw = false;
167   plugin_name.clear();
168 
169   Target *target =
170       execution_context ? execution_context->GetTargetPtr() : nullptr;
171 
172   // This is a hack till we get the ability to specify features based on
173   // architecture.  For now GetDisassemblyFlavor is really only valid for x86
174   // (and for the llvm assembler plugin, but I'm papering over that since that
175   // is the only disassembler plugin we have...
176   if (target) {
177     if (target->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86 ||
178         target->GetArchitecture().GetTriple().getArch() ==
179             llvm::Triple::x86_64) {
180       flavor_string.assign(target->GetDisassemblyFlavor());
181     } else
182       flavor_string.assign("default");
183 
184   } else
185     flavor_string.assign("default");
186 
187   arch.Clear();
188   some_location_specified = false;
189 }
190 
191 Status CommandObjectDisassemble::CommandOptions::OptionParsingFinished(
192     ExecutionContext *execution_context) {
193   if (!some_location_specified)
194     current_function = true;
195   return Status();
196 }
197 
198 llvm::ArrayRef<OptionDefinition>
199 CommandObjectDisassemble::CommandOptions::GetDefinitions() {
200   return llvm::makeArrayRef(g_disassemble_options);
201 }
202 
203 // CommandObjectDisassemble
204 
205 CommandObjectDisassemble::CommandObjectDisassemble(
206     CommandInterpreter &interpreter)
207     : CommandObjectParsed(
208           interpreter, "disassemble",
209           "Disassemble specified instructions in the current target.  "
210           "Defaults to the current function for the current thread and "
211           "stack frame.",
212           "disassemble [<cmd-options>]", eCommandRequiresTarget),
213       m_options() {}
214 
215 CommandObjectDisassemble::~CommandObjectDisassemble() = default;
216 
217 llvm::Expected<std::vector<AddressRange>>
218 CommandObjectDisassemble::GetContainingAddressRanges() {
219   std::vector<AddressRange> ranges;
220   const auto &get_range = [&](Address addr) {
221     ModuleSP module_sp(addr.GetModule());
222     SymbolContext sc;
223     bool resolve_tail_call_address = true;
224     addr.GetModule()->ResolveSymbolContextForAddress(
225         addr, eSymbolContextEverything, sc, resolve_tail_call_address);
226     if (sc.function || sc.symbol) {
227       AddressRange range;
228       sc.GetAddressRange(eSymbolContextFunction | eSymbolContextSymbol, 0,
229                          false, range);
230       ranges.push_back(range);
231     }
232   };
233 
234   Target &target = GetSelectedTarget();
235   if (!target.GetSectionLoadList().IsEmpty()) {
236     Address symbol_containing_address;
237     if (target.GetSectionLoadList().ResolveLoadAddress(
238             m_options.symbol_containing_addr, symbol_containing_address)) {
239       get_range(symbol_containing_address);
240     }
241   } else {
242     for (lldb::ModuleSP module_sp : target.GetImages().Modules()) {
243       Address file_address;
244       if (module_sp->ResolveFileAddress(m_options.symbol_containing_addr,
245                                         file_address)) {
246         get_range(file_address);
247       }
248     }
249   }
250 
251   if (ranges.empty()) {
252     return llvm::createStringError(
253         llvm::inconvertibleErrorCode(),
254         "Could not find function bounds for address 0x%" PRIx64,
255         m_options.symbol_containing_addr);
256   }
257   return ranges;
258 }
259 
260 llvm::Expected<std::vector<AddressRange>>
261 CommandObjectDisassemble::GetCurrentFunctionRanges() {
262   StackFrame *frame = m_exe_ctx.GetFramePtr();
263   if (!frame) {
264     return llvm::createStringError(llvm::inconvertibleErrorCode(),
265                                    "Cannot disassemble around the current "
266                                    "function without a selected frame.\n");
267   }
268   SymbolContext sc(
269       frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextSymbol));
270   AddressRange range;
271   if (sc.function)
272     range = sc.function->GetAddressRange();
273   else if (sc.symbol && sc.symbol->ValueIsAddress()) {
274     range = {sc.symbol->GetAddress(), sc.symbol->GetByteSize()};
275   } else
276     range = {frame->GetFrameCodeAddress(), DEFAULT_DISASM_BYTE_SIZE};
277 
278   return std::vector<AddressRange>{range};
279 }
280 
281 llvm::Expected<std::vector<AddressRange>>
282 CommandObjectDisassemble::GetCurrentLineRanges() {
283   StackFrame *frame = m_exe_ctx.GetFramePtr();
284   if (!frame) {
285     return llvm::createStringError(llvm::inconvertibleErrorCode(),
286                                    "Cannot disassemble around the current "
287                                    "line without a selected frame.\n");
288   }
289 
290   LineEntry pc_line_entry(
291       frame->GetSymbolContext(eSymbolContextLineEntry).line_entry);
292   if (pc_line_entry.IsValid())
293     return std::vector<AddressRange>{pc_line_entry.range};
294 
295   // No line entry, so just disassemble around the current pc
296   m_options.show_mixed = false;
297   return GetPCRanges();
298 }
299 
300 llvm::Expected<std::vector<AddressRange>>
301 CommandObjectDisassemble::GetNameRanges() {
302   ConstString name(m_options.func_name.c_str());
303   const bool include_symbols = true;
304   const bool include_inlines = true;
305 
306   // Find functions matching the given name.
307   SymbolContextList sc_list;
308   GetSelectedTarget().GetImages().FindFunctions(
309       name, eFunctionNameTypeAuto, include_symbols, include_inlines, sc_list);
310 
311   std::vector<AddressRange> ranges;
312   AddressRange range;
313   const uint32_t scope =
314       eSymbolContextBlock | eSymbolContextFunction | eSymbolContextSymbol;
315   const bool use_inline_block_range = true;
316   for (SymbolContext sc : sc_list.SymbolContexts()) {
317     for (uint32_t range_idx = 0;
318          sc.GetAddressRange(scope, range_idx, use_inline_block_range, range);
319          ++range_idx) {
320       ranges.push_back(range);
321     }
322   }
323   if (ranges.empty()) {
324     return llvm::createStringError(llvm::inconvertibleErrorCode(),
325                                    "Unable to find symbol with name '%s'.\n",
326                                    name.GetCString());
327   }
328   return ranges;
329 }
330 
331 llvm::Expected<std::vector<AddressRange>>
332 CommandObjectDisassemble::GetPCRanges() {
333   StackFrame *frame = m_exe_ctx.GetFramePtr();
334   if (!frame) {
335     return llvm::createStringError(llvm::inconvertibleErrorCode(),
336                                    "Cannot disassemble around the current "
337                                    "PC without a selected frame.\n");
338   }
339 
340   if (m_options.num_instructions == 0) {
341     // Disassembling at the PC always disassembles some number of
342     // instructions (not the whole function).
343     m_options.num_instructions = DEFAULT_DISASM_NUM_INS;
344   }
345   return std::vector<AddressRange>{{frame->GetFrameCodeAddress(), 0}};
346 }
347 
348 llvm::Expected<std::vector<AddressRange>>
349 CommandObjectDisassemble::GetStartEndAddressRanges() {
350   addr_t size = 0;
351   if (m_options.end_addr != LLDB_INVALID_ADDRESS) {
352     if (m_options.end_addr <= m_options.start_addr) {
353       return llvm::createStringError(llvm::inconvertibleErrorCode(),
354                                      "End address before start address.");
355     }
356     size = m_options.end_addr - m_options.start_addr;
357   }
358   return std::vector<AddressRange>{{Address(m_options.start_addr), size}};
359 }
360 
361 llvm::Expected<std::vector<AddressRange>>
362 CommandObjectDisassemble::GetRangesForSelectedMode() {
363   if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS)
364     return CommandObjectDisassemble::GetContainingAddressRanges();
365   if (m_options.current_function)
366     return CommandObjectDisassemble::GetCurrentFunctionRanges();
367   if (m_options.frame_line)
368     return CommandObjectDisassemble::GetCurrentLineRanges();
369   if (!m_options.func_name.empty())
370     return CommandObjectDisassemble::GetNameRanges();
371   if (m_options.start_addr != LLDB_INVALID_ADDRESS)
372     return CommandObjectDisassemble::GetStartEndAddressRanges();
373   return CommandObjectDisassemble::GetPCRanges();
374 }
375 
376 bool CommandObjectDisassemble::DoExecute(Args &command,
377                                          CommandReturnObject &result) {
378   Target *target = &GetSelectedTarget();
379 
380   if (!m_options.arch.IsValid())
381     m_options.arch = target->GetArchitecture();
382 
383   if (!m_options.arch.IsValid()) {
384     result.AppendError(
385         "use the --arch option or set the target architecture to disassemble");
386     result.SetStatus(eReturnStatusFailed);
387     return false;
388   }
389 
390   const char *plugin_name = m_options.GetPluginName();
391   const char *flavor_string = m_options.GetFlavorString();
392 
393   DisassemblerSP disassembler =
394       Disassembler::FindPlugin(m_options.arch, flavor_string, plugin_name);
395 
396   if (!disassembler) {
397     if (plugin_name) {
398       result.AppendErrorWithFormat(
399           "Unable to find Disassembler plug-in named '%s' that supports the "
400           "'%s' architecture.\n",
401           plugin_name, m_options.arch.GetArchitectureName());
402     } else
403       result.AppendErrorWithFormat(
404           "Unable to find Disassembler plug-in for the '%s' architecture.\n",
405           m_options.arch.GetArchitectureName());
406     result.SetStatus(eReturnStatusFailed);
407     return false;
408   } else if (flavor_string != nullptr && !disassembler->FlavorValidForArchSpec(
409                                              m_options.arch, flavor_string))
410     result.AppendWarningWithFormat(
411         "invalid disassembler flavor \"%s\", using default.\n", flavor_string);
412 
413   result.SetStatus(eReturnStatusSuccessFinishResult);
414 
415   if (!command.empty()) {
416     result.AppendErrorWithFormat(
417         "\"disassemble\" arguments are specified as options.\n");
418     const int terminal_width =
419         GetCommandInterpreter().GetDebugger().GetTerminalWidth();
420     GetOptions()->GenerateOptionUsage(result.GetErrorStream(), this,
421                                       terminal_width);
422     result.SetStatus(eReturnStatusFailed);
423     return false;
424   }
425 
426   if (m_options.show_mixed && m_options.num_lines_context == 0)
427     m_options.num_lines_context = 2;
428 
429   // Always show the PC in the disassembly
430   uint32_t options = Disassembler::eOptionMarkPCAddress;
431 
432   // Mark the source line for the current PC only if we are doing mixed source
433   // and assembly
434   if (m_options.show_mixed)
435     options |= Disassembler::eOptionMarkPCSourceLine;
436 
437   if (m_options.show_bytes)
438     options |= Disassembler::eOptionShowBytes;
439 
440   if (m_options.raw)
441     options |= Disassembler::eOptionRawOuput;
442 
443   llvm::Expected<std::vector<AddressRange>> ranges = GetRangesForSelectedMode();
444   if (!ranges) {
445     result.AppendError(toString(ranges.takeError()));
446     result.SetStatus(eReturnStatusFailed);
447     return result.Succeeded();
448   }
449 
450   bool print_sc_header = ranges->size() > 1;
451   for (AddressRange cur_range : *ranges) {
452     Disassembler::Limit limit;
453     if (m_options.num_instructions == 0) {
454       limit = {Disassembler::Limit::Bytes, cur_range.GetByteSize()};
455       if (limit.value == 0)
456         limit.value = DEFAULT_DISASM_BYTE_SIZE;
457     } else {
458       limit = {Disassembler::Limit::Instructions, m_options.num_instructions};
459     }
460     if (Disassembler::Disassemble(
461             GetDebugger(), m_options.arch, plugin_name, flavor_string,
462             m_exe_ctx, cur_range.GetBaseAddress(), limit, m_options.show_mixed,
463             m_options.show_mixed ? m_options.num_lines_context : 0, options,
464             result.GetOutputStream())) {
465       result.SetStatus(eReturnStatusSuccessFinishResult);
466     } else {
467       if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS) {
468         result.AppendErrorWithFormat(
469             "Failed to disassemble memory in function at 0x%8.8" PRIx64 ".\n",
470             m_options.symbol_containing_addr);
471       } else {
472         result.AppendErrorWithFormat(
473             "Failed to disassemble memory at 0x%8.8" PRIx64 ".\n",
474             cur_range.GetBaseAddress().GetLoadAddress(target));
475       }
476       result.SetStatus(eReturnStatusFailed);
477     }
478     if (print_sc_header)
479       result.AppendMessage("\n");
480   }
481 
482   return result.Succeeded();
483 }
484