1 //===-- CommandObjectDisassemble.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 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 // Project includes
14 #include "CommandObjectDisassemble.h"
15 #include "lldb/Core/AddressRange.h"
16 #include "lldb/Core/Disassembler.h"
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/SourceManager.h"
19 #include "lldb/Host/StringConvert.h"
20 #include "lldb/Interpreter/CommandCompletions.h"
21 #include "lldb/Interpreter/CommandInterpreter.h"
22 #include "lldb/Interpreter/CommandReturnObject.h"
23 #include "lldb/Interpreter/Options.h"
24 #include "lldb/Symbol/Function.h"
25 #include "lldb/Symbol/Symbol.h"
26 #include "lldb/Target/Process.h"
27 #include "lldb/Target/SectionLoadList.h"
28 #include "lldb/Target/StackFrame.h"
29 #include "lldb/Target/Target.h"
30 
31 #define DEFAULT_DISASM_BYTE_SIZE 32
32 #define DEFAULT_DISASM_NUM_INS  4
33 
34 using namespace lldb;
35 using namespace lldb_private;
36 
37 CommandObjectDisassemble::CommandOptions::CommandOptions() :
38     Options(),
39     num_lines_context(0),
40     num_instructions (0),
41     func_name(),
42     current_function (false),
43     start_addr(),
44     end_addr (),
45     at_pc (false),
46     frame_line (false),
47     plugin_name (),
48     flavor_string(),
49     arch(),
50     some_location_specified (false),
51     symbol_containing_addr ()
52 {
53     OptionParsingStarting(nullptr);
54 }
55 
56 CommandObjectDisassemble::CommandOptions::~CommandOptions() = default;
57 
58 Error
59 CommandObjectDisassemble::CommandOptions::SetOptionValue(uint32_t option_idx,
60                                                          const char *option_arg,
61                                             ExecutionContext *execution_context)
62 {
63     Error error;
64 
65     const int short_option = m_getopt_table[option_idx].val;
66 
67     bool success;
68 
69     switch (short_option)
70     {
71     case 'm':
72         show_mixed = true;
73         break;
74 
75     case 'C':
76         num_lines_context = StringConvert::ToUInt32(option_arg, 0, 0, &success);
77         if (!success)
78             error.SetErrorStringWithFormat ("invalid num context lines string: \"%s\"", option_arg);
79         break;
80 
81     case 'c':
82         num_instructions = StringConvert::ToUInt32(option_arg, 0, 0, &success);
83         if (!success)
84             error.SetErrorStringWithFormat ("invalid num of instructions string: \"%s\"", option_arg);
85         break;
86 
87     case 'b':
88         show_bytes = true;
89         break;
90 
91     case 's':
92         {
93             start_addr = Args::StringToAddress(execution_context, option_arg,
94                                                LLDB_INVALID_ADDRESS, &error);
95             if (start_addr != LLDB_INVALID_ADDRESS)
96                 some_location_specified = true;
97         }
98         break;
99     case 'e':
100         {
101             end_addr = Args::StringToAddress(execution_context, option_arg,
102                                              LLDB_INVALID_ADDRESS, &error);
103             if (end_addr != LLDB_INVALID_ADDRESS)
104                 some_location_specified = true;
105         }
106         break;
107 
108     case 'n':
109         func_name.assign (option_arg);
110         some_location_specified = true;
111         break;
112 
113     case 'p':
114         at_pc = true;
115         some_location_specified = true;
116         break;
117 
118     case 'l':
119         frame_line = true;
120         // Disassemble the current source line kind of implies showing mixed
121         // source code context.
122         show_mixed = true;
123         some_location_specified = true;
124         break;
125 
126     case 'P':
127         plugin_name.assign (option_arg);
128         break;
129 
130     case 'F':
131         {
132             TargetSP target_sp = execution_context ?
133                 execution_context->GetTargetSP() : TargetSP();
134             if (target_sp &&
135                 (target_sp->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86
136                 || target_sp->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86_64))
137             {
138                 flavor_string.assign (option_arg);
139             }
140             else
141                 error.SetErrorStringWithFormat("Disassembler flavors are currently only supported for x86 and x86_64 targets.");
142             break;
143         }
144 
145     case 'r':
146         raw = true;
147         break;
148 
149     case 'f':
150         current_function = true;
151         some_location_specified = true;
152         break;
153 
154     case 'A':
155         if (execution_context)
156         {
157             auto target_sp = execution_context ?
158                 execution_context->GetTargetSP() : TargetSP();
159             auto platform_sp =
160                 target_sp ? target_sp->GetPlatform() : PlatformSP();
161             if (!arch.SetTriple (option_arg, platform_sp.get()))
162                 arch.SetTriple (option_arg);
163         }
164         break;
165 
166     case 'a':
167         {
168             symbol_containing_addr =
169                 Args::StringToAddress(execution_context,option_arg,
170                                       LLDB_INVALID_ADDRESS, &error);
171             if (symbol_containing_addr != LLDB_INVALID_ADDRESS)
172             {
173                 some_location_specified = true;
174             }
175         }
176         break;
177 
178     default:
179         error.SetErrorStringWithFormat("unrecognized short option '%c'", short_option);
180         break;
181     }
182 
183     return error;
184 }
185 
186 void
187 CommandObjectDisassemble::CommandOptions::OptionParsingStarting(
188                                             ExecutionContext *execution_context)
189 {
190     show_mixed = false;
191     show_bytes = false;
192     num_lines_context = 0;
193     num_instructions = 0;
194     func_name.clear();
195     current_function = false;
196     at_pc = false;
197     frame_line = false;
198     start_addr = LLDB_INVALID_ADDRESS;
199     end_addr = LLDB_INVALID_ADDRESS;
200     symbol_containing_addr = LLDB_INVALID_ADDRESS;
201     raw = false;
202     plugin_name.clear();
203 
204     Target *target =
205         execution_context ? execution_context->GetTargetPtr() : nullptr;
206 
207     // This is a hack till we get the ability to specify features based on architecture.  For now GetDisassemblyFlavor
208     // is really only valid for x86 (and for the llvm assembler plugin, but I'm papering over that since that is the
209     // only disassembler plugin we have...
210     if (target)
211     {
212         if (target->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86
213             || target->GetArchitecture().GetTriple().getArch() == llvm::Triple::x86_64)
214         {
215             flavor_string.assign(target->GetDisassemblyFlavor());
216         }
217         else
218             flavor_string.assign ("default");
219 
220     }
221     else
222         flavor_string.assign("default");
223 
224     arch.Clear();
225     some_location_specified = false;
226 }
227 
228 Error
229 CommandObjectDisassemble::CommandOptions::OptionParsingFinished(
230                                             ExecutionContext *execution_context)
231 {
232     if (!some_location_specified)
233         current_function = true;
234     return Error();
235 }
236 
237 const OptionDefinition*
238 CommandObjectDisassemble::CommandOptions::GetDefinitions ()
239 {
240     return g_option_table;
241 }
242 
243 OptionDefinition
244 CommandObjectDisassemble::CommandOptions::g_option_table[] =
245 {
246 { LLDB_OPT_SET_ALL, false, "bytes"        , 'b', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Show opcode bytes when disassembling."},
247 { LLDB_OPT_SET_ALL, false, "context"      , 'C', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeNumLines,    "Number of context lines of source to show."},
248 { LLDB_OPT_SET_ALL, false, "mixed"        , 'm', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Enable mixed source and assembly display."},
249 { LLDB_OPT_SET_ALL, false, "raw"          , 'r', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Print raw disassembly with no symbol information."},
250 { LLDB_OPT_SET_ALL, false, "plugin"       , 'P', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypePlugin,      "Name of the disassembler plugin you want to use."},
251 { LLDB_OPT_SET_ALL, false, "flavor"       , 'F', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeDisassemblyFlavor,        "Name of the disassembly flavor you want to use.  "
252                                                                                                           "Currently the only valid options are default, and for Intel"
253                                                                                                           " architectures, att and intel."},
254 { LLDB_OPT_SET_ALL, false, "arch"         , 'A', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeArchitecture,"Specify the architecture to use from cross disassembly."},
255 { LLDB_OPT_SET_1  |
256   LLDB_OPT_SET_2  , true , "start-address", 's', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeAddressOrExpression,"Address at which to start disassembling."},
257 { LLDB_OPT_SET_1  , false, "end-address"  , 'e', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeAddressOrExpression,  "Address at which to end disassembling."},
258 { LLDB_OPT_SET_2  |
259   LLDB_OPT_SET_3  |
260   LLDB_OPT_SET_4  |
261   LLDB_OPT_SET_5  , false, "count"        , 'c', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeNumLines,    "Number of instructions to display."},
262 { LLDB_OPT_SET_3  , false, "name"         , 'n', OptionParser::eRequiredArgument  , nullptr, nullptr, CommandCompletions::eSymbolCompletion, eArgTypeFunctionName,
263                                                                                                           "Disassemble entire contents of the given function name."},
264 { LLDB_OPT_SET_4  , false, "frame"        , 'f', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Disassemble from the start of the current frame's function."},
265 { LLDB_OPT_SET_5  , false, "pc"           , 'p', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Disassemble around the current pc."},
266 { LLDB_OPT_SET_6  , false, "line"         , 'l', OptionParser::eNoArgument        , nullptr, nullptr, 0, eArgTypeNone,        "Disassemble the current frame's current source line instructions if there is debug line table information, else disassemble around the pc."},
267 { LLDB_OPT_SET_7  , false, "address"      , 'a', OptionParser::eRequiredArgument  , nullptr, nullptr, 0, eArgTypeAddressOrExpression, "Disassemble function containing this address."},
268 { 0               , false, nullptr           ,   0, 0                  , nullptr, nullptr, 0, eArgTypeNone,        nullptr }
269 };
270 
271 //-------------------------------------------------------------------------
272 // CommandObjectDisassemble
273 //-------------------------------------------------------------------------
274 
275 CommandObjectDisassemble::CommandObjectDisassemble(CommandInterpreter &interpreter)
276     : CommandObjectParsed(interpreter, "disassemble", "Disassemble specified instructions in the current target.  "
277                                                       "Defaults to the current function for the current thread and "
278                                                       "stack frame.",
279                           "disassemble [<cmd-options>]"),
280       m_options()
281 {
282 }
283 
284 CommandObjectDisassemble::~CommandObjectDisassemble() = default;
285 
286 bool
287 CommandObjectDisassemble::DoExecute (Args& command, CommandReturnObject &result)
288 {
289     Target *target = m_interpreter.GetDebugger().GetSelectedTarget().get();
290     if (target == nullptr)
291     {
292         result.AppendError ("invalid target, create a debug target using the 'target create' command");
293         result.SetStatus (eReturnStatusFailed);
294         return false;
295     }
296     if (!m_options.arch.IsValid())
297         m_options.arch = target->GetArchitecture();
298 
299     if (!m_options.arch.IsValid())
300     {
301         result.AppendError ("use the --arch option or set the target architecture to disassemble");
302         result.SetStatus (eReturnStatusFailed);
303         return false;
304     }
305 
306     const char *plugin_name = m_options.GetPluginName ();
307     const char *flavor_string = m_options.GetFlavorString();
308 
309     DisassemblerSP disassembler = Disassembler::FindPlugin(m_options.arch, flavor_string, plugin_name);
310 
311     if (!disassembler)
312     {
313         if (plugin_name)
314         {
315             result.AppendErrorWithFormat ("Unable to find Disassembler plug-in named '%s' that supports the '%s' architecture.\n",
316                                           plugin_name,
317                                           m_options.arch.GetArchitectureName());
318         }
319         else
320             result.AppendErrorWithFormat ("Unable to find Disassembler plug-in for the '%s' architecture.\n",
321                                           m_options.arch.GetArchitectureName());
322         result.SetStatus (eReturnStatusFailed);
323         return false;
324     }
325     else if (flavor_string != nullptr && !disassembler->FlavorValidForArchSpec(m_options.arch, flavor_string))
326         result.AppendWarningWithFormat("invalid disassembler flavor \"%s\", using default.\n", flavor_string);
327 
328     result.SetStatus (eReturnStatusSuccessFinishResult);
329 
330     if (command.GetArgumentCount() != 0)
331     {
332         result.AppendErrorWithFormat ("\"disassemble\" arguments are specified as options.\n");
333         const int terminal_width =
334             GetCommandInterpreter().GetDebugger().GetTerminalWidth();
335         GetOptions()->GenerateOptionUsage(result.GetErrorStream(), this,
336                                           terminal_width);
337         result.SetStatus (eReturnStatusFailed);
338         return false;
339     }
340 
341     if (m_options.show_mixed && m_options.num_lines_context == 0)
342         m_options.num_lines_context = 1;
343 
344     // Always show the PC in the disassembly
345     uint32_t options = Disassembler::eOptionMarkPCAddress;
346 
347     // Mark the source line for the current PC only if we are doing mixed source and assembly
348     if (m_options.show_mixed)
349         options |= Disassembler::eOptionMarkPCSourceLine;
350 
351     if (m_options.show_bytes)
352         options |= Disassembler::eOptionShowBytes;
353 
354     if (m_options.raw)
355         options |= Disassembler::eOptionRawOuput;
356 
357     if (!m_options.func_name.empty())
358     {
359         ConstString name(m_options.func_name.c_str());
360 
361         if (Disassembler::Disassemble(m_interpreter.GetDebugger(),
362                                       m_options.arch,
363                                       plugin_name,
364                                       flavor_string,
365                                       m_exe_ctx,
366                                       name,
367                                       nullptr,    // Module *
368                                       m_options.num_instructions,
369                                       m_options.show_mixed ? m_options.num_lines_context : 0,
370                                       options,
371                                       result.GetOutputStream()))
372         {
373             result.SetStatus (eReturnStatusSuccessFinishResult);
374         }
375         else
376         {
377             result.AppendErrorWithFormat ("Unable to find symbol with name '%s'.\n", name.GetCString());
378             result.SetStatus (eReturnStatusFailed);
379         }
380     }
381     else
382     {
383         std::vector<AddressRange> ranges;
384         AddressRange range;
385         StackFrame *frame = m_exe_ctx.GetFramePtr();
386         if (m_options.frame_line)
387         {
388             if (frame == nullptr)
389             {
390                 result.AppendError ("Cannot disassemble around the current line without a selected frame.\n");
391                 result.SetStatus (eReturnStatusFailed);
392                 return false;
393             }
394             LineEntry pc_line_entry (frame->GetSymbolContext(eSymbolContextLineEntry).line_entry);
395             if (pc_line_entry.IsValid())
396             {
397                 range = pc_line_entry.range;
398             }
399             else
400             {
401                 m_options.at_pc = true; // No line entry, so just disassemble around the current pc
402                 m_options.show_mixed = false;
403             }
404         }
405         else if (m_options.current_function)
406         {
407             if (frame == nullptr)
408             {
409                 result.AppendError ("Cannot disassemble around the current function without a selected frame.\n");
410                 result.SetStatus (eReturnStatusFailed);
411                 return false;
412             }
413             Symbol *symbol = frame->GetSymbolContext(eSymbolContextSymbol).symbol;
414             if (symbol)
415             {
416                 range.GetBaseAddress() = symbol->GetAddress();
417                 range.SetByteSize(symbol->GetByteSize());
418             }
419         }
420 
421         // Did the "m_options.frame_line" find a valid range already? If so
422         // skip the rest...
423         if (range.GetByteSize() == 0)
424         {
425             if (m_options.at_pc)
426             {
427                 if (frame == nullptr)
428                 {
429                     result.AppendError ("Cannot disassemble around the current PC without a selected frame.\n");
430                     result.SetStatus (eReturnStatusFailed);
431                     return false;
432                 }
433                 range.GetBaseAddress() = frame->GetFrameCodeAddress();
434                 if (m_options.num_instructions == 0)
435                 {
436                     // Disassembling at the PC always disassembles some number of instructions (not the whole function).
437                     m_options.num_instructions = DEFAULT_DISASM_NUM_INS;
438                 }
439                 ranges.push_back(range);
440             }
441             else
442             {
443                 range.GetBaseAddress().SetOffset (m_options.start_addr);
444                 if (range.GetBaseAddress().IsValid())
445                 {
446                     if (m_options.end_addr != LLDB_INVALID_ADDRESS)
447                     {
448                         if (m_options.end_addr <= m_options.start_addr)
449                         {
450                             result.AppendErrorWithFormat ("End address before start address.\n");
451                             result.SetStatus (eReturnStatusFailed);
452                             return false;
453                         }
454                         range.SetByteSize (m_options.end_addr - m_options.start_addr);
455                     }
456                     ranges.push_back(range);
457                 }
458                 else
459                 {
460                     if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS
461                         && target)
462                     {
463                         if (!target->GetSectionLoadList().IsEmpty())
464                         {
465                             bool failed = false;
466                             Address symbol_containing_address;
467                             if (target->GetSectionLoadList().ResolveLoadAddress (m_options.symbol_containing_addr, symbol_containing_address))
468                             {
469                                 ModuleSP module_sp (symbol_containing_address.GetModule());
470                                 SymbolContext sc;
471                                 bool resolve_tail_call_address = true; // PC can be one past the address range of the function.
472                                 module_sp->ResolveSymbolContextForAddress (symbol_containing_address, eSymbolContextEverything, sc,
473                                                                            resolve_tail_call_address);
474                                 if (sc.function || sc.symbol)
475                                 {
476                                     sc.GetAddressRange (eSymbolContextFunction | eSymbolContextSymbol, 0, false, range);
477                                 }
478                                 else
479                                 {
480                                     failed = true;
481                                 }
482                             }
483                             else
484                             {
485                                 failed = true;
486                             }
487                             if (failed)
488                             {
489                                 result.AppendErrorWithFormat ("Could not find function bounds for address 0x%" PRIx64 "\n", m_options.symbol_containing_addr);
490                                 result.SetStatus (eReturnStatusFailed);
491                                 return false;
492                             }
493                             ranges.push_back(range);
494                         }
495                         else
496                         {
497                             for (lldb::ModuleSP module_sp : target->GetImages().Modules())
498                             {
499                                 lldb::addr_t file_addr = m_options.symbol_containing_addr;
500                                 Address file_address;
501                                 if (module_sp->ResolveFileAddress(file_addr, file_address))
502                                 {
503                                     SymbolContext sc;
504                                     bool resolve_tail_call_address = true; // PC can be one past the address range of the function.
505                                     module_sp->ResolveSymbolContextForAddress (file_address, eSymbolContextEverything, sc, resolve_tail_call_address);
506                                     if (sc.function || sc.symbol)
507                                     {
508                                         sc.GetAddressRange (eSymbolContextFunction | eSymbolContextSymbol, 0, false, range);
509                                         ranges.push_back(range);
510                                     }
511                                 }
512                             }
513                         }
514                     }
515                 }
516             }
517         }
518         else
519             ranges.push_back(range);
520 
521         if (m_options.num_instructions != 0)
522         {
523             if (ranges.empty())
524             {
525                 // The default action is to disassemble the current frame function.
526                 if (frame)
527                 {
528                     SymbolContext sc(frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextSymbol));
529                     if (sc.function)
530                         range.GetBaseAddress() = sc.function->GetAddressRange().GetBaseAddress();
531                     else if (sc.symbol && sc.symbol->ValueIsAddress())
532                         range.GetBaseAddress() = sc.symbol->GetAddress();
533                     else
534                         range.GetBaseAddress() = frame->GetFrameCodeAddress();
535                 }
536 
537                 if (!range.GetBaseAddress().IsValid())
538                 {
539                     result.AppendError ("invalid frame");
540                     result.SetStatus (eReturnStatusFailed);
541                     return false;
542                 }
543             }
544 
545             bool print_sc_header = ranges.size() > 1;
546             for (AddressRange cur_range : ranges)
547             {
548                 if (Disassembler::Disassemble (m_interpreter.GetDebugger(),
549                                                m_options.arch,
550                                                plugin_name,
551                                                flavor_string,
552                                                m_exe_ctx,
553                                                cur_range.GetBaseAddress(),
554                                                m_options.num_instructions,
555                                                m_options.show_mixed ? m_options.num_lines_context : 0,
556                                                options,
557                                                result.GetOutputStream()))
558                 {
559                     result.SetStatus (eReturnStatusSuccessFinishResult);
560                 }
561                 else
562                 {
563                     if (m_options.start_addr != LLDB_INVALID_ADDRESS)
564                         result.AppendErrorWithFormat ("Failed to disassemble memory at 0x%8.8" PRIx64 ".\n", m_options.start_addr);
565                     else if (m_options.symbol_containing_addr != LLDB_INVALID_ADDRESS)
566                         result.AppendErrorWithFormat ("Failed to disassemble memory in function at 0x%8.8" PRIx64 ".\n", m_options.symbol_containing_addr);
567                     result.SetStatus (eReturnStatusFailed);
568                 }
569             }
570             if (print_sc_header)
571                 result.AppendMessage("\n");
572         }
573         else
574         {
575             if (ranges.empty())
576             {
577                 // The default action is to disassemble the current frame function.
578                 if (frame)
579                 {
580                     SymbolContext sc(frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextSymbol));
581                     if (sc.function)
582                         range = sc.function->GetAddressRange();
583                     else if (sc.symbol && sc.symbol->ValueIsAddress())
584                     {
585                         range.GetBaseAddress() = sc.symbol->GetAddress();
586                         range.SetByteSize (sc.symbol->GetByteSize());
587                     }
588                     else
589                         range.GetBaseAddress() = frame->GetFrameCodeAddress();
590                 }
591                 else
592                 {
593                     result.AppendError ("invalid frame");
594                     result.SetStatus (eReturnStatusFailed);
595                     return false;
596                 }
597                 ranges.push_back(range);
598             }
599 
600             bool print_sc_header = ranges.size() > 1;
601             for (AddressRange cur_range : ranges)
602             {
603                 if (cur_range.GetByteSize() == 0)
604                     cur_range.SetByteSize(DEFAULT_DISASM_BYTE_SIZE);
605 
606                 if (Disassembler::Disassemble (m_interpreter.GetDebugger(),
607                                                m_options.arch,
608                                                plugin_name,
609                                                flavor_string,
610                                                m_exe_ctx,
611                                                cur_range,
612                                                m_options.num_instructions,
613                                                m_options.show_mixed ? m_options.num_lines_context : 0,
614                                                options,
615                                                result.GetOutputStream()))
616                 {
617                     result.SetStatus (eReturnStatusSuccessFinishResult);
618                 }
619                 else
620                 {
621                     result.AppendErrorWithFormat ("Failed to disassemble memory at 0x%8.8" PRIx64 ".\n", m_options.start_addr);
622                     result.SetStatus (eReturnStatusFailed);
623                 }
624                 if (print_sc_header)
625                     result.AppendMessage("\n");
626             }
627         }
628     }
629 
630     return result.Succeeded();
631 }
632