Add a verbose mode to "image dump line-table" and use it to write a .debug_line test

[labath]

Summary

The motivation for this is being able to write tests for the upcoming
breakpad line table parser, but this could be useful for testing the
low-level workings of any line table format. Or simply for viewing the
line table information with more detail (the brief format doesn't
include any of the flags for end_of_prologue and similar).

I've also removed the load_addresses argument from the
DumpCompileUnitLineTable function, as it wasn't being used anywhere.

[zturner]

Ok, that makes sense. BTW, it would be nice if someone ever decided to make llvm-mc recognize more symbolic constants so we didn't have to use magic numbers everywhere.

lit/SymbolFile/DWARF/debug-line-basic.s

+# REQUIRES: lld
+
+# RUN: llvm-mc -triple x86_64-pc-linux %s -filetype=obj > %t.o
+# RUN: ld.lld %t.o -o %t
+# RUN: %lldb %t -o "image dump line-table -v a.c" -o exit | FileCheck %s
+
+
+  .text
+  .globl  _start
+_start:
+# CHECK: Line table for /tmp/a.c
+  .file 1 "/tmp/b.c"
+  .loc  1 0 0
+        nop
+# CHECK-NEXT: 0x0000000000201000: /tmp/b.c, is_start_of_statement = TRUE{{$}}
+  .loc  1 1 0
+        nop
+# CHECK-NEXT: 0x0000000000201001: /tmp/b.c:1, is_start_of_statement = TRUE{{$}}
+        .loc   1 1 1
+        nop
+# CHECK-NEXT: 0x0000000000201002: /tmp/b.c:1:1, is_start_of_statement = TRUE{{$}}
+        .loc   1 2 0 is_stmt 0
+        nop
+# CHECK-NEXT: 0x0000000000201003: /tmp/b.c:2{{$}}
+        .loc   1 2 0 is_stmt 0 basic_block
+        nop
+# CHECK-NEXT: 0x0000000000201004: /tmp/b.c:2, is_start_of_basic_block = TRUE{{$}}
+        .loc   1 2 0 is_stmt 0 prologue_end
+        nop
+# CHECK-NEXT: 0x0000000000201005: /tmp/b.c:2, is_prologue_end = TRUE{{$}}
+        .loc   1 2 0 is_stmt 0 epilogue_begin
+        nop
+# CHECK-NEXT: 0x0000000000201006: /tmp/b.c:2, is_epilogue_begin = TRUE{{$}}
+  .file  2 "/tmp/c.c"
+  .loc   2 1 0 is_stmt 0
+        nop
+# CHECK-NEXT: 0x0000000000201007: /tmp/c.c:1{{$}}
+
+# CHECK-NEXT: 0x0000000000201008: /tmp/c.c:1, is_terminal_entry = TRUE{{$}}
+
+  .section  .debug_str,"MS",@progbits,1
+.Linfo_string1:
+  .asciz  "a.c"
+.Linfo_string2:
+  .asciz  "/tmp"
+  .section  .debug_abbrev,"",@progbits
+  .byte 1                       # Abbreviation Code
+  .byte 17                      # DW_TAG_compile_unit
+  .byte 0                       # DW_CHILDREN_no
+  .byte 19                      # DW_AT_language
+  .byte 5                       # DW_FORM_data2
+  .byte 3                       # DW_AT_name
+  .byte 14                      # DW_FORM_strp
+  .byte 16                      # DW_AT_stmt_list
+  .byte 23                      # DW_FORM_sec_offset
+  .byte 27                      # DW_AT_comp_dir
+  .byte 14                      # DW_FORM_strp
+  .byte 0                       # EOM(1)
+  .byte 0                       # EOM(2)
+  .byte 0                       # EOM(3)
+  .section  .debug_info,"",@progbits
+.Lcu_begin0:
+  .long .Lcu_end0-.Lcu_start0   # Length of Unit
+.Lcu_start0:
+  .short  4                       # DWARF version number
+  .long .debug_abbrev           # Offset Into Abbrev. Section
+  .byte 8                       # Address Size (in bytes)
+  .byte 1                       # Abbrev [1] 0xb:0x1f DW_TAG_compile_unit
+  .short  12                      # DW_AT_language
+  .long .Linfo_string1          # DW_AT_name
+  .long .Lline_table_start0     # DW_AT_stmt_list
+  .long .Linfo_string2          # DW_AT_comp_dir
+.Lcu_end0:
+  .section  .debug_line,"",@progbits
+.Lline_table_start0:

source/Commands/CommandObjectTarget.cpp

if (module && module->GetUUID().IsValid())
     module->GetUUID().Dump(&strm);
   else
     strm.PutCString("                                    ");
 }
 
 static uint32_t DumpCompileUnitLineTable(CommandInterpreter &interpreter,
                                          Stream &strm, Module *module,
                                          const FileSpec &file_spec,
-                                         bool load_addresses) {
+                                         lldb::DescriptionLevel desc_level) {
   uint32_t num_matches = 0;
   if (module) {
     SymbolContextList sc_list;
     num_matches = module->ResolveSymbolContextsForFileSpec(
         file_spec, 0, false, eSymbolContextCompUnit, sc_list);
 
     for (uint32_t i = 0; i < num_matches; ++i) {
       SymbolContext sc;
       if (sc_list.GetContextAtIndex(i, sc)) {
         if (i > 0)
           strm << "\n\n";
 
         strm << "Line table for " << *static_cast<FileSpec *>(sc.comp_unit)
              << " in `" << module->GetFileSpec().GetFilename() << "\n";
         LineTable *line_table = sc.comp_unit->GetLineTable();
         if (line_table)
           line_table->GetDescription(
               &strm, interpreter.GetExecutionContext().GetTargetPtr(),
-              lldb::eDescriptionLevelBrief);
+              desc_level);
         else
           strm << "No line table";
       }
     }
   }
   return num_matches;
 }
 
public:
   CommandObjectTargetModulesDumpLineTable(CommandInterpreter &interpreter)
       : CommandObjectTargetModulesSourceFileAutoComplete(
             interpreter, "target modules dump line-table",
             "Dump the line table for one or more compilation units.", nullptr,
             eCommandRequiresTarget) {}
 
   ~CommandObjectTargetModulesDumpLineTable() override = default;
 
+  Options *GetOptions() override { return &m_options; }
+
 protected:
   bool DoExecute(Args &command, CommandReturnObject &result) override {
     Target *target = m_exe_ctx.GetTargetPtr();
     uint32_t total_num_dumped = 0;
 
     uint32_t addr_byte_size = target->GetArchitecture().GetAddressByteSize();
     result.GetOutputStream().SetAddressByteSize(addr_byte_size);
     result.GetErrorStream().SetAddressByteSize(addr_byte_size);
if (command.GetArgumentCount() == 0) {
         if (num_modules > 0) {
           uint32_t num_dumped = 0;
           for (uint32_t i = 0; i < num_modules; ++i) {
             if (m_interpreter.WasInterrupted())
               break;
             if (DumpCompileUnitLineTable(
                     m_interpreter, result.GetOutputStream(),
                     target_modules.GetModulePointerAtIndexUnlocked(i),
-                    file_spec, m_exe_ctx.GetProcessPtr() &&
-                                   m_exe_ctx.GetProcessRef().IsAlive()))
+                    file_spec,
+                    m_options.m_verbose ? eDescriptionLevelFull
+                                        : eDescriptionLevelBrief))
               num_dumped++;
           }
           if (num_dumped == 0)
             result.AppendWarningWithFormat(
                 "No source filenames matched '%s'.\n", arg_cstr);
           else
             total_num_dumped += num_dumped;
         }
       }
     }
 
     if (total_num_dumped > 0)
       result.SetStatus(eReturnStatusSuccessFinishResult);
     else {
       result.AppendError("no source filenames matched any command arguments");
       result.SetStatus(eReturnStatusFailed);
     }
     return result.Succeeded();
   }
+
+  class CommandOptions : public Options {
+  public:
+    CommandOptions() : Options() { OptionParsingStarting(nullptr); }
+
+    Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
+                          ExecutionContext *execution_context) override {
+      assert(option_idx == 0 && "We only have one option.");
+      m_verbose = true;
+
+      return Status();
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_verbose = false;
+    }
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      static constexpr OptionDefinition g_options[] = {
+          {LLDB_OPT_SET_ALL,
+           false,
+           "verbose",
+           'v',
+           OptionParser::eNoArgument,
+           nullptr,
+           {},
+           0,
+           eArgTypeNone,
+           "Enable verbose dump."},
+      };
+      return llvm::makeArrayRef(g_options);
+    }
+
+    bool m_verbose;
+  };
+
+  CommandOptions m_options;
 };
 
 #pragma mark CommandObjectTargetModulesDump
 
 //----------------------------------------------------------------------
 // Dump multi-word command for target modules
 //----------------------------------------------------------------------