contrib/llvm-project/lldb/source/Breakpoint/BreakpointResolver.cpp

   1 //===-- BreakpointResolver.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/Breakpoint/BreakpointResolver.h"
  10
  11 #include "lldb/Breakpoint/Breakpoint.h"
  12 #include "lldb/Breakpoint/BreakpointLocation.h"
  13 // Have to include the other breakpoint resolver types here so the static
  14 // create from StructuredData can call them.
  15 #include "lldb/Breakpoint/BreakpointResolverAddress.h"
  16 #include "lldb/Breakpoint/BreakpointResolverFileLine.h"
  17 #include "lldb/Breakpoint/BreakpointResolverFileRegex.h"
  18 #include "lldb/Breakpoint/BreakpointResolverName.h"
  19 #include "lldb/Breakpoint/BreakpointResolverScripted.h"
  20 #include "lldb/Core/Address.h"
  21 #include "lldb/Core/ModuleList.h"
  22 #include "lldb/Core/SearchFilter.h"
  23 #include "lldb/Symbol/CompileUnit.h"
  24 #include "lldb/Symbol/Function.h"
  25 #include "lldb/Symbol/SymbolContext.h"
  26 #include "lldb/Target/Target.h"
  27 #include "lldb/Utility/Log.h"
  28 #include "lldb/Utility/Stream.h"
  29 #include "lldb/Utility/StreamString.h"
  30
  31 using namespace lldb_private;
  32 using namespace lldb;
  33
  34 // BreakpointResolver:
  35 const char *BreakpointResolver::g_ty_to_name[] = {"FileAndLine", "Address",
  36                                                   "SymbolName",  "SourceRegex",
  37                                                   "Python",   "Exception",
  38                                                   "Unknown"};
  39
  40 const char *BreakpointResolver::g_option_names[static_cast<uint32_t>(
  41     BreakpointResolver::OptionNames::LastOptionName)] = {
  42     "AddressOffset", "Exact",     "FileName",     "Inlines",     "Language",
  43     "LineNumber",    "Column",    "ModuleName",   "NameMask",    "Offset",
  44     "PythonClass",   "Regex",     "ScriptArgs",   "SectionName", "SearchDepth",
  45     "SkipPrologue",  "SymbolNames"};
  46
  47 const char *BreakpointResolver::ResolverTyToName(enum ResolverTy type) {
  48   if (type > LastKnownResolverType)
  49     return g_ty_to_name[UnknownResolver];
  50
  51   return g_ty_to_name[type];
  52 }
  53
  54 BreakpointResolver::ResolverTy
  55 BreakpointResolver::NameToResolverTy(llvm::StringRef name) {
  56   for (size_t i = 0; i < LastKnownResolverType; i++) {
  57     if (name == g_ty_to_name[i])
  58       return (ResolverTy)i;
  59   }
  60   return UnknownResolver;
  61 }
  62
  63 BreakpointResolver::BreakpointResolver(const BreakpointSP &bkpt,
  64                                        const unsigned char resolverTy,
  65                                        lldb::addr_t offset)
  66     : m_breakpoint(bkpt), m_offset(offset), SubclassID(resolverTy) {}
  67
  68 BreakpointResolver::~BreakpointResolver() {}
  69
  70 BreakpointResolverSP BreakpointResolver::CreateFromStructuredData(
  71     const StructuredData::Dictionary &resolver_dict, Status &error) {
  72   BreakpointResolverSP result_sp;
  73   if (!resolver_dict.IsValid()) {
  74     error.SetErrorString("Can't deserialize from an invalid data object.");
  75     return result_sp;
  76   }
  77
  78   llvm::StringRef subclass_name;
  79
  80   bool success = resolver_dict.GetValueForKeyAsString(
  81       GetSerializationSubclassKey(), subclass_name);
  82
  83   if (!success) {
  84     error.SetErrorStringWithFormat(
  85         "Resolver data missing subclass resolver key");
  86     return result_sp;
  87   }
  88
  89   ResolverTy resolver_type = NameToResolverTy(subclass_name);
  90   if (resolver_type == UnknownResolver) {
  91     error.SetErrorStringWithFormatv("Unknown resolver type: {0}.",
  92                                     subclass_name);
  93     return result_sp;
  94   }
  95
  96   StructuredData::Dictionary *subclass_options = nullptr;
  97   success = resolver_dict.GetValueForKeyAsDictionary(
  98       GetSerializationSubclassOptionsKey(), subclass_options);
  99   if (!success || !subclass_options || !subclass_options->IsValid()) {
 100     error.SetErrorString("Resolver data missing subclass options key.");
 101     return result_sp;
 102   }
 103
 104   lldb::addr_t offset;
 105   success = subclass_options->GetValueForKeyAsInteger(
 106       GetKey(OptionNames::Offset), offset);
 107   if (!success) {
 108     error.SetErrorString("Resolver data missing offset options key.");
 109     return result_sp;
 110   }
 111
 112   BreakpointResolver *resolver;
 113
 114   switch (resolver_type) {
 115   case FileLineResolver:
 116     resolver = BreakpointResolverFileLine::CreateFromStructuredData(
 117         nullptr, *subclass_options, error);
 118     break;
 119   case AddressResolver:
 120     resolver = BreakpointResolverAddress::CreateFromStructuredData(
 121         nullptr, *subclass_options, error);
 122     break;
 123   case NameResolver:
 124     resolver = BreakpointResolverName::CreateFromStructuredData(
 125         nullptr, *subclass_options, error);
 126     break;
 127   case FileRegexResolver:
 128     resolver = BreakpointResolverFileRegex::CreateFromStructuredData(
 129         nullptr, *subclass_options, error);
 130     break;
 131   case PythonResolver:
 132     resolver = BreakpointResolverScripted::CreateFromStructuredData(
 133         nullptr, *subclass_options, error);
 134     break;
 135   case ExceptionResolver:
 136     error.SetErrorString("Exception resolvers are hard.");
 137     break;
 138   default:
 139     llvm_unreachable("Should never get an unresolvable resolver type.");
 140   }
 141
 142   if (!error.Success()) {
 143     return result_sp;
 144   } else {
 145     // Add on the global offset option:
 146     resolver->SetOffset(offset);
 147     return BreakpointResolverSP(resolver);
 148   }
 149 }
 150
 151 StructuredData::DictionarySP BreakpointResolver::WrapOptionsDict(
 152     StructuredData::DictionarySP options_dict_sp) {
 153   if (!options_dict_sp || !options_dict_sp->IsValid())
 154     return StructuredData::DictionarySP();
 155
 156   StructuredData::DictionarySP type_dict_sp(new StructuredData::Dictionary());
 157   type_dict_sp->AddStringItem(GetSerializationSubclassKey(), GetResolverName());
 158   type_dict_sp->AddItem(GetSerializationSubclassOptionsKey(), options_dict_sp);
 159
 160   // Add the m_offset to the dictionary:
 161   options_dict_sp->AddIntegerItem(GetKey(OptionNames::Offset), m_offset);
 162
 163   return type_dict_sp;
 164 }
 165
 166 void BreakpointResolver::SetBreakpoint(const BreakpointSP &bkpt) {
 167   assert(bkpt);
 168   m_breakpoint = bkpt;
 169   NotifyBreakpointSet();
 170 }
 171
 172 void BreakpointResolver::ResolveBreakpointInModules(SearchFilter &filter,
 173                                                     ModuleList &modules) {
 174   filter.SearchInModuleList(*this, modules);
 175 }
 176
 177 void BreakpointResolver::ResolveBreakpoint(SearchFilter &filter) {
 178   filter.Search(*this);
 179 }
 180
 181 namespace {
 182 struct SourceLoc {
 183   uint32_t line = UINT32_MAX;
 184   uint32_t column;
 185   SourceLoc(uint32_t l, uint32_t c) : line(l), column(c ? c : UINT32_MAX) {}
 186   SourceLoc(const SymbolContext &sc)
 187       : line(sc.line_entry.line),
 188         column(sc.line_entry.column ? sc.line_entry.column : UINT32_MAX) {}
 189 };
 190
 191 bool operator<(const SourceLoc a, const SourceLoc b) {
 192   if (a.line < b.line)
 193     return true;
 194   if (a.line > b.line)
 195     return false;
 196   uint32_t a_col = a.column ? a.column : UINT32_MAX;
 197   uint32_t b_col = b.column ? b.column : UINT32_MAX;
 198   return a_col < b_col;
 199 }
 200 } // namespace
 201
 202 void BreakpointResolver::SetSCMatchesByLine(SearchFilter &filter,
 203                                             SymbolContextList &sc_list,
 204                                             bool skip_prologue,
 205                                             llvm::StringRef log_ident,
 206                                             uint32_t line, uint32_t column) {
 207   llvm::SmallVector<SymbolContext, 16> all_scs;
 208   for (uint32_t i = 0; i < sc_list.GetSize(); ++i)
 209     all_scs.push_back(sc_list[i]);
 210
 211   while (all_scs.size()) {
 212     uint32_t closest_line = UINT32_MAX;
 213
 214     // Move all the elements with a matching file spec to the end.
 215     auto &match = all_scs[0];
 216     auto worklist_begin = std::partition(
 217         all_scs.begin(), all_scs.end(), [&](const SymbolContext &sc) {
 218           if (sc.line_entry.file == match.line_entry.file ||
 219               sc.line_entry.original_file == match.line_entry.original_file) {
 220             // When a match is found, keep track of the smallest line number.
 221             closest_line = std::min(closest_line, sc.line_entry.line);
 222             return false;
 223           }
 224           return true;
 225         });
 226
 227     // (worklist_begin, worklist_end) now contains all entries for one filespec.
 228     auto worklist_end = all_scs.end();
 229
 230     if (column) {
 231       // If a column was requested, do a more precise match and only
 232       // return the first location that comes after or at the
 233       // requested location.
 234       SourceLoc requested(line, column);
 235       // First, filter out all entries left of the requested column.
 236       worklist_end = std::remove_if(
 237           worklist_begin, worklist_end,
 238           [&](const SymbolContext &sc) { return SourceLoc(sc) < requested; });
 239       // Sort the remaining entries by (line, column).
 240       llvm::sort(worklist_begin, worklist_end,
 241                  [](const SymbolContext &a, const SymbolContext &b) {
 242                    return SourceLoc(a) < SourceLoc(b);
 243                  });
 244
 245       // Filter out all locations with a source location after the closest match.
 246       if (worklist_begin != worklist_end)
 247         worklist_end = std::remove_if(
 248             worklist_begin, worklist_end, [&](const SymbolContext &sc) {
 249               return SourceLoc(*worklist_begin) < SourceLoc(sc);
 250             });
 251     } else {
 252       // Remove all entries with a larger line number.
 253       // ResolveSymbolContext will always return a number that is >=
 254       // the line number you pass in. So the smaller line number is
 255       // always better.
 256       worklist_end = std::remove_if(worklist_begin, worklist_end,
 257                                     [&](const SymbolContext &sc) {
 258                                       return closest_line != sc.line_entry.line;
 259                                     });
 260     }
 261
 262     // Sort by file address.
 263     llvm::sort(worklist_begin, worklist_end,
 264                [](const SymbolContext &a, const SymbolContext &b) {
 265                  return a.line_entry.range.GetBaseAddress().GetFileAddress() <
 266                         b.line_entry.range.GetBaseAddress().GetFileAddress();
 267                });
 268
 269     // Go through and see if there are line table entries that are
 270     // contiguous, and if so keep only the first of the contiguous range.
 271     // We do this by picking the first location in each lexical block.
 272     llvm::SmallDenseSet<Block *, 8> blocks_with_breakpoints;
 273     for (auto first = worklist_begin; first != worklist_end; ++first) {
 274       assert(!blocks_with_breakpoints.count(first->block));
 275       blocks_with_breakpoints.insert(first->block);
 276       worklist_end =
 277           std::remove_if(std::next(first), worklist_end,
 278                          [&](const SymbolContext &sc) {
 279                            return blocks_with_breakpoints.count(sc.block);
 280                          });
 281     }
 282
 283     // Make breakpoints out of the closest line number match.
 284     for (auto &sc : llvm::make_range(worklist_begin, worklist_end))
 285       AddLocation(filter, sc, skip_prologue, log_ident);
 286
 287     // Remove all contexts processed by this iteration.
 288     all_scs.erase(worklist_begin, all_scs.end());
 289   }
 290 }
 291
 292 void BreakpointResolver::AddLocation(SearchFilter &filter,
 293                                      const SymbolContext &sc,
 294                                      bool skip_prologue,
 295                                      llvm::StringRef log_ident) {
 296   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_BREAKPOINTS));
 297   Address line_start = sc.line_entry.range.GetBaseAddress();
 298   if (!line_start.IsValid()) {
 299     LLDB_LOGF(log,
 300               "error: Unable to set breakpoint %s at file address "
 301               "0x%" PRIx64 "\n",
 302               log_ident.str().c_str(), line_start.GetFileAddress());
 303     return;
 304   }
 305
 306   if (!filter.AddressPasses(line_start)) {
 307     LLDB_LOGF(log,
 308               "Breakpoint %s at file address 0x%" PRIx64
 309               " didn't pass the filter.\n",
 310               log_ident.str().c_str(), line_start.GetFileAddress());
 311   }
 312
 313   // If the line number is before the prologue end, move it there...
 314   bool skipped_prologue = false;
 315   if (skip_prologue && sc.function) {
 316     Address prologue_addr(sc.function->GetAddressRange().GetBaseAddress());
 317     if (prologue_addr.IsValid() && (line_start == prologue_addr)) {
 318       const uint32_t prologue_byte_size = sc.function->GetPrologueByteSize();
 319       if (prologue_byte_size) {
 320         prologue_addr.Slide(prologue_byte_size);
 321
 322         if (filter.AddressPasses(prologue_addr)) {
 323           skipped_prologue = true;
 324           line_start = prologue_addr;
 325         }
 326       }
 327     }
 328   }
 329
 330   BreakpointLocationSP bp_loc_sp(AddLocation(line_start));
 331   if (log && bp_loc_sp && !GetBreakpoint()->IsInternal()) {
 332     StreamString s;
 333     bp_loc_sp->GetDescription(&s, lldb::eDescriptionLevelVerbose);
 334     LLDB_LOGF(log, "Added location (skipped prologue: %s): %s \n",
 335               skipped_prologue ? "yes" : "no", s.GetData());
 336   }
 337 }
 338
 339 BreakpointLocationSP BreakpointResolver::AddLocation(Address loc_addr,
 340                                                      bool *new_location) {
 341   loc_addr.Slide(m_offset);
 342   return GetBreakpoint()->AddLocation(loc_addr, new_location);
 343 }
 344
 345 void BreakpointResolver::SetOffset(lldb::addr_t offset) {
 346   // There may already be an offset, so we are actually adjusting location
 347   // addresses by the difference.
 348   // lldb::addr_t slide = offset - m_offset;
 349   // FIXME: We should go fix up all the already set locations for the new
 350   // slide.
 351
 352   m_offset = offset;
 353 }