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/LLDBLog.h"
  28 #include "lldb/Utility/Log.h"
  29 #include "lldb/Utility/Stream.h"
  30 #include "lldb/Utility/StreamString.h"
  31 #include <optional>
  32
  33 using namespace lldb_private;
  34 using namespace lldb;
  35
  36 // BreakpointResolver:
  37 const char *BreakpointResolver::g_ty_to_name[] = {"FileAndLine", "Address",
  38                                                   "SymbolName",  "SourceRegex",
  39                                                   "Python",   "Exception",
  40                                                   "Unknown"};
  41
  42 const char *BreakpointResolver::g_option_names[static_cast<uint32_t>(
  43     BreakpointResolver::OptionNames::LastOptionName)] = {
  44     "AddressOffset", "Exact",     "FileName",     "Inlines",     "Language",
  45     "LineNumber",    "Column",    "ModuleName",   "NameMask",    "Offset",
  46     "PythonClass",   "Regex",     "ScriptArgs",   "SectionName", "SearchDepth",
  47     "SkipPrologue",  "SymbolNames"};
  48
  49 const char *BreakpointResolver::ResolverTyToName(enum ResolverTy type) {
  50   if (type > LastKnownResolverType)
  51     return g_ty_to_name[UnknownResolver];
  52
  53   return g_ty_to_name[type];
  54 }
  55
  56 BreakpointResolver::ResolverTy
  57 BreakpointResolver::NameToResolverTy(llvm::StringRef name) {
  58   for (size_t i = 0; i < LastKnownResolverType; i++) {
  59     if (name == g_ty_to_name[i])
  60       return (ResolverTy)i;
  61   }
  62   return UnknownResolver;
  63 }
  64
  65 BreakpointResolver::BreakpointResolver(const BreakpointSP &bkpt,
  66                                        const unsigned char resolverTy,
  67                                        lldb::addr_t offset)
  68     : m_breakpoint(bkpt), m_offset(offset), SubclassID(resolverTy) {}
  69
  70 BreakpointResolver::~BreakpointResolver() = default;
  71
  72 BreakpointResolverSP BreakpointResolver::CreateFromStructuredData(
  73     const StructuredData::Dictionary &resolver_dict, Status &error) {
  74   BreakpointResolverSP result_sp;
  75   if (!resolver_dict.IsValid()) {
  76     error.SetErrorString("Can't deserialize from an invalid data object.");
  77     return result_sp;
  78   }
  79
  80   llvm::StringRef subclass_name;
  81
  82   bool success = resolver_dict.GetValueForKeyAsString(
  83       GetSerializationSubclassKey(), subclass_name);
  84
  85   if (!success) {
  86     error.SetErrorString("Resolver data missing subclass resolver key");
  87     return result_sp;
  88   }
  89
  90   ResolverTy resolver_type = NameToResolverTy(subclass_name);
  91   if (resolver_type == UnknownResolver) {
  92     error.SetErrorStringWithFormatv("Unknown resolver type: {0}.",
  93                                     subclass_name);
  94     return result_sp;
  95   }
  96
  97   StructuredData::Dictionary *subclass_options = nullptr;
  98   success = resolver_dict.GetValueForKeyAsDictionary(
  99       GetSerializationSubclassOptionsKey(), subclass_options);
 100   if (!success || !subclass_options || !subclass_options->IsValid()) {
 101     error.SetErrorString("Resolver data missing subclass options key.");
 102     return result_sp;
 103   }
 104
 105   lldb::offset_t offset;
 106   success = subclass_options->GetValueForKeyAsInteger(
 107       GetKey(OptionNames::Offset), offset);
 108   if (!success) {
 109     error.SetErrorString("Resolver data missing offset options key.");
 110     return result_sp;
 111   }
 112
 113   BreakpointResolver *resolver = nullptr;
 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 (!resolver || error.Fail())
 143     return result_sp;
 144
 145   // Add on the global offset option:
 146   resolver->SetOffset(offset);
 147   return BreakpointResolverSP(resolver);
 148 }
 149
 150 StructuredData::DictionarySP BreakpointResolver::WrapOptionsDict(
 151     StructuredData::DictionarySP options_dict_sp) {
 152   if (!options_dict_sp || !options_dict_sp->IsValid())
 153     return StructuredData::DictionarySP();
 154
 155   StructuredData::DictionarySP type_dict_sp(new StructuredData::Dictionary());
 156   type_dict_sp->AddStringItem(GetSerializationSubclassKey(), GetResolverName());
 157   type_dict_sp->AddItem(GetSerializationSubclassOptionsKey(), options_dict_sp);
 158
 159   // Add the m_offset to the dictionary:
 160   options_dict_sp->AddIntegerItem(GetKey(OptionNames::Offset), m_offset);
 161
 162   return type_dict_sp;
 163 }
 164
 165 void BreakpointResolver::SetBreakpoint(const BreakpointSP &bkpt) {
 166   assert(bkpt);
 167   m_breakpoint = bkpt;
 168   NotifyBreakpointSet();
 169 }
 170
 171 void BreakpointResolver::ResolveBreakpointInModules(SearchFilter &filter,
 172                                                     ModuleList &modules) {
 173   filter.SearchInModuleList(*this, modules);
 174 }
 175
 176 void BreakpointResolver::ResolveBreakpoint(SearchFilter &filter) {
 177   filter.Search(*this);
 178 }
 179
 180 namespace {
 181 struct SourceLoc {
 182   uint32_t line = UINT32_MAX;
 183   uint16_t column;
 184   SourceLoc(uint32_t l, std::optional<uint16_t> c)
 185       : line(l), column(c ? *c : LLDB_INVALID_COLUMN_NUMBER) {}
 186   SourceLoc(const SymbolContext &sc)
 187       : line(sc.line_entry.line),
 188         column(sc.line_entry.column ? sc.line_entry.column
 189                                     : LLDB_INVALID_COLUMN_NUMBER) {}
 190 };
 191
 192 bool operator<(const SourceLoc lhs, const SourceLoc rhs) {
 193   if (lhs.line < rhs.line)
 194     return true;
 195   if (lhs.line > rhs.line)
 196     return false;
 197   //  uint32_t a_col = lhs.column ? lhs.column : LLDB_INVALID_COLUMN_NUMBER;
 198   //  uint32_t b_col = rhs.column ? rhs.column : LLDB_INVALID_COLUMN_NUMBER;
 199   return lhs.column < rhs.column;
 200 }
 201 } // namespace
 202
 203 void BreakpointResolver::SetSCMatchesByLine(
 204     SearchFilter &filter, SymbolContextList &sc_list, bool skip_prologue,
 205     llvm::StringRef log_ident, uint32_t line, std::optional<uint16_t> column) {
 206   llvm::SmallVector<SymbolContext, 16> all_scs;
 207   for (uint32_t i = 0; i < sc_list.GetSize(); ++i)
 208     all_scs.push_back(sc_list[i]);
 209
 210   while (all_scs.size()) {
 211     uint32_t closest_line = UINT32_MAX;
 212
 213     // Move all the elements with a matching file spec to the end.
 214     auto &match = all_scs[0];
 215     auto worklist_begin = std::partition(
 216         all_scs.begin(), all_scs.end(), [&](const SymbolContext &sc) {
 217           if (sc.line_entry.file == match.line_entry.file ||
 218               sc.line_entry.original_file == match.line_entry.original_file) {
 219             // When a match is found, keep track of the smallest line number.
 220             closest_line = std::min(closest_line, sc.line_entry.line);
 221             return false;
 222           }
 223           return true;
 224         });
 225
 226     // (worklist_begin, worklist_end) now contains all entries for one filespec.
 227     auto worklist_end = all_scs.end();
 228
 229     if (column) {
 230       // If a column was requested, do a more precise match and only
 231       // return the first location that comes before or at the
 232       // requested location.
 233       SourceLoc requested(line, *column);
 234       // First, filter out all entries left of the requested column.
 235       worklist_end = std::remove_if(
 236           worklist_begin, worklist_end,
 237           [&](const SymbolContext &sc) { return requested < SourceLoc(sc); });
 238       // Sort the remaining entries by (line, column).
 239       llvm::sort(worklist_begin, worklist_end,
 240                  [](const SymbolContext &a, const SymbolContext &b) {
 241                    return SourceLoc(a) < SourceLoc(b);
 242                  });
 243
 244       // Filter out all locations with a source location after the closest match.
 245       if (worklist_begin != worklist_end)
 246         worklist_end = std::remove_if(
 247             worklist_begin, worklist_end, [&](const SymbolContext &sc) {
 248               return SourceLoc(*worklist_begin) < SourceLoc(sc);
 249             });
 250     } else {
 251       // Remove all entries with a larger line number.
 252       // ResolveSymbolContext will always return a number that is >=
 253       // the line number you pass in. So the smaller line number is
 254       // always better.
 255       worklist_end = std::remove_if(worklist_begin, worklist_end,
 256                                     [&](const SymbolContext &sc) {
 257                                       return closest_line != sc.line_entry.line;
 258                                     });
 259     }
 260
 261     // Sort by file address.
 262     llvm::sort(worklist_begin, worklist_end,
 263                [](const SymbolContext &a, const SymbolContext &b) {
 264                  return a.line_entry.range.GetBaseAddress().GetFileAddress() <
 265                         b.line_entry.range.GetBaseAddress().GetFileAddress();
 266                });
 267
 268     // Go through and see if there are line table entries that are
 269     // contiguous, and if so keep only the first of the contiguous range.
 270     // We do this by picking the first location in each lexical block.
 271     llvm::SmallDenseSet<Block *, 8> blocks_with_breakpoints;
 272     for (auto first = worklist_begin; first != worklist_end; ++first) {
 273       assert(!blocks_with_breakpoints.count(first->block));
 274       blocks_with_breakpoints.insert(first->block);
 275       worklist_end =
 276           std::remove_if(std::next(first), worklist_end,
 277                          [&](const SymbolContext &sc) {
 278                            return blocks_with_breakpoints.count(sc.block);
 279                          });
 280     }
 281
 282     // Make breakpoints out of the closest line number match.
 283     for (auto &sc : llvm::make_range(worklist_begin, worklist_end))
 284       AddLocation(filter, sc, skip_prologue, log_ident);
 285
 286     // Remove all contexts processed by this iteration.
 287     all_scs.erase(worklist_begin, all_scs.end());
 288   }
 289 }
 290
 291 void BreakpointResolver::AddLocation(SearchFilter &filter,
 292                                      const SymbolContext &sc,
 293                                      bool skip_prologue,
 294                                      llvm::StringRef log_ident) {
 295   Log *log = GetLog(LLDBLog::Breakpoints);
 296   Address line_start = sc.line_entry.range.GetBaseAddress();
 297   if (!line_start.IsValid()) {
 298     LLDB_LOGF(log,
 299               "error: Unable to set breakpoint %s at file address "
 300               "0x%" PRIx64 "\n",
 301               log_ident.str().c_str(), line_start.GetFileAddress());
 302     return;
 303   }
 304
 305   if (!filter.AddressPasses(line_start)) {
 306     LLDB_LOGF(log,
 307               "Breakpoint %s at file address 0x%" PRIx64
 308               " didn't pass the filter.\n",
 309               log_ident.str().c_str(), line_start.GetFileAddress());
 310   }
 311
 312   // If the line number is before the prologue end, move it there...
 313   bool skipped_prologue = false;
 314   if (skip_prologue && sc.function) {
 315     Address prologue_addr(sc.function->GetAddressRange().GetBaseAddress());
 316     if (prologue_addr.IsValid() && (line_start == prologue_addr)) {
 317       const uint32_t prologue_byte_size = sc.function->GetPrologueByteSize();
 318       if (prologue_byte_size) {
 319         prologue_addr.Slide(prologue_byte_size);
 320
 321         if (filter.AddressPasses(prologue_addr)) {
 322           skipped_prologue = true;
 323           line_start = prologue_addr;
 324         }
 325       }
 326     }
 327   }
 328
 329   BreakpointLocationSP bp_loc_sp(AddLocation(line_start));
 330   if (log && bp_loc_sp && !GetBreakpoint()->IsInternal()) {
 331     StreamString s;
 332     bp_loc_sp->GetDescription(&s, lldb::eDescriptionLevelVerbose);
 333     LLDB_LOGF(log, "Added location (skipped prologue: %s): %s \n",
 334               skipped_prologue ? "yes" : "no", s.GetData());
 335   }
 336 }
 337
 338 BreakpointLocationSP BreakpointResolver::AddLocation(Address loc_addr,
 339                                                      bool *new_location) {
 340   loc_addr.Slide(m_offset);
 341   return GetBreakpoint()->AddLocation(loc_addr, new_location);
 342 }
 343
 344 void BreakpointResolver::SetOffset(lldb::addr_t offset) {
 345   // There may already be an offset, so we are actually adjusting location
 346   // addresses by the difference.
 347   // lldb::addr_t slide = offset - m_offset;
 348   // FIXME: We should go fix up all the already set locations for the new
 349   // slide.
 350
 351   m_offset = offset;
 352 }