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/Language.h"
27 #include "lldb/Target/Target.h"
28 #include "lldb/Utility/LLDBLog.h"
29 #include "lldb/Utility/Log.h"
30 #include "lldb/Utility/Stream.h"
31 #include "lldb/Utility/StreamString.h"
32 #include <optional>
33
34 using namespace lldb_private;
35 using namespace lldb;
36
37 // BreakpointResolver:
38 const char *BreakpointResolver::g_ty_to_name[] = {"FileAndLine", "Address",
39 "SymbolName", "SourceRegex",
40 "Python", "Exception",
41 "Unknown"};
42
43 const char *BreakpointResolver::g_option_names[static_cast<uint32_t>(
44 BreakpointResolver::OptionNames::LastOptionName)] = {
45 "AddressOffset", "Exact", "FileName", "Inlines", "Language",
46 "LineNumber", "Column", "ModuleName", "NameMask", "Offset",
47 "PythonClass", "Regex", "ScriptArgs", "SectionName", "SearchDepth",
48 "SkipPrologue", "SymbolNames"};
49
ResolverTyToName(enum ResolverTy type)50 const char *BreakpointResolver::ResolverTyToName(enum ResolverTy type) {
51 if (type > LastKnownResolverType)
52 return g_ty_to_name[UnknownResolver];
53
54 return g_ty_to_name[type];
55 }
56
57 BreakpointResolver::ResolverTy
NameToResolverTy(llvm::StringRef name)58 BreakpointResolver::NameToResolverTy(llvm::StringRef name) {
59 for (size_t i = 0; i < LastKnownResolverType; i++) {
60 if (name == g_ty_to_name[i])
61 return (ResolverTy)i;
62 }
63 return UnknownResolver;
64 }
65
BreakpointResolver(const BreakpointSP & bkpt,const unsigned char resolverTy,lldb::addr_t offset)66 BreakpointResolver::BreakpointResolver(const BreakpointSP &bkpt,
67 const unsigned char resolverTy,
68 lldb::addr_t offset)
69 : m_breakpoint(bkpt), m_offset(offset), SubclassID(resolverTy) {}
70
71 BreakpointResolver::~BreakpointResolver() = default;
72
CreateFromStructuredData(const StructuredData::Dictionary & resolver_dict,Status & error)73 BreakpointResolverSP BreakpointResolver::CreateFromStructuredData(
74 const StructuredData::Dictionary &resolver_dict, Status &error) {
75 BreakpointResolverSP result_sp;
76 if (!resolver_dict.IsValid()) {
77 error.SetErrorString("Can't deserialize from an invalid data object.");
78 return result_sp;
79 }
80
81 llvm::StringRef subclass_name;
82
83 bool success = resolver_dict.GetValueForKeyAsString(
84 GetSerializationSubclassKey(), subclass_name);
85
86 if (!success) {
87 error.SetErrorString("Resolver data missing subclass resolver key");
88 return result_sp;
89 }
90
91 ResolverTy resolver_type = NameToResolverTy(subclass_name);
92 if (resolver_type == UnknownResolver) {
93 error.SetErrorStringWithFormatv("Unknown resolver type: {0}.",
94 subclass_name);
95 return result_sp;
96 }
97
98 StructuredData::Dictionary *subclass_options = nullptr;
99 success = resolver_dict.GetValueForKeyAsDictionary(
100 GetSerializationSubclassOptionsKey(), subclass_options);
101 if (!success || !subclass_options || !subclass_options->IsValid()) {
102 error.SetErrorString("Resolver data missing subclass options key.");
103 return result_sp;
104 }
105
106 lldb::offset_t offset;
107 success = subclass_options->GetValueForKeyAsInteger(
108 GetKey(OptionNames::Offset), offset);
109 if (!success) {
110 error.SetErrorString("Resolver data missing offset options key.");
111 return result_sp;
112 }
113
114 switch (resolver_type) {
115 case FileLineResolver:
116 result_sp = BreakpointResolverFileLine::CreateFromStructuredData(
117 *subclass_options, error);
118 break;
119 case AddressResolver:
120 result_sp = BreakpointResolverAddress::CreateFromStructuredData(
121 *subclass_options, error);
122 break;
123 case NameResolver:
124 result_sp = BreakpointResolverName::CreateFromStructuredData(
125 *subclass_options, error);
126 break;
127 case FileRegexResolver:
128 result_sp = BreakpointResolverFileRegex::CreateFromStructuredData(
129 *subclass_options, error);
130 break;
131 case PythonResolver:
132 result_sp = BreakpointResolverScripted::CreateFromStructuredData(
133 *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.Fail() || !result_sp)
143 return {};
144
145 // Add on the global offset option:
146 result_sp->SetOffset(offset);
147 return result_sp;
148 }
149
WrapOptionsDict(StructuredData::DictionarySP options_dict_sp)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
SetBreakpoint(const BreakpointSP & bkpt)165 void BreakpointResolver::SetBreakpoint(const BreakpointSP &bkpt) {
166 assert(bkpt);
167 m_breakpoint = bkpt;
168 NotifyBreakpointSet();
169 }
170
ResolveBreakpointInModules(SearchFilter & filter,ModuleList & modules)171 void BreakpointResolver::ResolveBreakpointInModules(SearchFilter &filter,
172 ModuleList &modules) {
173 filter.SearchInModuleList(*this, modules);
174 }
175
ResolveBreakpoint(SearchFilter & filter)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;
SourceLoc__anon3914934c0111::SourceLoc184 SourceLoc(uint32_t l, std::optional<uint16_t> c)
185 : line(l), column(c ? *c : LLDB_INVALID_COLUMN_NUMBER) {}
SourceLoc__anon3914934c0111::SourceLoc186 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
operator <(const SourceLoc lhs,const SourceLoc rhs)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
SetSCMatchesByLine(SearchFilter & filter,SymbolContextList & sc_list,bool skip_prologue,llvm::StringRef log_ident,uint32_t line,std::optional<uint16_t> column)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
208 for (const auto &sc : sc_list) {
209 if (Language::GetGlobalLanguageProperties()
210 .GetEnableFilterForLineBreakpoints())
211 if (Language *lang = Language::FindPlugin(sc.GetLanguage());
212 lang && lang->IgnoreForLineBreakpoints(sc))
213 continue;
214 all_scs.push_back(sc);
215 }
216
217 while (all_scs.size()) {
218 uint32_t closest_line = UINT32_MAX;
219
220 // Move all the elements with a matching file spec to the end.
221 auto &match = all_scs[0];
222 auto worklist_begin = std::partition(
223 all_scs.begin(), all_scs.end(), [&](const SymbolContext &sc) {
224 if (sc.line_entry.GetFile() == match.line_entry.GetFile() ||
225 sc.line_entry.original_file_sp->Equal(
226 *match.line_entry.original_file_sp,
227 SupportFile::eEqualFileSpecAndChecksumIfSet)) {
228 // When a match is found, keep track of the smallest line number.
229 closest_line = std::min(closest_line, sc.line_entry.line);
230 return false;
231 }
232 return true;
233 });
234
235 // (worklist_begin, worklist_end) now contains all entries for one filespec.
236 auto worklist_end = all_scs.end();
237
238 if (column) {
239 // If a column was requested, do a more precise match and only
240 // return the first location that comes before or at the
241 // requested location.
242 SourceLoc requested(line, *column);
243 // First, filter out all entries left of the requested column.
244 worklist_end = std::remove_if(
245 worklist_begin, worklist_end,
246 [&](const SymbolContext &sc) { return requested < SourceLoc(sc); });
247 // Sort the remaining entries by (line, column).
248 llvm::sort(worklist_begin, worklist_end,
249 [](const SymbolContext &a, const SymbolContext &b) {
250 return SourceLoc(a) < SourceLoc(b);
251 });
252
253 // Filter out all locations with a source location after the closest match.
254 if (worklist_begin != worklist_end)
255 worklist_end = std::remove_if(
256 worklist_begin, worklist_end, [&](const SymbolContext &sc) {
257 return SourceLoc(*worklist_begin) < SourceLoc(sc);
258 });
259 } else {
260 // Remove all entries with a larger line number.
261 // ResolveSymbolContext will always return a number that is >=
262 // the line number you pass in. So the smaller line number is
263 // always better.
264 worklist_end = std::remove_if(worklist_begin, worklist_end,
265 [&](const SymbolContext &sc) {
266 return closest_line != sc.line_entry.line;
267 });
268 }
269
270 // Sort by file address.
271 llvm::sort(worklist_begin, worklist_end,
272 [](const SymbolContext &a, const SymbolContext &b) {
273 return a.line_entry.range.GetBaseAddress().GetFileAddress() <
274 b.line_entry.range.GetBaseAddress().GetFileAddress();
275 });
276
277 // Go through and see if there are line table entries that are
278 // contiguous, and if so keep only the first of the contiguous range.
279 // We do this by picking the first location in each lexical block.
280 llvm::SmallDenseSet<Block *, 8> blocks_with_breakpoints;
281 for (auto first = worklist_begin; first != worklist_end; ++first) {
282 assert(!blocks_with_breakpoints.count(first->block));
283 blocks_with_breakpoints.insert(first->block);
284 worklist_end =
285 std::remove_if(std::next(first), worklist_end,
286 [&](const SymbolContext &sc) {
287 return blocks_with_breakpoints.count(sc.block);
288 });
289 }
290
291 // Make breakpoints out of the closest line number match.
292 for (auto &sc : llvm::make_range(worklist_begin, worklist_end))
293 AddLocation(filter, sc, skip_prologue, log_ident);
294
295 // Remove all contexts processed by this iteration.
296 all_scs.erase(worklist_begin, all_scs.end());
297 }
298 }
299
AddLocation(SearchFilter & filter,const SymbolContext & sc,bool skip_prologue,llvm::StringRef log_ident)300 void BreakpointResolver::AddLocation(SearchFilter &filter,
301 const SymbolContext &sc,
302 bool skip_prologue,
303 llvm::StringRef log_ident) {
304 Log *log = GetLog(LLDBLog::Breakpoints);
305 Address line_start = sc.line_entry.range.GetBaseAddress();
306 if (!line_start.IsValid()) {
307 LLDB_LOGF(log,
308 "error: Unable to set breakpoint %s at file address "
309 "0x%" PRIx64 "\n",
310 log_ident.str().c_str(), line_start.GetFileAddress());
311 return;
312 }
313
314 if (!filter.AddressPasses(line_start)) {
315 LLDB_LOGF(log,
316 "Breakpoint %s at file address 0x%" PRIx64
317 " didn't pass the filter.\n",
318 log_ident.str().c_str(), line_start.GetFileAddress());
319 }
320
321 // If the line number is before the prologue end, move it there...
322 bool skipped_prologue = false;
323 if (skip_prologue && sc.function) {
324 Address prologue_addr(sc.function->GetAddressRange().GetBaseAddress());
325 if (prologue_addr.IsValid() && (line_start == prologue_addr)) {
326 const uint32_t prologue_byte_size = sc.function->GetPrologueByteSize();
327 if (prologue_byte_size) {
328 prologue_addr.Slide(prologue_byte_size);
329
330 if (filter.AddressPasses(prologue_addr)) {
331 skipped_prologue = true;
332 line_start = prologue_addr;
333 }
334 }
335 }
336 }
337
338 BreakpointLocationSP bp_loc_sp(AddLocation(line_start));
339 if (log && bp_loc_sp && !GetBreakpoint()->IsInternal()) {
340 StreamString s;
341 bp_loc_sp->GetDescription(&s, lldb::eDescriptionLevelVerbose);
342 LLDB_LOGF(log, "Added location (skipped prologue: %s): %s \n",
343 skipped_prologue ? "yes" : "no", s.GetData());
344 }
345 }
346
AddLocation(Address loc_addr,bool * new_location)347 BreakpointLocationSP BreakpointResolver::AddLocation(Address loc_addr,
348 bool *new_location) {
349 loc_addr.Slide(m_offset);
350 return GetBreakpoint()->AddLocation(loc_addr, new_location);
351 }
352
SetOffset(lldb::addr_t offset)353 void BreakpointResolver::SetOffset(lldb::addr_t offset) {
354 // There may already be an offset, so we are actually adjusting location
355 // addresses by the difference.
356 // lldb::addr_t slide = offset - m_offset;
357 // FIXME: We should go fix up all the already set locations for the new
358 // slide.
359
360 m_offset = offset;
361 }
362