xref: /llvm-project/lldb/source/Target/AssertFrameRecognizer.cpp (revision dd060bdede8edec18ad5ca122e15cc24a821e3fe)
1 #include "lldb/Target/AssertFrameRecognizer.h"
2 #include "lldb/Core/Module.h"
3 #include "lldb/Symbol/Function.h"
4 #include "lldb/Symbol/SymbolContext.h"
5 #include "lldb/Symbol/SymbolLocation.h"
6 #include "lldb/Target/Process.h"
7 #include "lldb/Target/StackFrameList.h"
8 #include "lldb/Target/Target.h"
9 #include "lldb/Target/Thread.h"
10 #include "lldb/Utility/LLDBLog.h"
11 
12 using namespace llvm;
13 using namespace lldb;
14 using namespace lldb_private;
15 
16 namespace lldb_private {
17 /// Fetches the abort frame location depending on the current platform.
18 ///
19 /// \param[in] os
20 ///    The target's os type.
21 /// \param[in,out] location
22 ///    The struct that will contain the abort module spec and symbol names.
23 /// \return
24 ///    \b true, if the platform is supported
25 ///    \b false, otherwise.
26 bool GetAbortLocation(llvm::Triple::OSType os, SymbolLocation &location) {
27   switch (os) {
28   case llvm::Triple::Darwin:
29   case llvm::Triple::MacOSX:
30     location.module_spec = FileSpec("libsystem_kernel.dylib");
31     location.symbols.push_back(ConstString("__pthread_kill"));
32     break;
33   case llvm::Triple::Linux:
34     location.module_spec = FileSpec("libc.so.6");
35     location.symbols.push_back(ConstString("raise"));
36     location.symbols.push_back(ConstString("__GI_raise"));
37     location.symbols.push_back(ConstString("gsignal"));
38     location.symbols.push_back(ConstString("pthread_kill"));
39     location.symbols_are_regex = true;
40     break;
41   default:
42     Log *log = GetLog(LLDBLog::Unwind);
43     LLDB_LOG(log, "AssertFrameRecognizer::GetAbortLocation Unsupported OS");
44     return false;
45   }
46 
47   return true;
48 }
49 
50 /// Fetches the assert frame location depending on the current platform.
51 ///
52 /// \param[in] os
53 ///    The target's os type.
54 /// \param[in,out] location
55 ///    The struct that will contain the assert module spec and symbol names.
56 /// \return
57 ///    \b true, if the platform is supported
58 ///    \b false, otherwise.
59 bool GetAssertLocation(llvm::Triple::OSType os, SymbolLocation &location) {
60   switch (os) {
61   case llvm::Triple::Darwin:
62   case llvm::Triple::MacOSX:
63     location.module_spec = FileSpec("libsystem_c.dylib");
64     location.symbols.push_back(ConstString("__assert_rtn"));
65     break;
66   case llvm::Triple::Linux:
67     location.module_spec = FileSpec("libc.so.6");
68     location.symbols.push_back(ConstString("__assert_fail"));
69     location.symbols.push_back(ConstString("__GI___assert_fail"));
70     break;
71   default:
72     Log *log = GetLog(LLDBLog::Unwind);
73     LLDB_LOG(log, "AssertFrameRecognizer::GetAssertLocation Unsupported OS");
74     return false;
75   }
76 
77   return true;
78 }
79 
80 void RegisterAssertFrameRecognizer(Process *process) {
81   Target &target = process->GetTarget();
82   llvm::Triple::OSType os = target.GetArchitecture().GetTriple().getOS();
83   SymbolLocation location;
84 
85   if (!GetAbortLocation(os, location))
86     return;
87 
88   if (!location.symbols_are_regex) {
89     target.GetFrameRecognizerManager().AddRecognizer(
90         std::make_shared<AssertFrameRecognizer>(),
91         location.module_spec.GetFilename(), location.symbols,
92         Mangled::ePreferDemangled,
93         /*first_instruction_only*/ false);
94     return;
95   }
96   std::string module_re = "^";
97   for (char c : location.module_spec.GetFilename().GetStringRef()) {
98     if (c == '.')
99       module_re += '\\';
100     module_re += c;
101   }
102   module_re += '$';
103   std::string symbol_re = "^(";
104   for (auto it = location.symbols.cbegin(); it != location.symbols.cend();
105        ++it) {
106     if (it != location.symbols.cbegin())
107       symbol_re += '|';
108     symbol_re += it->GetStringRef();
109   }
110   // Strip the trailing @VER symbol version.
111   symbol_re += ")(@.*)?$";
112   target.GetFrameRecognizerManager().AddRecognizer(
113       std::make_shared<AssertFrameRecognizer>(),
114       std::make_shared<RegularExpression>(std::move(module_re)),
115       std::make_shared<RegularExpression>(std::move(symbol_re)),
116       Mangled::ePreferDemangled,
117       /*first_instruction_only*/ false);
118 }
119 
120 } // namespace lldb_private
121 
122 lldb::RecognizedStackFrameSP
123 AssertFrameRecognizer::RecognizeFrame(lldb::StackFrameSP frame_sp) {
124   ThreadSP thread_sp = frame_sp->GetThread();
125   ProcessSP process_sp = thread_sp->GetProcess();
126   Target &target = process_sp->GetTarget();
127   llvm::Triple::OSType os = target.GetArchitecture().GetTriple().getOS();
128   SymbolLocation location;
129 
130   if (!GetAssertLocation(os, location))
131     return RecognizedStackFrameSP();
132 
133   const uint32_t frames_to_fetch = 6;
134   const uint32_t last_frame_index = frames_to_fetch - 1;
135   StackFrameSP prev_frame_sp = nullptr;
136 
137   // Fetch most relevant frame
138   for (uint32_t frame_index = 0; frame_index < frames_to_fetch; frame_index++) {
139     prev_frame_sp = thread_sp->GetStackFrameAtIndex(frame_index);
140 
141     if (!prev_frame_sp) {
142       Log *log = GetLog(LLDBLog::Unwind);
143       LLDB_LOG(log, "Abort Recognizer: Hit unwinding bound ({1} frames)!",
144                frames_to_fetch);
145       break;
146     }
147 
148     SymbolContext sym_ctx =
149         prev_frame_sp->GetSymbolContext(eSymbolContextEverything);
150 
151     if (!sym_ctx.module_sp ||
152         !sym_ctx.module_sp->GetFileSpec().FileEquals(location.module_spec))
153       continue;
154 
155     ConstString func_name = sym_ctx.GetFunctionName();
156 
157     if (llvm::is_contained(location.symbols, func_name)) {
158       // We go a frame beyond the assert location because the most relevant
159       // frame for the user is the one in which the assert function was called.
160       // If the assert location is the last frame fetched, then it is set as
161       // the most relevant frame.
162 
163       StackFrameSP most_relevant_frame_sp = thread_sp->GetStackFrameAtIndex(
164           std::min(frame_index + 1, last_frame_index));
165 
166       // Pass assert location to AbortRecognizedStackFrame to set as most
167       // relevant frame.
168       return lldb::RecognizedStackFrameSP(
169           new AssertRecognizedStackFrame(most_relevant_frame_sp));
170     }
171   }
172 
173   return RecognizedStackFrameSP();
174 }
175 
176 AssertRecognizedStackFrame::AssertRecognizedStackFrame(
177     StackFrameSP most_relevant_frame_sp)
178     : m_most_relevant_frame(most_relevant_frame_sp) {
179   m_stop_desc = "hit program assert";
180 }
181 
182 lldb::StackFrameSP AssertRecognizedStackFrame::GetMostRelevantFrame() {
183   return m_most_relevant_frame;
184 }
185