xref: /freebsd/contrib/llvm-project/lldb/source/Target/AssertFrameRecognizer.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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.
GetAbortLocation(llvm::Triple::OSType os,SymbolLocation & location)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.
GetAssertLocation(llvm::Triple::OSType os,SymbolLocation & location)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 
RegisterAssertFrameRecognizer(Process * process)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         /*first_instruction_only*/ false);
93     return;
94   }
95   std::string module_re = "^";
96   for (char c : location.module_spec.GetFilename().GetStringRef()) {
97     if (c == '.')
98       module_re += '\\';
99     module_re += c;
100   }
101   module_re += '$';
102   std::string symbol_re = "^(";
103   for (auto it = location.symbols.cbegin(); it != location.symbols.cend();
104        ++it) {
105     if (it != location.symbols.cbegin())
106       symbol_re += '|';
107     symbol_re += it->GetStringRef();
108   }
109   // Strip the trailing @VER symbol version.
110   symbol_re += ")(@.*)?$";
111   target.GetFrameRecognizerManager().AddRecognizer(
112       std::make_shared<AssertFrameRecognizer>(),
113       std::make_shared<RegularExpression>(std::move(module_re)),
114       std::make_shared<RegularExpression>(std::move(symbol_re)),
115       /*first_instruction_only*/ false);
116 }
117 
118 } // namespace lldb_private
119 
120 lldb::RecognizedStackFrameSP
RecognizeFrame(lldb::StackFrameSP frame_sp)121 AssertFrameRecognizer::RecognizeFrame(lldb::StackFrameSP frame_sp) {
122   ThreadSP thread_sp = frame_sp->GetThread();
123   ProcessSP process_sp = thread_sp->GetProcess();
124   Target &target = process_sp->GetTarget();
125   llvm::Triple::OSType os = target.GetArchitecture().GetTriple().getOS();
126   SymbolLocation location;
127 
128   if (!GetAssertLocation(os, location))
129     return RecognizedStackFrameSP();
130 
131   const uint32_t frames_to_fetch = 6;
132   const uint32_t last_frame_index = frames_to_fetch - 1;
133   StackFrameSP prev_frame_sp = nullptr;
134 
135   // Fetch most relevant frame
136   for (uint32_t frame_index = 0; frame_index < frames_to_fetch; frame_index++) {
137     prev_frame_sp = thread_sp->GetStackFrameAtIndex(frame_index);
138 
139     if (!prev_frame_sp) {
140       Log *log = GetLog(LLDBLog::Unwind);
141       LLDB_LOG(log, "Abort Recognizer: Hit unwinding bound ({1} frames)!",
142                frames_to_fetch);
143       break;
144     }
145 
146     SymbolContext sym_ctx =
147         prev_frame_sp->GetSymbolContext(eSymbolContextEverything);
148 
149     if (!sym_ctx.module_sp ||
150         !sym_ctx.module_sp->GetFileSpec().FileEquals(location.module_spec))
151       continue;
152 
153     ConstString func_name = sym_ctx.GetFunctionName();
154 
155     if (llvm::is_contained(location.symbols, func_name)) {
156       // We go a frame beyond the assert location because the most relevant
157       // frame for the user is the one in which the assert function was called.
158       // If the assert location is the last frame fetched, then it is set as
159       // the most relevant frame.
160 
161       StackFrameSP most_relevant_frame_sp = thread_sp->GetStackFrameAtIndex(
162           std::min(frame_index + 1, last_frame_index));
163 
164       // Pass assert location to AbortRecognizedStackFrame to set as most
165       // relevant frame.
166       return lldb::RecognizedStackFrameSP(
167           new AssertRecognizedStackFrame(most_relevant_frame_sp));
168     }
169   }
170 
171   return RecognizedStackFrameSP();
172 }
173 
AssertRecognizedStackFrame(StackFrameSP most_relevant_frame_sp)174 AssertRecognizedStackFrame::AssertRecognizedStackFrame(
175     StackFrameSP most_relevant_frame_sp)
176     : m_most_relevant_frame(most_relevant_frame_sp) {
177   m_stop_desc = "hit program assert";
178 }
179 
GetMostRelevantFrame()180 lldb::StackFrameSP AssertRecognizedStackFrame::GetMostRelevantFrame() {
181   return m_most_relevant_frame;
182 }
183