1 //===-- IntelJITEventListener.cpp - Tell Intel profiler about JITed code --===//
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 // This file defines a JITEventListener object to tell Intel(R) VTune(TM)
10 // Amplifier XE 2011 about JITted functions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "IntelJITEventsWrapper.h"
15 #include "llvm-c/ExecutionEngine.h"
16 #include "llvm/ADT/DenseMap.h"
17 #include "llvm/CodeGen/MachineFunction.h"
18 #include "llvm/Config/config.h"
19 #include "llvm/DebugInfo/DIContext.h"
20 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
21 #include "llvm/ExecutionEngine/JITEventListener.h"
22 #include "llvm/IR/DebugInfo.h"
23 #include "llvm/IR/Function.h"
24 #include "llvm/IR/Metadata.h"
25 #include "llvm/IR/ValueHandle.h"
26 #include "llvm/Object/ObjectFile.h"
27 #include "llvm/Object/SymbolSize.h"
28 #include "llvm/Support/Debug.h"
29 #include "llvm/Support/Errno.h"
30 #include "llvm/Support/raw_ostream.h"
31 
32 using namespace llvm;
33 using namespace llvm::object;
34 
35 #define DEBUG_TYPE "amplifier-jit-event-listener"
36 
37 namespace {
38 
39 class IntelJITEventListener : public JITEventListener {
40   typedef DenseMap<void*, unsigned int> MethodIDMap;
41 
42   std::unique_ptr<IntelJITEventsWrapper> Wrapper;
43   MethodIDMap MethodIDs;
44 
45   typedef SmallVector<const void *, 64> MethodAddressVector;
46   typedef DenseMap<const void *, MethodAddressVector>  ObjectMap;
47 
48   ObjectMap  LoadedObjectMap;
49   std::map<ObjectKey, OwningBinary<ObjectFile>> DebugObjects;
50 
51 public:
52   IntelJITEventListener(IntelJITEventsWrapper* libraryWrapper) {
53       Wrapper.reset(libraryWrapper);
54   }
55 
56   ~IntelJITEventListener() {
57   }
58 
59   void notifyObjectLoaded(ObjectKey Key, const ObjectFile &Obj,
60                           const RuntimeDyld::LoadedObjectInfo &L) override;
61 
62   void notifyFreeingObject(ObjectKey Key) override;
63 };
64 
65 static LineNumberInfo DILineInfoToIntelJITFormat(uintptr_t StartAddress,
66                                                  uintptr_t Address,
67                                                  DILineInfo Line) {
68   LineNumberInfo Result;
69 
70   Result.Offset = Address - StartAddress;
71   Result.LineNumber = Line.Line;
72 
73   return Result;
74 }
75 
76 static iJIT_Method_Load FunctionDescToIntelJITFormat(
77     IntelJITEventsWrapper& Wrapper,
78     const char* FnName,
79     uintptr_t FnStart,
80     size_t FnSize) {
81   iJIT_Method_Load Result;
82   memset(&Result, 0, sizeof(iJIT_Method_Load));
83 
84   Result.method_id = Wrapper.iJIT_GetNewMethodID();
85   Result.method_name = const_cast<char*>(FnName);
86   Result.method_load_address = reinterpret_cast<void*>(FnStart);
87   Result.method_size = FnSize;
88 
89   Result.class_id = 0;
90   Result.class_file_name = NULL;
91   Result.user_data = NULL;
92   Result.user_data_size = 0;
93   Result.env = iJDE_JittingAPI;
94 
95   return Result;
96 }
97 
98 void IntelJITEventListener::notifyObjectLoaded(
99     ObjectKey Key, const ObjectFile &Obj,
100     const RuntimeDyld::LoadedObjectInfo &L) {
101 
102   OwningBinary<ObjectFile> DebugObjOwner = L.getObjectForDebug(Obj);
103   const ObjectFile *DebugObj = DebugObjOwner.getBinary();
104   if (!DebugObj)
105     return;
106 
107   // Get the address of the object image for use as a unique identifier
108   const void* ObjData = DebugObj->getData().data();
109   std::unique_ptr<DIContext> Context = DWARFContext::create(*DebugObj);
110   MethodAddressVector Functions;
111 
112   // Use symbol info to iterate functions in the object.
113   for (const std::pair<SymbolRef, uint64_t> &P : computeSymbolSizes(*DebugObj)) {
114     SymbolRef Sym = P.first;
115     std::vector<LineNumberInfo> LineInfo;
116     std::string SourceFileName;
117 
118     Expected<SymbolRef::Type> SymTypeOrErr = Sym.getType();
119     if (!SymTypeOrErr) {
120       // TODO: Actually report errors helpfully.
121       consumeError(SymTypeOrErr.takeError());
122       continue;
123     }
124     SymbolRef::Type SymType = *SymTypeOrErr;
125     if (SymType != SymbolRef::ST_Function)
126       continue;
127 
128     Expected<StringRef> Name = Sym.getName();
129     if (!Name) {
130       // TODO: Actually report errors helpfully.
131       consumeError(Name.takeError());
132       continue;
133     }
134 
135     Expected<uint64_t> AddrOrErr = Sym.getAddress();
136     if (!AddrOrErr) {
137       // TODO: Actually report errors helpfully.
138       consumeError(AddrOrErr.takeError());
139       continue;
140     }
141     uint64_t Addr = *AddrOrErr;
142     uint64_t Size = P.second;
143 
144     auto SecOrErr = Sym.getSection();
145     if (!SecOrErr) {
146       // TODO: Actually report errors helpfully.
147       consumeError(SecOrErr.takeError());
148       continue;
149     }
150     object::section_iterator Sec = *SecOrErr;
151     if (Sec == Obj.section_end())
152       continue;
153     uint64_t Index = Sec->getIndex();
154 
155     // Record this address in a local vector
156     Functions.push_back((void*)Addr);
157 
158     // Build the function loaded notification message
159     iJIT_Method_Load FunctionMessage =
160       FunctionDescToIntelJITFormat(*Wrapper, Name->data(), Addr, Size);
161     DILineInfoTable Lines =
162       Context->getLineInfoForAddressRange({Addr, Index}, Size);
163     DILineInfoTable::iterator Begin = Lines.begin();
164     DILineInfoTable::iterator End = Lines.end();
165     for (DILineInfoTable::iterator It = Begin; It != End; ++It) {
166       LineInfo.push_back(
167           DILineInfoToIntelJITFormat((uintptr_t)Addr, It->first, It->second));
168     }
169     if (LineInfo.size() == 0) {
170       FunctionMessage.source_file_name = 0;
171       FunctionMessage.line_number_size = 0;
172       FunctionMessage.line_number_table = 0;
173     } else {
174       // Source line information for the address range is provided as
175       // a code offset for the start of the corresponding sub-range and
176       // a source line. JIT API treats offsets in LineNumberInfo structures
177       // as the end of the corresponding code region. The start of the code
178       // is taken from the previous element. Need to shift the elements.
179 
180       LineNumberInfo last = LineInfo.back();
181       last.Offset = FunctionMessage.method_size;
182       LineInfo.push_back(last);
183       for (size_t i = LineInfo.size() - 2; i > 0; --i)
184         LineInfo[i].LineNumber = LineInfo[i - 1].LineNumber;
185 
186       SourceFileName = Lines.front().second.FileName;
187       FunctionMessage.source_file_name =
188         const_cast<char *>(SourceFileName.c_str());
189       FunctionMessage.line_number_size = LineInfo.size();
190       FunctionMessage.line_number_table = &*LineInfo.begin();
191     }
192 
193     Wrapper->iJIT_NotifyEvent(iJVM_EVENT_TYPE_METHOD_LOAD_FINISHED,
194                               &FunctionMessage);
195     MethodIDs[(void*)Addr] = FunctionMessage.method_id;
196   }
197 
198   // To support object unload notification, we need to keep a list of
199   // registered function addresses for each loaded object.  We will
200   // use the MethodIDs map to get the registered ID for each function.
201   LoadedObjectMap[ObjData] = Functions;
202   DebugObjects[Key] = std::move(DebugObjOwner);
203 }
204 
205 void IntelJITEventListener::notifyFreeingObject(ObjectKey Key) {
206   // This object may not have been registered with the listener. If it wasn't,
207   // bail out.
208   if (DebugObjects.find(Key) == DebugObjects.end())
209     return;
210 
211   // Get the address of the object image for use as a unique identifier
212   const ObjectFile &DebugObj = *DebugObjects[Key].getBinary();
213   const void* ObjData = DebugObj.getData().data();
214 
215   // Get the object's function list from LoadedObjectMap
216   ObjectMap::iterator OI = LoadedObjectMap.find(ObjData);
217   if (OI == LoadedObjectMap.end())
218     return;
219   MethodAddressVector& Functions = OI->second;
220 
221   // Walk the function list, unregistering each function
222   for (MethodAddressVector::iterator FI = Functions.begin(),
223                                      FE = Functions.end();
224        FI != FE;
225        ++FI) {
226     void* FnStart = const_cast<void*>(*FI);
227     MethodIDMap::iterator MI = MethodIDs.find(FnStart);
228     if (MI != MethodIDs.end()) {
229       Wrapper->iJIT_NotifyEvent(iJVM_EVENT_TYPE_METHOD_UNLOAD_START,
230                                 &MI->second);
231       MethodIDs.erase(MI);
232     }
233   }
234 
235   // Erase the object from LoadedObjectMap
236   LoadedObjectMap.erase(OI);
237   DebugObjects.erase(Key);
238 }
239 
240 }  // anonymous namespace.
241 
242 namespace llvm {
243 JITEventListener *JITEventListener::createIntelJITEventListener() {
244   return new IntelJITEventListener(new IntelJITEventsWrapper);
245 }
246 
247 // for testing
248 JITEventListener *JITEventListener::createIntelJITEventListener(
249                                       IntelJITEventsWrapper* TestImpl) {
250   return new IntelJITEventListener(TestImpl);
251 }
252 
253 } // namespace llvm
254 
255 LLVMJITEventListenerRef LLVMCreateIntelJITEventListener(void)
256 {
257   return wrap(JITEventListener::createIntelJITEventListener());
258 }
259