1 //===--- OrcLazyJIT.h - Basic Orc-based JIT for lazy execution --*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Simple Orc-based JIT. Uses the compile-on-demand layer to break up and
11 // lazily compile modules.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_TOOLS_LLI_ORCLAZYJIT_H
16 #define LLVM_TOOLS_LLI_ORCLAZYJIT_H
17 
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/ExecutionEngine/Orc/CompileOnDemandLayer.h"
20 #include "llvm/ExecutionEngine/Orc/CompileUtils.h"
21 #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
22 #include "llvm/ExecutionEngine/Orc/IRCompileLayer.h"
23 #include "llvm/ExecutionEngine/Orc/IRTransformLayer.h"
24 #include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
25 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
26 
27 namespace llvm {
28 
29 class OrcLazyJIT {
30 public:
31 
32   typedef orc::JITCompileCallbackManager CompileCallbackMgr;
33   typedef orc::ObjectLinkingLayer<> ObjLayerT;
34   typedef orc::IRCompileLayer<ObjLayerT> CompileLayerT;
35   typedef std::function<std::unique_ptr<Module>(std::unique_ptr<Module>)>
36     TransformFtor;
37   typedef orc::IRTransformLayer<CompileLayerT, TransformFtor> IRDumpLayerT;
38   typedef orc::CompileOnDemandLayer<IRDumpLayerT, CompileCallbackMgr> CODLayerT;
39   typedef CODLayerT::IndirectStubsManagerBuilderT
40     IndirectStubsManagerBuilder;
41   typedef CODLayerT::ModuleSetHandleT ModuleHandleT;
42 
OrcLazyJIT(std::unique_ptr<TargetMachine> TM,std::unique_ptr<CompileCallbackMgr> CCMgr,IndirectStubsManagerBuilder IndirectStubsMgrBuilder,bool InlineStubs)43   OrcLazyJIT(std::unique_ptr<TargetMachine> TM,
44              std::unique_ptr<CompileCallbackMgr> CCMgr,
45              IndirectStubsManagerBuilder IndirectStubsMgrBuilder,
46              bool InlineStubs)
47       : TM(std::move(TM)), DL(this->TM->createDataLayout()),
48 	CCMgr(std::move(CCMgr)),
49 	ObjectLayer(),
50         CompileLayer(ObjectLayer, orc::SimpleCompiler(*this->TM)),
51         IRDumpLayer(CompileLayer, createDebugDumper()),
52         CODLayer(IRDumpLayer, extractSingleFunction, *this->CCMgr,
53                  std::move(IndirectStubsMgrBuilder), InlineStubs),
54         CXXRuntimeOverrides(
55             [this](const std::string &S) { return mangle(S); }) {}
56 
~OrcLazyJIT()57   ~OrcLazyJIT() {
58     // Run any destructors registered with __cxa_atexit.
59     CXXRuntimeOverrides.runDestructors();
60     // Run any IR destructors.
61     for (auto &DtorRunner : IRStaticDestructorRunners)
62       DtorRunner.runViaLayer(CODLayer);
63   }
64 
addModule(std::unique_ptr<Module> M)65   ModuleHandleT addModule(std::unique_ptr<Module> M) {
66     // Attach a data-layout if one isn't already present.
67     if (M->getDataLayout().isDefault())
68       M->setDataLayout(DL);
69 
70     // Record the static constructors and destructors. We have to do this before
71     // we hand over ownership of the module to the JIT.
72     std::vector<std::string> CtorNames, DtorNames;
73     for (auto Ctor : orc::getConstructors(*M))
74       CtorNames.push_back(mangle(Ctor.Func->getName()));
75     for (auto Dtor : orc::getDestructors(*M))
76       DtorNames.push_back(mangle(Dtor.Func->getName()));
77 
78     // Symbol resolution order:
79     //   1) Search the JIT symbols.
80     //   2) Check for C++ runtime overrides.
81     //   3) Search the host process (LLI)'s symbol table.
82     auto Resolver =
83       orc::createLambdaResolver(
84         [this](const std::string &Name) {
85           if (auto Sym = CODLayer.findSymbol(Name, true))
86             return Sym.toRuntimeDyldSymbol();
87           if (auto Sym = CXXRuntimeOverrides.searchOverrides(Name))
88             return Sym;
89 
90           if (auto Addr =
91               RTDyldMemoryManager::getSymbolAddressInProcess(Name))
92             return RuntimeDyld::SymbolInfo(Addr, JITSymbolFlags::Exported);
93 
94           return RuntimeDyld::SymbolInfo(nullptr);
95         },
96         [](const std::string &Name) {
97           return RuntimeDyld::SymbolInfo(nullptr);
98         }
99       );
100 
101     // Add the module to the JIT.
102     std::vector<std::unique_ptr<Module>> S;
103     S.push_back(std::move(M));
104     auto H = CODLayer.addModuleSet(std::move(S),
105 				   llvm::make_unique<SectionMemoryManager>(),
106 				   std::move(Resolver));
107 
108     // Run the static constructors, and save the static destructor runner for
109     // execution when the JIT is torn down.
110     orc::CtorDtorRunner<CODLayerT> CtorRunner(std::move(CtorNames), H);
111     CtorRunner.runViaLayer(CODLayer);
112 
113     IRStaticDestructorRunners.emplace_back(std::move(DtorNames), H);
114 
115     return H;
116   }
117 
findSymbol(const std::string & Name)118   orc::JITSymbol findSymbol(const std::string &Name) {
119     return CODLayer.findSymbol(mangle(Name), true);
120   }
121 
findSymbolIn(ModuleHandleT H,const std::string & Name)122   orc::JITSymbol findSymbolIn(ModuleHandleT H, const std::string &Name) {
123     return CODLayer.findSymbolIn(H, mangle(Name), true);
124   }
125 
126 private:
127 
mangle(const std::string & Name)128   std::string mangle(const std::string &Name) {
129     std::string MangledName;
130     {
131       raw_string_ostream MangledNameStream(MangledName);
132       Mangler::getNameWithPrefix(MangledNameStream, Name, DL);
133     }
134     return MangledName;
135   }
136 
extractSingleFunction(Function & F)137   static std::set<Function*> extractSingleFunction(Function &F) {
138     std::set<Function*> Partition;
139     Partition.insert(&F);
140     return Partition;
141   }
142 
143   static TransformFtor createDebugDumper();
144 
145   std::unique_ptr<TargetMachine> TM;
146   DataLayout DL;
147   SectionMemoryManager CCMgrMemMgr;
148 
149   std::unique_ptr<CompileCallbackMgr> CCMgr;
150   ObjLayerT ObjectLayer;
151   CompileLayerT CompileLayer;
152   IRDumpLayerT IRDumpLayer;
153   CODLayerT CODLayer;
154 
155   orc::LocalCXXRuntimeOverrides CXXRuntimeOverrides;
156   std::vector<orc::CtorDtorRunner<CODLayerT>> IRStaticDestructorRunners;
157 };
158 
159 int runOrcLazyJIT(std::unique_ptr<Module> M, int ArgC, char* ArgV[]);
160 
161 } // end namespace llvm
162 
163 #endif
164