tools/lli/OrcLazyJIT.h

   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/LazyEmittingLayer.h"
  24 #include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
  25 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
  26 #include "llvm/IR/LLVMContext.h"
  27
  28 namespace llvm {
  29
  30 class OrcLazyJIT {
  31 public:
  32
  33   typedef orc::JITCompileCallbackManagerBase CompileCallbackMgr;
  34   typedef orc::ObjectLinkingLayer<> ObjLayerT;
  35   typedef orc::IRCompileLayer<ObjLayerT> CompileLayerT;
  36   typedef orc::LazyEmittingLayer<CompileLayerT> LazyEmitLayerT;
  37   typedef orc::CompileOnDemandLayer<LazyEmitLayerT,
  38                                     CompileCallbackMgr> CODLayerT;
  39   typedef CODLayerT::ModuleSetHandleT ModuleHandleT;
  40
  41   typedef std::function<
  42             std::unique_ptr<CompileCallbackMgr>(CompileLayerT&,
  43                                                 RuntimeDyld::MemoryManager&,
  44                                                 LLVMContext&)>
  45     CallbackManagerBuilder;
  46
  47   static CallbackManagerBuilder createCallbackManagerBuilder(Triple T);
  48
  49   OrcLazyJIT(std::unique_ptr<TargetMachine> TM, LLVMContext &Context,
  50              CallbackManagerBuilder &BuildCallbackMgr)
  51     : TM(std::move(TM)),
  52       Mang(this->TM->getDataLayout()),
  53       ObjectLayer(),
  54       CompileLayer(ObjectLayer, orc::SimpleCompiler(*this->TM)),
  55       LazyEmitLayer(CompileLayer),
  56       CCMgr(BuildCallbackMgr(CompileLayer, CCMgrMemMgr, Context)),
  57       CODLayer(LazyEmitLayer, *CCMgr),
  58       CXXRuntimeOverrides([this](const std::string &S) { return mangle(S); }) {}
  59
  60   ~OrcLazyJIT() {
  61     // Run any destructors registered with __cxa_atexit.
  62     CXXRuntimeOverrides.runDestructors();
  63     // Run any IR destructors.
  64     for (auto &DtorRunner : IRStaticDestructorRunners)
  65       DtorRunner.runViaLayer(CODLayer);
  66   }
  67
  68   template <typename PtrTy>
  69   static PtrTy fromTargetAddress(orc::TargetAddress Addr) {
  70     return reinterpret_cast<PtrTy>(static_cast<uintptr_t>(Addr));
  71   }
  72
  73   ModuleHandleT addModule(std::unique_ptr<Module> M) {
  74     // Attach a data-layout if one isn't already present.
  75     if (M->getDataLayout().isDefault())
  76       M->setDataLayout(*TM->getDataLayout());
  77
  78     // Record the static constructors and destructors. We have to do this before
  79     // we hand over ownership of the module to the JIT.
  80     std::vector<std::string> CtorNames, DtorNames;
  81     for (auto Ctor : orc::getConstructors(*M))
  82       CtorNames.push_back(mangle(Ctor.Func->getName()));
  83     for (auto Dtor : orc::getDestructors(*M))
  84       DtorNames.push_back(mangle(Dtor.Func->getName()));
  85
  86     // Symbol resolution order:
  87     //   1) Search the JIT symbols.
  88     //   2) Check for C++ runtime overrides.
  89     //   3) Search the host process (LLI)'s symbol table.
  90     auto FallbackLookup =
  91       [this](const std::string &Name) {
  92
  93         if (auto Sym = CODLayer.findSymbol(Name, true))
  94           return RuntimeDyld::SymbolInfo(Sym.getAddress(), Sym.getFlags());
  95
  96         if (auto Sym = CXXRuntimeOverrides.searchOverrides(Name))
  97           return Sym;
  98
  99         if (auto Addr = RTDyldMemoryManager::getSymbolAddressInProcess(Name))
 100           return RuntimeDyld::SymbolInfo(Addr, JITSymbolFlags::Exported);
 101
 102         return RuntimeDyld::SymbolInfo(nullptr);
 103       };
 104
 105     // Add the module to the JIT.
 106     std::vector<std::unique_ptr<Module>> S;
 107     S.push_back(std::move(M));
 108     auto H = CODLayer.addModuleSet(std::move(S), std::move(FallbackLookup));
 109
 110     // Run the static constructors, and save the static destructor runner for
 111     // execution when the JIT is torn down.
 112     orc::CtorDtorRunner<CODLayerT> CtorRunner(std::move(CtorNames), H);
 113     CtorRunner.runViaLayer(CODLayer);
 114
 115     IRStaticDestructorRunners.push_back(
 116         orc::CtorDtorRunner<CODLayerT>(std::move(DtorNames), H));
 117
 118     return H;
 119   }
 120
 121   orc::JITSymbol findSymbol(const std::string &Name) {
 122     return CODLayer.findSymbol(mangle(Name), true);
 123   }
 124
 125   orc::JITSymbol findSymbolIn(ModuleHandleT H, const std::string &Name) {
 126     return CODLayer.findSymbolIn(H, mangle(Name), true);
 127   }
 128
 129 private:
 130
 131   std::string mangle(const std::string &Name) {
 132     std::string MangledName;
 133     {
 134       raw_string_ostream MangledNameStream(MangledName);
 135       Mang.getNameWithPrefix(MangledNameStream, Name);
 136     }
 137     return MangledName;
 138   }
 139
 140   std::unique_ptr<TargetMachine> TM;
 141   Mangler Mang;
 142   SectionMemoryManager CCMgrMemMgr;
 143
 144   ObjLayerT ObjectLayer;
 145   CompileLayerT CompileLayer;
 146   LazyEmitLayerT LazyEmitLayer;
 147   std::unique_ptr<CompileCallbackMgr> CCMgr;
 148   CODLayerT CODLayer;
 149
 150   orc::LocalCXXRuntimeOverrides CXXRuntimeOverrides;
 151   std::vector<orc::CtorDtorRunner<CODLayerT>> IRStaticDestructorRunners;
 152 };
 153
 154 int runOrcLazyJIT(std::unique_ptr<Module> M, int ArgC, char* ArgV[]);
 155
 156 } // end namespace llvm
 157
 158 #endif