1 //===--- IncrementalExecutor.cpp - Incremental Execution --------*- C++ -*-===//
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 implements the class which performs incremental code execution.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "IncrementalExecutor.h"
14 
15 #include "clang/Basic/TargetInfo.h"
16 #include "clang/Basic/TargetOptions.h"
17 #include "clang/Interpreter/PartialTranslationUnit.h"
18 #include "llvm/ExecutionEngine/ExecutionEngine.h"
19 #include "llvm/ExecutionEngine/Orc/CompileUtils.h"
20 #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
21 #include "llvm/ExecutionEngine/Orc/IRCompileLayer.h"
22 #include "llvm/ExecutionEngine/Orc/LLJIT.h"
23 #include "llvm/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.h"
24 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
25 #include "llvm/IR/Module.h"
26 #include "llvm/Support/ManagedStatic.h"
27 #include "llvm/Support/TargetSelect.h"
28 
29 namespace clang {
30 
31 IncrementalExecutor::IncrementalExecutor(llvm::orc::ThreadSafeContext &TSC,
32                                          llvm::Error &Err,
33                                          const clang::TargetInfo &TI)
34     : TSCtx(TSC) {
35   using namespace llvm::orc;
36   llvm::ErrorAsOutParameter EAO(&Err);
37 
38   auto JTMB = JITTargetMachineBuilder(TI.getTriple());
39   JTMB.addFeatures(TI.getTargetOpts().Features);
40   if (auto JitOrErr = LLJITBuilder().setJITTargetMachineBuilder(JTMB).create())
41     Jit = std::move(*JitOrErr);
42   else {
43     Err = JitOrErr.takeError();
44     return;
45   }
46 
47   const char Pref = Jit->getDataLayout().getGlobalPrefix();
48   // Discover symbols from the process as a fallback.
49   if (auto PSGOrErr = DynamicLibrarySearchGenerator::GetForCurrentProcess(Pref))
50     Jit->getMainJITDylib().addGenerator(std::move(*PSGOrErr));
51   else {
52     Err = PSGOrErr.takeError();
53     return;
54   }
55 }
56 
57 IncrementalExecutor::~IncrementalExecutor() {}
58 
59 llvm::Error IncrementalExecutor::addModule(PartialTranslationUnit &PTU) {
60   llvm::orc::ResourceTrackerSP RT =
61       Jit->getMainJITDylib().createResourceTracker();
62   ResourceTrackers[&PTU] = RT;
63 
64   return Jit->addIRModule(RT, {std::move(PTU.TheModule), TSCtx});
65 }
66 
67 llvm::Error IncrementalExecutor::removeModule(PartialTranslationUnit &PTU) {
68 
69   llvm::orc::ResourceTrackerSP RT = std::move(ResourceTrackers[&PTU]);
70   if (!RT)
71     return llvm::Error::success();
72 
73   ResourceTrackers.erase(&PTU);
74   if (llvm::Error Err = RT->remove())
75     return Err;
76   return llvm::Error::success();
77 }
78 
79 llvm::Error IncrementalExecutor::runCtors() const {
80   return Jit->initialize(Jit->getMainJITDylib());
81 }
82 
83 llvm::Expected<llvm::JITTargetAddress>
84 IncrementalExecutor::getSymbolAddress(llvm::StringRef Name,
85                                       SymbolNameKind NameKind) const {
86   auto Sym = (NameKind == LinkerName) ? Jit->lookupLinkerMangled(Name)
87                                       : Jit->lookup(Name);
88 
89   if (!Sym)
90     return Sym.takeError();
91   return Sym->getValue();
92 }
93 
94 } // end namespace clang
95