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