1 //===-- ThreadSafeModule.cpp - Thread safe Module, Context, and Utilities
2 //h-===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "llvm/ExecutionEngine/Orc/ThreadSafeModule.h"
11 #include "llvm/Bitcode/BitcodeReader.h"
12 #include "llvm/Bitcode/BitcodeWriter.h"
13 #include "llvm/Transforms/Utils/Cloning.h"
14 
15 namespace llvm {
16 namespace orc {
17 
18 ThreadSafeModule cloneToNewContext(const ThreadSafeModule &TSM,
19                                    GVPredicate ShouldCloneDef,
20                                    GVModifier UpdateClonedDefSource) {
21   assert(TSM && "Can not clone null module");
22 
23   if (!ShouldCloneDef)
24     ShouldCloneDef = [](const GlobalValue &) { return true; };
25 
26   return TSM.withModuleDo([&](Module &M) {
27     SmallVector<char, 1> ClonedModuleBuffer;
28 
29     {
30       std::set<GlobalValue *> ClonedDefsInSrc;
31       ValueToValueMapTy VMap;
32       auto Tmp = CloneModule(M, VMap, [&](const GlobalValue *GV) {
33         if (ShouldCloneDef(*GV)) {
34           ClonedDefsInSrc.insert(const_cast<GlobalValue *>(GV));
35           return true;
36         }
37         return false;
38       });
39 
40       if (UpdateClonedDefSource)
41         for (auto *GV : ClonedDefsInSrc)
42           UpdateClonedDefSource(*GV);
43 
44       BitcodeWriter BCWriter(ClonedModuleBuffer);
45 
46       BCWriter.writeModule(*Tmp);
47       BCWriter.writeSymtab();
48       BCWriter.writeStrtab();
49     }
50 
51     MemoryBufferRef ClonedModuleBufferRef(
52         StringRef(ClonedModuleBuffer.data(), ClonedModuleBuffer.size()),
53         "cloned module buffer");
54     ThreadSafeContext NewTSCtx(std::make_unique<LLVMContext>());
55 
56     auto ClonedModule = cantFail(
57         parseBitcodeFile(ClonedModuleBufferRef, *NewTSCtx.getContext()));
58     ClonedModule->setModuleIdentifier(M.getName());
59     return ThreadSafeModule(std::move(ClonedModule), std::move(NewTSCtx));
60   });
61 }
62 
63 } // end namespace orc
64 } // end namespace llvm
65