lib/ExecutionEngine/Orc/ThreadSafeModule.cpp

   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(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