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   auto Lock = TSM.getContextLock();
  27
  28   SmallVector<char, 1> ClonedModuleBuffer;
  29
  30   {
  31     std::set<GlobalValue *> ClonedDefsInSrc;
  32     ValueToValueMapTy VMap;
  33     auto Tmp = CloneModule(*TSM.getModule(), VMap, [&](const GlobalValue *GV) {
  34       if (ShouldCloneDef(*GV)) {
  35         ClonedDefsInSrc.insert(const_cast<GlobalValue *>(GV));
  36         return true;
  37       }
  38       return false;
  39     });
  40
  41     if (UpdateClonedDefSource)
  42       for (auto *GV : ClonedDefsInSrc)
  43         UpdateClonedDefSource(*GV);
  44
  45     BitcodeWriter BCWriter(ClonedModuleBuffer);
  46
  47     BCWriter.writeModule(*Tmp);
  48     BCWriter.writeSymtab();
  49     BCWriter.writeStrtab();
  50   }
  51
  52   MemoryBufferRef ClonedModuleBufferRef(
  53       StringRef(ClonedModuleBuffer.data(), ClonedModuleBuffer.size()),
  54       "cloned module buffer");
  55   ThreadSafeContext NewTSCtx(llvm::make_unique<LLVMContext>());
  56
  57   auto ClonedModule =
  58       cantFail(parseBitcodeFile(ClonedModuleBufferRef, *NewTSCtx.getContext()));
  59   ClonedModule->setModuleIdentifier(TSM.getModule()->getName());
  60   return ThreadSafeModule(std::move(ClonedModule), std::move(NewTSCtx));
  61 }
  62
  63 } // end namespace orc
  64 } // end namespace llvm