lld/Common/CommonLinkerContext.cpp

   1 //===- CommonLinkerContext.cpp --------------------------------------------===//
   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 #include "lld/Common/CommonLinkerContext.h"
  10 #include "lld/Common/ErrorHandler.h"
  11 #include "lld/Common/Memory.h"
  12
  13 #include "llvm/CodeGen/CommandFlags.h"
  14
  15 using namespace llvm;
  16 using namespace lld;
  17
  18 // Reference to the current LLD instance. This is a temporary situation, until
  19 // we pass this context everywhere by reference, or we make it a thread_local,
  20 // as in https://reviews.llvm.org/D108850?id=370678 where each thread can be
  21 // associated with a LLD instance. Only then will LLD be free of global
  22 // state.
  23 static CommonLinkerContext *lctx;
  24
  25 CommonLinkerContext::CommonLinkerContext() {
  26   lctx = this;
  27   // Fire off the static initializations in CGF's constructor.
  28   codegen::RegisterCodeGenFlags CGF;
  29 }
  30
  31 CommonLinkerContext::~CommonLinkerContext() {
  32   assert(lctx);
  33   // Explicitly call the destructors since we created the objects with placement
  34   // new in SpecificAlloc::create().
  35   for (auto &it : instances)
  36     it.second->~SpecificAllocBase();
  37   lctx = nullptr;
  38 }
  39
  40 CommonLinkerContext &lld::commonContext() {
  41   assert(lctx);
  42   return *lctx;
  43 }
  44
  45 bool lld::hasContext() { return lctx != nullptr; }
  46
  47 void CommonLinkerContext::destroy() {
  48   if (lctx == nullptr)
  49     return;
  50   delete lctx;
  51 }