1//===- CommonLinkerContext.h ------------------------------------*- 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// Entry point for all global state in lldCommon. The objective is for LLD to be 10// used "as a library" in a thread-safe manner. 11// 12// Instead of program-wide globals or function-local statics, we prefer 13// aggregating all "global" states into a heap-based structure 14// (CommonLinkerContext). This also achieves deterministic initialization & 15// shutdown for all "global" states. 16// 17//===----------------------------------------------------------------------===// 18 19#ifndef LLD_COMMON_COMMONLINKINGCONTEXT_H 20#define LLD_COMMON_COMMONLINKINGCONTEXT_H 21 22#include "lld/Common/ErrorHandler.h" 23#include "lld/Common/Memory.h" 24#include "llvm/Support/StringSaver.h" 25 26namespace llvm { 27class raw_ostream; 28} // namespace llvm 29 30namespace lld { 31struct SpecificAllocBase; 32class CommonLinkerContext { 33public: 34 CommonLinkerContext(); 35 virtual ~CommonLinkerContext(); 36 37 static void destroy(); 38 39 llvm::BumpPtrAllocator bAlloc; 40 llvm::StringSaver saver{bAlloc}; 41 llvm::DenseMap<void *, SpecificAllocBase *> instances; 42 43 ErrorHandler e; 44}; 45 46// Retrieve the global state. Currently only one state can exist per process, 47// but in the future we plan on supporting an arbitrary number of LLD instances 48// in a single process. 49CommonLinkerContext &commonContext(); 50 51template <typename T = CommonLinkerContext> T &context() { 52 return static_cast<T &>(commonContext()); 53} 54 55bool hasContext(); 56 57inline llvm::StringSaver &saver() { return context().saver; } 58inline llvm::BumpPtrAllocator &bAlloc() { return context().bAlloc; } 59} // namespace lld 60 61#endif 62