1 //===-LTOBackend.h - LLVM Link Time Optimizer Backend ---------------------===// 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 // This file implements the "backend" phase of LTO, i.e. it performs 10 // optimization and code generation on a loaded module. It is generally used 11 // internally by the LTO class but can also be used independently, for example 12 // to implement a standalone ThinLTO backend. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_LTO_LTOBACKEND_H 17 #define LLVM_LTO_LTOBACKEND_H 18 19 #include "llvm/ADT/MapVector.h" 20 #include "llvm/IR/DiagnosticInfo.h" 21 #include "llvm/IR/ModuleSummaryIndex.h" 22 #include "llvm/LTO/LTO.h" 23 #include "llvm/Support/MemoryBuffer.h" 24 #include "llvm/Target/TargetOptions.h" 25 #include "llvm/Transforms/IPO/FunctionImport.h" 26 27 namespace llvm { 28 29 class BitcodeModule; 30 class Error; 31 class Module; 32 class Target; 33 34 namespace lto { 35 36 /// Runs middle-end LTO optimizations on \p Mod. 37 bool opt(const Config &Conf, TargetMachine *TM, unsigned Task, Module &Mod, 38 bool IsThinLTO, ModuleSummaryIndex *ExportSummary, 39 const ModuleSummaryIndex *ImportSummary, 40 const std::vector<uint8_t> &CmdArgs); 41 42 /// Runs a regular LTO backend. The regular LTO backend can also act as the 43 /// regular LTO phase of ThinLTO, which may need to access the combined index. 44 Error backend(const Config &C, AddStreamFn AddStream, 45 unsigned ParallelCodeGenParallelismLevel, Module &M, 46 ModuleSummaryIndex &CombinedIndex); 47 48 /// Runs a ThinLTO backend. 49 /// If \p ModuleMap is not nullptr, all the module files to be imported have 50 /// already been mapped to memory and the corresponding BitcodeModule objects 51 /// are saved in the ModuleMap. If \p ModuleMap is nullptr, module files will 52 /// be mapped to memory on demand and at any given time during importing, only 53 /// one source module will be kept open at the most. If \p CodeGenOnly is true, 54 /// the backend will skip optimization and only perform code generation. If 55 /// \p IRAddStream is not nullptr, it will be called just before code generation 56 /// to serialize the optimized IR. 57 Error thinBackend(const Config &C, unsigned Task, AddStreamFn AddStream, 58 Module &M, const ModuleSummaryIndex &CombinedIndex, 59 const FunctionImporter::ImportMapTy &ImportList, 60 const GVSummaryMapTy &DefinedGlobals, 61 MapVector<StringRef, BitcodeModule> *ModuleMap, 62 bool CodeGenOnly, AddStreamFn IRAddStream = nullptr, 63 const std::vector<uint8_t> &CmdArgs = std::vector<uint8_t>()); 64 65 Error finalizeOptimizationRemarks( 66 std::unique_ptr<ToolOutputFile> DiagOutputFile); 67 68 /// Returns the BitcodeModule that is ThinLTO. 69 BitcodeModule *findThinLTOModule(MutableArrayRef<BitcodeModule> BMs); 70 71 /// Variant of the above. 72 Expected<BitcodeModule> findThinLTOModule(MemoryBufferRef MBRef); 73 74 /// Distributed ThinLTO: collect the referenced modules based on 75 /// module summary and initialize ImportList. Returns false if the 76 /// operation failed. 77 bool initImportList(const Module &M, const ModuleSummaryIndex &CombinedIndex, 78 FunctionImporter::ImportMapTy &ImportList); 79 } 80 } 81 82 #endif 83