xref: /freebsd/contrib/llvm-project/llvm/include/llvm/LTO/LTOBackend.h (revision 700637cbb5e582861067a11aaca4d053546871d2)
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/Compiler.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Target/TargetOptions.h"
26 #include "llvm/Transforms/IPO/FunctionImport.h"
27 
28 namespace llvm {
29 
30 class BitcodeModule;
31 class Error;
32 class Module;
33 class Target;
34 
35 namespace lto {
36 
37 /// Runs middle-end LTO optimizations on \p Mod.
38 LLVM_ABI bool opt(const Config &Conf, TargetMachine *TM, unsigned Task,
39                   Module &Mod, bool IsThinLTO,
40                   ModuleSummaryIndex *ExportSummary,
41                   const ModuleSummaryIndex *ImportSummary,
42                   const std::vector<uint8_t> &CmdArgs);
43 
44 /// Runs a regular LTO backend. The regular LTO backend can also act as the
45 /// regular LTO phase of ThinLTO, which may need to access the combined index.
46 LLVM_ABI Error backend(const Config &C, AddStreamFn AddStream,
47                        unsigned ParallelCodeGenParallelismLevel, Module &M,
48                        ModuleSummaryIndex &CombinedIndex);
49 
50 /// Runs a ThinLTO backend.
51 /// If \p ModuleMap is not nullptr, all the module files to be imported have
52 /// already been mapped to memory and the corresponding BitcodeModule objects
53 /// are saved in the ModuleMap. If \p ModuleMap is nullptr, module files will
54 /// be mapped to memory on demand and at any given time during importing, only
55 /// one source module will be kept open at the most. If \p CodeGenOnly is true,
56 /// the backend will skip optimization and only perform code generation. If
57 /// \p IRAddStream is not nullptr, it will be called just before code generation
58 /// to serialize the optimized IR.
59 LLVM_ABI Error
60 thinBackend(const Config &C, unsigned Task, AddStreamFn AddStream, Module &M,
61             const ModuleSummaryIndex &CombinedIndex,
62             const FunctionImporter::ImportMapTy &ImportList,
63             const GVSummaryMapTy &DefinedGlobals,
64             MapVector<StringRef, BitcodeModule> *ModuleMap, bool CodeGenOnly,
65             AddStreamFn IRAddStream = nullptr,
66             const std::vector<uint8_t> &CmdArgs = std::vector<uint8_t>());
67 
68 LLVM_ABI Error
69 finalizeOptimizationRemarks(std::unique_ptr<ToolOutputFile> DiagOutputFile);
70 
71 /// Returns the BitcodeModule that is ThinLTO.
72 LLVM_ABI BitcodeModule *findThinLTOModule(MutableArrayRef<BitcodeModule> BMs);
73 
74 /// Variant of the above.
75 LLVM_ABI Expected<BitcodeModule> findThinLTOModule(MemoryBufferRef MBRef);
76 
77 /// Distributed ThinLTO: collect the referenced modules based on
78 /// module summary and initialize ImportList. Returns false if the
79 /// operation failed.
80 LLVM_ABI bool initImportList(const Module &M,
81                              const ModuleSummaryIndex &CombinedIndex,
82                              FunctionImporter::ImportMapTy &ImportList);
83 }
84 }
85 
86 #endif
87