1 //===-- BitcodeWriterPass.h - Bitcode writing pass --------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 /// \file
10 ///
11 /// This file provides a bitcode writing pass.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_BITCODE_BITCODEWRITERPASS_H
16 #define LLVM_BITCODE_BITCODEWRITERPASS_H
17 
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/IR/PassManager.h"
20 
21 namespace llvm {
22 class Module;
23 class ModulePass;
24 class Pass;
25 class raw_ostream;
26 
27 /// Create and return a pass that writes the module to the specified
28 /// ostream. Note that this pass is designed for use with the legacy pass
29 /// manager.
30 ///
31 /// If \c ShouldPreserveUseListOrder, encode use-list order so it can be
32 /// reproduced when deserialized.
33 ///
34 /// If \c EmitSummaryIndex, emit the summary index (currently for use in ThinLTO
35 /// optimization).
36 ///
37 /// If \c EmitModuleHash, compute and emit the module hash in the bitcode
38 /// (currently for use in ThinLTO incremental build).
39 ModulePass *createBitcodeWriterPass(raw_ostream &Str,
40                                     bool ShouldPreserveUseListOrder = false,
41                                     bool EmitSummaryIndex = false,
42                                     bool EmitModuleHash = false);
43 
44 /// Check whether a pass is a BitcodeWriterPass.
45 bool isBitcodeWriterPass(Pass *P);
46 
47 /// Pass for writing a module of IR out to a bitcode file.
48 ///
49 /// Note that this is intended for use with the new pass manager. To construct
50 /// a pass for the legacy pass manager, use the function above.
51 class BitcodeWriterPass : public PassInfoMixin<BitcodeWriterPass> {
52   raw_ostream &OS;
53   bool ShouldPreserveUseListOrder;
54   bool EmitSummaryIndex;
55   bool EmitModuleHash;
56 
57 public:
58   /// Construct a bitcode writer pass around a particular output stream.
59   ///
60   /// If \c ShouldPreserveUseListOrder, encode use-list order so it can be
61   /// reproduced when deserialized.
62   ///
63   /// If \c EmitSummaryIndex, emit the summary index (currently
64   /// for use in ThinLTO optimization).
65   explicit BitcodeWriterPass(raw_ostream &OS,
66                              bool ShouldPreserveUseListOrder = false,
67                              bool EmitSummaryIndex = false,
68                              bool EmitModuleHash = false)
OS(OS)69       : OS(OS), ShouldPreserveUseListOrder(ShouldPreserveUseListOrder),
70   EmitSummaryIndex(EmitSummaryIndex), EmitModuleHash(EmitModuleHash) {}
71 
72   /// Run the bitcode writer pass, and output the module to the selected
73   /// output stream.
74   PreservedAnalyses run(Module &M, ModuleAnalysisManager &);
75 };
76 
77 }
78 
79 #endif
80