llvm/Remarks/RemarkStringTable.h

0001 //===-- RemarkStringTable.h - Serializing string table ----------*- C++/-*-===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008 //
0009 // This class is used to deduplicate and serialize a string table used for
0010 // generating remarks.
0011 //
0012 // For parsing a string table, use ParsedStringTable in RemarkParser.h
0013 //
0014 //===----------------------------------------------------------------------===//
0015
0016 #ifndef LLVM_REMARKS_REMARKSTRINGTABLE_H
0017 #define LLVM_REMARKS_REMARKSTRINGTABLE_H
0018
0019 #include "llvm/ADT/StringMap.h"
0020 #include "llvm/Support/Allocator.h"
0021 #include <vector>
0022
0023 namespace llvm {
0024
0025 class raw_ostream;
0026 class StringRef;
0027
0028 namespace remarks {
0029
0030 struct ParsedStringTable;
0031 struct Remark;
0032
0033 /// The string table used for serializing remarks.
0034 /// This table can be for example serialized in a section to be consumed after
0035 /// the compilation.
0036 struct StringTable {
0037   /// The string table containing all the unique strings used in the output.
0038   /// It maps a string to an unique ID.
0039   StringMap<unsigned, BumpPtrAllocator> StrTab;
0040   /// Total size of the string table when serialized.
0041   size_t SerializedSize = 0;
0042
0043   StringTable() = default;
0044
0045   /// Disable copy.
0046   StringTable(const StringTable &) = delete;
0047   StringTable &operator=(const StringTable &) = delete;
0048   /// Should be movable.
0049   StringTable(StringTable &&) = default;
0050   StringTable &operator=(StringTable &&) = default;
0051
0052   /// Construct a string table from a ParsedStringTable.
0053   StringTable(const ParsedStringTable &Other);
0054
0055   /// Add a string to the table. It returns an unique ID of the string.
0056   std::pair<unsigned, StringRef> add(StringRef Str);
0057   /// Modify \p R to use strings from this string table. If the string table
0058   /// does not contain the strings, it adds them.
0059   void internalize(Remark &R);
0060   /// Serialize the string table to a stream. It is serialized as a little
0061   /// endian uint64 (the size of the table in bytes) followed by a sequence of
0062   /// NULL-terminated strings, where the N-th string is the string with the ID N
0063   /// in the StrTab map.
0064   void serialize(raw_ostream &OS) const;
0065   /// Serialize the string table to a vector. This allows users to do the actual
0066   /// writing to file/memory/other.
0067   /// The string with the ID == N should be the N-th element in the vector.
0068   std::vector<StringRef> serialize() const;
0069 };
0070
0071 } // end namespace remarks
0072 } // end namespace llvm
0073
0074 #endif // LLVM_REMARKS_REMARKSTRINGTABLE_H