include/llvm/Remarks/BitstreamRemarkParser.h

   1 //===-- BitstreamRemarkParser.h - Bitstream parser --------------*- 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 // This file provides an implementation of the remark parser using the LLVM
  10 // Bitstream format.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_REMARKS_BITSTREAM_REMARK_PARSER_H
  15 #define LLVM_REMARKS_BITSTREAM_REMARK_PARSER_H
  16
  17 #include "llvm/ADT/StringRef.h"
  18 #include "llvm/Bitstream/BitstreamReader.h"
  19 #include "llvm/Remarks/BitstreamRemarkContainer.h"
  20 #include "llvm/Remarks/Remark.h"
  21 #include "llvm/Remarks/RemarkParser.h"
  22 #include "llvm/Support/Error.h"
  23 #include <array>
  24
  25 namespace llvm {
  26 namespace remarks {
  27
  28 /// Helper to parse a META_BLOCK for a bitstream remark container.
  29 struct BitstreamMetaParserHelper {
  30   /// The Bitstream reader.
  31   BitstreamCursor &Stream;
  32   /// Reference to the storage for the block info.
  33   BitstreamBlockInfo &BlockInfo;
  34   /// The parsed content: depending on the container type, some fields might be
  35   /// empty.
  36   Optional<uint64_t> ContainerVersion;
  37   Optional<uint8_t> ContainerType;
  38   Optional<StringRef> StrTabBuf;
  39   Optional<StringRef> ExternalFilePath;
  40   Optional<uint64_t> RemarkVersion;
  41
  42   /// Continue parsing with \p Stream. \p Stream is expected to contain a
  43   /// ENTER_SUBBLOCK to the META_BLOCK at the current position.
  44   /// \p Stream is expected to have a BLOCKINFO_BLOCK set.
  45   BitstreamMetaParserHelper(BitstreamCursor &Stream,
  46                             BitstreamBlockInfo &BlockInfo);
  47
  48   /// Parse the META_BLOCK and fill the available entries.
  49   /// This helper does not check for the validity of the fields.
  50   Error parse();
  51 };
  52
  53 /// Helper to parse a REMARK_BLOCK for a bitstream remark container.
  54 struct BitstreamRemarkParserHelper {
  55   /// The Bitstream reader.
  56   BitstreamCursor &Stream;
  57   /// The parsed content: depending on the remark, some fields might be empty.
  58   Optional<uint8_t> Type;
  59   Optional<uint64_t> RemarkNameIdx;
  60   Optional<uint64_t> PassNameIdx;
  61   Optional<uint64_t> FunctionNameIdx;
  62   Optional<uint64_t> SourceFileNameIdx;
  63   Optional<uint32_t> SourceLine;
  64   Optional<uint32_t> SourceColumn;
  65   Optional<uint64_t> Hotness;
  66   struct Argument {
  67     Optional<uint64_t> KeyIdx;
  68     Optional<uint64_t> ValueIdx;
  69     Optional<uint64_t> SourceFileNameIdx;
  70     Optional<uint32_t> SourceLine;
  71     Optional<uint32_t> SourceColumn;
  72   };
  73   Optional<ArrayRef<Argument>> Args;
  74   /// Avoid re-allocating a vector every time.
  75   SmallVector<Argument, 8> TmpArgs;
  76
  77   /// Continue parsing with \p Stream. \p Stream is expected to contain a
  78   /// ENTER_SUBBLOCK to the REMARK_BLOCK at the current position.
  79   /// \p Stream is expected to have a BLOCKINFO_BLOCK set and to have already
  80   /// parsed the META_BLOCK.
  81   BitstreamRemarkParserHelper(BitstreamCursor &Stream);
  82
  83   /// Parse the REMARK_BLOCK and fill the available entries.
  84   /// This helper does not check for the validity of the fields.
  85   Error parse();
  86 };
  87
  88 /// Helper to parse any bitstream remark container.
  89 struct BitstreamParserHelper {
  90   /// The Bitstream reader.
  91   BitstreamCursor Stream;
  92   /// The block info block.
  93   BitstreamBlockInfo BlockInfo;
  94   /// Start parsing at \p Buffer.
  95   BitstreamParserHelper(StringRef Buffer);
  96   /// Parse the magic number.
  97   Expected<std::array<char, 4>> parseMagic();
  98   /// Parse the block info block containing all the abbrevs.
  99   /// This needs to be called before calling any other parsing function.
 100   Error parseBlockInfoBlock();
 101   /// Return true if the next block is a META_BLOCK. This function does not move
 102   /// the cursor.
 103   Expected<bool> isMetaBlock();
 104   /// Return true if the next block is a REMARK_BLOCK. This function does not
 105   /// move the cursor.
 106   Expected<bool> isRemarkBlock();
 107   /// Return true if the parser reached the end of the stream.
 108   bool atEndOfStream() { return Stream.AtEndOfStream(); }
 109   /// Jump to the end of the stream, skipping everything.
 110   void skipToEnd() { return Stream.skipToEnd(); }
 111 };
 112
 113 } // end namespace remarks
 114 } // end namespace llvm
 115
 116 #endif /* LLVM_REMARKS_BITSTREAM_REMARK_PARSER_H */