lib/Remarks/RemarkStringTable.cpp

   1 //===- RemarkStringTable.cpp ----------------------------------------------===//
   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 // Implementation of the Remark string table used at remark generation.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "llvm/Remarks/RemarkStringTable.h"
  14 #include "llvm/Remarks/RemarkParser.h"
  15 #include "llvm/Support/EndianStream.h"
  16 #include "llvm/Support/Error.h"
  17 #include <vector>
  18
  19 using namespace llvm;
  20 using namespace llvm::remarks;
  21
  22 StringTable::StringTable(const ParsedStringTable &Other) : StrTab() {
  23   for (unsigned i = 0, e = Other.size(); i < e; ++i)
  24     if (Expected<StringRef> MaybeStr = Other[i])
  25       add(*MaybeStr);
  26     else
  27       llvm_unreachable("Unexpected error while building remarks string table.");
  28 }
  29
  30 std::pair<unsigned, StringRef> StringTable::add(StringRef Str) {
  31   size_t NextID = StrTab.size();
  32   auto KV = StrTab.insert({Str, NextID});
  33   // If it's a new string, add it to the final size.
  34   if (KV.second)
  35     SerializedSize += KV.first->first().size() + 1; // +1 for the '\0'
  36   // Can be either NextID or the previous ID if the string is already there.
  37   return {KV.first->second, KV.first->first()};
  38 }
  39
  40 void StringTable::serialize(raw_ostream &OS) const {
  41   // Emit the sequence of strings.
  42   for (StringRef Str : serialize()) {
  43     OS << Str;
  44     // Explicitly emit a '\0'.
  45     OS.write('\0');
  46   }
  47 }
  48
  49 std::vector<StringRef> StringTable::serialize() const {
  50   std::vector<StringRef> Strings{StrTab.size()};
  51   for (const auto &KV : StrTab)
  52     Strings[KV.second] = KV.first();
  53   return Strings;
  54 }