1 //===- NamedStreamMap.cpp - PDB Named Stream Map --------------------------===// 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 #include "llvm/DebugInfo/PDB/Native/NamedStreamMap.h" 10 #include "llvm/ADT/StringMap.h" 11 #include "llvm/ADT/StringRef.h" 12 #include "llvm/DebugInfo/PDB/Native/Hash.h" 13 #include "llvm/DebugInfo/PDB/Native/HashTable.h" 14 #include "llvm/DebugInfo/PDB/Native/RawError.h" 15 #include "llvm/Support/BinaryStreamReader.h" 16 #include "llvm/Support/BinaryStreamWriter.h" 17 #include "llvm/Support/Endian.h" 18 #include "llvm/Support/Error.h" 19 #include <algorithm> 20 #include <cassert> 21 #include <cstdint> 22 23 using namespace llvm; 24 using namespace llvm::pdb; 25 26 NamedStreamMapTraits::NamedStreamMapTraits(NamedStreamMap &NS) : NS(&NS) {} 27 28 uint16_t NamedStreamMapTraits::hashLookupKey(StringRef S) const { 29 // In the reference implementation, this uses 30 // HASH Hasher<ULONG*, USHORT*>::hashPbCb(PB pb, size_t cb, ULONG ulMod). 31 // Here, the type HASH is a typedef of unsigned short. 32 // ** It is not a bug that we truncate the result of hashStringV1, in fact 33 // it is a bug if we do not! ** 34 // See NMTNI::hash() in the reference implementation. 35 return static_cast<uint16_t>(hashStringV1(S)); 36 } 37 38 StringRef NamedStreamMapTraits::storageKeyToLookupKey(uint32_t Offset) const { 39 return NS->getString(Offset); 40 } 41 42 uint32_t NamedStreamMapTraits::lookupKeyToStorageKey(StringRef S) { 43 return NS->appendStringData(S); 44 } 45 46 NamedStreamMap::NamedStreamMap() : HashTraits(*this), OffsetIndexMap(1) {} 47 48 Error NamedStreamMap::load(BinaryStreamReader &Stream) { 49 uint32_t StringBufferSize; 50 if (auto EC = Stream.readInteger(StringBufferSize)) 51 return joinErrors(std::move(EC), 52 make_error<RawError>(raw_error_code::corrupt_file, 53 "Expected string buffer size")); 54 55 StringRef Buffer; 56 if (auto EC = Stream.readFixedString(Buffer, StringBufferSize)) 57 return EC; 58 NamesBuffer.assign(Buffer.begin(), Buffer.end()); 59 60 return OffsetIndexMap.load(Stream); 61 } 62 63 Error NamedStreamMap::commit(BinaryStreamWriter &Writer) const { 64 // The first field is the number of bytes of string data. 65 if (auto EC = Writer.writeInteger<uint32_t>(NamesBuffer.size())) 66 return EC; 67 68 // Then the actual string data. 69 StringRef Data(NamesBuffer.data(), NamesBuffer.size()); 70 if (auto EC = Writer.writeFixedString(Data)) 71 return EC; 72 73 // And finally the Offset Index map. 74 if (auto EC = OffsetIndexMap.commit(Writer)) 75 return EC; 76 77 return Error::success(); 78 } 79 80 uint32_t NamedStreamMap::calculateSerializedLength() const { 81 return sizeof(uint32_t) // String data size 82 + NamesBuffer.size() // String data 83 + OffsetIndexMap.calculateSerializedLength(); // Offset Index Map 84 } 85 86 uint32_t NamedStreamMap::size() const { return OffsetIndexMap.size(); } 87 88 StringRef NamedStreamMap::getString(uint32_t Offset) const { 89 assert(NamesBuffer.size() > Offset); 90 return StringRef(NamesBuffer.data() + Offset); 91 } 92 93 uint32_t NamedStreamMap::hashString(uint32_t Offset) const { 94 return hashStringV1(getString(Offset)); 95 } 96 97 bool NamedStreamMap::get(StringRef Stream, uint32_t &StreamNo) const { 98 auto Iter = OffsetIndexMap.find_as(Stream, HashTraits); 99 if (Iter == OffsetIndexMap.end()) 100 return false; 101 StreamNo = (*Iter).second; 102 return true; 103 } 104 105 StringMap<uint32_t> NamedStreamMap::entries() const { 106 StringMap<uint32_t> Result; 107 for (const auto &Entry : OffsetIndexMap) { 108 StringRef Stream(NamesBuffer.data() + Entry.first); 109 Result.try_emplace(Stream, Entry.second); 110 } 111 return Result; 112 } 113 114 uint32_t NamedStreamMap::appendStringData(StringRef S) { 115 uint32_t Offset = NamesBuffer.size(); 116 llvm::append_range(NamesBuffer, S); 117 NamesBuffer.push_back('\0'); 118 return Offset; 119 } 120 121 void NamedStreamMap::set(StringRef Stream, uint32_t StreamNo) { 122 OffsetIndexMap.set_as(Stream, support::ulittle32_t(StreamNo), HashTraits); 123 } 124