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/ADT/iterator_range.h"
13 #include "llvm/DebugInfo/PDB/Native/Hash.h"
14 #include "llvm/DebugInfo/PDB/Native/HashTable.h"
15 #include "llvm/DebugInfo/PDB/Native/RawError.h"
16 #include "llvm/Support/BinaryStreamReader.h"
17 #include "llvm/Support/BinaryStreamRef.h"
18 #include "llvm/Support/BinaryStreamWriter.h"
19 #include "llvm/Support/Endian.h"
20 #include "llvm/Support/Error.h"
21 #include <algorithm>
22 #include <cassert>
23 #include <cstdint>
24 #include <tuple>
25
26 using namespace llvm;
27 using namespace llvm::pdb;
28
NamedStreamMapTraits(NamedStreamMap & NS)29 NamedStreamMapTraits::NamedStreamMapTraits(NamedStreamMap &NS) : NS(&NS) {}
30
hashLookupKey(StringRef S) const31 uint16_t NamedStreamMapTraits::hashLookupKey(StringRef S) const {
32 // In the reference implementation, this uses
33 // HASH Hasher<ULONG*, USHORT*>::hashPbCb(PB pb, size_t cb, ULONG ulMod).
34 // Here, the type HASH is a typedef of unsigned short.
35 // ** It is not a bug that we truncate the result of hashStringV1, in fact
36 // it is a bug if we do not! **
37 // See NMTNI::hash() in the reference implementation.
38 return static_cast<uint16_t>(hashStringV1(S));
39 }
40
storageKeyToLookupKey(uint32_t Offset) const41 StringRef NamedStreamMapTraits::storageKeyToLookupKey(uint32_t Offset) const {
42 return NS->getString(Offset);
43 }
44
lookupKeyToStorageKey(StringRef S)45 uint32_t NamedStreamMapTraits::lookupKeyToStorageKey(StringRef S) {
46 return NS->appendStringData(S);
47 }
48
NamedStreamMap()49 NamedStreamMap::NamedStreamMap() : HashTraits(*this), OffsetIndexMap(1) {}
50
load(BinaryStreamReader & Stream)51 Error NamedStreamMap::load(BinaryStreamReader &Stream) {
52 uint32_t StringBufferSize;
53 if (auto EC = Stream.readInteger(StringBufferSize))
54 return joinErrors(std::move(EC),
55 make_error<RawError>(raw_error_code::corrupt_file,
56 "Expected string buffer size"));
57
58 StringRef Buffer;
59 if (auto EC = Stream.readFixedString(Buffer, StringBufferSize))
60 return EC;
61 NamesBuffer.assign(Buffer.begin(), Buffer.end());
62
63 return OffsetIndexMap.load(Stream);
64 }
65
commit(BinaryStreamWriter & Writer) const66 Error NamedStreamMap::commit(BinaryStreamWriter &Writer) const {
67 // The first field is the number of bytes of string data.
68 if (auto EC = Writer.writeInteger<uint32_t>(NamesBuffer.size()))
69 return EC;
70
71 // Then the actual string data.
72 StringRef Data(NamesBuffer.data(), NamesBuffer.size());
73 if (auto EC = Writer.writeFixedString(Data))
74 return EC;
75
76 // And finally the Offset Index map.
77 if (auto EC = OffsetIndexMap.commit(Writer))
78 return EC;
79
80 return Error::success();
81 }
82
calculateSerializedLength() const83 uint32_t NamedStreamMap::calculateSerializedLength() const {
84 return sizeof(uint32_t) // String data size
85 + NamesBuffer.size() // String data
86 + OffsetIndexMap.calculateSerializedLength(); // Offset Index Map
87 }
88
size() const89 uint32_t NamedStreamMap::size() const { return OffsetIndexMap.size(); }
90
getString(uint32_t Offset) const91 StringRef NamedStreamMap::getString(uint32_t Offset) const {
92 assert(NamesBuffer.size() > Offset);
93 return StringRef(NamesBuffer.data() + Offset);
94 }
95
hashString(uint32_t Offset) const96 uint32_t NamedStreamMap::hashString(uint32_t Offset) const {
97 return hashStringV1(getString(Offset));
98 }
99
get(StringRef Stream,uint32_t & StreamNo) const100 bool NamedStreamMap::get(StringRef Stream, uint32_t &StreamNo) const {
101 auto Iter = OffsetIndexMap.find_as(Stream, HashTraits);
102 if (Iter == OffsetIndexMap.end())
103 return false;
104 StreamNo = (*Iter).second;
105 return true;
106 }
107
entries() const108 StringMap<uint32_t> NamedStreamMap::entries() const {
109 StringMap<uint32_t> Result;
110 for (const auto &Entry : OffsetIndexMap) {
111 StringRef Stream(NamesBuffer.data() + Entry.first);
112 Result.try_emplace(Stream, Entry.second);
113 }
114 return Result;
115 }
116
appendStringData(StringRef S)117 uint32_t NamedStreamMap::appendStringData(StringRef S) {
118 uint32_t Offset = NamesBuffer.size();
119 llvm::append_range(NamesBuffer, S);
120 NamesBuffer.push_back('\0');
121 return Offset;
122 }
123
set(StringRef Stream,uint32_t StreamNo)124 void NamedStreamMap::set(StringRef Stream, uint32_t StreamNo) {
125 OffsetIndexMap.set_as(Stream, support::ulittle32_t(StreamNo), HashTraits);
126 }
127