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
NamedStreamMapTraits(NamedStreamMap & NS)26 NamedStreamMapTraits::NamedStreamMapTraits(NamedStreamMap &NS) : NS(&NS) {}
27
hashLookupKey(StringRef S) const28 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
storageKeyToLookupKey(uint32_t Offset) const38 StringRef NamedStreamMapTraits::storageKeyToLookupKey(uint32_t Offset) const {
39 return NS->getString(Offset);
40 }
41
lookupKeyToStorageKey(StringRef S)42 uint32_t NamedStreamMapTraits::lookupKeyToStorageKey(StringRef S) {
43 return NS->appendStringData(S);
44 }
45
NamedStreamMap()46 NamedStreamMap::NamedStreamMap() : HashTraits(*this), OffsetIndexMap(1) {}
47
load(BinaryStreamReader & Stream)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
commit(BinaryStreamWriter & Writer) const63 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
calculateSerializedLength() const80 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
size() const86 uint32_t NamedStreamMap::size() const { return OffsetIndexMap.size(); }
87
getString(uint32_t Offset) const88 StringRef NamedStreamMap::getString(uint32_t Offset) const {
89 assert(NamesBuffer.size() > Offset);
90 return StringRef(NamesBuffer.data() + Offset);
91 }
92
hashString(uint32_t Offset) const93 uint32_t NamedStreamMap::hashString(uint32_t Offset) const {
94 return hashStringV1(getString(Offset));
95 }
96
get(StringRef Stream,uint32_t & StreamNo) const97 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
entries() const105 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
appendStringData(StringRef S)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
set(StringRef Stream,uint32_t StreamNo)121 void NamedStreamMap::set(StringRef Stream, uint32_t StreamNo) {
122 OffsetIndexMap.set_as(Stream, support::ulittle32_t(StreamNo), HashTraits);
123 }
124