1 //===- GlobalTypeTableBuilder.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 #include "llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h"
10 #include "llvm/ADT/ArrayRef.h"
11 #include "llvm/ADT/None.h"
12 #include "llvm/DebugInfo/CodeView/CodeView.h"
13 #include "llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h"
14 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
15 #include "llvm/Support/Allocator.h"
16 #include "llvm/Support/ErrorHandling.h"
17 #include <cassert>
18 #include <cstdint>
19 #include <cstring>
20
21 using namespace llvm;
22 using namespace llvm::codeview;
23
nextTypeIndex() const24 TypeIndex GlobalTypeTableBuilder::nextTypeIndex() const {
25 return TypeIndex::fromArrayIndex(SeenRecords.size());
26 }
27
GlobalTypeTableBuilder(BumpPtrAllocator & Storage)28 GlobalTypeTableBuilder::GlobalTypeTableBuilder(BumpPtrAllocator &Storage)
29 : RecordStorage(Storage) {
30 SeenRecords.reserve(4096);
31 }
32
33 GlobalTypeTableBuilder::~GlobalTypeTableBuilder() = default;
34
getFirst()35 Optional<TypeIndex> GlobalTypeTableBuilder::getFirst() {
36 if (empty())
37 return None;
38
39 return TypeIndex(TypeIndex::FirstNonSimpleIndex);
40 }
41
getNext(TypeIndex Prev)42 Optional<TypeIndex> GlobalTypeTableBuilder::getNext(TypeIndex Prev) {
43 if (++Prev == nextTypeIndex())
44 return None;
45 return Prev;
46 }
47
getType(TypeIndex Index)48 CVType GlobalTypeTableBuilder::getType(TypeIndex Index) {
49 CVType Type(SeenRecords[Index.toArrayIndex()]);
50 return Type;
51 }
52
getTypeName(TypeIndex Index)53 StringRef GlobalTypeTableBuilder::getTypeName(TypeIndex Index) {
54 llvm_unreachable("Method not implemented");
55 }
56
contains(TypeIndex Index)57 bool GlobalTypeTableBuilder::contains(TypeIndex Index) {
58 if (Index.isSimple() || Index.isNoneType())
59 return false;
60
61 return Index.toArrayIndex() < SeenRecords.size();
62 }
63
size()64 uint32_t GlobalTypeTableBuilder::size() { return SeenRecords.size(); }
65
capacity()66 uint32_t GlobalTypeTableBuilder::capacity() { return SeenRecords.size(); }
67
records() const68 ArrayRef<ArrayRef<uint8_t>> GlobalTypeTableBuilder::records() const {
69 return SeenRecords;
70 }
71
hashes() const72 ArrayRef<GloballyHashedType> GlobalTypeTableBuilder::hashes() const {
73 return SeenHashes;
74 }
75
reset()76 void GlobalTypeTableBuilder::reset() {
77 HashedRecords.clear();
78 SeenRecords.clear();
79 }
80
stabilize(BumpPtrAllocator & Alloc,ArrayRef<uint8_t> Data)81 static inline ArrayRef<uint8_t> stabilize(BumpPtrAllocator &Alloc,
82 ArrayRef<uint8_t> Data) {
83 uint8_t *Stable = Alloc.Allocate<uint8_t>(Data.size());
84 memcpy(Stable, Data.data(), Data.size());
85 return makeArrayRef(Stable, Data.size());
86 }
87
insertRecordBytes(ArrayRef<uint8_t> Record)88 TypeIndex GlobalTypeTableBuilder::insertRecordBytes(ArrayRef<uint8_t> Record) {
89 GloballyHashedType GHT =
90 GloballyHashedType::hashType(Record, SeenHashes, SeenHashes);
91 return insertRecordAs(GHT, Record.size(),
92 [Record](MutableArrayRef<uint8_t> Data) {
93 assert(Data.size() == Record.size());
94 ::memcpy(Data.data(), Record.data(), Record.size());
95 return Data;
96 });
97 }
98
99 TypeIndex
insertRecord(ContinuationRecordBuilder & Builder)100 GlobalTypeTableBuilder::insertRecord(ContinuationRecordBuilder &Builder) {
101 TypeIndex TI;
102 auto Fragments = Builder.end(nextTypeIndex());
103 assert(!Fragments.empty());
104 for (auto C : Fragments)
105 TI = insertRecordBytes(C.RecordData);
106 return TI;
107 }
108
replaceType(TypeIndex & Index,CVType Data,bool Stabilize)109 bool GlobalTypeTableBuilder::replaceType(TypeIndex &Index, CVType Data,
110 bool Stabilize) {
111 assert(Index.toArrayIndex() < SeenRecords.size() &&
112 "This function cannot be used to insert records!");
113
114 ArrayRef<uint8_t> Record = Data.data();
115 assert(Record.size() < UINT32_MAX && "Record too big");
116 assert(Record.size() % 4 == 0 &&
117 "The type record size is not a multiple of 4 bytes which will cause "
118 "misalignment in the output TPI stream!");
119
120 GloballyHashedType Hash =
121 GloballyHashedType::hashType(Record, SeenHashes, SeenHashes);
122 auto Result = HashedRecords.try_emplace(Hash, Index.toArrayIndex());
123 if (!Result.second) {
124 Index = Result.first->second;
125 return false; // The record is already there, at a different location
126 }
127
128 if (Stabilize)
129 Record = stabilize(RecordStorage, Record);
130
131 SeenRecords[Index.toArrayIndex()] = Record;
132 SeenHashes[Index.toArrayIndex()] = Hash;
133 return true;
134 }
135