1 //===- AppendingTypeTableBuilder.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/AppendingTypeTableBuilder.h"
10 #include "llvm/ADT/ArrayRef.h"
11 #include "llvm/DebugInfo/CodeView/CodeView.h"
12 #include "llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h"
13 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
14 #include "llvm/Support/Allocator.h"
15 #include "llvm/Support/ErrorHandling.h"
16 #include <cassert>
17 #include <cstdint>
18 #include <cstring>
19 
20 using namespace llvm;
21 using namespace llvm::codeview;
22 
nextTypeIndex() const23 TypeIndex AppendingTypeTableBuilder::nextTypeIndex() const {
24   return TypeIndex::fromArrayIndex(SeenRecords.size());
25 }
26 
AppendingTypeTableBuilder(BumpPtrAllocator & Storage)27 AppendingTypeTableBuilder::AppendingTypeTableBuilder(BumpPtrAllocator &Storage)
28     : RecordStorage(Storage) {}
29 
30 AppendingTypeTableBuilder::~AppendingTypeTableBuilder() = default;
31 
getFirst()32 std::optional<TypeIndex> AppendingTypeTableBuilder::getFirst() {
33   if (empty())
34     return std::nullopt;
35 
36   return TypeIndex(TypeIndex::FirstNonSimpleIndex);
37 }
38 
getNext(TypeIndex Prev)39 std::optional<TypeIndex> AppendingTypeTableBuilder::getNext(TypeIndex Prev) {
40   if (++Prev == nextTypeIndex())
41     return std::nullopt;
42   return Prev;
43 }
44 
getType(TypeIndex Index)45 CVType AppendingTypeTableBuilder::getType(TypeIndex Index){
46   return CVType(SeenRecords[Index.toArrayIndex()]);
47 }
48 
getTypeName(TypeIndex Index)49 StringRef AppendingTypeTableBuilder::getTypeName(TypeIndex Index) {
50   llvm_unreachable("Method not implemented");
51 }
52 
contains(TypeIndex Index)53 bool AppendingTypeTableBuilder::contains(TypeIndex Index) {
54   if (Index.isSimple() || Index.isNoneType())
55     return false;
56 
57   return Index.toArrayIndex() < SeenRecords.size();
58 }
59 
size()60 uint32_t AppendingTypeTableBuilder::size() { return SeenRecords.size(); }
61 
capacity()62 uint32_t AppendingTypeTableBuilder::capacity() { return SeenRecords.size(); }
63 
records() const64 ArrayRef<ArrayRef<uint8_t>> AppendingTypeTableBuilder::records() const {
65   return SeenRecords;
66 }
67 
reset()68 void AppendingTypeTableBuilder::reset() { SeenRecords.clear(); }
69 
stabilize(BumpPtrAllocator & RecordStorage,ArrayRef<uint8_t> Record)70 static ArrayRef<uint8_t> stabilize(BumpPtrAllocator &RecordStorage,
71                                    ArrayRef<uint8_t> Record) {
72   uint8_t *Stable = RecordStorage.Allocate<uint8_t>(Record.size());
73   memcpy(Stable, Record.data(), Record.size());
74   return ArrayRef<uint8_t>(Stable, Record.size());
75 }
76 
77 TypeIndex
insertRecordBytes(ArrayRef<uint8_t> & Record)78 AppendingTypeTableBuilder::insertRecordBytes(ArrayRef<uint8_t> &Record) {
79   TypeIndex NewTI = nextTypeIndex();
80   Record = stabilize(RecordStorage, Record);
81   SeenRecords.push_back(Record);
82   return NewTI;
83 }
84 
85 TypeIndex
insertRecord(ContinuationRecordBuilder & Builder)86 AppendingTypeTableBuilder::insertRecord(ContinuationRecordBuilder &Builder) {
87   TypeIndex TI;
88   auto Fragments = Builder.end(nextTypeIndex());
89   assert(!Fragments.empty());
90   for (auto C : Fragments)
91     TI = insertRecordBytes(C.RecordData);
92   return TI;
93 }
94 
replaceType(TypeIndex & Index,CVType Data,bool Stabilize)95 bool AppendingTypeTableBuilder::replaceType(TypeIndex &Index, CVType Data,
96                                             bool Stabilize) {
97   assert(Index.toArrayIndex() < SeenRecords.size() &&
98          "This function cannot be used to insert records!");
99 
100   ArrayRef<uint8_t> Record = Data.data();
101   if (Stabilize)
102     Record = stabilize(RecordStorage, Record);
103   SeenRecords[Index.toArrayIndex()] = Record;
104   return true;
105 }
106