1 //===- DebugSubsectionRecord.cpp ------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/DebugInfo/CodeView/DebugSubsectionRecord.h"
11 #include "llvm/DebugInfo/CodeView/CodeView.h"
12 #include "llvm/DebugInfo/CodeView/DebugSubsection.h"
13 #include "llvm/Support/BinaryStreamReader.h"
14 #include "llvm/Support/BinaryStreamWriter.h"
15 #include "llvm/Support/Error.h"
16 #include "llvm/Support/MathExtras.h"
17 #include <algorithm>
18 #include <cassert>
19 #include <cstdint>
20
21 using namespace llvm;
22 using namespace llvm::codeview;
23
24 DebugSubsectionRecord::DebugSubsectionRecord() = default;
25
DebugSubsectionRecord(DebugSubsectionKind Kind,BinaryStreamRef Data,CodeViewContainer Container)26 DebugSubsectionRecord::DebugSubsectionRecord(DebugSubsectionKind Kind,
27 BinaryStreamRef Data,
28 CodeViewContainer Container)
29 : Container(Container), Kind(Kind), Data(Data) {}
30
initialize(BinaryStreamRef Stream,DebugSubsectionRecord & Info,CodeViewContainer Container)31 Error DebugSubsectionRecord::initialize(BinaryStreamRef Stream,
32 DebugSubsectionRecord &Info,
33 CodeViewContainer Container) {
34 const DebugSubsectionHeader *Header;
35 BinaryStreamReader Reader(Stream);
36 if (auto EC = Reader.readObject(Header))
37 return EC;
38
39 DebugSubsectionKind Kind =
40 static_cast<DebugSubsectionKind>(uint32_t(Header->Kind));
41 if (auto EC = Reader.readStreamRef(Info.Data, Header->Length))
42 return EC;
43 Info.Container = Container;
44 Info.Kind = Kind;
45 return Error::success();
46 }
47
getRecordLength() const48 uint32_t DebugSubsectionRecord::getRecordLength() const {
49 return sizeof(DebugSubsectionHeader) + Data.getLength();
50 }
51
kind() const52 DebugSubsectionKind DebugSubsectionRecord::kind() const { return Kind; }
53
getRecordData() const54 BinaryStreamRef DebugSubsectionRecord::getRecordData() const { return Data; }
55
DebugSubsectionRecordBuilder(std::shared_ptr<DebugSubsection> Subsection,CodeViewContainer Container)56 DebugSubsectionRecordBuilder::DebugSubsectionRecordBuilder(
57 std::shared_ptr<DebugSubsection> Subsection, CodeViewContainer Container)
58 : Subsection(std::move(Subsection)), Container(Container) {}
59
DebugSubsectionRecordBuilder(const DebugSubsectionRecord & Contents,CodeViewContainer Container)60 DebugSubsectionRecordBuilder::DebugSubsectionRecordBuilder(
61 const DebugSubsectionRecord &Contents, CodeViewContainer Container)
62 : Contents(Contents), Container(Container) {}
63
calculateSerializedLength()64 uint32_t DebugSubsectionRecordBuilder::calculateSerializedLength() {
65 uint32_t DataSize = Subsection ? Subsection->calculateSerializedSize()
66 : Contents.getRecordData().getLength();
67 // The length of the entire subsection is always padded to 4 bytes,
68 // regardless of the container kind.
69 return sizeof(DebugSubsectionHeader) + alignTo(DataSize, 4);
70 }
71
commit(BinaryStreamWriter & Writer) const72 Error DebugSubsectionRecordBuilder::commit(BinaryStreamWriter &Writer) const {
73 assert(Writer.getOffset() % alignOf(Container) == 0 &&
74 "Debug Subsection not properly aligned");
75
76 DebugSubsectionHeader Header;
77 Header.Kind = uint32_t(Subsection ? Subsection->kind() : Contents.kind());
78 // The value written into the Header's Length field is only padded to the
79 // container's alignment
80 uint32_t DataSize = Subsection ? Subsection->calculateSerializedSize()
81 : Contents.getRecordData().getLength();
82 Header.Length = alignTo(DataSize, alignOf(Container));
83
84 if (auto EC = Writer.writeObject(Header))
85 return EC;
86 if (Subsection) {
87 if (auto EC = Subsection->commit(Writer))
88 return EC;
89 } else {
90 if (auto EC = Writer.writeStreamRef(Contents.getRecordData()))
91 return EC;
92 }
93 if (auto EC = Writer.padToAlignment(4))
94 return EC;
95
96 return Error::success();
97 }
98