[CodeView] Rename ModuleDebugFragment -> DebugSubsection.

This is more concise, and matches the terminology used in other
parts of the codebase more closely.

llvm-svn: 304218

1 files changed, 103 insertions, 0 deletions

diff --git a/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp
new file mode 100644
index 00000000000..9e19b4dab14
--- /dev/null
+++ b/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp
@@ -0,0 +1,103 @@
+//===- DebugChecksumsSubsection.cpp ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/CodeView/DebugChecksumsSubsection.h"
+
+#include "llvm/DebugInfo/CodeView/CodeViewError.h"
+#include "llvm/DebugInfo/CodeView/StringTable.h"
+#include "llvm/Support/BinaryStreamReader.h"
+
+using namespace llvm;
+using namespace llvm::codeview;
+
+struct FileChecksumEntryHeader {
+  using ulittle32_t = support::ulittle32_t;
+
+  ulittle32_t FileNameOffset; // Byte offset of filename in global string table.
+  uint8_t ChecksumSize;       // Number of bytes of checksum.
+  uint8_t ChecksumKind;       // FileChecksumKind
+                              // Checksum bytes follow.
+};
+
+Error llvm::VarStreamArrayExtractor<FileChecksumEntry>::extract(
+    BinaryStreamRef Stream, uint32_t &Len, FileChecksumEntry &Item) {
+  BinaryStreamReader Reader(Stream);
+
+  const FileChecksumEntryHeader *Header;
+  if (auto EC = Reader.readObject(Header))
+    return EC;
+
+  Item.FileNameOffset = Header->FileNameOffset;
+  Item.Kind = static_cast<FileChecksumKind>(Header->ChecksumKind);
+  if (auto EC = Reader.readBytes(Item.Checksum, Header->ChecksumSize))
+    return EC;
+
+  Len = alignTo(Header->ChecksumSize + sizeof(FileChecksumEntryHeader), 4);
+  return Error::success();
+}
+
+Error DebugChecksumsSubsectionRef::initialize(BinaryStreamReader Reader) {
+  if (auto EC = Reader.readArray(Checksums, Reader.bytesRemaining()))
+    return EC;
+
+  return Error::success();
+}
+
+DebugChecksumsSubsection::DebugChecksumsSubsection(StringTable &Strings)
+    : DebugSubsection(DebugSubsectionKind::FileChecksums), Strings(Strings) {}
+
+void DebugChecksumsSubsection::addChecksum(StringRef FileName,
+                                           FileChecksumKind Kind,
+                                           ArrayRef<uint8_t> Bytes) {
+  FileChecksumEntry Entry;
+  if (!Bytes.empty()) {
+    uint8_t *Copy = Storage.Allocate<uint8_t>(Bytes.size());
+    ::memcpy(Copy, Bytes.data(), Bytes.size());
+    Entry.Checksum = makeArrayRef(Copy, Bytes.size());
+  }
+
+  Entry.FileNameOffset = Strings.insert(FileName);
+  Entry.Kind = Kind;
+  Checksums.push_back(Entry);
+
+  // This maps the offset of this string in the string table to the offset
+  // of this checksum entry in the checksum buffer.
+  OffsetMap[Entry.FileNameOffset] = SerializedSize;
+  assert(SerializedSize % 4 == 0);
+
+  uint32_t Len = alignTo(sizeof(FileChecksumEntryHeader) + Bytes.size(), 4);
+  SerializedSize += Len;
+}
+
+uint32_t DebugChecksumsSubsection::calculateSerializedLength() {
+  return SerializedSize;
+}
+
+Error DebugChecksumsSubsection::commit(BinaryStreamWriter &Writer) {
+  for (const auto &FC : Checksums) {
+    FileChecksumEntryHeader Header;
+    Header.ChecksumKind = uint8_t(FC.Kind);
+    Header.ChecksumSize = FC.Checksum.size();
+    Header.FileNameOffset = FC.FileNameOffset;
+    if (auto EC = Writer.writeObject(Header))
+      return EC;
+    if (auto EC = Writer.writeArray(makeArrayRef(FC.Checksum)))
+      return EC;
+    if (auto EC = Writer.padToAlignment(4))
+      return EC;
+  }
+  return Error::success();
+}
+
+uint32_t DebugChecksumsSubsection::mapChecksumOffset(StringRef FileName) const {
+  uint32_t Offset = Strings.getStringId(FileName);
+  auto Iter = OffsetMap.find(Offset);
+  assert(Iter != OffsetMap.end());
+  return Iter->second;
+}