Imported Upstream version 5.18.0.161

Former-commit-id: 4db48158d3a35497b8f118ab21b5f08ac3d86d98

external/llvm/lib/DebugInfo/CodeView/DebugSubsectionRecord.cpp

@@ -0,0 +1,97 @@
+//===- DebugSubsectionRecord.cpp ------------------------------------------===//
+//
+//                     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/DebugSubsectionRecord.h"
+#include "llvm/DebugInfo/CodeView/CodeView.h"
+#include "llvm/DebugInfo/CodeView/DebugSubsection.h"
+#include "llvm/Support/BinaryStreamReader.h"
+#include "llvm/Support/BinaryStreamWriter.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/MathExtras.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+using namespace llvm::codeview;
+
+DebugSubsectionRecord::DebugSubsectionRecord() = default;
+
+DebugSubsectionRecord::DebugSubsectionRecord(DebugSubsectionKind Kind,
+                                             BinaryStreamRef Data,
+                                             CodeViewContainer Container)
+    : Container(Container), Kind(Kind), Data(Data) {}
+
+Error DebugSubsectionRecord::initialize(BinaryStreamRef Stream,
+                                        DebugSubsectionRecord &Info,
+                                        CodeViewContainer Container) {
+  const DebugSubsectionHeader *Header;
+  BinaryStreamReader Reader(Stream);
+  if (auto EC = Reader.readObject(Header))
+    return EC;
+
+  DebugSubsectionKind Kind =
+      static_cast<DebugSubsectionKind>(uint32_t(Header->Kind));
+  if (auto EC = Reader.readStreamRef(Info.Data, Header->Length))
+    return EC;
+  Info.Container = Container;
+  Info.Kind = Kind;
+  return Error::success();
+}
+
+uint32_t DebugSubsectionRecord::getRecordLength() const {
+  return sizeof(DebugSubsectionHeader) + Data.getLength();
+}
+
+DebugSubsectionKind DebugSubsectionRecord::kind() const { return Kind; }
+
+BinaryStreamRef DebugSubsectionRecord::getRecordData() const { return Data; }
+
+DebugSubsectionRecordBuilder::DebugSubsectionRecordBuilder(
+    std::shared_ptr<DebugSubsection> Subsection, CodeViewContainer Container)
+    : Subsection(std::move(Subsection)), Container(Container) {}
+
+DebugSubsectionRecordBuilder::DebugSubsectionRecordBuilder(
+    const DebugSubsectionRecord &Contents, CodeViewContainer Container)
+    : Contents(Contents), Container(Container) {}
+
+uint32_t DebugSubsectionRecordBuilder::calculateSerializedLength() {
+  uint32_t DataSize = Subsection ? Subsection->calculateSerializedSize()
+                                 : Contents.getRecordData().getLength();
+  // The length of the entire subsection is always padded to 4 bytes,
+  // regardless of the container kind.
+  return sizeof(DebugSubsectionHeader) + alignTo(DataSize, 4);
+}
+
+Error DebugSubsectionRecordBuilder::commit(BinaryStreamWriter &Writer) const {
+  assert(Writer.getOffset() % alignOf(Container) == 0 &&
+         "Debug Subsection not properly aligned");
+
+  DebugSubsectionHeader Header;
+  Header.Kind = uint32_t(Subsection ? Subsection->kind() : Contents.kind());
+  // The value written into the Header's Length field is only padded to the
+  // container's alignment
+  uint32_t DataSize = Subsection ? Subsection->calculateSerializedSize()
+                                 : Contents.getRecordData().getLength();
+  Header.Length = alignTo(DataSize, alignOf(Container));
+
+  if (auto EC = Writer.writeObject(Header))
+    return EC;
+  if (Subsection) {
+    if (auto EC = Subsection->commit(Writer))
+      return EC;
+  } else {
+    if (auto EC = Writer.writeStreamRef(Contents.getRecordData()))
+      return EC;
+  }
+  if (auto EC = Writer.padToAlignment(4))
+    return EC;
+
+  return Error::success();
+}