Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/DebugInfo/CodeView/DebugLinesSubsection.h b/linux-x64/clang/include/llvm/DebugInfo/CodeView/DebugLinesSubsection.h
new file mode 100644
index 0000000..53044b6
--- /dev/null
+++ b/linux-x64/clang/include/llvm/DebugInfo/CodeView/DebugLinesSubsection.h
@@ -0,0 +1,150 @@
+//===- DebugLinesSubsection.h -----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_CODEVIEW_DEBUGLINESSUBSECTION_H
+#define LLVM_DEBUGINFO_CODEVIEW_DEBUGLINESSUBSECTION_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/DebugInfo/CodeView/CodeView.h"
+#include "llvm/DebugInfo/CodeView/DebugSubsection.h"
+#include "llvm/DebugInfo/CodeView/Line.h"
+#include "llvm/Support/BinaryStreamArray.h"
+#include "llvm/Support/BinaryStreamReader.h"
+#include "llvm/Support/BinaryStreamRef.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/Error.h"
+#include <cstdint>
+#include <vector>
+
+namespace llvm {
+namespace codeview {
+
+class DebugChecksumsSubsection;
+class DebugStringTableSubsection;
+
+// Corresponds to the `CV_DebugSLinesHeader_t` structure.
+struct LineFragmentHeader {
+  support::ulittle32_t RelocOffset;  // Code offset of line contribution.
+  support::ulittle16_t RelocSegment; // Code segment of line contribution.
+  support::ulittle16_t Flags;        // See LineFlags enumeration.
+  support::ulittle32_t CodeSize;     // Code size of this line contribution.
+};
+
+// Corresponds to the `CV_DebugSLinesFileBlockHeader_t` structure.
+struct LineBlockFragmentHeader {
+  support::ulittle32_t NameIndex; // Offset of FileChecksum entry in File
+                                  // checksums buffer.  The checksum entry then
+                                  // contains another offset into the string
+                                  // table of the actual name.
+  support::ulittle32_t NumLines;  // Number of lines
+  support::ulittle32_t BlockSize; // Code size of block, in bytes.
+  // The following two variable length arrays appear immediately after the
+  // header.  The structure definitions follow.
+  // LineNumberEntry   Lines[NumLines];
+  // ColumnNumberEntry Columns[NumLines];
+};
+
+// Corresponds to `CV_Line_t` structure
+struct LineNumberEntry {
+  support::ulittle32_t Offset; // Offset to start of code bytes for line number
+  support::ulittle32_t Flags;  // Start:24, End:7, IsStatement:1
+};
+
+// Corresponds to `CV_Column_t` structure
+struct ColumnNumberEntry {
+  support::ulittle16_t StartColumn;
+  support::ulittle16_t EndColumn;
+};
+
+struct LineColumnEntry {
+  support::ulittle32_t NameIndex;
+  FixedStreamArray<LineNumberEntry> LineNumbers;
+  FixedStreamArray<ColumnNumberEntry> Columns;
+};
+
+class LineColumnExtractor {
+public:
+  Error operator()(BinaryStreamRef Stream, uint32_t &Len,
+                   LineColumnEntry &Item);
+
+  const LineFragmentHeader *Header = nullptr;
+};
+
+class DebugLinesSubsectionRef final : public DebugSubsectionRef {
+  friend class LineColumnExtractor;
+
+  using LineInfoArray = VarStreamArray<LineColumnEntry, LineColumnExtractor>;
+  using Iterator = LineInfoArray::Iterator;
+
+public:
+  DebugLinesSubsectionRef();
+
+  static bool classof(const DebugSubsectionRef *S) {
+    return S->kind() == DebugSubsectionKind::Lines;
+  }
+
+  Error initialize(BinaryStreamReader Reader);
+
+  Iterator begin() const { return LinesAndColumns.begin(); }
+  Iterator end() const { return LinesAndColumns.end(); }
+
+  const LineFragmentHeader *header() const { return Header; }
+
+  bool hasColumnInfo() const;
+
+private:
+  const LineFragmentHeader *Header = nullptr;
+  LineInfoArray LinesAndColumns;
+};
+
+class DebugLinesSubsection final : public DebugSubsection {
+  struct Block {
+    Block(uint32_t ChecksumBufferOffset)
+        : ChecksumBufferOffset(ChecksumBufferOffset) {}
+
+    uint32_t ChecksumBufferOffset;
+    std::vector<LineNumberEntry> Lines;
+    std::vector<ColumnNumberEntry> Columns;
+  };
+
+public:
+  DebugLinesSubsection(DebugChecksumsSubsection &Checksums,
+                       DebugStringTableSubsection &Strings);
+
+  static bool classof(const DebugSubsection *S) {
+    return S->kind() == DebugSubsectionKind::Lines;
+  }
+
+  void createBlock(StringRef FileName);
+  void addLineInfo(uint32_t Offset, const LineInfo &Line);
+  void addLineAndColumnInfo(uint32_t Offset, const LineInfo &Line,
+                            uint32_t ColStart, uint32_t ColEnd);
+
+  uint32_t calculateSerializedSize() const override;
+  Error commit(BinaryStreamWriter &Writer) const override;
+
+  void setRelocationAddress(uint16_t Segment, uint32_t Offset);
+  void setCodeSize(uint32_t Size);
+  void setFlags(LineFlags Flags);
+
+  bool hasColumnInfo() const;
+
+private:
+  DebugChecksumsSubsection &Checksums;
+  uint32_t RelocOffset = 0;
+  uint16_t RelocSegment = 0;
+  uint32_t CodeSize = 0;
+  LineFlags Flags = LF_None;
+  std::vector<Block> Blocks;
+};
+
+} // end namespace codeview
+} // end namespace llvm
+
+#endif // LLVM_DEBUGINFO_CODEVIEW_DEBUGLINESSUBSECTION_H