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diff --git a/include/llvm/Support/LEB128.h b/include/llvm/Support/LEB128.h
new file mode 100644
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+++ b/include/llvm/Support/LEB128.h
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+//===- llvm/Support/LEB128.h - [SU]LEB128 utility functions -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares some utility functions for encoding SLEB128 and
+// ULEB128 values.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SYSTEM_LEB128_H
+#define LLVM_SYSTEM_LEB128_H
+
+#include <llvm/Support/raw_ostream.h>
+
+namespace llvm {
+
+/// Utility function to encode a SLEB128 value to an output stream.
+static inline void encodeSLEB128(int64_t Value, raw_ostream &OS) {
+  bool More;
+  do {
+    uint8_t Byte = Value & 0x7f;
+    // NOTE: this assumes that this signed shift is an arithmetic right shift.
+    Value >>= 7;
+    More = !((((Value == 0 ) && ((Byte & 0x40) == 0)) ||
+              ((Value == -1) && ((Byte & 0x40) != 0))));
+    if (More)
+      Byte |= 0x80; // Mark this byte that that more bytes will follow.
+    OS << char(Byte);
+  } while (More);
+}
+
+/// Utility function to encode a ULEB128 value to an output stream.
+static inline void encodeULEB128(uint64_t Value, raw_ostream &OS,
+                                 unsigned Padding = 0) {
+  do {
+    uint8_t Byte = Value & 0x7f;
+    Value >>= 7;
+    if (Value != 0 || Padding != 0)
+      Byte |= 0x80; // Mark this byte that that more bytes will follow.
+    OS << char(Byte);
+  } while (Value != 0);
+
+  // Pad with 0x80 and emit a null byte at the end.
+  if (Padding != 0) {
+    for (; Padding != 1; --Padding)
+      OS << '\x80';
+    OS << '\x00';
+  }
+}
+
+/// Utility function to encode a ULEB128 value to a buffer. Returns
+/// the length in bytes of the encoded value.
+static inline unsigned encodeULEB128(uint64_t Value, uint8_t *p,
+                                     unsigned Padding = 0) {
+  uint8_t *orig_p = p;
+  do {
+    uint8_t Byte = Value & 0x7f;
+    Value >>= 7;
+    if (Value != 0 || Padding != 0)
+      Byte |= 0x80; // Mark this byte that that more bytes will follow.
+    *p++ = Byte;
+  } while (Value != 0);
+
+  // Pad with 0x80 and emit a null byte at the end.
+  if (Padding != 0) {
+    for (; Padding != 1; --Padding)
+      *p++ = '\x80';
+    *p++ = '\x00';
+  }
+  return (unsigned)(p - orig_p);
+}
+
+
+/// Utility function to decode a ULEB128 value.
+static inline uint64_t decodeULEB128(const uint8_t *p, unsigned *n = 0) {
+  const uint8_t *orig_p = p;
+  uint64_t Value = 0;
+  unsigned Shift = 0;
+  do {
+    Value += (*p & 0x7f) << Shift;
+    Shift += 7;
+  } while (*p++ >= 128);
+  if (n)
+    *n = (unsigned)(p - orig_p);
+  return Value;
+}
+
+}  // namespace llvm
+
+#endif  // LLVM_SYSTEM_LEB128_H