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//===- LEB128.cpp - LEB128 utility functions implementation -----*- C++ -*-===// 
// 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
// See https://llvm.org/LICENSE.txt for license information. 
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
// 
//===----------------------------------------------------------------------===// 
// 
// This file implements some utility functions for encoding SLEB128 and 
// ULEB128 values. 
// 
//===----------------------------------------------------------------------===// 
 
#include "llvm/Support/LEB128.h" 
 
namespace llvm { 
 
/// Utility function to get the size of the ULEB128-encoded value. 
unsigned getULEB128Size(uint64_t Value) { 
  unsigned Size = 0; 
  do { 
    Value >>= 7; 
    Size += sizeof(int8_t); 
  } while (Value); 
  return Size; 
} 
 
/// Utility function to get the size of the SLEB128-encoded value. 
unsigned getSLEB128Size(int64_t Value) { 
  unsigned Size = 0; 
  int Sign = Value >> (8 * sizeof(Value) - 1); 
  bool IsMore; 
 
  do { 
    unsigned Byte = Value & 0x7f; 
    Value >>= 7; 
    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0; 
    Size += sizeof(int8_t); 
  } while (IsMore); 
  return Size; 
} 
 
}  // namespace llvm