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//===- LEB128.cpp - LEB128 utility functions implementation -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// 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
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