44 lines · cpp
1//===- LEB128.cpp - LEB128 utility functions implementation -----*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements some utility functions for encoding SLEB128 and10// ULEB128 values.11//12//===----------------------------------------------------------------------===//13 14#include "llvm/Support/LEB128.h"15 16namespace llvm {17 18/// Utility function to get the size of the ULEB128-encoded value.19unsigned getULEB128Size(uint64_t Value) {20 unsigned Size = 0;21 do {22 Value >>= 7;23 Size += sizeof(int8_t);24 } while (Value);25 return Size;26}27 28/// Utility function to get the size of the SLEB128-encoded value.29unsigned getSLEB128Size(int64_t Value) {30 unsigned Size = 0;31 int Sign = Value >> (8 * sizeof(Value) - 1);32 bool IsMore;33 34 do {35 unsigned Byte = Value & 0x7f;36 Value >>= 7;37 IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;38 Size += sizeof(int8_t);39 } while (IsMore);40 return Size;41}42 43} // namespace llvm44