diff options
Diffstat (limited to 'clang-r353983/include/llvm/Support/JamCRC.h')
| -rw-r--r-- | clang-r353983/include/llvm/Support/JamCRC.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/clang-r353983/include/llvm/Support/JamCRC.h b/clang-r353983/include/llvm/Support/JamCRC.h new file mode 100644 index 00000000..b6fc4e7b --- /dev/null +++ b/clang-r353983/include/llvm/Support/JamCRC.h @@ -0,0 +1,48 @@ +//===-- llvm/Support/JamCRC.h - Cyclic Redundancy Check ---------*- 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 contains an implementation of JamCRC. +// +// We will use the "Rocksoft^tm Model CRC Algorithm" to describe the properties +// of this CRC: +// Width : 32 +// Poly : 04C11DB7 +// Init : FFFFFFFF +// RefIn : True +// RefOut : True +// XorOut : 00000000 +// Check : 340BC6D9 (result of CRC for "123456789") +// +// N.B. We permit flexibility of the "Init" value. Some consumers of this need +// it to be zero. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_SUPPORT_JAMCRC_H +#define LLVM_SUPPORT_JAMCRC_H + +#include "llvm/Support/DataTypes.h" + +namespace llvm { +template <typename T> class ArrayRef; + +class JamCRC { +public: + JamCRC(uint32_t Init = 0xFFFFFFFFU) : CRC(Init) {} + + // Update the CRC calculation with Data. + void update(ArrayRef<char> Data); + + uint32_t getCRC() const { return CRC; } + +private: + uint32_t CRC; +}; +} // End of namespace llvm + +#endif |
