C++程序  |  41行  |  1.08 KB

//===- 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.
//
//===----------------------------------------------------------------------===//

/* Capstone Disassembly Engine */
/* By Nguyen Anh Quynh <aquynh@gmail.com>, 2013-2014 */

#ifndef CS_LLVM_SUPPORT_LEB128_H
#define CS_LLVM_SUPPORT_LEB128_H

#if !defined(_MSC_VER) || !defined(_KERNEL_MODE)
#include <stdint.h>
#endif

/// Utility function to decode a ULEB128 value.
static inline uint64_t decodeULEB128(const uint8_t *p, unsigned *n)
{
	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;
}

#endif  // LLVM_SYSTEM_LEB128_H