Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Copyright 2011 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 *
14 * Provide a mask based on the pointer alignment that
15 * sets up non-zero bytes before the beginning of the string.
16 * The MASK expression works because shift counts are taken mod 64.
17 * Also, specify how to count "first" and "last" bits
18 * when the bits have been read as a word.
19 */
20
21#include <asm/byteorder.h>
22
23#ifdef __LITTLE_ENDIAN
24#define MASK(x) (__insn_shl(1ULL, (x << 3)) - 1)
25#define NULMASK(x) ((2ULL << x) - 1)
26#define CFZ(x) __insn_ctz(x)
27#define REVCZ(x) __insn_clz(x)
28#else
29#define MASK(x) (__insn_shl(-2LL, ((-x << 3) - 1)))
30#define NULMASK(x) (-2LL << (63 - x))
31#define CFZ(x) __insn_clz(x)
32#define REVCZ(x) __insn_ctz(x)
33#endif