glibc/sysdeps/alpha/string-fza.h

61 lines
1.8 KiB
C

/* Basic zero byte detection. Generic C version.
Copyright (C) 2023-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _STRING_FZA_H
#define _STRING_FZA_H 1
#include <string-misc.h>
#include <string-optype.h>
/* The CMPBGE instruction creates a bit mask rather than a byte mask.
However, if we narrow find_t to either 'int' or 'uint8_t', we get
unnecessary truncation instructions from the 'unsigned long' type
returned by __builtin_alpha_cmpbge. */
typedef op_t find_t;
static __always_inline find_t
find_zero_all (op_t x)
{
return __builtin_alpha_cmpbge (0, x);
}
static __always_inline find_t
find_eq_all (op_t x1, op_t x2)
{
return find_zero_all (x1 ^ x2);
}
static __always_inline find_t
find_zero_eq_all (op_t x1, op_t x2)
{
return find_zero_all (x1) | find_zero_all (x1 ^ x2);
}
static __always_inline find_t
find_zero_ne_all (op_t x1, op_t x2)
{
return find_zero_all (x1) | (find_zero_all (x1 ^ x2) ^ 0xff);
}
/* Define the "inexact" versions in terms of the exact versions. */
#define find_zero_low find_zero_all
#define find_eq_low find_eq_all
#define find_zero_eq_low find_zero_eq_all
#endif /* _STRING_FZA_H */