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/* Zero byte detection, boolean. HPPA 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_FZB_H
#define _STRING_FZB_H 1
#include <sys/cdefs.h>
#include <string-optype.h>
_Static_assert (sizeof (op_t) == 4, "64-bit not supported");
/* Determine if any byte within X is zero. This is a pure boolean test. */
static __always_inline _Bool
has_zero (op_t x)
{
/* It's more useful to expose a control transfer to the compiler
than to expose a proper boolean result. */
asm goto ("uxor,sbz %%r0,%0,%%r0\n\t"
"b,n %l1" : : "r"(x) : : nbz);
return 1;
nbz:
return 0;
}
/* Likewise, but for byte equality between X1 and X2. */
static __always_inline _Bool
has_eq (op_t x1, op_t x2)
{
asm goto ("uxor,sbz %0,%1,%%r0\n\t"
"b,n %l2" : : "r"(x1), "r"(x2) : : nbz);
return 1;
nbz:
return 0;
}
/* Likewise, but for zeros in X1 and equal bytes between X1 and X2. */
static __always_inline _Bool
has_zero_eq (op_t x1, op_t x2)
{
asm goto ("uxor,sbz %%r0,%0,%%r0\n\t"
"uxor,nbz %0,%1,%%r0\n\t"
"b,n %l2" : : "r"(x1), "r"(x2) : : sbz);
return 0;
sbz:
return 1;
}
#endif /* _STRING_FZB_H */
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