sysdeps/sh/string-fzb.h

   1 /* Zero byte detection; boolean.  SH4 version.
   2    Copyright (C) 2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef STRING_FZB_H
  20 #define STRING_FZB_H 1
  21
  22 #include <sys/cdefs.h>
  23 #include <string-optype.h>
  24
  25 /* Determine if any bytes within X1 and X2 are equal.  */
  26 static __always_inline _Bool
  27 has_eq (op_t x1, op_t x2)
  28 {
  29   int ret;
  30
  31   /* TODO: A compiler builtin for cmp/str would be much better.  It is
  32      difficult to use asm goto here, because the range of bt/bf are
  33      quite small.  */
  34   asm("cmp/str %1,%2\n\t"
  35       "movt %0"
  36       : "=r" (ret) : "r" (x1), "r" (x2) : "t");
  37
  38   return ret;
  39 }
  40
  41 /* Determine if any byte within X is zero.  */
  42 static __always_inline _Bool
  43 has_zero (op_t x)
  44 {
  45   return has_eq (x, 0);
  46 }
  47
  48 /* Likewise, but for zeros in X1 and equal bytes between X1 and X2.  */
  49 static __always_inline _Bool
  50 has_zero_eq (op_t x1, op_t x2)
  51 {
  52   return has_zero (x1) | has_eq (x1, x2);
  53 }
  54
  55 #endif /* STRING_FZB_H */