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 */