/* Macros to swap the order of bytes in 16-bit integer values. s390 version Copyright (C) 2012 Free Software Foundation, Inc. Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). 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 . */ #ifndef _BITS_BYTESWAP_H # error "Never use directly; include instead." #endif #include /* Swap bytes in 16 bit value. */ #if defined __GNUC__ && __GNUC__ >= 2 # if __WORDSIZE == 64 # define __bswap_16(x) \ (__extension__ \ ({ unsigned short int __v, __x = (unsigned short int) (x); \ if (__builtin_constant_p (x)) \ __v = __bswap_constant_16 (__x); \ else { \ unsigned short int __tmp = (unsigned short int) (__x); \ __asm__ __volatile__ ( \ "lrvh %0,%1" \ : "=&d" (__v) : "m" (__tmp) ); \ } \ __v; })) # else # define __bswap_16(x) \ (__extension__ \ ({ unsigned short int __v, __x = (unsigned short int) (x); \ if (__builtin_constant_p (x)) \ __v = __bswap_constant_16 (__x); \ else { \ unsigned short int __tmp = (unsigned short int) (__x); \ __asm__ __volatile__ ( \ "sr %0,%0\n" \ "la 1,%1\n" \ "icm %0,2,1(1)\n" \ "ic %0,0(1)" \ : "=&d" (__v) : "m" (__tmp) : "1"); \ } \ __v; })) # endif #else /* This is better than nothing. */ static __inline unsigned short int __bswap_16 (unsigned short int __bsx) { return __bswap_constant_16 (__bsx); } #endif