glibc/sysdeps/i386/htons.S

/* Change byte order in word.  For Intel 80x86, x >= 3.
   Copyright (C) 1997-2019 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
   <https://www.gnu.org/licenses/>.  */

#include <sysdep.h>
#include "asm-syntax.h"

/*
   INPUT PARAMETERS:
   word		(sp + 4)
*/

	.text
ENTRY (htons)
	movl	4(%esp), %eax
	andl	$0xffff, %eax
	rorw	$8, %ax
	ret
END (htons)

weak_alias (htons, ntohs)