/*      $OpenBSD: fenv.S,v 1.2 2024/04/01 18:52:34 anton Exp $  */
/*
 * Copyright (c) 2018 Alexander Bluhm <bluhm@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/syscall.h>

#define PINSYSCALL(sysno, label)                                        \
        .pushsection .openbsd.syscalls,"",%progbits;                    \
        .p2align 2;                                                     \
        .long label;                                                    \
        .long sysno;                                                    \
        .popsection;

        .section        .note.openbsd.ident, "a"
        .p2align        2
        .long           8
        .long           4
        .long           1
        .ascii          "OpenBSD\0"
        .long           0
        .previous

        .data
env:
        .long   1       /* __control */
        .long   1       /* __status */
        .long   1       /* __tag */
        .long   1       /* __others 0 */
        .long   1       /* __others 1 */
        .long   1       /* __others 2 */
        .long   1       /* __others 3 */
mxcsr:
        .long   1       /* __mxcsr */
env_end:

        .text
        .align  8
        .global _start
_start:
        fnstenv env
        stmxcsr mxcsr
        mov     $SYS_write,     %rax
        mov     $1,             %rdi
        mov     $env,           %rsi
        mov     $(env_end-env), %rdx
1:
        syscall
        PINSYSCALL(SYS_write, 1b)
        mov     $SYS_exit,      %rax
        mov     $0,             %rdi
2:
        syscall
        PINSYSCALL(SYS_exit, 2b)