usr/src/lib/libm/vax/infnan.s

/*
 * Copyright (c) 1985 Regents of the University of California.
 *
 * Use and reproduction of this software are granted  in  accordance  with
 * the terms and conditions specified in  the  Berkeley  Software  License
 * Agreement (in particular, this entails acknowledgement of the programs'
 * source, and inclusion of this notice) with the additional understanding
 * that  all  recipients  should regard themselves as participants  in  an
 * ongoing  research  project and hence should  feel  obligated  to report
 * their  experiences (good or bad) with these elementary function  codes,
 * using "sendbug 4bsd-bugs@BERKELEY", to the authors.
 *
 * @(#)infnan.s 1.1 (ELEFUNT) %G%
 *
 * infnan(arg) int arg;
 * where arg :=    EDOM if result is  NaN
 *           :=  ERANGE if result is +INF
 *           := -ERANGE if result is -INF
 *
 * The Reserved Operand Fault is generated inside of this routine.
 *
 */
        .globl  _infnan
        .set    EDOM,33
        .set    ERANGE,34
        .text
        .align 1
_infnan:
        .word   0x0
        cmpl    4(ap),$ERANGE
        bneq    1f
        movl    $ERANGE,_errno
        brb     2f
1:      movl    $EDOM,_errno
2:      emodd   $0,$0,$0x8000,r0,r0     # generates the reserved operand fault
        ret