1/* $NetBSD: systmodes.S,v 1.4 2008/04/28 20:23:04 martin Exp $ */ 2 3/* This is a derivative work. */ 4 5/*- 6 * Copyright (c) 2001 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Ross Harvey. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34/* 35=============================================================================== 36 37This GNU assembler source file is part of TestFloat, Release 2a, a package 38of programs for testing the correctness of floating-point arithmetic 39complying to the IEC/IEEE Standard for Floating-Point. 40 41Written by John R. Hauser. More information is available through the Web 42page `http://HTTP.CS.Berkeley.EDU/~jhauser/arithmetic/TestFloat.html'. 43 44THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort 45has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT 46TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO 47PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY 48AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. 49 50Derivative works are acceptable, even for commercial purposes, so long as 51(1) they include prominent notice that the work is derivative, and (2) they 52include prominent notice akin to these four paragraphs for those parts of 53this code that are retained. 54 55=============================================================================== 56*/ 57 58 .text 59 60#include <machine/asm.h> 61 62/* 63------------------------------------------------------------------------------- 64Sets the rounding precision of subsequent extended double-precision 65operations. The `precision' argument should be one of 0, 32, 64, or 80. 66If `precision' is 32, the rounding precision is set equivalent to single 67precision; else if `precision' is 64, the rounding precision is set 68equivalent to double precision; else the rounding precision is set to full 69extended double precision. 70------------------------------------------------------------------------------- 71*/ 72 73ENTRY(syst_float_set_rounding_precision) 74 movb 4(%esp),%al 75 movb $0,%ah 76 cmpb $32,%al 77 je setRoundingPrecision 78 movb $2,%ah 79 cmpb $64,%al 80 je setRoundingPrecision 81 movb $3,%ah 82 cmpb $80,%al 83 je setRoundingPrecision 84 movb $0,%ah 85setRoundingPrecision: 86 movb $0,%al 87 subl $2,%esp 88 fnstcw 0(%esp) 89 andw $64767,0(%esp) 90 orw %ax,0(%esp) 91 fldcw 0(%esp) 92 addl $2,%esp 93 ret 94 95