/*- * Copyright (c) 2011 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Matt Thomas of 3am Software Foundry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include <machine/asm.h> #include <sys/errno.h> RCSID("$NetBSD: n_scalbn.S,v 1.6 2022/04/04 19:33:44 andvar Exp $") WEAK_ALIAS(scalbn,_scalbn) WEAK_ALIAS(scalbnl,_scalbnl) WEAK_ALIAS(scalbnf,_scalbnf) WEAK_ALIAS(ldexp,_scalbn) WEAK_ALIAS(ldexpf,_scalbnf) WEAK_ALIAS(ldexpl,_scalbnl) ENTRY(_scalbnf, 0) cvtfd 4(%ap), %r0 movl 8(%ap), %r2 jr 1f ALTENTRY(_scalbnl) ENTRY(_scalbn, 0) movd 4(%ap), %r0 movl 12(%ap), %r2 /* * First see if the result will be within bounds */ 1: cmpl %r2,$(256+55) jgeq overflow cmpl %r2,$-(256+55) jleq underflow extzv $7, $9, %r0, %r3 /* extract exponent */ jneq 5f /* 0 * N is still 0 */ cmpw %r3, $-256 /* is this a NAN? */ jgtr 2f /* nope */ ret 2: movzbl %r3, %r3 /* clear sign bit */ addl2 %r2, %r3 /* add to exponent */ jleq underflow /* <= 0? */ 3: jbs $8, %r3, overflow /* did exponent overflow? */ insv $7, $8, %r3, %r0 /* replace exponent */ ret underflow: clrq %r0 /* return 0.0 */ jr copysign /* or maybe -0.0 */ overflow: pushl $ERANGE /* overflow */ calls $1, _C_LABEL(infnan) /* possibly signal */ copysign: jbc $15, 4(%ap), 5f /* if clear, don't set sign-bit */ bisw2 $0x8000, %r0 /* preserve sign-bit */ 5: ret |