1/*- 2 * Copyright (c) 2011 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by Matt Thomas of 3am Software Foundry. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include <machine/asm.h> 31#include <sys/errno.h> 32 33RCSID("$NetBSD: n_scalbn.S,v 1.4 2013/05/24 12:45:40 martin Exp $") 34 35WEAK_ALIAS(scalbn,_scalbn) 36WEAK_ALIAS(ldexp,_scalbn) 37WEAK_ALIAS(ldexpf,_scalbnf) 38WEAK_ALIAS(ldexpl,_scalbnl) 39 40ENTRY(_scalbnf, 0) 41 cvtfd 4(%ap), %r0 42 movl 8(%ap), %r2 43 jr 1f 44 45ALTENTRY(_scalbnl) 46ENTRY(_scalbn, 0) 47 movd 4(%ap), %r0 48 movl 12(%ap), %r2 49 50 /* 51 * First see if the result will be within bounds 52 */ 531: cmpl %r2,$(256+55) 54 jgeq overflow 55 cmpl %r2,$-(256+55) 56 jleq underflow 57 58 extzv $7, $9, %r0, %r3 /* extract exponent */ 59 jneq 5f /* 0 * N is still 0 */ 60 cmpw %r3, $-256 /* is this a NAN? */ 61 jgtr 2f /* nope */ 62 ret 63 642: movzbl %r3, %r3 /* clear sign bit */ 65 addl2 %r2, %r3 /* add to exponent */ 66 jleq underflow /* <= 0? */ 67 683: jbs $8, %r3, overflow /* did exponent overflow? */ 69 insv $7, $8, %r3, %r0 /* replace exponent */ 70 ret 71 72underflow: 73 clrq %r0 /* return 0.0 */ 74 jr copysign /* or mabye -0.0 */ 75overflow: 76 pushl $ERANGE /* overflow */ 77 calls $1, _C_LABEL(infnan) /* possibly signal */ 78copysign: 79 jbc $15, 4(%ap), 5f /* if clear, don't set sign-bit */ 80 bisw2 $0x8000, %r0 /* preserve sign-bit */ 815: 82 ret 83