n_scalbn.S revision 1.1
11.1Smatt/*- 21.1Smatt * Copyright (c) 2011 The NetBSD Foundation, Inc. 31.1Smatt * All rights reserved. 41.1Smatt * 51.1Smatt * This code is derived from software contributed to The NetBSD Foundation 61.1Smatt * by Matt Thomas of 3am Software Foundry. 71.1Smatt * 81.1Smatt * Redistribution and use in source and binary forms, with or without 91.1Smatt * modification, are permitted provided that the following conditions 101.1Smatt * are met: 111.1Smatt * 1. Redistributions of source code must retain the above copyright 121.1Smatt * notice, this list of conditions and the following disclaimer. 131.1Smatt * 2. Redistributions in binary form must reproduce the above copyright 141.1Smatt * notice, this list of conditions and the following disclaimer in the 151.1Smatt * documentation and/or other materials provided with the distribution. 161.1Smatt * 171.1Smatt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 181.1Smatt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 191.1Smatt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 201.1Smatt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 211.1Smatt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 221.1Smatt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 231.1Smatt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 241.1Smatt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 251.1Smatt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 261.1Smatt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 271.1Smatt * POSSIBILITY OF SUCH DAMAGE. 281.1Smatt */ 291.1Smatt 301.1Smatt#include <machine/asm.h> 311.1Smatt#include <sys/errno.h> 321.1Smatt 331.1SmattRCSID("$NetBSD: n_scalbn.S,v 1.1 2011/07/28 20:53:20 matt Exp $") 341.1Smatt 351.1SmattENTRY(scalbnf, 0) 361.1Smatt cvtfd 4(%ap), %r0 371.1Smatt movl 8(%ap), %r2 381.1Smatt jr 1f 391.1Smatt 401.1SmattALTENTRY(scalbnl) 411.1SmattENTRY(scalbn, 0) 421.1Smatt movd 4(%ap), %r0 431.1Smatt movl 12(%ap), %r2 441.1Smatt 451.1Smatt /* 461.1Smatt * First see if the result will be within bounds 471.1Smatt */ 481.1Smatt1: cmpl %r2,$(256+55) 491.1Smatt jgeq overflow 501.1Smatt cmpl %r2,$-(256+55) 511.1Smatt jleq underflow 521.1Smatt 531.1Smatt extzv $7, $9, %r0, %r3 /* extract exponent */ 541.1Smatt jneq 5f /* 0 * N is still 0 */ 551.1Smatt cmpw %r3, $-256 /* is this a NAN? */ 561.1Smatt jgtr 2f /* nope */ 571.1Smatt ret 581.1Smatt 591.1Smatt2: movzbl %r3, %r3 /* clear sign bit */ 601.1Smatt addl2 %r2, %r3 /* add to exponent */ 611.1Smatt jleq underflow /* <= 0? */ 621.1Smatt 631.1Smatt3: jbs $8, %r3, overflow /* did exponent overflow? */ 641.1Smatt insv $7, $8, %r3, %r0 /* replace exponent */ 651.1Smatt ret 661.1Smatt 671.1Smattunderflow: 681.1Smatt clrq %r0 /* return 0.0 */ 691.1Smatt jr copysign /* or mabye -0.0 */ 701.1Smattoverflow: 711.1Smatt pushl $ERANGE /* overflow */ 721.1Smatt calls $1, _C_LABEL(infnan) /* possibly signal */ 731.1Smattcopysign: 741.1Smatt jbc $15, 4(%ap), 5f /* if clear, don't set sign-bit */ 751.1Smatt bisw2 $0x8000, %r0 /* preserve sign-bit */ 761.1Smatt5: 771.1Smatt ret 78