/*- * Copyright (c) 1985 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * Computer Consoles Inc. * * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. * * @(#)Kcvtdl.s 7.1 (Berkeley) 12/6/90 */ #include "../math/fp.h" #include "../math/Kfp.h" #include "../tahoe/SYS.h" .text .globl _Kcvtdl .globl _Kcvtdu _Kcvtdu: _Kcvtdl: .word R5|R4|R3|R2 # #Some initializations: # clrl r3 # r3 - negative flag. movl 4(fp),r0 # fetch operand. movl 8(fp),r1 # #get exponent # andl3 $EXPMASK,r0,r2 # r2 will hold the exponent. jeql retzero cmpl $TWO_EXP,r2 # if exponent is less then -2,return zero. jgtr retzero andl2 $0!EXPSIGN,r2 # turn off biased exponent sign shrl $EXPSHIFT,r2,r2 # #get fraction # bbc $31,r0,positive # if negative remember it. incl r3 positive: # clear the non fraction parts. andl2 $(0!(EXPMASK | SIGNBIT)),r0 # add the hidden bit. orl2 $(0!CLEARHID),r0 subl2 $24,r2 # compute the shift. jgtr shift_left mnegl r2,r2 shrl r2,r0,r0 # shift right. jmp shifted shift_left: cmpl r2,$7 jgtr overflow go_on: shlq r2,r0,r0 # shift right. shifted: bbc $0,r3,done # check for negative mnegl r0,r0 done: ret retzero: clrl r0 ret overflow: ret