usr/src/lib/libc/sparcv9/fp/_Qp_qtox.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1994-1997, by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include "quad.h"
  30
  31 /*
  32  * _Qp_qtox(x) returns (long)*x.
  33  */
  34 long
  35 _Qp_qtox(const union longdouble *x)
  36 {
  37         long            i, round;
  38         unsigned int    xm, fsr;
  39
  40         xm = x->l.msw & 0x7fffffff;
  41
  42         __quad_getfsrp(&fsr);
  43
  44         /* handle nan, inf, and out-of-range cases */
  45         if (xm >= 0x403e0000) {
  46                 if (x->l.msw == 0xc03e0000 && x->l.frac2 == 0 &&
  47                     (x->l.frac3 & 0xfffe0000) == 0) {
  48                         /* return largest negative 64 bit int */
  49                         i = 0x8000000000000000ul;
  50                         if ((x->l.frac3 & 0x1ffff) | x->l.frac4) {
  51                                 /* signal inexact */
  52                                 if (fsr & FSR_NXM) {
  53                                         __quad_fqtox(x, &i);
  54                                 } else {
  55                                         fsr = (fsr & ~FSR_CEXC) | FSR_NXA |
  56                                             FSR_NXC;
  57                                         __quad_setfsrp(&fsr);
  58                                 }
  59                         }
  60                         return (i);
  61                 }
  62                 i = ((x->l.msw & 0x80000000)? 0x8000000000000000ul :
  63                     0x7fffffffffffffffl);
  64                 if (fsr & FSR_NVM) {
  65                         __quad_fqtox(x, &i);
  66                 } else {
  67                         fsr = (fsr & ~FSR_CEXC) | FSR_NVA | FSR_NVC;
  68                         __quad_setfsrp(&fsr);
  69                 }
  70                 return (i);
  71         }
  72         if (xm < 0x3fff0000) {
  73                 i = 0l;
  74                 if (xm | x->l.frac2 | x->l.frac3 | x->l.frac4) {
  75                         /* signal inexact */
  76                         if (fsr & FSR_NXM) {
  77                                 __quad_fqtox(x, &i);
  78                         } else {
  79                                 fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
  80                                 __quad_setfsrp(&fsr);
  81                         }
  82                 }
  83                 return (i);
  84         }
  85
  86         /* now x is in the range of 64 bit int */
  87         i = 0x4000000000000000l | ((long) (xm & 0xffff) << 46) |
  88             ((long) x->l.frac2 << 14) | (x->l.frac3 >> 18);
  89         round = i & ((1l << (0x403d - (xm >> 16))) - 1);
  90         i >>= (0x403d - (xm >> 16));
  91         if (x->l.msw & 0x80000000)
  92                 i = -i;
  93         if (round | (x->l.frac3 & 0x3ffff) | x->l.frac4) {
  94                 /* signal inexact */
  95                 if (fsr & FSR_NXM) {
  96                         __quad_fqtox(x, &i);
  97                 } else {
  98                         fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
  99                         __quad_setfsrp(&fsr);
 100                 }
 101         }
 102         return (i);
 103 }