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      1  1.5     skrll /*	$NetBSD: fcnvfxt.c,v 1.5 2012/02/04 17:03:09 skrll Exp $	*/
      2  1.1  fredette 
      3  1.4     skrll /*	$OpenBSD: fcnvfxt.c,v 1.8 2010/07/30 18:05:23 kettenis Exp $	*/
      4  1.1  fredette 
      5  1.1  fredette /*
      6  1.1  fredette  * Copyright 1996 1995 by Open Software Foundation, Inc.
      7  1.1  fredette  *              All Rights Reserved
      8  1.1  fredette  *
      9  1.1  fredette  * Permission to use, copy, modify, and distribute this software and
     10  1.1  fredette  * its documentation for any purpose and without fee is hereby granted,
     11  1.1  fredette  * provided that the above copyright notice appears in all copies and
     12  1.1  fredette  * that both the copyright notice and this permission notice appear in
     13  1.1  fredette  * supporting documentation.
     14  1.1  fredette  *
     15  1.1  fredette  * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
     16  1.1  fredette  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
     17  1.1  fredette  * FOR A PARTICULAR PURPOSE.
     18  1.1  fredette  *
     19  1.1  fredette  * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
     20  1.1  fredette  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
     21  1.1  fredette  * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
     22  1.1  fredette  * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
     23  1.1  fredette  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
     24  1.1  fredette  *
     25  1.1  fredette  */
     26  1.1  fredette /*
     27  1.1  fredette  * pmk1.1
     28  1.1  fredette  */
     29  1.1  fredette /*
     30  1.1  fredette  * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
     31  1.1  fredette  *
     32  1.1  fredette  * To anyone who acknowledges that this file is provided "AS IS"
     33  1.1  fredette  * without any express or implied warranty:
     34  1.1  fredette  *     permission to use, copy, modify, and distribute this file
     35  1.1  fredette  * for any purpose is hereby granted without fee, provided that
     36  1.1  fredette  * the above copyright notice and this notice appears in all
     37  1.1  fredette  * copies, and that the name of Hewlett-Packard Company not be
     38  1.1  fredette  * used in advertising or publicity pertaining to distribution
     39  1.1  fredette  * of the software without specific, written prior permission.
     40  1.1  fredette  * Hewlett-Packard Company makes no representations about the
     41  1.1  fredette  * suitability of this software for any purpose.
     42  1.1  fredette  */
     43  1.2     lukem 
     44  1.2     lukem #include <sys/cdefs.h>
     45  1.5     skrll __KERNEL_RCSID(0, "$NetBSD: fcnvfxt.c,v 1.5 2012/02/04 17:03:09 skrll Exp $");
     46  1.1  fredette 
     47  1.1  fredette #include "../spmath/float.h"
     48  1.1  fredette #include "../spmath/sgl_float.h"
     49  1.1  fredette #include "../spmath/dbl_float.h"
     50  1.1  fredette #include "../spmath/cnv_float.h"
     51  1.1  fredette 
     52  1.1  fredette /*
     53  1.1  fredette  *  Convert single floating-point to single fixed-point format
     54  1.1  fredette  *  with truncated result
     55  1.1  fredette  */
     56  1.1  fredette /*ARGSUSED*/
     57  1.1  fredette int
     58  1.5     skrll sgl_to_sgl_fcnvfxt(sgl_floating_point *srcptr, int *dstptr,
     59  1.5     skrll     unsigned int *status)
     60  1.1  fredette {
     61  1.1  fredette 	register unsigned int src, temp;
     62  1.1  fredette 	register int src_exponent, result;
     63  1.1  fredette 
     64  1.1  fredette 	src = *srcptr;
     65  1.1  fredette 	src_exponent = Sgl_exponent(src) - SGL_BIAS;
     66  1.1  fredette 
     67  1.1  fredette 	/*
     68  1.1  fredette 	 * Test for overflow
     69  1.1  fredette 	 */
     70  1.1  fredette 	if (src_exponent > SGL_FX_MAX_EXP) {
     71  1.1  fredette 		/* check for MININT */
     72  1.1  fredette 		if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
     73  1.1  fredette 		Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
     74  1.4     skrll 			if (Sgl_iszero_sign(src)) result = 0x7fffffff;
     75  1.4     skrll 			else result = 0x80000000;
     76  1.4     skrll 
     77  1.4     skrll 			if (Is_invalidtrap_enabled()) {
     78  1.4     skrll 				return(INVALIDEXCEPTION);
     79  1.4     skrll 			}
     80  1.4     skrll 			Set_invalidflag();
     81  1.4     skrll 			*dstptr = result;
     82  1.4     skrll 			return(NOEXCEPTION);
     83  1.1  fredette 		}
     84  1.1  fredette 	}
     85  1.1  fredette 	/*
     86  1.1  fredette 	 * Generate result
     87  1.1  fredette 	 */
     88  1.1  fredette 	if (src_exponent >= 0) {
     89  1.1  fredette 		temp = src;
     90  1.1  fredette 		Sgl_clear_signexponent_set_hidden(temp);
     91  1.1  fredette 		Int_from_sgl_mantissa(temp,src_exponent);
     92  1.1  fredette 		if (Sgl_isone_sign(src))  result = -Sgl_all(temp);
     93  1.1  fredette 		else result = Sgl_all(temp);
     94  1.1  fredette 		*dstptr = result;
     95  1.1  fredette 
     96  1.1  fredette 		/* check for inexact */
     97  1.1  fredette 		if (Sgl_isinexact_to_fix(src,src_exponent)) {
     98  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
     99  1.1  fredette 			else Set_inexactflag();
    100  1.1  fredette 		}
    101  1.1  fredette 	}
    102  1.1  fredette 	else {
    103  1.1  fredette 		*dstptr = 0;
    104  1.1  fredette 
    105  1.1  fredette 		/* check for inexact */
    106  1.1  fredette 		if (Sgl_isnotzero_exponentmantissa(src)) {
    107  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    108  1.1  fredette 			else Set_inexactflag();
    109  1.1  fredette 		}
    110  1.1  fredette 	}
    111  1.1  fredette 	return(NOEXCEPTION);
    112  1.1  fredette }
    113  1.1  fredette 
    114  1.1  fredette /*
    115  1.1  fredette  *  Single Floating-point to Double Fixed-point
    116  1.1  fredette  */
    117  1.1  fredette /*ARGSUSED*/
    118  1.1  fredette int
    119  1.5     skrll sgl_to_dbl_fcnvfxt(sgl_floating_point *srcptr, dbl_integer *dstptr,
    120  1.5     skrll     unsigned int *status)
    121  1.1  fredette {
    122  1.1  fredette 	register int src_exponent, resultp1;
    123  1.1  fredette 	register unsigned int src, temp, resultp2;
    124  1.1  fredette 
    125  1.1  fredette 	src = *srcptr;
    126  1.1  fredette 	src_exponent = Sgl_exponent(src) - SGL_BIAS;
    127  1.1  fredette 
    128  1.1  fredette 	/*
    129  1.1  fredette 	 * Test for overflow
    130  1.1  fredette 	 */
    131  1.1  fredette 	if (src_exponent > DBL_FX_MAX_EXP) {
    132  1.1  fredette 		/* check for MININT */
    133  1.1  fredette 		if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
    134  1.1  fredette 		Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
    135  1.4     skrll 			if (Sgl_iszero_sign(src)) {
    136  1.4     skrll 				resultp1 = 0x7fffffff;
    137  1.4     skrll 				resultp2 = 0xffffffff;
    138  1.4     skrll 			}
    139  1.4     skrll 			else {
    140  1.4     skrll 				resultp1 = 0x80000000;
    141  1.4     skrll 				resultp2 = 0;
    142  1.4     skrll 			}
    143  1.4     skrll 
    144  1.4     skrll 			if (Is_invalidtrap_enabled()) {
    145  1.4     skrll 				return(INVALIDEXCEPTION);
    146  1.4     skrll 			}
    147  1.4     skrll 			Set_invalidflag();
    148  1.4     skrll 			Dint_copytoptr(resultp1,resultp2,dstptr);
    149  1.4     skrll 			return(NOEXCEPTION);
    150  1.1  fredette 		}
    151  1.1  fredette 		Dint_set_minint(resultp1,resultp2);
    152  1.1  fredette 		Dint_copytoptr(resultp1,resultp2,dstptr);
    153  1.1  fredette 		return(NOEXCEPTION);
    154  1.1  fredette 	}
    155  1.1  fredette 	/*
    156  1.1  fredette 	 * Generate result
    157  1.1  fredette 	 */
    158  1.1  fredette 	if (src_exponent >= 0) {
    159  1.1  fredette 		temp = src;
    160  1.1  fredette 		Sgl_clear_signexponent_set_hidden(temp);
    161  1.1  fredette 		Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
    162  1.1  fredette 		if (Sgl_isone_sign(src)) {
    163  1.1  fredette 			Dint_setone_sign(resultp1,resultp2);
    164  1.1  fredette 		}
    165  1.1  fredette 		Dint_copytoptr(resultp1,resultp2,dstptr);
    166  1.1  fredette 
    167  1.1  fredette 		/* check for inexact */
    168  1.1  fredette 		if (Sgl_isinexact_to_fix(src,src_exponent)) {
    169  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    170  1.1  fredette 			else Set_inexactflag();
    171  1.1  fredette 		}
    172  1.1  fredette 	}
    173  1.1  fredette 	else {
    174  1.1  fredette 		Dint_setzero(resultp1,resultp2);
    175  1.1  fredette 		Dint_copytoptr(resultp1,resultp2,dstptr);
    176  1.1  fredette 
    177  1.1  fredette 		/* check for inexact */
    178  1.1  fredette 		if (Sgl_isnotzero_exponentmantissa(src)) {
    179  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    180  1.1  fredette 			else Set_inexactflag();
    181  1.1  fredette 		}
    182  1.1  fredette 	}
    183  1.1  fredette 	return(NOEXCEPTION);
    184  1.1  fredette }
    185  1.1  fredette 
    186  1.1  fredette /*
    187  1.1  fredette  *  Double Floating-point to Single Fixed-point
    188  1.1  fredette  */
    189  1.1  fredette /*ARGSUSED*/
    190  1.1  fredette int
    191  1.5     skrll dbl_to_sgl_fcnvfxt(dbl_floating_point *srcptr, int *dstptr,
    192  1.5     skrll     unsigned int *status)
    193  1.1  fredette {
    194  1.1  fredette 	register unsigned int srcp1, srcp2, tempp1, tempp2;
    195  1.1  fredette 	register int src_exponent, result;
    196  1.1  fredette 
    197  1.1  fredette 	Dbl_copyfromptr(srcptr,srcp1,srcp2);
    198  1.1  fredette 	src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
    199  1.1  fredette 
    200  1.1  fredette 	/*
    201  1.1  fredette 	 * Test for overflow
    202  1.1  fredette 	 */
    203  1.1  fredette 	if (src_exponent > SGL_FX_MAX_EXP) {
    204  1.1  fredette 		/* check for MININT */
    205  1.1  fredette 		if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
    206  1.4     skrll 			if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
    207  1.4     skrll 			else result = 0x80000000;
    208  1.4     skrll 
    209  1.4     skrll 			if (Is_invalidtrap_enabled()) {
    210  1.4     skrll 				return(INVALIDEXCEPTION);
    211  1.4     skrll 			}
    212  1.4     skrll 			Set_invalidflag();
    213  1.4     skrll 			*dstptr = result;
    214  1.4     skrll 			return(NOEXCEPTION);
    215  1.1  fredette 		}
    216  1.1  fredette 	}
    217  1.1  fredette 	/*
    218  1.1  fredette 	 * Generate result
    219  1.1  fredette 	 */
    220  1.1  fredette 	if (src_exponent >= 0) {
    221  1.1  fredette 		tempp1 = srcp1;
    222  1.1  fredette 		tempp2 = srcp2;
    223  1.1  fredette 		Dbl_clear_signexponent_set_hidden(tempp1);
    224  1.1  fredette 		Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
    225  1.1  fredette 		if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
    226  1.1  fredette 			result = -Dbl_allp1(tempp1);
    227  1.1  fredette 		else result = Dbl_allp1(tempp1);
    228  1.1  fredette 		*dstptr = result;
    229  1.1  fredette 
    230  1.1  fredette 		/* check for inexact */
    231  1.1  fredette 		if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
    232  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    233  1.1  fredette 			else Set_inexactflag();
    234  1.1  fredette 		}
    235  1.1  fredette 	}
    236  1.1  fredette 	else {
    237  1.1  fredette 		*dstptr = 0;
    238  1.1  fredette 
    239  1.1  fredette 		/* check for inexact */
    240  1.1  fredette 		if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
    241  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    242  1.1  fredette 			else Set_inexactflag();
    243  1.1  fredette 		}
    244  1.1  fredette 	}
    245  1.1  fredette 	return(NOEXCEPTION);
    246  1.1  fredette }
    247  1.1  fredette 
    248  1.1  fredette /*
    249  1.1  fredette  *  Double Floating-point to Double Fixed-point
    250  1.1  fredette  */
    251  1.1  fredette /*ARGSUSED*/
    252  1.1  fredette int
    253  1.5     skrll dbl_to_dbl_fcnvfxt(dbl_floating_point *srcptr, dbl_integer *dstptr,
    254  1.5     skrll     unsigned int *status)
    255  1.1  fredette {
    256  1.1  fredette 	register int src_exponent, resultp1;
    257  1.1  fredette 	register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
    258  1.1  fredette 
    259  1.1  fredette 	Dbl_copyfromptr(srcptr,srcp1,srcp2);
    260  1.1  fredette 	src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
    261  1.1  fredette 
    262  1.1  fredette 	/*
    263  1.1  fredette 	 * Test for overflow
    264  1.1  fredette 	 */
    265  1.1  fredette 	if (src_exponent > DBL_FX_MAX_EXP) {
    266  1.1  fredette 		/* check for MININT */
    267  1.1  fredette 		if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
    268  1.1  fredette 		Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
    269  1.4     skrll 			if (Dbl_iszero_sign(srcp1)) {
    270  1.4     skrll 				resultp1 = 0x7fffffff;
    271  1.4     skrll 				resultp2 = 0xffffffff;
    272  1.4     skrll 			}
    273  1.4     skrll 			else {
    274  1.4     skrll 				resultp1 = 0x80000000;
    275  1.4     skrll 				resultp2 = 0;
    276  1.4     skrll 			}
    277  1.4     skrll 
    278  1.4     skrll 			if (Is_invalidtrap_enabled()) {
    279  1.4     skrll 				return(INVALIDEXCEPTION);
    280  1.4     skrll 			}
    281  1.4     skrll 			Set_invalidflag();
    282  1.4     skrll 			Dint_copytoptr(resultp1,resultp2,dstptr);
    283  1.4     skrll 			return(NOEXCEPTION);
    284  1.1  fredette 		}
    285  1.1  fredette 	}
    286  1.1  fredette 	/*
    287  1.1  fredette 	 * Generate result
    288  1.1  fredette 	 */
    289  1.1  fredette 	if (src_exponent >= 0) {
    290  1.1  fredette 		tempp1 = srcp1;
    291  1.1  fredette 		tempp2 = srcp2;
    292  1.1  fredette 		Dbl_clear_signexponent_set_hidden(tempp1);
    293  1.1  fredette 		Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
    294  1.1  fredette 		resultp1,resultp2);
    295  1.1  fredette 		if (Dbl_isone_sign(srcp1)) {
    296  1.1  fredette 			Dint_setone_sign(resultp1,resultp2);
    297  1.1  fredette 		}
    298  1.1  fredette 		Dint_copytoptr(resultp1,resultp2,dstptr);
    299  1.1  fredette 
    300  1.1  fredette 		/* check for inexact */
    301  1.1  fredette 		if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
    302  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    303  1.1  fredette 			else Set_inexactflag();
    304  1.1  fredette 		}
    305  1.1  fredette 	}
    306  1.1  fredette 	else {
    307  1.1  fredette 		Dint_setzero(resultp1,resultp2);
    308  1.1  fredette 		Dint_copytoptr(resultp1,resultp2,dstptr);
    309  1.1  fredette 
    310  1.1  fredette 		/* check for inexact */
    311  1.1  fredette 		if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
    312  1.1  fredette 			if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
    313  1.1  fredette 			else Set_inexactflag();
    314  1.1  fredette 		}
    315  1.1  fredette 	}
    316  1.1  fredette 	return(NOEXCEPTION);
    317  1.1  fredette }
    318