NetBSD-5.0.2/sys/arch/hppa/spmath/fcnvxf.c
/* $NetBSD: fcnvxf.c,v 1.3 2005/12/11 12:17:40 christos Exp $ */
/* $OpenBSD: fcnvxf.c,v 1.5 2001/03/29 03:58:18 mickey Exp $ */
/*
* Copyright 1996 1995 by Open Software Foundation, Inc.
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both the copyright notice and this permission notice appear in
* supporting documentation.
*
* OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
* NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
/*
* pmk1.1
*/
/*
* (c) Copyright 1986 HEWLETT-PACKARD COMPANY
*
* To anyone who acknowledges that this file is provided "AS IS"
* without any express or implied warranty:
* permission to use, copy, modify, and distribute this file
* for any purpose is hereby granted without fee, provided that
* the above copyright notice and this notice appears in all
* copies, and that the name of Hewlett-Packard Company not be
* used in advertising or publicity pertaining to distribution
* of the software without specific, written prior permission.
* Hewlett-Packard Company makes no representations about the
* suitability of this software for any purpose.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fcnvxf.c,v 1.3 2005/12/11 12:17:40 christos Exp $");
#include "../spmath/float.h"
#include "../spmath/sgl_float.h"
#include "../spmath/dbl_float.h"
#include "../spmath/cnv_float.h"
/*
* Convert single fixed-point to single floating-point format
*/
int
sgl_to_sgl_fcnvxf(srcptr,dstptr,status)
int *srcptr;
sgl_floating_point *dstptr;
unsigned int *status;
{
register int src, dst_exponent;
register unsigned int result = 0;
src = *srcptr;
/*
* set sign bit of result and get magnitude of source
*/
if (src < 0) {
Sgl_setone_sign(result);
Int_negate(src);
}
else {
Sgl_setzero_sign(result);
/* Check for zero */
if (src == 0) {
Sgl_setzero(result);
*dstptr = result;
return(NOEXCEPTION);
}
}
/*
* Generate exponent and normalized mantissa
*/
dst_exponent = 16; /* initialize for normalization */
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*/
Find_ms_one_bit(src,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent >= 0) src <<= dst_exponent;
else src = 1 << 30;
Sgl_set_mantissa(result, src >> (SGL_EXP_LENGTH-1));
Sgl_set_exponent(result, 30+SGL_BIAS - dst_exponent);
/* check for inexact */
if (Int_isinexact_to_sgl(src)) {
switch (Rounding_mode()) {
case ROUNDPLUS:
if (Sgl_iszero_sign(result))
Sgl_increment(result);
break;
case ROUNDMINUS:
if (Sgl_isone_sign(result))
Sgl_increment(result);
break;
case ROUNDNEAREST:
Sgl_roundnearest_from_int(src,result);
}
if (Is_inexacttrap_enabled()) {
*dstptr = result;
return(INEXACTEXCEPTION);
}
else Set_inexactflag();
}
*dstptr = result;
return(NOEXCEPTION);
}
/*
* Single Fixed-point to Double Floating-point
*/
int
sgl_to_dbl_fcnvxf(srcptr,dstptr,status)
int *srcptr;
dbl_floating_point *dstptr;
unsigned int *status;
{
register int src, dst_exponent;
register unsigned int resultp1 = 0, resultp2 = 0;
src = *srcptr;
/*
* set sign bit of result and get magnitude of source
*/
if (src < 0) {
Dbl_setone_sign(resultp1);
Int_negate(src);
}
else {
Dbl_setzero_sign(resultp1);
/* Check for zero */
if (src == 0) {
Dbl_setzero(resultp1,resultp2);
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(NOEXCEPTION);
}
}
/*
* Generate exponent and normalized mantissa
*/
dst_exponent = 16; /* initialize for normalization */
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*/
Find_ms_one_bit(src,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent >= 0) src <<= dst_exponent;
else src = 1 << 30;
Dbl_set_mantissap1(resultp1, (src >> (DBL_EXP_LENGTH - 1)));
Dbl_set_mantissap2(resultp2, (src << (33-DBL_EXP_LENGTH)));
Dbl_set_exponent(resultp1, (30+DBL_BIAS) - dst_exponent);
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(NOEXCEPTION);
}
/*
* Double Fixed-point to Single Floating-point
*/
int
dbl_to_sgl_fcnvxf(srcptr,dstptr,status)
dbl_integer *srcptr;
sgl_floating_point *dstptr;
unsigned int *status;
{
int dst_exponent, srcp1;
unsigned int result = 0, srcp2;
Dint_copyfromptr(srcptr,srcp1,srcp2);
/*
* set sign bit of result and get magnitude of source
*/
if (srcp1 < 0) {
Sgl_setone_sign(result);
Dint_negate(srcp1,srcp2);
}
else {
Sgl_setzero_sign(result);
/* Check for zero */
if (srcp1 == 0 && srcp2 == 0) {
Sgl_setzero(result);
*dstptr = result;
return(NOEXCEPTION);
}
}
/*
* Generate exponent and normalized mantissa
*/
dst_exponent = 16; /* initialize for normalization */
if (srcp1 == 0) {
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*/
Find_ms_one_bit(srcp2,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent >= 0) {
srcp1 = srcp2 << dst_exponent;
srcp2 = 0;
}
else {
srcp1 = srcp2 >> 1;
srcp2 <<= 31;
}
/*
* since msb set is in second word, need to
* adjust bit position count
*/
dst_exponent += 32;
}
else {
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*
*/
Find_ms_one_bit(srcp1,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent > 0) {
Variable_shift_double(srcp1,srcp2,(32-dst_exponent),
srcp1);
srcp2 <<= dst_exponent;
}
/*
* If dst_exponent = 0, we don't need to shift anything.
* If dst_exponent = -1, src = - 2**63 so we won't need to
* shift srcp2.
*/
else srcp1 >>= -(dst_exponent);
}
Sgl_set_mantissa(result, (srcp1 >> (SGL_EXP_LENGTH - 1)));
Sgl_set_exponent(result, (62+SGL_BIAS) - dst_exponent);
/* check for inexact */
if (Dint_isinexact_to_sgl(srcp1,srcp2)) {
switch (Rounding_mode()) {
case ROUNDPLUS:
if (Sgl_iszero_sign(result))
Sgl_increment(result);
break;
case ROUNDMINUS:
if (Sgl_isone_sign(result))
Sgl_increment(result);
break;
case ROUNDNEAREST:
Sgl_roundnearest_from_dint(srcp1,srcp2,result);
}
if (Is_inexacttrap_enabled()) {
*dstptr = result;
return(INEXACTEXCEPTION);
}
else Set_inexactflag();
}
*dstptr = result;
return(NOEXCEPTION);
}
/*
* Double Fixed-point to Double Floating-point
*/
int
dbl_to_dbl_fcnvxf(srcptr,dstptr,status)
dbl_integer *srcptr;
dbl_floating_point *dstptr;
unsigned int *status;
{
register int srcp1, dst_exponent;
register unsigned int srcp2, resultp1 = 0, resultp2 = 0;
Dint_copyfromptr(srcptr,srcp1,srcp2);
/*
* set sign bit of result and get magnitude of source
*/
if (srcp1 < 0) {
Dbl_setone_sign(resultp1);
Dint_negate(srcp1,srcp2);
}
else {
Dbl_setzero_sign(resultp1);
/* Check for zero */
if (srcp1 == 0 && srcp2 ==0) {
Dbl_setzero(resultp1,resultp2);
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(NOEXCEPTION);
}
}
/*
* Generate exponent and normalized mantissa
*/
dst_exponent = 16; /* initialize for normalization */
if (srcp1 == 0) {
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*/
Find_ms_one_bit(srcp2,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent >= 0) {
srcp1 = srcp2 << dst_exponent;
srcp2 = 0;
}
else {
srcp1 = srcp2 >> 1;
srcp2 <<= 31;
}
/*
* since msb set is in second word, need to
* adjust bit position count
*/
dst_exponent += 32;
}
else {
/*
* Check word for most significant bit set. Returns
* a value in dst_exponent indicating the bit position,
* between -1 and 30.
*/
Find_ms_one_bit(srcp1,dst_exponent);
/* left justify source, with msb at bit position 1 */
if (dst_exponent > 0) {
Variable_shift_double(srcp1,srcp2,(32-dst_exponent),
srcp1);
srcp2 <<= dst_exponent;
}
/*
* If dst_exponent = 0, we don't need to shift anything.
* If dst_exponent = -1, src = - 2**63 so we won't need to
* shift srcp2.
*/
else srcp1 >>= -(dst_exponent);
}
Dbl_set_mantissap1(resultp1, srcp1 >> (DBL_EXP_LENGTH-1));
Shiftdouble(srcp1,srcp2,DBL_EXP_LENGTH-1,resultp2);
Dbl_set_exponent(resultp1, (62+DBL_BIAS) - dst_exponent);
/* check for inexact */
if (Dint_isinexact_to_dbl(srcp2)) {
switch (Rounding_mode()) {
case ROUNDPLUS:
if (Dbl_iszero_sign(resultp1)) {
Dbl_increment(resultp1,resultp2);
}
break;
case ROUNDMINUS:
if (Dbl_isone_sign(resultp1)) {
Dbl_increment(resultp1,resultp2);
}
break;
case ROUNDNEAREST:
Dbl_roundnearest_from_dint(srcp2,resultp1,
resultp2);
}
if (Is_inexacttrap_enabled()) {
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(INEXACTEXCEPTION);
}
else Set_inexactflag();
}
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(NOEXCEPTION);
}