253 lines
7 KiB
C
253 lines
7 KiB
C
|
/*
|
||
|
|
* Linux/PA-RISC Project (http://www.parisc-linux.org/)
|
||
|
|
*
|
||
|
|
* Floating-point emulation code
|
||
|
|
* Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License as published by
|
||
|
|
* the Free Software Foundation; either version 2, or (at your option)
|
||
|
|
* any later version.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU General Public License
|
||
|
|
* along with this program; if not, write to the Free Software
|
||
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
||
|
|
*/
|
||
|
|
/*
|
||
|
|
* BEGIN_DESC
|
||
|
|
*
|
||
|
|
* Purpose:
|
||
|
|
* Single Floating-point Round to Integer
|
||
|
|
* Double Floating-point Round to Integer
|
||
|
|
* Quad Floating-point Round to Integer (returns unimplemented)
|
||
|
|
*
|
||
|
|
* External Interfaces:
|
||
|
|
* dbl_frnd(srcptr,nullptr,dstptr,status)
|
||
|
|
* sgl_frnd(srcptr,nullptr,dstptr,status)
|
||
|
|
*
|
||
|
|
* END_DESC
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
#include "float.h"
|
||
|
|
#include "sgl_float.h"
|
||
|
|
#include "dbl_float.h"
|
||
|
|
#include "cnv_float.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Single Floating-point Round to Integer
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*ARGSUSED*/
|
||
|
|
int
|
||
|
|
sgl_frnd(sgl_floating_point *srcptr,
|
||
|
|
unsigned int *nullptr,
|
||
|
|
sgl_floating_point *dstptr,
|
||
|
|
unsigned int *status)
|
||
|
|
{
|
||
|
|
register unsigned int src, result;
|
||
|
|
register int src_exponent;
|
||
|
|
register boolean inexact = FALSE;
|
||
|
|
|
||
|
|
src = *srcptr;
|
||
|
|
/*
|
||
|
|
* check source operand for NaN or infinity
|
||
|
|
*/
|
||
|
|
if ((src_exponent = Sgl_exponent(src)) == SGL_INFINITY_EXPONENT) {
|
||
|
|
/*
|
||
|
|
* is signaling NaN?
|
||
|
|
*/
|
||
|
|
if (Sgl_isone_signaling(src)) {
|
||
|
|
/* trap if INVALIDTRAP enabled */
|
||
|
|
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
|
||
|
|
/* make NaN quiet */
|
||
|
|
Set_invalidflag();
|
||
|
|
Sgl_set_quiet(src);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* return quiet NaN or infinity
|
||
|
|
*/
|
||
|
|
*dstptr = src;
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* Need to round?
|
||
|
|
*/
|
||
|
|
if ((src_exponent -= SGL_BIAS) >= SGL_P - 1) {
|
||
|
|
*dstptr = src;
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* Generate result
|
||
|
|
*/
|
||
|
|
if (src_exponent >= 0) {
|
||
|
|
Sgl_clear_exponent_set_hidden(src);
|
||
|
|
result = src;
|
||
|
|
Sgl_rightshift(result,(SGL_P-1) - (src_exponent));
|
||
|
|
/* check for inexact */
|
||
|
|
if (Sgl_isinexact_to_fix(src,src_exponent)) {
|
||
|
|
inexact = TRUE;
|
||
|
|
/* round result */
|
||
|
|
switch (Rounding_mode()) {
|
||
|
|
case ROUNDPLUS:
|
||
|
|
if (Sgl_iszero_sign(src)) Sgl_increment(result);
|
||
|
|
break;
|
||
|
|
case ROUNDMINUS:
|
||
|
|
if (Sgl_isone_sign(src)) Sgl_increment(result);
|
||
|
|
break;
|
||
|
|
case ROUNDNEAREST:
|
||
|
|
if (Sgl_isone_roundbit(src,src_exponent))
|
||
|
|
if (Sgl_isone_stickybit(src,src_exponent)
|
||
|
|
|| (Sgl_isone_lowmantissa(result)))
|
||
|
|
Sgl_increment(result);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
Sgl_leftshift(result,(SGL_P-1) - (src_exponent));
|
||
|
|
if (Sgl_isone_hiddenoverflow(result))
|
||
|
|
Sgl_set_exponent(result,src_exponent + (SGL_BIAS+1));
|
||
|
|
else Sgl_set_exponent(result,src_exponent + SGL_BIAS);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
result = src; /* set sign */
|
||
|
|
Sgl_setzero_exponentmantissa(result);
|
||
|
|
/* check for inexact */
|
||
|
|
if (Sgl_isnotzero_exponentmantissa(src)) {
|
||
|
|
inexact = TRUE;
|
||
|
|
/* round result */
|
||
|
|
switch (Rounding_mode()) {
|
||
|
|
case ROUNDPLUS:
|
||
|
|
if (Sgl_iszero_sign(src))
|
||
|
|
Sgl_set_exponent(result,SGL_BIAS);
|
||
|
|
break;
|
||
|
|
case ROUNDMINUS:
|
||
|
|
if (Sgl_isone_sign(src))
|
||
|
|
Sgl_set_exponent(result,SGL_BIAS);
|
||
|
|
break;
|
||
|
|
case ROUNDNEAREST:
|
||
|
|
if (src_exponent == -1)
|
||
|
|
if (Sgl_isnotzero_mantissa(src))
|
||
|
|
Sgl_set_exponent(result,SGL_BIAS);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
*dstptr = result;
|
||
|
|
if (inexact) {
|
||
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
||
|
|
else Set_inexactflag();
|
||
|
|
}
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Double Floating-point Round to Integer
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*ARGSUSED*/
|
||
|
|
int
|
||
|
|
dbl_frnd(
|
||
|
|
dbl_floating_point *srcptr,
|
||
|
|
unsigned int *nullptr,
|
||
|
|
dbl_floating_point *dstptr,
|
||
|
|
unsigned int *status)
|
||
|
|
{
|
||
|
|
register unsigned int srcp1, srcp2, resultp1, resultp2;
|
||
|
|
register int src_exponent;
|
||
|
|
register boolean inexact = FALSE;
|
||
|
|
|
||
|
|
Dbl_copyfromptr(srcptr,srcp1,srcp2);
|
||
|
|
/*
|
||
|
|
* check source operand for NaN or infinity
|
||
|
|
*/
|
||
|
|
if ((src_exponent = Dbl_exponent(srcp1)) == DBL_INFINITY_EXPONENT) {
|
||
|
|
/*
|
||
|
|
* is signaling NaN?
|
||
|
|
*/
|
||
|
|
if (Dbl_isone_signaling(srcp1)) {
|
||
|
|
/* trap if INVALIDTRAP enabled */
|
||
|
|
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
|
||
|
|
/* make NaN quiet */
|
||
|
|
Set_invalidflag();
|
||
|
|
Dbl_set_quiet(srcp1);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* return quiet NaN or infinity
|
||
|
|
*/
|
||
|
|
Dbl_copytoptr(srcp1,srcp2,dstptr);
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* Need to round?
|
||
|
|
*/
|
||
|
|
if ((src_exponent -= DBL_BIAS) >= DBL_P - 1) {
|
||
|
|
Dbl_copytoptr(srcp1,srcp2,dstptr);
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* Generate result
|
||
|
|
*/
|
||
|
|
if (src_exponent >= 0) {
|
||
|
|
Dbl_clear_exponent_set_hidden(srcp1);
|
||
|
|
resultp1 = srcp1;
|
||
|
|
resultp2 = srcp2;
|
||
|
|
Dbl_rightshift(resultp1,resultp2,(DBL_P-1) - (src_exponent));
|
||
|
|
/* check for inexact */
|
||
|
|
if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
|
||
|
|
inexact = TRUE;
|
||
|
|
/* round result */
|
||
|
|
switch (Rounding_mode()) {
|
||
|
|
case ROUNDPLUS:
|
||
|
|
if (Dbl_iszero_sign(srcp1))
|
||
|
|
Dbl_increment(resultp1,resultp2);
|
||
|
|
break;
|
||
|
|
case ROUNDMINUS:
|
||
|
|
if (Dbl_isone_sign(srcp1))
|
||
|
|
Dbl_increment(resultp1,resultp2);
|
||
|
|
break;
|
||
|
|
case ROUNDNEAREST:
|
||
|
|
if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
|
||
|
|
if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent)
|
||
|
|
|| (Dbl_isone_lowmantissap2(resultp2)))
|
||
|
|
Dbl_increment(resultp1,resultp2);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
Dbl_leftshift(resultp1,resultp2,(DBL_P-1) - (src_exponent));
|
||
|
|
if (Dbl_isone_hiddenoverflow(resultp1))
|
||
|
|
Dbl_set_exponent(resultp1,src_exponent + (DBL_BIAS+1));
|
||
|
|
else Dbl_set_exponent(resultp1,src_exponent + DBL_BIAS);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
resultp1 = srcp1; /* set sign */
|
||
|
|
Dbl_setzero_exponentmantissa(resultp1,resultp2);
|
||
|
|
/* check for inexact */
|
||
|
|
if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
|
||
|
|
inexact = TRUE;
|
||
|
|
/* round result */
|
||
|
|
switch (Rounding_mode()) {
|
||
|
|
case ROUNDPLUS:
|
||
|
|
if (Dbl_iszero_sign(srcp1))
|
||
|
|
Dbl_set_exponent(resultp1,DBL_BIAS);
|
||
|
|
break;
|
||
|
|
case ROUNDMINUS:
|
||
|
|
if (Dbl_isone_sign(srcp1))
|
||
|
|
Dbl_set_exponent(resultp1,DBL_BIAS);
|
||
|
|
break;
|
||
|
|
case ROUNDNEAREST:
|
||
|
|
if (src_exponent == -1)
|
||
|
|
if (Dbl_isnotzero_mantissa(srcp1,srcp2))
|
||
|
|
Dbl_set_exponent(resultp1,DBL_BIAS);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
||
|
|
if (inexact) {
|
||
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
||
|
|
else Set_inexactflag();
|
||
|
|
}
|
||
|
|
return(NOEXCEPTION);
|
||
|
|
}
|