mirror of
https://github.com/torvalds/linux.git
synced 2024-11-01 01:31:44 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
537 lines
12 KiB
C
537 lines
12 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
|
|
*
|
|
* File:
|
|
* @(#) pa/spmath/fcnvfu.c $Revision: 1.1 $
|
|
*
|
|
* Purpose:
|
|
* Floating-point to Unsigned Fixed-point Converts
|
|
*
|
|
* External Interfaces:
|
|
* dbl_to_dbl_fcnvfu(srcptr,nullptr,dstptr,status)
|
|
* dbl_to_sgl_fcnvfu(srcptr,nullptr,dstptr,status)
|
|
* sgl_to_dbl_fcnvfu(srcptr,nullptr,dstptr,status)
|
|
* sgl_to_sgl_fcnvfu(srcptr,nullptr,dstptr,status)
|
|
*
|
|
* Internal Interfaces:
|
|
*
|
|
* Theory:
|
|
* <<please update with a overview of the operation of this file>>
|
|
*
|
|
* END_DESC
|
|
*/
|
|
|
|
|
|
#include "float.h"
|
|
#include "sgl_float.h"
|
|
#include "dbl_float.h"
|
|
#include "cnv_float.h"
|
|
|
|
/************************************************************************
|
|
* Floating-point to Unsigned Fixed-point Converts *
|
|
************************************************************************/
|
|
|
|
/*
|
|
* Single Floating-point to Single Unsigned Fixed
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
sgl_to_sgl_fcnvfu(
|
|
sgl_floating_point *srcptr,
|
|
unsigned int *nullptr,
|
|
unsigned int *dstptr,
|
|
unsigned int *status)
|
|
{
|
|
register unsigned int src, result;
|
|
register int src_exponent;
|
|
register boolean inexact = FALSE;
|
|
|
|
src = *srcptr;
|
|
src_exponent = Sgl_exponent(src) - SGL_BIAS;
|
|
|
|
/*
|
|
* Test for overflow
|
|
*/
|
|
if (src_exponent > SGL_FX_MAX_EXP + 1) {
|
|
if (Sgl_isone_sign(src)) {
|
|
result = 0;
|
|
} else {
|
|
result = 0xffffffff;
|
|
}
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* Generate result
|
|
*/
|
|
if (src_exponent >= 0) {
|
|
/*
|
|
* Check sign.
|
|
* If negative, trap unimplemented.
|
|
*/
|
|
if (Sgl_isone_sign(src)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
Sgl_clear_signexponent_set_hidden(src);
|
|
Suint_from_sgl_mantissa(src,src_exponent,result);
|
|
|
|
/* check for inexact */
|
|
if (Sgl_isinexact_to_unsigned(src,src_exponent)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
result++;
|
|
break;
|
|
case ROUNDMINUS: /* never negative */
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (Sgl_isone_roundbit(src,src_exponent) &&
|
|
(Sgl_isone_stickybit(src,src_exponent) ||
|
|
(result & 1))) {
|
|
result++;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
result = 0;
|
|
|
|
/* check for inexact */
|
|
if (Sgl_isnotzero_exponentmantissa(src)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
if (Sgl_iszero_sign(src)) {
|
|
result++;
|
|
}
|
|
break;
|
|
case ROUNDMINUS:
|
|
if (Sgl_isone_sign(src)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (src_exponent == -1 &&
|
|
Sgl_isnotzero_mantissa(src)) {
|
|
if (Sgl_isone_sign(src)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
else result++;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
*dstptr = result;
|
|
if (inexact) {
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
}
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Single Floating-point to Double Unsigned Fixed
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
sgl_to_dbl_fcnvfu(
|
|
sgl_floating_point *srcptr,
|
|
unsigned int *nullptr,
|
|
dbl_unsigned *dstptr,
|
|
unsigned int *status)
|
|
{
|
|
register int src_exponent;
|
|
register unsigned int src, resultp1, resultp2;
|
|
register boolean inexact = FALSE;
|
|
|
|
src = *srcptr;
|
|
src_exponent = Sgl_exponent(src) - SGL_BIAS;
|
|
|
|
/*
|
|
* Test for overflow
|
|
*/
|
|
if (src_exponent > DBL_FX_MAX_EXP + 1) {
|
|
if (Sgl_isone_sign(src)) {
|
|
resultp1 = resultp2 = 0;
|
|
} else {
|
|
resultp1 = resultp2 = 0xffffffff;
|
|
}
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* Generate result
|
|
*/
|
|
if (src_exponent >= 0) {
|
|
/*
|
|
* Check sign.
|
|
* If negative, trap unimplemented.
|
|
*/
|
|
if (Sgl_isone_sign(src)) {
|
|
resultp1 = resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
Sgl_clear_signexponent_set_hidden(src);
|
|
Duint_from_sgl_mantissa(src,src_exponent,resultp1,resultp2);
|
|
|
|
/* check for inexact */
|
|
if (Sgl_isinexact_to_unsigned(src,src_exponent)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
Duint_increment(resultp1,resultp2);
|
|
break;
|
|
case ROUNDMINUS: /* never negative */
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (Sgl_isone_roundbit(src,src_exponent) &&
|
|
(Sgl_isone_stickybit(src,src_exponent) ||
|
|
Duint_isone_lowp2(resultp2))) {
|
|
Duint_increment(resultp1,resultp2);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
Duint_setzero(resultp1,resultp2);
|
|
|
|
/* check for inexact */
|
|
if (Sgl_isnotzero_exponentmantissa(src)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
if (Sgl_iszero_sign(src)) {
|
|
Duint_increment(resultp1,resultp2);
|
|
}
|
|
break;
|
|
case ROUNDMINUS:
|
|
if (Sgl_isone_sign(src)) {
|
|
resultp1 = resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (src_exponent == -1 &&
|
|
Sgl_isnotzero_mantissa(src)) {
|
|
if (Sgl_isone_sign(src)) {
|
|
resultp1 = 0;
|
|
resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
else Duint_increment(resultp1,resultp2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
if (inexact) {
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
}
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Double Floating-point to Single Unsigned Fixed
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
dbl_to_sgl_fcnvfu (dbl_floating_point * srcptr, unsigned int *nullptr,
|
|
unsigned int *dstptr, unsigned int *status)
|
|
{
|
|
register unsigned int srcp1, srcp2, result;
|
|
register int src_exponent;
|
|
register boolean inexact = FALSE;
|
|
|
|
Dbl_copyfromptr(srcptr,srcp1,srcp2);
|
|
src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
|
|
|
|
/*
|
|
* Test for overflow
|
|
*/
|
|
if (src_exponent > SGL_FX_MAX_EXP + 1) {
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
result = 0;
|
|
} else {
|
|
result = 0xffffffff;
|
|
}
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* Generate result
|
|
*/
|
|
if (src_exponent >= 0) {
|
|
/*
|
|
* Check sign.
|
|
* If negative, trap unimplemented.
|
|
*/
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
Dbl_clear_signexponent_set_hidden(srcp1);
|
|
Suint_from_dbl_mantissa(srcp1,srcp2,src_exponent,result);
|
|
|
|
/* check for inexact */
|
|
if (Dbl_isinexact_to_unsigned(srcp1,srcp2,src_exponent)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
result++;
|
|
break;
|
|
case ROUNDMINUS: /* never negative */
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if(Dbl_isone_roundbit(srcp1,srcp2,src_exponent) &&
|
|
(Dbl_isone_stickybit(srcp1,srcp2,src_exponent)||
|
|
result&1))
|
|
result++;
|
|
break;
|
|
}
|
|
/* check for overflow */
|
|
if (result == 0) {
|
|
result = 0xffffffff;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
}
|
|
} else {
|
|
result = 0;
|
|
|
|
/* check for inexact */
|
|
if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
if (Dbl_iszero_sign(srcp1)) result++;
|
|
break;
|
|
case ROUNDMINUS:
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (src_exponent == -1 &&
|
|
Dbl_isnotzero_mantissa(srcp1,srcp2))
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
result = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
else result++;
|
|
}
|
|
}
|
|
}
|
|
*dstptr = result;
|
|
if (inexact) {
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
}
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Double Floating-point to Double Unsigned Fixed
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
dbl_to_dbl_fcnvfu (dbl_floating_point * srcptr, unsigned int *nullptr,
|
|
dbl_unsigned * dstptr, unsigned int *status)
|
|
{
|
|
register int src_exponent;
|
|
register unsigned int srcp1, srcp2, resultp1, resultp2;
|
|
register boolean inexact = FALSE;
|
|
|
|
Dbl_copyfromptr(srcptr,srcp1,srcp2);
|
|
src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
|
|
|
|
/*
|
|
* Test for overflow
|
|
*/
|
|
if (src_exponent > DBL_FX_MAX_EXP + 1) {
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
resultp1 = resultp2 = 0;
|
|
} else {
|
|
resultp1 = resultp2 = 0xffffffff;
|
|
}
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Generate result
|
|
*/
|
|
if (src_exponent >= 0) {
|
|
/*
|
|
* Check sign.
|
|
* If negative, trap unimplemented.
|
|
*/
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
resultp1 = resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
Dbl_clear_signexponent_set_hidden(srcp1);
|
|
Duint_from_dbl_mantissa(srcp1,srcp2,src_exponent,resultp1,
|
|
resultp2);
|
|
|
|
/* check for inexact */
|
|
if (Dbl_isinexact_to_unsigned(srcp1,srcp2,src_exponent)) {
|
|
inexact = TRUE;
|
|
/* round result */
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
Duint_increment(resultp1,resultp2);
|
|
break;
|
|
case ROUNDMINUS: /* never negative */
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if(Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
|
|
if(Dbl_isone_stickybit(srcp1,srcp2,src_exponent) ||
|
|
Duint_isone_lowp2(resultp2))
|
|
Duint_increment(resultp1,resultp2);
|
|
}
|
|
}
|
|
} else {
|
|
Duint_setzero(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)) {
|
|
Duint_increment(resultp1,resultp2);
|
|
}
|
|
break;
|
|
case ROUNDMINUS:
|
|
if (Dbl_isone_sign(srcp1)) {
|
|
resultp1 = resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (src_exponent == -1 &&
|
|
Dbl_isnotzero_mantissa(srcp1,srcp2))
|
|
if (Dbl_iszero_sign(srcp1)) {
|
|
Duint_increment(resultp1,resultp2);
|
|
} else {
|
|
resultp1 = 0;
|
|
resultp2 = 0;
|
|
if (Is_invalidtrap_enabled()) {
|
|
return(INVALIDEXCEPTION);
|
|
}
|
|
Set_invalidflag();
|
|
inexact = FALSE;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
Duint_copytoptr(resultp1,resultp2,dstptr);
|
|
if (inexact) {
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
}
|
|
return(NOEXCEPTION);
|
|
}
|
|
|