2019-05-24 12:04:10 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
2005-04-16 15:20:36 -07:00
/*
* Linux / PA - RISC Project ( http : //www.parisc-linux.org/)
*
* Floating - point emulation code
* Copyright ( C ) 2001 Hewlett - Packard ( Paul Bame ) < bame @ debian . org >
*/
/*
* BEGIN_DESC
*
* File :
* @ ( # ) pa / spmath / fcnvfx . c $ Revision : 1.1 $
*
* Purpose :
* Single Floating - point to Single Fixed - point
* Single Floating - point to Double Fixed - point
* Double Floating - point to Single Fixed - point
* Double Floating - point to Double Fixed - point
*
* External Interfaces :
* dbl_to_dbl_fcnvfx ( srcptr , nullptr , dstptr , status )
* dbl_to_sgl_fcnvfx ( srcptr , nullptr , dstptr , status )
* sgl_to_dbl_fcnvfx ( srcptr , nullptr , dstptr , status )
* sgl_to_sgl_fcnvfx ( 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"
/*
* Single Floating - point to Single Fixed - point
*/
/*ARGSUSED*/
int
sgl_to_sgl_fcnvfx (
sgl_floating_point * srcptr ,
sgl_floating_point * nullptr ,
int * dstptr ,
sgl_floating_point * status )
{
register unsigned int src , temp ;
register int src_exponent , result ;
register boolean inexact = FALSE ;
src = * srcptr ;
src_exponent = Sgl_exponent ( src ) - SGL_BIAS ;
/*
* Test for overflow
*/
if ( src_exponent > SGL_FX_MAX_EXP ) {
/* check for MININT */
if ( ( src_exponent > SGL_FX_MAX_EXP + 1 ) | |
Sgl_isnotzero_mantissa ( src ) | | Sgl_iszero_sign ( src ) ) {
if ( Sgl_iszero_sign ( src ) ) result = 0x7fffffff ;
else result = 0x80000000 ;
if ( Is_invalidtrap_enabled ( ) ) {
return ( INVALIDEXCEPTION ) ;
}
Set_invalidflag ( ) ;
* dstptr = result ;
return ( NOEXCEPTION ) ;
}
}
/*
* Generate result
*/
if ( src_exponent > = 0 ) {
temp = src ;
Sgl_clear_signexponent_set_hidden ( temp ) ;
Int_from_sgl_mantissa ( temp , src_exponent ) ;
if ( Sgl_isone_sign ( src ) ) result = - Sgl_all ( temp ) ;
else result = Sgl_all ( temp ) ;
/* 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 ) ) result + + ;
break ;
case ROUNDMINUS :
if ( Sgl_isone_sign ( src ) ) result - - ;
break ;
case ROUNDNEAREST :
if ( Sgl_isone_roundbit ( src , src_exponent ) ) {
if ( Sgl_isone_stickybit ( src , src_exponent )
| | ( Sgl_isone_lowmantissa ( temp ) ) )
if ( Sgl_iszero_sign ( src ) ) result + + ;
else result - - ;
}
}
}
}
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 - - ;
break ;
case ROUNDNEAREST :
if ( src_exponent = = - 1 )
if ( Sgl_isnotzero_mantissa ( src ) )
if ( Sgl_iszero_sign ( src ) ) result + + ;
else result - - ;
}
}
}
* dstptr = result ;
if ( inexact ) {
if ( Is_inexacttrap_enabled ( ) ) return ( INEXACTEXCEPTION ) ;
else Set_inexactflag ( ) ;
}
return ( NOEXCEPTION ) ;
}
/*
* Single Floating - point to Double Fixed - point
*/
/*ARGSUSED*/
int
sgl_to_dbl_fcnvfx (
sgl_floating_point * srcptr ,
unsigned int * nullptr ,
dbl_integer * dstptr ,
unsigned int * status )
{
register int src_exponent , resultp1 ;
register unsigned int src , temp , resultp2 ;
register boolean inexact = FALSE ;
src = * srcptr ;
src_exponent = Sgl_exponent ( src ) - SGL_BIAS ;
/*
* Test for overflow
*/
if ( src_exponent > DBL_FX_MAX_EXP ) {
/* check for MININT */
if ( ( src_exponent > DBL_FX_MAX_EXP + 1 ) | |
Sgl_isnotzero_mantissa ( src ) | | Sgl_iszero_sign ( src ) ) {
if ( Sgl_iszero_sign ( src ) ) {
resultp1 = 0x7fffffff ;
resultp2 = 0xffffffff ;
}
else {
resultp1 = 0x80000000 ;
resultp2 = 0 ;
}
if ( Is_invalidtrap_enabled ( ) ) {
return ( INVALIDEXCEPTION ) ;
}
Set_invalidflag ( ) ;
Dint_copytoptr ( resultp1 , resultp2 , dstptr ) ;
return ( NOEXCEPTION ) ;
}
Dint_set_minint ( resultp1 , resultp2 ) ;
Dint_copytoptr ( resultp1 , resultp2 , dstptr ) ;
return ( NOEXCEPTION ) ;
}
/*
* Generate result
*/
if ( src_exponent > = 0 ) {
temp = src ;
Sgl_clear_signexponent_set_hidden ( temp ) ;
Dint_from_sgl_mantissa ( temp , src_exponent , resultp1 , resultp2 ) ;
if ( Sgl_isone_sign ( src ) ) {
Dint_setone_sign ( resultp1 , resultp2 ) ;
}
/* 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 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDMINUS :
if ( Sgl_isone_sign ( src ) ) {
Dint_decrement ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDNEAREST :
if ( Sgl_isone_roundbit ( src , src_exponent ) )
if ( Sgl_isone_stickybit ( src , src_exponent ) | |
( Dint_isone_lowp2 ( resultp2 ) ) )
if ( Sgl_iszero_sign ( src ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
else {
Dint_decrement ( resultp1 , resultp2 ) ;
}
}
}
}
else {
Dint_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 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDMINUS :
if ( Sgl_isone_sign ( src ) ) {
Dint_decrement ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDNEAREST :
if ( src_exponent = = - 1 )
if ( Sgl_isnotzero_mantissa ( src ) )
if ( Sgl_iszero_sign ( src ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
else {
Dint_decrement ( resultp1 , resultp2 ) ;
}
}
}
}
Dint_copytoptr ( resultp1 , resultp2 , dstptr ) ;
if ( inexact ) {
if ( Is_inexacttrap_enabled ( ) ) return ( INEXACTEXCEPTION ) ;
else Set_inexactflag ( ) ;
}
return ( NOEXCEPTION ) ;
}
/*
* Double Floating - point to Single Fixed - point
*/
/*ARGSUSED*/
int
dbl_to_sgl_fcnvfx (
dbl_floating_point * srcptr ,
unsigned int * nullptr ,
int * dstptr ,
unsigned int * status )
{
register unsigned int srcp1 , srcp2 , tempp1 , tempp2 ;
register int src_exponent , result ;
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 ) {
/* check for MININT */
if ( Dbl_isoverflow_to_int ( src_exponent , srcp1 , srcp2 ) ) {
if ( Dbl_iszero_sign ( srcp1 ) ) result = 0x7fffffff ;
else result = 0x80000000 ;
if ( Is_invalidtrap_enabled ( ) ) {
return ( INVALIDEXCEPTION ) ;
}
Set_invalidflag ( ) ;
* dstptr = result ;
return ( NOEXCEPTION ) ;
}
}
/*
* Generate result
*/
if ( src_exponent > = 0 ) {
tempp1 = srcp1 ;
tempp2 = srcp2 ;
Dbl_clear_signexponent_set_hidden ( tempp1 ) ;
Int_from_dbl_mantissa ( tempp1 , tempp2 , src_exponent ) ;
if ( Dbl_isone_sign ( srcp1 ) & & ( src_exponent < = SGL_FX_MAX_EXP ) )
result = - Dbl_allp1 ( tempp1 ) ;
else result = Dbl_allp1 ( tempp1 ) ;
/* 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 ) ) result + + ;
break ;
case ROUNDMINUS :
if ( Dbl_isone_sign ( srcp1 ) ) result - - ;
break ;
case ROUNDNEAREST :
if ( Dbl_isone_roundbit ( srcp1 , srcp2 , src_exponent ) )
if ( Dbl_isone_stickybit ( srcp1 , srcp2 , src_exponent ) | |
( Dbl_isone_lowmantissap1 ( tempp1 ) ) )
if ( Dbl_iszero_sign ( srcp1 ) ) result + + ;
else result - - ;
}
/* check for overflow */
if ( ( Dbl_iszero_sign ( srcp1 ) & & result < 0 ) | |
( Dbl_isone_sign ( srcp1 ) & & result > 0 ) ) {
if ( Dbl_iszero_sign ( srcp1 ) ) result = 0x7fffffff ;
else result = 0x80000000 ;
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 - - ;
break ;
case ROUNDNEAREST :
if ( src_exponent = = - 1 )
if ( Dbl_isnotzero_mantissa ( srcp1 , srcp2 ) )
if ( Dbl_iszero_sign ( srcp1 ) ) result + + ;
else result - - ;
}
}
}
* dstptr = result ;
if ( inexact ) {
if ( Is_inexacttrap_enabled ( ) ) return ( INEXACTEXCEPTION ) ;
else Set_inexactflag ( ) ;
}
return ( NOEXCEPTION ) ;
}
/*
* Double Floating - point to Double Fixed - point
*/
/*ARGSUSED*/
int
dbl_to_dbl_fcnvfx (
dbl_floating_point * srcptr ,
unsigned int * nullptr ,
dbl_integer * dstptr ,
unsigned int * status )
{
register int src_exponent , resultp1 ;
register unsigned int srcp1 , srcp2 , tempp1 , tempp2 , 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 ) {
/* check for MININT */
if ( ( src_exponent > DBL_FX_MAX_EXP + 1 ) | |
Dbl_isnotzero_mantissa ( srcp1 , srcp2 ) | | Dbl_iszero_sign ( srcp1 ) ) {
if ( Dbl_iszero_sign ( srcp1 ) ) {
resultp1 = 0x7fffffff ;
resultp2 = 0xffffffff ;
}
else {
resultp1 = 0x80000000 ;
resultp2 = 0 ;
}
if ( Is_invalidtrap_enabled ( ) ) {
return ( INVALIDEXCEPTION ) ;
}
Set_invalidflag ( ) ;
Dint_copytoptr ( resultp1 , resultp2 , dstptr ) ;
return ( NOEXCEPTION ) ;
}
}
/*
* Generate result
*/
if ( src_exponent > = 0 ) {
tempp1 = srcp1 ;
tempp2 = srcp2 ;
Dbl_clear_signexponent_set_hidden ( tempp1 ) ;
Dint_from_dbl_mantissa ( tempp1 , tempp2 , src_exponent , resultp1 ,
resultp2 ) ;
if ( Dbl_isone_sign ( srcp1 ) ) {
Dint_setone_sign ( resultp1 , resultp2 ) ;
}
/* 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 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDMINUS :
if ( Dbl_isone_sign ( srcp1 ) ) {
Dint_decrement ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDNEAREST :
if ( Dbl_isone_roundbit ( srcp1 , srcp2 , src_exponent ) )
if ( Dbl_isone_stickybit ( srcp1 , srcp2 , src_exponent ) | |
( Dint_isone_lowp2 ( resultp2 ) ) )
if ( Dbl_iszero_sign ( srcp1 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
else {
Dint_decrement ( resultp1 , resultp2 ) ;
}
}
}
}
else {
Dint_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 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDMINUS :
if ( Dbl_isone_sign ( srcp1 ) ) {
Dint_decrement ( resultp1 , resultp2 ) ;
}
break ;
case ROUNDNEAREST :
if ( src_exponent = = - 1 )
if ( Dbl_isnotzero_mantissa ( srcp1 , srcp2 ) )
if ( Dbl_iszero_sign ( srcp1 ) ) {
Dint_increment ( resultp1 , resultp2 ) ;
}
else {
Dint_decrement ( resultp1 , resultp2 ) ;
}
}
}
}
Dint_copytoptr ( resultp1 , resultp2 , dstptr ) ;
if ( inexact ) {
if ( Is_inexacttrap_enabled ( ) ) return ( INEXACTEXCEPTION ) ;
else Set_inexactflag ( ) ;
}
return ( NOEXCEPTION ) ;
}