mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2024-12-29 09:13:38 +00:00
cf15984886
Starting in c23, this is a reserved keyword, so in the future, using it will start causing build failures: arch/parisc/math-emu/frnd.c:36:23: error: expected ';', ',' or ')' before 'nullptr' Since I can't think of a good replacement name, add a leading underscore to the function argument to avoid this namespace conflict. Apparently all of these arguments are unused. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Helge Deller <deller@gmx.de>
297 lines
8.5 KiB
C
297 lines
8.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* 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/fcnvff.c $Revision: 1.1 $
|
|
*
|
|
* Purpose:
|
|
* Single Floating-point to Double Floating-point
|
|
* Double Floating-point to Single Floating-point
|
|
*
|
|
* External Interfaces:
|
|
* dbl_to_sgl_fcnvff(srcptr,_nullptr,dstptr,status)
|
|
* sgl_to_dbl_fcnvff(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 Double Floating-point
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
sgl_to_dbl_fcnvff(
|
|
sgl_floating_point *srcptr,
|
|
unsigned int *_nullptr,
|
|
dbl_floating_point *dstptr,
|
|
unsigned int *status)
|
|
{
|
|
register unsigned int src, resultp1, resultp2;
|
|
register int src_exponent;
|
|
|
|
src = *srcptr;
|
|
src_exponent = Sgl_exponent(src);
|
|
Dbl_allp1(resultp1) = Sgl_all(src); /* set sign of result */
|
|
/*
|
|
* Test for NaN or infinity
|
|
*/
|
|
if (src_exponent == SGL_INFINITY_EXPONENT) {
|
|
/*
|
|
* determine if NaN or infinity
|
|
*/
|
|
if (Sgl_iszero_mantissa(src)) {
|
|
/*
|
|
* is infinity; want to return double infinity
|
|
*/
|
|
Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
else {
|
|
/*
|
|
* is NaN; signaling or quiet?
|
|
*/
|
|
if (Sgl_isone_signaling(src)) {
|
|
/* trap if INVALIDTRAP enabled */
|
|
if (Is_invalidtrap_enabled())
|
|
return(INVALIDEXCEPTION);
|
|
/* make NaN quiet */
|
|
else {
|
|
Set_invalidflag();
|
|
Sgl_set_quiet(src);
|
|
}
|
|
}
|
|
/*
|
|
* NaN is quiet, return as double NaN
|
|
*/
|
|
Dbl_setinfinity_exponent(resultp1);
|
|
Sgl_to_dbl_mantissa(src,resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
}
|
|
/*
|
|
* Test for zero or denormalized
|
|
*/
|
|
if (src_exponent == 0) {
|
|
/*
|
|
* determine if zero or denormalized
|
|
*/
|
|
if (Sgl_isnotzero_mantissa(src)) {
|
|
/*
|
|
* is denormalized; want to normalize
|
|
*/
|
|
Sgl_clear_signexponent(src);
|
|
Sgl_leftshiftby1(src);
|
|
Sgl_normalize(src,src_exponent);
|
|
Sgl_to_dbl_exponent(src_exponent,resultp1);
|
|
Sgl_to_dbl_mantissa(src,resultp1,resultp2);
|
|
}
|
|
else {
|
|
Dbl_setzero_exponentmantissa(resultp1,resultp2);
|
|
}
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* No special cases, just complete the conversion
|
|
*/
|
|
Sgl_to_dbl_exponent(src_exponent, resultp1);
|
|
Sgl_to_dbl_mantissa(Sgl_mantissa(src), resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Double Floating-point to Single Floating-point
|
|
*/
|
|
/*ARGSUSED*/
|
|
int
|
|
dbl_to_sgl_fcnvff(
|
|
dbl_floating_point *srcptr,
|
|
unsigned int *_nullptr,
|
|
sgl_floating_point *dstptr,
|
|
unsigned int *status)
|
|
{
|
|
register unsigned int srcp1, srcp2, result;
|
|
register int src_exponent, dest_exponent, dest_mantissa;
|
|
register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
|
|
register boolean lsb_odd = FALSE;
|
|
boolean is_tiny = FALSE;
|
|
|
|
Dbl_copyfromptr(srcptr,srcp1,srcp2);
|
|
src_exponent = Dbl_exponent(srcp1);
|
|
Sgl_all(result) = Dbl_allp1(srcp1); /* set sign of result */
|
|
/*
|
|
* Test for NaN or infinity
|
|
*/
|
|
if (src_exponent == DBL_INFINITY_EXPONENT) {
|
|
/*
|
|
* determine if NaN or infinity
|
|
*/
|
|
if (Dbl_iszero_mantissa(srcp1,srcp2)) {
|
|
/*
|
|
* is infinity; want to return single infinity
|
|
*/
|
|
Sgl_setinfinity_exponentmantissa(result);
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* is NaN; signaling or quiet?
|
|
*/
|
|
if (Dbl_isone_signaling(srcp1)) {
|
|
/* trap if INVALIDTRAP enabled */
|
|
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
|
|
else {
|
|
Set_invalidflag();
|
|
/* make NaN quiet */
|
|
Dbl_set_quiet(srcp1);
|
|
}
|
|
}
|
|
/*
|
|
* NaN is quiet, return as single NaN
|
|
*/
|
|
Sgl_setinfinity_exponent(result);
|
|
Sgl_set_mantissa(result,Dallp1(srcp1)<<3 | Dallp2(srcp2)>>29);
|
|
if (Sgl_iszero_mantissa(result)) Sgl_set_quiet(result);
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* Generate result
|
|
*/
|
|
Dbl_to_sgl_exponent(src_exponent,dest_exponent);
|
|
if (dest_exponent > 0) {
|
|
Dbl_to_sgl_mantissa(srcp1,srcp2,dest_mantissa,inexact,guardbit,
|
|
stickybit,lsb_odd);
|
|
}
|
|
else {
|
|
if (Dbl_iszero_exponentmantissa(srcp1,srcp2)){
|
|
Sgl_setzero_exponentmantissa(result);
|
|
*dstptr = result;
|
|
return(NOEXCEPTION);
|
|
}
|
|
if (Is_underflowtrap_enabled()) {
|
|
Dbl_to_sgl_mantissa(srcp1,srcp2,dest_mantissa,inexact,
|
|
guardbit,stickybit,lsb_odd);
|
|
}
|
|
else {
|
|
/* compute result, determine inexact info,
|
|
* and set Underflowflag if appropriate
|
|
*/
|
|
Dbl_to_sgl_denormalized(srcp1,srcp2,dest_exponent,
|
|
dest_mantissa,inexact,guardbit,stickybit,lsb_odd,
|
|
is_tiny);
|
|
}
|
|
}
|
|
/*
|
|
* Now round result if not exact
|
|
*/
|
|
if (inexact) {
|
|
switch (Rounding_mode()) {
|
|
case ROUNDPLUS:
|
|
if (Sgl_iszero_sign(result)) dest_mantissa++;
|
|
break;
|
|
case ROUNDMINUS:
|
|
if (Sgl_isone_sign(result)) dest_mantissa++;
|
|
break;
|
|
case ROUNDNEAREST:
|
|
if (guardbit) {
|
|
if (stickybit || lsb_odd) dest_mantissa++;
|
|
}
|
|
}
|
|
}
|
|
Sgl_set_exponentmantissa(result,dest_mantissa);
|
|
|
|
/*
|
|
* check for mantissa overflow after rounding
|
|
*/
|
|
if ((dest_exponent>0 || Is_underflowtrap_enabled()) &&
|
|
Sgl_isone_hidden(result)) dest_exponent++;
|
|
|
|
/*
|
|
* Test for overflow
|
|
*/
|
|
if (dest_exponent >= SGL_INFINITY_EXPONENT) {
|
|
/* trap if OVERFLOWTRAP enabled */
|
|
if (Is_overflowtrap_enabled()) {
|
|
/*
|
|
* Check for gross overflow
|
|
*/
|
|
if (dest_exponent >= SGL_INFINITY_EXPONENT+SGL_WRAP)
|
|
return(UNIMPLEMENTEDEXCEPTION);
|
|
|
|
/*
|
|
* Adjust bias of result
|
|
*/
|
|
Sgl_setwrapped_exponent(result,dest_exponent,ovfl);
|
|
*dstptr = result;
|
|
if (inexact)
|
|
if (Is_inexacttrap_enabled())
|
|
return(OVERFLOWEXCEPTION|INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
return(OVERFLOWEXCEPTION);
|
|
}
|
|
Set_overflowflag();
|
|
inexact = TRUE;
|
|
/* set result to infinity or largest number */
|
|
Sgl_setoverflow(result);
|
|
}
|
|
/*
|
|
* Test for underflow
|
|
*/
|
|
else if (dest_exponent <= 0) {
|
|
/* trap if UNDERFLOWTRAP enabled */
|
|
if (Is_underflowtrap_enabled()) {
|
|
/*
|
|
* Check for gross underflow
|
|
*/
|
|
if (dest_exponent <= -(SGL_WRAP))
|
|
return(UNIMPLEMENTEDEXCEPTION);
|
|
/*
|
|
* Adjust bias of result
|
|
*/
|
|
Sgl_setwrapped_exponent(result,dest_exponent,unfl);
|
|
*dstptr = result;
|
|
if (inexact)
|
|
if (Is_inexacttrap_enabled())
|
|
return(UNDERFLOWEXCEPTION|INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
return(UNDERFLOWEXCEPTION);
|
|
}
|
|
/*
|
|
* result is denormalized or signed zero
|
|
*/
|
|
if (inexact && is_tiny) Set_underflowflag();
|
|
|
|
}
|
|
else Sgl_set_exponent(result,dest_exponent);
|
|
*dstptr = result;
|
|
/*
|
|
* Trap if inexact trap is enabled
|
|
*/
|
|
if (inexact)
|
|
if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
|
|
else Set_inexactflag();
|
|
return(NOEXCEPTION);
|
|
}
|