mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-13 09:46:53 +07:00
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!
298 lines
8.8 KiB
C
298 lines
8.8 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/dfrem.c $Revision: 1.1 $
|
|
*
|
|
* Purpose:
|
|
* Double Precision Floating-point Remainder
|
|
*
|
|
* External Interfaces:
|
|
* dbl_frem(srcptr1,srcptr2,dstptr,status)
|
|
*
|
|
* Internal Interfaces:
|
|
*
|
|
* Theory:
|
|
* <<please update with a overview of the operation of this file>>
|
|
*
|
|
* END_DESC
|
|
*/
|
|
|
|
|
|
|
|
#include "float.h"
|
|
#include "dbl_float.h"
|
|
|
|
/*
|
|
* Double Precision Floating-point Remainder
|
|
*/
|
|
|
|
int
|
|
dbl_frem (dbl_floating_point * srcptr1, dbl_floating_point * srcptr2,
|
|
dbl_floating_point * dstptr, unsigned int *status)
|
|
{
|
|
register unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2;
|
|
register unsigned int resultp1, resultp2;
|
|
register int opnd1_exponent, opnd2_exponent, dest_exponent, stepcount;
|
|
register boolean roundup = FALSE;
|
|
|
|
Dbl_copyfromptr(srcptr1,opnd1p1,opnd1p2);
|
|
Dbl_copyfromptr(srcptr2,opnd2p1,opnd2p2);
|
|
/*
|
|
* check first operand for NaN's or infinity
|
|
*/
|
|
if ((opnd1_exponent = Dbl_exponent(opnd1p1)) == DBL_INFINITY_EXPONENT) {
|
|
if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
|
|
if (Dbl_isnotnan(opnd2p1,opnd2p2)) {
|
|
/* invalid since first operand is infinity */
|
|
if (Is_invalidtrap_enabled())
|
|
return(INVALIDEXCEPTION);
|
|
Set_invalidflag();
|
|
Dbl_makequietnan(resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
}
|
|
else {
|
|
/*
|
|
* is NaN; signaling or quiet?
|
|
*/
|
|
if (Dbl_isone_signaling(opnd1p1)) {
|
|
/* trap if INVALIDTRAP enabled */
|
|
if (Is_invalidtrap_enabled())
|
|
return(INVALIDEXCEPTION);
|
|
/* make NaN quiet */
|
|
Set_invalidflag();
|
|
Dbl_set_quiet(opnd1p1);
|
|
}
|
|
/*
|
|
* is second operand a signaling NaN?
|
|
*/
|
|
else if (Dbl_is_signalingnan(opnd2p1)) {
|
|
/* trap if INVALIDTRAP enabled */
|
|
if (Is_invalidtrap_enabled())
|
|
return(INVALIDEXCEPTION);
|
|
/* make NaN quiet */
|
|
Set_invalidflag();
|
|
Dbl_set_quiet(opnd2p1);
|
|
Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* return quiet NaN
|
|
*/
|
|
Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
}
|
|
/*
|
|
* check second operand for NaN's or infinity
|
|
*/
|
|
if ((opnd2_exponent = Dbl_exponent(opnd2p1)) == DBL_INFINITY_EXPONENT) {
|
|
if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
|
|
/*
|
|
* return first operand
|
|
*/
|
|
Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* is NaN; signaling or quiet?
|
|
*/
|
|
if (Dbl_isone_signaling(opnd2p1)) {
|
|
/* trap if INVALIDTRAP enabled */
|
|
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
|
|
/* make NaN quiet */
|
|
Set_invalidflag();
|
|
Dbl_set_quiet(opnd2p1);
|
|
}
|
|
/*
|
|
* return quiet NaN
|
|
*/
|
|
Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/*
|
|
* check second operand for zero
|
|
*/
|
|
if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) {
|
|
/* invalid since second operand is zero */
|
|
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
|
|
Set_invalidflag();
|
|
Dbl_makequietnan(resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* get sign of result
|
|
*/
|
|
resultp1 = opnd1p1;
|
|
|
|
/*
|
|
* check for denormalized operands
|
|
*/
|
|
if (opnd1_exponent == 0) {
|
|
/* check for zero */
|
|
if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
|
|
Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
/* normalize, then continue */
|
|
opnd1_exponent = 1;
|
|
Dbl_normalize(opnd1p1,opnd1p2,opnd1_exponent);
|
|
}
|
|
else {
|
|
Dbl_clear_signexponent_set_hidden(opnd1p1);
|
|
}
|
|
if (opnd2_exponent == 0) {
|
|
/* normalize, then continue */
|
|
opnd2_exponent = 1;
|
|
Dbl_normalize(opnd2p1,opnd2p2,opnd2_exponent);
|
|
}
|
|
else {
|
|
Dbl_clear_signexponent_set_hidden(opnd2p1);
|
|
}
|
|
|
|
/* find result exponent and divide step loop count */
|
|
dest_exponent = opnd2_exponent - 1;
|
|
stepcount = opnd1_exponent - opnd2_exponent;
|
|
|
|
/*
|
|
* check for opnd1/opnd2 < 1
|
|
*/
|
|
if (stepcount < 0) {
|
|
/*
|
|
* check for opnd1/opnd2 > 1/2
|
|
*
|
|
* In this case n will round to 1, so
|
|
* r = opnd1 - opnd2
|
|
*/
|
|
if (stepcount == -1 &&
|
|
Dbl_isgreaterthan(opnd1p1,opnd1p2,opnd2p1,opnd2p2)) {
|
|
/* set sign */
|
|
Dbl_allp1(resultp1) = ~Dbl_allp1(resultp1);
|
|
/* align opnd2 with opnd1 */
|
|
Dbl_leftshiftby1(opnd2p1,opnd2p2);
|
|
Dbl_subtract(opnd2p1,opnd2p2,opnd1p1,opnd1p2,
|
|
opnd2p1,opnd2p2);
|
|
/* now normalize */
|
|
while (Dbl_iszero_hidden(opnd2p1)) {
|
|
Dbl_leftshiftby1(opnd2p1,opnd2p2);
|
|
dest_exponent--;
|
|
}
|
|
Dbl_set_exponentmantissa(resultp1,resultp2,opnd2p1,opnd2p2);
|
|
goto testforunderflow;
|
|
}
|
|
/*
|
|
* opnd1/opnd2 <= 1/2
|
|
*
|
|
* In this case n will round to zero, so
|
|
* r = opnd1
|
|
*/
|
|
Dbl_set_exponentmantissa(resultp1,resultp2,opnd1p1,opnd1p2);
|
|
dest_exponent = opnd1_exponent;
|
|
goto testforunderflow;
|
|
}
|
|
|
|
/*
|
|
* Generate result
|
|
*
|
|
* Do iterative subtract until remainder is less than operand 2.
|
|
*/
|
|
while (stepcount-- > 0 && (Dbl_allp1(opnd1p1) || Dbl_allp2(opnd1p2))) {
|
|
if (Dbl_isnotlessthan(opnd1p1,opnd1p2,opnd2p1,opnd2p2)) {
|
|
Dbl_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2,opnd1p1,opnd1p2);
|
|
}
|
|
Dbl_leftshiftby1(opnd1p1,opnd1p2);
|
|
}
|
|
/*
|
|
* Do last subtract, then determine which way to round if remainder
|
|
* is exactly 1/2 of opnd2
|
|
*/
|
|
if (Dbl_isnotlessthan(opnd1p1,opnd1p2,opnd2p1,opnd2p2)) {
|
|
Dbl_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2,opnd1p1,opnd1p2);
|
|
roundup = TRUE;
|
|
}
|
|
if (stepcount > 0 || Dbl_iszero(opnd1p1,opnd1p2)) {
|
|
/* division is exact, remainder is zero */
|
|
Dbl_setzero_exponentmantissa(resultp1,resultp2);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|
|
|
|
/*
|
|
* Check for cases where opnd1/opnd2 < n
|
|
*
|
|
* In this case the result's sign will be opposite that of
|
|
* opnd1. The mantissa also needs some correction.
|
|
*/
|
|
Dbl_leftshiftby1(opnd1p1,opnd1p2);
|
|
if (Dbl_isgreaterthan(opnd1p1,opnd1p2,opnd2p1,opnd2p2)) {
|
|
Dbl_invert_sign(resultp1);
|
|
Dbl_leftshiftby1(opnd2p1,opnd2p2);
|
|
Dbl_subtract(opnd2p1,opnd2p2,opnd1p1,opnd1p2,opnd1p1,opnd1p2);
|
|
}
|
|
/* check for remainder being exactly 1/2 of opnd2 */
|
|
else if (Dbl_isequal(opnd1p1,opnd1p2,opnd2p1,opnd2p2) && roundup) {
|
|
Dbl_invert_sign(resultp1);
|
|
}
|
|
|
|
/* normalize result's mantissa */
|
|
while (Dbl_iszero_hidden(opnd1p1)) {
|
|
dest_exponent--;
|
|
Dbl_leftshiftby1(opnd1p1,opnd1p2);
|
|
}
|
|
Dbl_set_exponentmantissa(resultp1,resultp2,opnd1p1,opnd1p2);
|
|
|
|
/*
|
|
* Test for underflow
|
|
*/
|
|
testforunderflow:
|
|
if (dest_exponent <= 0) {
|
|
/* trap if UNDERFLOWTRAP enabled */
|
|
if (Is_underflowtrap_enabled()) {
|
|
/*
|
|
* Adjust bias of result
|
|
*/
|
|
Dbl_setwrapped_exponent(resultp1,dest_exponent,unfl);
|
|
/* frem is always exact */
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(UNDERFLOWEXCEPTION);
|
|
}
|
|
/*
|
|
* denormalize result or set to signed zero
|
|
*/
|
|
if (dest_exponent >= (1 - DBL_P)) {
|
|
Dbl_rightshift_exponentmantissa(resultp1,resultp2,
|
|
1-dest_exponent);
|
|
}
|
|
else {
|
|
Dbl_setzero_exponentmantissa(resultp1,resultp2);
|
|
}
|
|
}
|
|
else Dbl_set_exponent(resultp1,dest_exponent);
|
|
Dbl_copytoptr(resultp1,resultp2,dstptr);
|
|
return(NOEXCEPTION);
|
|
}
|