// 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/fp/denormal.c                $ Revision: $
 *
 *  Purpose:
 *      <<please update with a synopsis of the functionality provided by this file>>
 *
 *  External Interfaces:
 *      <<the following list was autogenerated, please review>>
 *      dbl_denormalize(dbl_opndp1,dbl_opndp2,inexactflag,rmode)
 *      sgl_denormalize(sgl_opnd,inexactflag,rmode)
 *
 *  Internal Interfaces:
 *      <<please update>>
 *
 *  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 "hppa.h"
#include <linux/kernel.h>
/* #include <machine/sys/mdep_private.h> */

#undef Fpustatus_register
#define Fpustatus_register Fpu_register[0]

void
sgl_denormalize(unsigned int *sgl_opnd, boolean *inexactflag, int rmode)
{
        unsigned int opnd;
        int sign, exponent;
        boolean guardbit = FALSE, stickybit, inexact;

        opnd = *sgl_opnd;
        stickybit = *inexactflag;
        exponent = Sgl_exponent(opnd) - SGL_WRAP;
        sign = Sgl_sign(opnd);
        Sgl_denormalize(opnd,exponent,guardbit,stickybit,inexact);
        if (inexact) {
            switch (rmode) {
              case ROUNDPLUS:
                if (sign == 0) {
                        Sgl_increment(opnd);
                }
                break;
              case ROUNDMINUS:
                if (sign != 0) {
                        Sgl_increment(opnd);
                }
                break;
              case ROUNDNEAREST:
                if (guardbit && (stickybit || 
                       Sgl_isone_lowmantissa(opnd))) {
                           Sgl_increment(opnd);
                }
                break;
            }
        }
        Sgl_set_sign(opnd,sign);
        *sgl_opnd = opnd;
        *inexactflag = inexact;
        return;
}

void
dbl_denormalize(unsigned int *dbl_opndp1,
        unsigned int * dbl_opndp2,
        boolean *inexactflag,
        int rmode)
{
        unsigned int opndp1, opndp2;
        int sign, exponent;
        boolean guardbit = FALSE, stickybit, inexact;

        opndp1 = *dbl_opndp1;
        opndp2 = *dbl_opndp2;
        stickybit = *inexactflag;
        exponent = Dbl_exponent(opndp1) - DBL_WRAP;
        sign = Dbl_sign(opndp1);
        Dbl_denormalize(opndp1,opndp2,exponent,guardbit,stickybit,inexact);
        if (inexact) {
            switch (rmode) {
              case ROUNDPLUS:
                if (sign == 0) {
                        Dbl_increment(opndp1,opndp2);
                }
                break;
              case ROUNDMINUS:
                if (sign != 0) {
                        Dbl_increment(opndp1,opndp2);
                }
                break;
              case ROUNDNEAREST:
                if (guardbit && (stickybit || 
                       Dbl_isone_lowmantissap2(opndp2))) {
                           Dbl_increment(opndp1,opndp2);
                }
                break;
            }
        }
        Dbl_set_sign(opndp1,sign);
        *dbl_opndp1 = opndp1;
        *dbl_opndp2 = opndp2;
        *inexactflag = inexact;
        return;
}