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Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 42 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190524100845.259718220@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
297 lines
8.5 KiB
C
297 lines
8.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Linux/PA-RISC Project (http://www.parisc-linux.org/)
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*
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* Floating-point emulation code
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* Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
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*/
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/*
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* BEGIN_DESC
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*
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* File:
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* @(#) pa/spmath/fcnvff.c $Revision: 1.1 $
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*
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* Purpose:
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* Single Floating-point to Double Floating-point
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* Double Floating-point to Single Floating-point
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*
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* External Interfaces:
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* dbl_to_sgl_fcnvff(srcptr,nullptr,dstptr,status)
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* sgl_to_dbl_fcnvff(srcptr,nullptr,dstptr,status)
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*
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* Internal Interfaces:
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*
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* Theory:
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* <<please update with a overview of the operation of this file>>
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*
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* END_DESC
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*/
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#include "float.h"
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#include "sgl_float.h"
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#include "dbl_float.h"
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#include "cnv_float.h"
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/*
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* Single Floating-point to Double Floating-point
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*/
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/*ARGSUSED*/
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int
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sgl_to_dbl_fcnvff(
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sgl_floating_point *srcptr,
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unsigned int *nullptr,
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dbl_floating_point *dstptr,
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unsigned int *status)
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{
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register unsigned int src, resultp1, resultp2;
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register int src_exponent;
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src = *srcptr;
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src_exponent = Sgl_exponent(src);
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Dbl_allp1(resultp1) = Sgl_all(src); /* set sign of result */
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/*
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* Test for NaN or infinity
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*/
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if (src_exponent == SGL_INFINITY_EXPONENT) {
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/*
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* determine if NaN or infinity
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*/
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if (Sgl_iszero_mantissa(src)) {
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/*
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* is infinity; want to return double infinity
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*/
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Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
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Dbl_copytoptr(resultp1,resultp2,dstptr);
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return(NOEXCEPTION);
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}
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else {
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/*
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* is NaN; signaling or quiet?
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*/
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if (Sgl_isone_signaling(src)) {
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/* trap if INVALIDTRAP enabled */
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if (Is_invalidtrap_enabled())
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return(INVALIDEXCEPTION);
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/* make NaN quiet */
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else {
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Set_invalidflag();
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Sgl_set_quiet(src);
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}
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}
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/*
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* NaN is quiet, return as double NaN
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*/
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Dbl_setinfinity_exponent(resultp1);
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Sgl_to_dbl_mantissa(src,resultp1,resultp2);
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Dbl_copytoptr(resultp1,resultp2,dstptr);
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return(NOEXCEPTION);
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}
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}
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/*
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* Test for zero or denormalized
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*/
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if (src_exponent == 0) {
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/*
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* determine if zero or denormalized
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*/
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if (Sgl_isnotzero_mantissa(src)) {
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/*
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* is denormalized; want to normalize
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*/
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Sgl_clear_signexponent(src);
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Sgl_leftshiftby1(src);
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Sgl_normalize(src,src_exponent);
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Sgl_to_dbl_exponent(src_exponent,resultp1);
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Sgl_to_dbl_mantissa(src,resultp1,resultp2);
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}
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else {
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Dbl_setzero_exponentmantissa(resultp1,resultp2);
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}
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Dbl_copytoptr(resultp1,resultp2,dstptr);
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return(NOEXCEPTION);
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}
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/*
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* No special cases, just complete the conversion
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*/
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Sgl_to_dbl_exponent(src_exponent, resultp1);
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Sgl_to_dbl_mantissa(Sgl_mantissa(src), resultp1,resultp2);
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Dbl_copytoptr(resultp1,resultp2,dstptr);
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return(NOEXCEPTION);
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}
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/*
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* Double Floating-point to Single Floating-point
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*/
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/*ARGSUSED*/
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int
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dbl_to_sgl_fcnvff(
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dbl_floating_point *srcptr,
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unsigned int *nullptr,
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sgl_floating_point *dstptr,
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unsigned int *status)
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{
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register unsigned int srcp1, srcp2, result;
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register int src_exponent, dest_exponent, dest_mantissa;
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register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
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register boolean lsb_odd = FALSE;
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boolean is_tiny = FALSE;
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Dbl_copyfromptr(srcptr,srcp1,srcp2);
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src_exponent = Dbl_exponent(srcp1);
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Sgl_all(result) = Dbl_allp1(srcp1); /* set sign of result */
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/*
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* Test for NaN or infinity
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*/
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if (src_exponent == DBL_INFINITY_EXPONENT) {
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/*
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* determine if NaN or infinity
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*/
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if (Dbl_iszero_mantissa(srcp1,srcp2)) {
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/*
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* is infinity; want to return single infinity
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*/
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Sgl_setinfinity_exponentmantissa(result);
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*dstptr = result;
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return(NOEXCEPTION);
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}
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/*
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* is NaN; signaling or quiet?
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*/
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if (Dbl_isone_signaling(srcp1)) {
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/* trap if INVALIDTRAP enabled */
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if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
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else {
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Set_invalidflag();
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/* make NaN quiet */
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Dbl_set_quiet(srcp1);
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}
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}
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/*
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* NaN is quiet, return as single NaN
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*/
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Sgl_setinfinity_exponent(result);
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Sgl_set_mantissa(result,Dallp1(srcp1)<<3 | Dallp2(srcp2)>>29);
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if (Sgl_iszero_mantissa(result)) Sgl_set_quiet(result);
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*dstptr = result;
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return(NOEXCEPTION);
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}
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/*
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* Generate result
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*/
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Dbl_to_sgl_exponent(src_exponent,dest_exponent);
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if (dest_exponent > 0) {
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Dbl_to_sgl_mantissa(srcp1,srcp2,dest_mantissa,inexact,guardbit,
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stickybit,lsb_odd);
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}
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else {
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if (Dbl_iszero_exponentmantissa(srcp1,srcp2)){
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Sgl_setzero_exponentmantissa(result);
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*dstptr = result;
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return(NOEXCEPTION);
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}
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if (Is_underflowtrap_enabled()) {
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Dbl_to_sgl_mantissa(srcp1,srcp2,dest_mantissa,inexact,
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guardbit,stickybit,lsb_odd);
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}
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else {
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/* compute result, determine inexact info,
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* and set Underflowflag if appropriate
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*/
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Dbl_to_sgl_denormalized(srcp1,srcp2,dest_exponent,
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dest_mantissa,inexact,guardbit,stickybit,lsb_odd,
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is_tiny);
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}
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}
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/*
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* Now round result if not exact
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*/
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if (inexact) {
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switch (Rounding_mode()) {
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case ROUNDPLUS:
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if (Sgl_iszero_sign(result)) dest_mantissa++;
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break;
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case ROUNDMINUS:
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if (Sgl_isone_sign(result)) dest_mantissa++;
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break;
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case ROUNDNEAREST:
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if (guardbit) {
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if (stickybit || lsb_odd) dest_mantissa++;
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}
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}
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}
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Sgl_set_exponentmantissa(result,dest_mantissa);
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/*
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* check for mantissa overflow after rounding
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*/
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if ((dest_exponent>0 || Is_underflowtrap_enabled()) &&
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Sgl_isone_hidden(result)) dest_exponent++;
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/*
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* Test for overflow
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*/
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if (dest_exponent >= SGL_INFINITY_EXPONENT) {
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/* trap if OVERFLOWTRAP enabled */
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if (Is_overflowtrap_enabled()) {
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/*
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* Check for gross overflow
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*/
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if (dest_exponent >= SGL_INFINITY_EXPONENT+SGL_WRAP)
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return(UNIMPLEMENTEDEXCEPTION);
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/*
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* Adjust bias of result
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*/
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Sgl_setwrapped_exponent(result,dest_exponent,ovfl);
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*dstptr = result;
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if (inexact)
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if (Is_inexacttrap_enabled())
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return(OVERFLOWEXCEPTION|INEXACTEXCEPTION);
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else Set_inexactflag();
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return(OVERFLOWEXCEPTION);
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}
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Set_overflowflag();
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inexact = TRUE;
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/* set result to infinity or largest number */
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Sgl_setoverflow(result);
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}
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/*
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* Test for underflow
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*/
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else if (dest_exponent <= 0) {
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/* trap if UNDERFLOWTRAP enabled */
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if (Is_underflowtrap_enabled()) {
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/*
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* Check for gross underflow
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*/
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if (dest_exponent <= -(SGL_WRAP))
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return(UNIMPLEMENTEDEXCEPTION);
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/*
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* Adjust bias of result
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*/
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Sgl_setwrapped_exponent(result,dest_exponent,unfl);
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*dstptr = result;
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if (inexact)
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if (Is_inexacttrap_enabled())
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return(UNDERFLOWEXCEPTION|INEXACTEXCEPTION);
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else Set_inexactflag();
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return(UNDERFLOWEXCEPTION);
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}
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/*
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* result is denormalized or signed zero
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*/
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if (inexact && is_tiny) Set_underflowflag();
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}
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else Sgl_set_exponent(result,dest_exponent);
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*dstptr = result;
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/*
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* Trap if inexact trap is enabled
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*/
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if (inexact)
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if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
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else Set_inexactflag();
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return(NOEXCEPTION);
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}
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