kolibrios-fun/programs/develop/open watcom/trunk/clib/intel/chipbug.c

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/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: verify Pentium processor divide bug
*
****************************************************************************/
#include "variety.h"
#include <rtinit.h>
#include "rtdata.h"
extern unsigned _WCNEAR __chipbug;
enum {
PROB_P5_DIV = 0x0001
};
_WCRTLINK void __verify_pentium_fdiv_bug()
{
/*
Verify we have got the Pentium FDIV problem.
The volatiles are to scare the optimizer away.
*/
volatile double num = 4195835;
volatile double denom = 3145727;
if( _RWD_real87 >= 3 ) {
if( (num - (num/denom)*denom) > 1.0e-8 ) {
__chipbug |= PROB_P5_DIV;
}
}
}
AXI( __verify_pentium_fdiv_bug, INIT_PRIORITY_FPU + 4 );