valter/dosbox-staging
1
0
Fork 0
Code Releases Activity

prevent overflows during cycles estimation

Browse source 
Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3257
This commit is contained in:
Sebastian Strohhäcker 2009-01-13 17:32:09 +00:00
parent a9f0ec5b10
commit 9690d8d53f
1 changed files with 7 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
src/dosbox.cpp
View file

@ -1,5 +1,5 @@
/*
* Copyright (C) 2002-2008 The DOSBox Team
* Copyright (C) 2002-2009 The DOSBox Team
*
* 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
@ -16,7 +16,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* $Id: dosbox.cpp,v 1.138 2008-10-27 11:02:41 c2woody Exp $ */
/* $Id: dosbox.cpp,v 1.139 2009-01-13 17:32:09 c2woody Exp $ */
#include <stdlib.h>
#include <stdarg.h>
@ -168,7 +168,7 @@ increaseticks:
if (CPU_CycleAutoAdjust && !CPU_SkipCycleAutoAdjust) {
if (ticksScheduled >= 250 || ticksDone >= 250 || (ticksAdded > 15 && ticksScheduled >= 5) ) {
/* ratio we are aiming for is around 90% usage*/
Bits ratio = (ticksScheduled * (CPU_CyclePercUsed*90*1024/100/100)) / ticksDone;
Bit32s ratio = (ticksScheduled * (CPU_CyclePercUsed*90*1024/100/100)) / ticksDone;
Bit32s new_cmax = CPU_CycleMax;
Bit64s cproc = (Bit64s)CPU_CycleMax * (Bit64s)ticksScheduled;
if (cproc > 0) {
@ -176,11 +176,12 @@ increaseticks:
to have smoother auto cycle adjustments */
double ratioremoved = (double) CPU_IODelayRemoved / (double) cproc;
if (ratioremoved < 1.0) {
ratio = (Bits)((double)ratio * (1 - ratioremoved));
Bit64s cmax_scaled = (Bit64s)CPU_CycleMax * (Bit64s)ratio;
ratio = (Bit32s)((double)ratio * (1 - ratioremoved));
if (ratio <= 1024)
new_cmax = (CPU_CycleMax * ratio) / 1024;
new_cmax = (Bit32s)(cmax_scaled / (Bit64s)1024);
else
new_cmax = 1 + (CPU_CycleMax >> 1) + (CPU_CycleMax * ratio) / 2048;
new_cmax = (Bit32s)(1 + (CPU_CycleMax >> 1) + cmax_scaled / (Bit64s)2048);
}
}