/* $Id: bs3-timing-1-32.c32 89142 2021-05-18 14:33:03Z vboxsync $ */
/** @file
 * BS3Kit - bs3-timinig-1, 32-bit C code.
 */

/*
 * Copyright (C) 2007-2021 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 *
 * The contents of this file may alternatively be used under the terms
 * of the Common Development and Distribution License Version 1.0
 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
 * VirtualBox OSE distribution, in which case the provisions of the
 * CDDL are applicable instead of those of the GPL.
 *
 * You may elect to license modified versions of this file under the
 * terms and conditions of either the GPL or the CDDL or both.
 */


/*********************************************************************************************************************************
*   Header Files                                                                                                                 *
*********************************************************************************************************************************/
#include <bs3kit.h>
#include <iprt/asm-amd64-x86.h>
#include <iprt/asm-math.h>


static void bs3Timing1_Tsc_One(void)
{
    uint64_t const nsStart     = Bs3TestNow();
    uint64_t const uTscStart   = ASMReadTSC();
    uint64_t const nsDeadline  = nsStart + RT_NS_10SEC;
    uint64_t       cNsElapsed;
    uint64_t       cTicksElapsed;
    uint64_t       cTicksMin   = UINT64_MAX;
    uint64_t       cTicksMax   = 0;
    uint64_t       cTicksSum   = 0;
    uint64_t       cBelow512   = 0;
    uint64_t       cBelow1K    = 0;
    uint64_t       cBelow4K    = 0;
    uint64_t       cAbove512K  = 0;
    uint64_t       cAbove1M    = 0;
    uint64_t       cAbove10M   = 0;
    uint64_t       cTotalLoops = 0;

    /*
     * Test loop.
     */
    do
    {
        unsigned cLoops = 100000 + 1;
        cTotalLoops += cLoops - 1;
        while (--cLoops != 0)
        {
            uint64_t uTscPrev  = ASMReadTSC();
            uint64_t uTscNow   = ASMReadTSC();
            uint64_t cTicks    = uTscNow - uTscPrev;

            /* min/max/avg */
            cTicksSum += cTicks;
            if (cTicks < cTicksMin)
                cTicksMin = cTicks;
            if (cTicks > cTicksMax)
                cTicksMax = cTicks;

            /* range. */
            if (cTicks < _4K)
            {
                cBelow4K++;
                if (cTicks < _1K)
                {
                    cBelow1K++;
                    if (cTicks < 512)
                        cBelow512++;
                }
            }
            else if (cTicks >= _512K)
            {
                cAbove512K++;
                if (cTicks >= _1M)
                {
                    cAbove1M++;
                    if (cTicks >= 10*_1M)
                        cAbove10M++;
                }
            }
        }
    } while ((cNsElapsed = Bs3TestNow()) < nsDeadline);
    cTicksElapsed  = ASMReadTSC();
    cTicksElapsed -= uTscStart;
    cNsElapsed    -= nsStart;

    /*
     * Report results.
     *
     * Note! in 32-bit and 16-bit mode, values 4G or higher gets formatted as
     *       hexadecimal to avoid 64-bit division.
     */

    Bs3TestPrintf("%'14RU64 loops in %'RU64 ns / %'RU64 ticks\n", cTotalLoops, cNsElapsed, cTicksElapsed);

    /* Report results in ticks. */
    Bs3TestPrintf("average %RU64 ticks, min %'RU64, max %'RU64\n",
                  cTicksSum / cTotalLoops, cTicksMin, cTicksMax);
    Bs3TestPrintf("%'14RU64 below 512\n", cBelow512);
    Bs3TestPrintf("%'14RU64 below 1K\n", cBelow1K);
    Bs3TestPrintf("%'14RU64 below 4K\n", cBelow4K);
    Bs3TestPrintf("%'14RU64 inbetween\n", cTotalLoops - cBelow4K - cAbove512K);
    Bs3TestPrintf("%'14RU64 above 512K\n", cAbove512K);
    Bs3TestPrintf("%'14RU64 above 1M\n", cAbove1M);
    Bs3TestPrintf("%'14RU64 above 10M\n", cAbove10M);

    /* results in nanoseconds */
    if (cNsElapsed && cTicksElapsed)
    {
        /* Missing ??U8M and the assembly bugger. */
        //uint64_t const uFreq = ASMMultU64ByU32DivByU32(cTicksElapsed, RT_NS_1SEC, cNsElapsed);
        //uint64_t const uFreq = cTicksElapsed * (uint64_t)RT_NS_1SEC / cNsElapsed;
        uint64_t const uFreq = cTicksElapsed / cNsElapsed;
        Bs3TestPrintf("%RU64 Hz\n", uFreq);
    }
}

BS3_DECL(void) bs3Timing1_Tsc_pe32(void)
{
    Bs3TestPrintf("bs3Timing1_Tsc_pe32\n");
    bs3Timing1_Tsc_One();
}

/* P.S. don't forget: VBoxManage setextradata bs3-timing-1 VBoxInternal/Devices/VMMDev/0/Config/TestingEnabled 1 */