// This is adapted from a benchmark written by John Ellis and Pete Kovac
// of Post Communications.
// It was modified by Hans Boehm of Silicon Graphics.
// Translated to C++ 30 May 1997 by William D Clinger of Northeastern Univ.
// Translated to C 15 March 2000 by Hans Boehm, now at HP Labs.
//
//      This is no substitute for real applications.  No actual application
//      is likely to behave in exactly this way.  However, this benchmark was
//      designed to be more representative of real applications than other
//      Java GC benchmarks of which we are aware.
//      It attempts to model those properties of allocation requests that
//      are important to current GC techniques.
//      It is designed to be used either to obtain a single overall performance
//      number, or to give a more detailed estimate of how collector
//      performance varies with object lifetimes.  It prints the time
//      required to allocate and collect balanced binary trees of various
//      sizes.  Smaller trees result in shorter object lifetimes.  Each cycle
//      allocates roughly the same amount of memory.
//      Two data structures are kept around during the entire process, so
//      that the measured performance is representative of applications
//      that maintain some live in-memory data.  One of these is a tree
//      containing many pointers.  The other is a large array containing
//      double precision floating point numbers.  Both should be of comparable
//      size.
//
//      The results are only really meaningful together with a specification
//      of how much memory was used.  It is possible to trade memory for
//      better time performance.  This benchmark should be run in a 32 MB
//      heap, though we don't currently know how to enforce that uniformly.
//
//      Unlike the original Ellis and Kovac benchmark, we do not attempt
//      measure pause times.  This facility should eventually be added back
//      in.  There are several reasons for omitting it for now.  The original
//      implementation depended on assumptions about the thread scheduler
//      that don't hold uniformly.  The results really measure both the
//      scheduler and GC.  Pause time measurements tend to not fit well with
//      current benchmark suites.  As far as we know, none of the current
//      commercial Java implementations seriously attempt to minimize GC pause
//      times.

#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include "rl.h"

#ifdef GC
#  include "gc.h"
#endif

#ifdef PROFIL
extern void init_profiling();
  extern dump_profile();
#endif

//  These macros were a quick hack for the Macintosh.
//
//  #define currentTime() clock()
//  #define elapsedTime(x) ((1000*(x))/CLOCKS_PER_SEC)

#define currentTime() stats_rtclock()
#define elapsedTime(x) (x)

/* Get the current time in milliseconds */

unsigned
stats_rtclock( void )
{
    struct timeval t;
    struct timezone tz;

    if (gettimeofday( &t, &tz ) == -1)
        return 0;
    return (t.tv_sec * 1000 + t.tv_usec / 1000);
}

static const int kStretchTreeDepth    = 18;      // about 16Mb
static const int kLongLivedTreeDepth  = 16;  // about 4Mb
static const int kArraySize  = 500000;  // about 4Mb
static const int kMinTreeDepth = 4;
static const int kMaxTreeDepth = 16;

typedef struct Node0_struct {
    Rl left;
    Rl right;
    int i, j;
} Node0;

typedef Rl* Node;
#define TO_NODE(rl) ((Node0*) (rl)->ref)

#ifdef DEBUG
int allocated = 0;
int freed = 0;
#endif

void init_Node(Node me, Node l, Node r) {
    Node0* node = TO_NODE(me);
    rl_set(&node->left, me->ref, l);
    rl_set(&node->right, me->ref, r);
}

void destroy_Node(void* me) {
#ifdef DEBUG
    freed++;
#endif
    Node0* node = (Node0*)me;
    if(node->left.ref)
        rl_free(&node->left);
    if(node->right.ref)
        rl_free(&node->right);
}

// Nodes used by a tree of a given size
static int TreeSize(int i) {
    return ((1 << (i + 1)) - 1);
}

// Number of iterations to use for a given tree depth
static int NumIters(int i) {
    return 2 * TreeSize(kStretchTreeDepth) / TreeSize(i);
}

// Build tree top down, assigning to older objects.
static void Populate(int iDepth, Node thisNode) {
    Node0* node = TO_NODE(thisNode);
    if (iDepth<=0) {
        node->left.ref = NULL;
        node->right.ref = NULL;
        return;
    } else {
        iDepth--;
        rl_alloc(&node->left, node, sizeof(Node0), destroy_Node);
        rl_alloc(&node->right, node, sizeof(Node0), destroy_Node);
#ifdef DEBUG
        allocated+=2;
#endif
        Populate (iDepth, &node->left);
        Populate (iDepth, &node->right);
    }
}

// Build tree bottom-up
static void MakeTree(Node result, int iDepth) {
    if (iDepth<=0) {
        rl_alloc(result, NULL, sizeof(Node0), destroy_Node);
#ifdef DEBUG
        allocated++;
#endif
        Node0* node = TO_NODE(result);
        node->left.ref = NULL;
        node->right.ref = NULL;
        /* result is implicitly initialized in both cases. */
    } else {
        Rl left, right;
        MakeTree(&left, iDepth-1);
        MakeTree(&right, iDepth-1);
        rl_alloc(result, NULL, sizeof(Node0), destroy_Node);
#ifdef DEBUG
        allocated++;
#endif
        init_Node(result, &left, &right);
        rl_free(&left);
        rl_free(&right);
    }
}

static void PrintDiagnostics() {
#if 0
    long lFreeMemory = Runtime.getRuntime().freeMemory();
        long lTotalMemory = Runtime.getRuntime().totalMemory();

        System.out.print(" Total memory available="
                         + lTotalMemory + " bytes");
        System.out.println("  Free memory=" + lFreeMemory + " bytes");
#endif
}

static void TimeConstruction(int depth) {
    long    tStart, tFinish;
    int     iNumIters = NumIters(depth);
    Rl    tempTree;
    int 	i;

    printf("Creating %d trees of depth %d\n", iNumIters, depth);

    tStart = currentTime();
    for (i = 0; i < iNumIters; ++i) {
        rl_alloc(&tempTree, NULL, sizeof(Node0), destroy_Node);
        Populate(depth, &tempTree);
        rl_free(&tempTree);
    }
    tFinish = currentTime();
    printf("\tTop down construction took %d msec\n",
           elapsedTime(tFinish - tStart));

    tStart = currentTime();
    for (i = 0; i < iNumIters; ++i) {
        MakeTree(&tempTree, depth);
        rl_free(&tempTree);
    }
    tFinish = currentTime();
    printf("\tBottom up construction took %d msec\n",
           elapsedTime(tFinish - tStart));

}

int main() {
    Node    root;
    Rl    longLivedTree;
    Rl    tempTree;
    long    tStart, tFinish;
    long    tElapsed;
    int	i, d;
    double 	*array;

    printf("Garbage Collector Test\n");
    printf(" Live storage will peak at %d bytes.\n\n",
           2 * sizeof(Node0) * TreeSize(kLongLivedTreeDepth) +
           sizeof(double) * kArraySize);
    printf(" Stretching memory with a binary tree of depth %d\n",
           kStretchTreeDepth);
    PrintDiagnostics();
#	ifdef PROFIL
    init_profiling();
#	endif

    tStart = currentTime();

    // Stretch the memory space quickly
    MakeTree(&tempTree, kStretchTreeDepth);

#ifdef DEBUG
    printf("Made tree %i/%i\n", freed, allocated);
#endif
    rl_free(&tempTree);
#ifdef DEBUG
    printf("Deleted tree %i/%i\n", freed, allocated);
#endif

    // Create a long lived object
    printf(" Creating a long-lived binary tree of depth %d\n",
           kLongLivedTreeDepth);
    rl_alloc(&longLivedTree, NULL, sizeof(Node0), destroy_Node);
    Populate(kLongLivedTreeDepth, &longLivedTree);
#ifdef DEBUG
    printf("Populated tree %i/%i\n", freed, allocated);
#endif

    // Create long-lived array, filling half of it
    printf(" Creating a long-lived array of %d doubles\n", kArraySize);
    array = malloc(kArraySize * sizeof(double));
    for (i = 0; i < kArraySize/2; ++i) {
        array[i] = 1.0/i;
    }
    PrintDiagnostics();

    for (d = kMinTreeDepth; d <= kMaxTreeDepth; d += 2) {
        TimeConstruction(d);
    }
#ifdef DEBUG
    printf("Smol trees %i/%i\n", freed, allocated);
#endif

    if (longLivedTree.ref == 0 || array[1000] != 1.0/1000)
        fprintf(stderr, "Failed\n");
    // fake reference to LongLivedTree
    // and array
    // to keep them from being optimized away

    tFinish = currentTime();
    tElapsed = elapsedTime(tFinish-tStart);
    PrintDiagnostics();
    printf("Completed in %d msec\n", tElapsed);
#	ifdef PROFIL
    dump_profile();
#	endif
}