/*

  This program is part of the TACLeBench benchmark suite.
  Version V 2.0

  Name: dijkstra

  Author: unknown

  Function: dijkstra finds the shortest path between nodes in a graph

  Source: network section of MiBench

  Changes: Made some variables local, compute checksum

  License: GPL

*/

#include "input.h"

/*
  Definitions of symbolic constants
*/

// Wasm loop bounds


#include "input.c"


__attribute__((import_module("__pragma"), import_name("loopbound"))) extern void
__pragma_loopbound(unsigned int min_bound, unsigned int max_bound);

#define NONE          9999
#define OUT_OF_MEMORY -1
#define QUEUE_SIZE    1000

/*
  Type declarations
*/
struct _NODE {
    int dist;
    int prev;
};

struct _QITEM {
    int node;
    int dist;
    int prev;
    struct _QITEM *next;
};

/*
  Global variable definitions
*/
struct _NODE dijkstra_rgnNodes[NUM_NODES];

int dijkstra_queueCount;
int dijkstra_queueNext;
struct _QITEM *dijkstra_queueHead;
struct _QITEM dijkstra_queueItems[QUEUE_SIZE];

int dijkstra_checksum = 0;

/*
  Forward declaration of functions
*/
__attribute__((always_inline)) static inline void dijkstra_init(void);
__attribute__((always_inline)) static inline int dijkstra_return(void);
__attribute__((always_inline)) static inline int
dijkstra_enqueue(int node, int dist, int prev);
__attribute__((always_inline)) static inline void
dijkstra_dequeue(int *node, int *dist, int *prev);
__attribute__((always_inline)) static inline int dijkstra_qcount(void);
__attribute__((always_inline)) static inline int dijkstra_find(int chStart,
                                                               int chEnd);
__attribute__((noinline)) __attribute__((export_name("entrypoint")))
__attribute__((noinline)) __attribute__((export_name("entrypoint"))) void
dijkstra_main(void);
__attribute__((noinline)) __attribute__((export_name("main")))
__attribute__((noinline)) __attribute__((export_name("main"))) int
main(void);

__attribute__((always_inline)) static inline void
dijkstra_init(void) {
    int i, k;
    volatile int x = 0;
    __pragma_loopbound(100, 100);
    for (i = 0; i < NUM_NODES; i++) {
        __pragma_loopbound(100, 100);
        for (k = 0; k < NUM_NODES; k++)
            dijkstra_AdjMatrix[i][k] ^= x;
    }

    dijkstra_queueCount = 0;
    dijkstra_queueNext = 0;
    dijkstra_queueHead = (struct _QITEM *) 0;

    dijkstra_checksum = 0;
}

__attribute__((always_inline)) static inline int
dijkstra_return(void) {
    return ((dijkstra_checksum == 25) ? 0 : -1);
}

__attribute__((always_inline)) static inline int
dijkstra_enqueue(int node, int dist, int prev) {
    struct _QITEM *newItem = &dijkstra_queueItems[dijkstra_queueNext];
    struct _QITEM *last = dijkstra_queueHead;

    if (++dijkstra_queueNext >= QUEUE_SIZE)
        return OUT_OF_MEMORY;
    newItem->node = node;
    newItem->dist = dist;
    newItem->prev = prev;
    newItem->next = 0;

    if (!last)
        dijkstra_queueHead = newItem;
    else {
        __pragma_loopbound(0, 1000);
        while (last->next)
            last = last->next;
        last->next = newItem;
    }
    dijkstra_queueCount++;
    return 0;
}

__attribute__((always_inline)) static inline void
dijkstra_dequeue(int *node, int *dist, int *prev) {
    if (dijkstra_queueHead) {
        *node = dijkstra_queueHead->node;
        *dist = dijkstra_queueHead->dist;
        *prev = dijkstra_queueHead->prev;
        dijkstra_queueHead = dijkstra_queueHead->next;
        dijkstra_queueCount--;
    }
}

__attribute__((always_inline)) static inline int
dijkstra_qcount(void) {
    return (dijkstra_queueCount);
}

__attribute__((always_inline)) static inline int
dijkstra_find(int chStart, int chEnd) {
    int ch;
    int prev, node = 0;
    int cost, dist = 0;
    int i;

    __pragma_loopbound(100, 100);
    for (ch = 0; ch < NUM_NODES; ch++) {
        dijkstra_rgnNodes[ch].dist = NONE;
        dijkstra_rgnNodes[ch].prev = NONE;
    }

    if (chStart == chEnd) {
    } else {
        dijkstra_rgnNodes[chStart].dist = 0;
        dijkstra_rgnNodes[chStart].prev = NONE;

        if (dijkstra_enqueue(chStart, 0, NONE) == OUT_OF_MEMORY)
            return OUT_OF_MEMORY;

        __pragma_loopbound(100, 1000);
        while (dijkstra_qcount() > 0) {
            dijkstra_dequeue(&node, &dist, &prev);
            __pragma_loopbound(100, 100);
            for (i = 0; i < NUM_NODES; i++) {
                if ((cost = dijkstra_AdjMatrix[node][i]) != NONE) {
                    if ((NONE == dijkstra_rgnNodes[i].dist) ||
                        (dijkstra_rgnNodes[i].dist > (cost + dist))) {
                        dijkstra_rgnNodes[i].dist = dist + cost;
                        dijkstra_rgnNodes[i].prev = node;
                        if (dijkstra_enqueue(i, dist + cost, node) ==
                            OUT_OF_MEMORY)
                            return OUT_OF_MEMORY;
                    }
                }
            }
        }
    }
    return 0;
}

__attribute__((noinline)) __attribute__((export_name("entrypoint")))
__attribute__((noinline)) __attribute__((export_name("entrypoint"))) void
dijkstra_main(void) {
    int i, j;

    /* finds 20 shortest paths between nodes */
    __pragma_loopbound(20, 20);
    for (i = 0, j = NUM_NODES / 2; i < 20; i++, j++) {
        j = j % NUM_NODES;
        if (dijkstra_find(i, j) == OUT_OF_MEMORY) {
            dijkstra_checksum += OUT_OF_MEMORY;
            return;
        } else
            dijkstra_checksum += dijkstra_rgnNodes[j].dist;
        dijkstra_queueNext = 0;
    }
}

__attribute__((noinline)) __attribute__((export_name("main")))
__attribute__((noinline)) __attribute__((export_name("main"))) int
main(void) {
    dijkstra_init();
    dijkstra_main();

    return (dijkstra_return());
}