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/* Test harness for the simple garbage collectors */
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <math.h>
extern int init_heap(int hsize);
enum block_kind { RAWDATA = 0, PTRDATA = 1, CLOSURE = 2 };
struct rootblock {
struct rootblock * next;
int numroots;
void * root[8];
};
extern void * alloc_block(struct rootblock * roots,
enum block_kind kind,
int size);
#ifdef DEBUG
extern void check_heap(void);
#endif
void gc_alarm(int live)
{
if (live == -1)
printf("<GC...>\n");
else
printf("<GC...%d bytes live>\n", live);
#ifdef DEBUG
check_heap();
#endif
}
/* Test with binary trees */
typedef struct {
long i;
} boxedInt;
boxedInt * BoxInt(struct rootblock * r, long n)
{
boxedInt * new = (boxedInt *) alloc_block(r, RAWDATA, sizeof(long));
new->i = n;
return new;
}
typedef struct tn {
struct tn* left;
struct tn* right;
boxedInt * item;
} treeNode;
treeNode* NewTreeNode(struct rootblock * r,
treeNode* left, treeNode* right, long item)
{
struct rootblock nr;
treeNode* new;
boxedInt* bitem;
nr.next = r; nr.numroots = 2; nr.root[0] = left; nr.root[1] = right;
bitem = BoxInt(&nr, item);
nr.numroots = 3; nr.root[2] = bitem;
new = (treeNode*) alloc_block(&nr, PTRDATA, sizeof(treeNode));
new->left = (treeNode *) nr.root[0];
new->right = (treeNode *) nr.root[1];
new->item = (boxedInt *) nr.root[2];
return new;
}
long ItemCheck(treeNode* tree)
{
if (tree->left == NULL)
return tree->item->i;
else
return tree->item->i + ItemCheck(tree->left) - ItemCheck(tree->right);
}
treeNode* BottomUpTree(struct rootblock * r, long item, unsigned depth)
{
struct rootblock nr;
if (depth > 0) {
nr.next = r; nr.numroots = 0;
nr.root[0] = BottomUpTree(&nr, 2 * item - 1, depth - 1);
nr.numroots = 1;
nr.root[1] = BottomUpTree(&nr, 2 * item, depth - 1);
nr.numroots = 2;
return NewTreeNode(&nr,
(treeNode *) nr.root[0],
(treeNode *) nr.root[1],
item);
} else {
return NewTreeNode(r, NULL, NULL, item);
}
}
treeNode* SkinnyTree(struct rootblock * r, unsigned depth)
{
struct rootblock nr;
if (depth > 0) {
nr.next = r; nr.numroots = 0;
nr.root[0] = SkinnyTree(&nr, depth - 1);
nr.numroots = 1;
return NewTreeNode(&nr,
(treeNode *) nr.root[0],
(treeNode *) nr.root[0],
depth);
} else {
return NULL;
}
}
void test(unsigned N)
{
unsigned depth, minDepth, maxDepth, stretchDepth;
struct rootblock r;
minDepth = 4;
if ((minDepth + 2) > N)
maxDepth = minDepth + 2;
else
maxDepth = N;
stretchDepth = maxDepth + 1;
r.next = NULL; r.numroots = 0;
r.root[0] = BottomUpTree(&r, 0, stretchDepth);
printf
(
"stretch tree of depth %u\t check: %li\n",
stretchDepth,
ItemCheck(r.root[0])
);
r.root[0] = SkinnyTree(&r, stretchDepth);
r.root[0] = BottomUpTree(&r, 0, maxDepth);
r.numroots = 1;
r.root[1] = SkinnyTree(&r, stretchDepth);
r.numroots = 2;
for (depth = minDepth; depth <= maxDepth; depth += 2) {
long i, iterations, check;
iterations = pow(2, maxDepth - depth + minDepth);
check = 0;
for (i = 1; i <= iterations; i++) {
r.root[2] = BottomUpTree(&r, i, depth);
check += ItemCheck(r.root[2]);
r.root[2] = BottomUpTree(&r, -i, depth);
check += ItemCheck(r.root[2]);
}
printf
(
"%li\t trees of depth %u\t check: %li\n",
iterations * 2,
depth,
check
);
}
printf
(
"long lived tree of depth %u\t check: %li\n",
maxDepth,
ItemCheck(r.root[0])
);
printf
(
"skinny tree of depth %u\t\t check: %li\n",
stretchDepth,
ItemCheck(r.root[1])
);
}
int main(int argc, char ** argv)
{
int N, heapsize;
N = argc > 1 ? atoi(argv[1]) : 16;
heapsize = argc > 2 ? atoi(argv[2]) : 8 * 1024 * 1024;
if (init_heap(heapsize) == -1) {
fprintf(stderr, "Failed to allocate heap.\n");
return 2;
}
test(N);
}
/*********************************
PROGRAM OUTPUT
==============
stretch tree of depth 17 check: -1
131072 trees of depth 4 check: -131072
32768 trees of depth 6 check: -32768
8192 trees of depth 8 check: -8192
2048 trees of depth 10 check: -2048
512 trees of depth 12 check: -512
128 trees of depth 14 check: -128
32 trees of depth 16 check: -32
long lived tree of depth 16 check: -1
***********************************/
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