1 files changed, 94 insertions, 0 deletions
diff --git a/src/tools/lcc/src/alloc.c b/src/tools/lcc/src/alloc.c
new file mode 100644
index 00000000..e0566dfd
--- /dev/null
+++ b/src/tools/lcc/src/alloc.c
@@ -0,0 +1,94 @@
+#include "c.h"
+struct block {
+	struct block *next;
+	char *limit;
+	char *avail;
+};
+union align {
+	long l;
+	char *p;
+	double d;
+	int (*f)(void);
+};
+union header {
+	struct block b;
+	union align a;
+};
+#ifdef PURIFY
+union header *arena[3];
+
+void *allocate(unsigned long n, unsigned a) {
+	union header *new = malloc(sizeof *new + n);
+
+	assert(a < NELEMS(arena));
+	if (new == NULL) {
+		error("insufficient memory\n");
+		exit(1);
+	}
+	new->b.next = (void *)arena[a];
+	arena[a] = new;
+	return new + 1;
+}
+
+void deallocate(unsigned a) {
+	union header *p, *q;
+
+	assert(a < NELEMS(arena));
+	for (p = arena[a]; p; p = q) {
+		q = (void *)p->b.next;
+		free(p);
+	}
+	arena[a] = NULL;
+}
+
+void *newarray(unsigned long m, unsigned long n, unsigned a) {
+	return allocate(m*n, a);
+}
+#else
+static struct block
+	 first[] = {  { NULL },  { NULL },  { NULL } },
+	*arena[] = { &first[0], &first[1], &first[2] };
+static struct block *freeblocks;
+
+void *allocate(unsigned long n, unsigned a) {
+	struct block *ap;
+
+	assert(a < NELEMS(arena));
+	assert(n > 0);
+	ap = arena[a];
+	n = roundup(n, sizeof (union align));
+	while (n > ap->limit - ap->avail) {
+		if ((ap->next = freeblocks) != NULL) {
+			freeblocks = freeblocks->next;
+			ap = ap->next;
+		} else
+			{
+				unsigned m = sizeof (union header) + n + roundup(10*1024, sizeof (union align));
+				ap->next = malloc(m);
+				ap = ap->next;
+				if (ap == NULL) {
+					error("insufficient memory\n");
+					exit(1);
+				}
+				ap->limit = (char *)ap + m;
+			}
+		ap->avail = (char *)((union header *)ap + 1);
+		ap->next = NULL;
+		arena[a] = ap;
+
+	}
+	ap->avail += n;
+	return ap->avail - n;
+}
+
+void *newarray(unsigned long m, unsigned long n, unsigned a) {
+	return allocate(m*n, a);
+}
+void deallocate(unsigned a) {
+	assert(a < NELEMS(arena));
+	arena[a]->next = freeblocks;
+	freeblocks = first[a].next;
+	first[a].next = NULL;
+	arena[a] = &first[a];
+}
+#endif