1 files changed, 60 insertions, 0 deletions
diff --git a/byterun/stacks.c b/byterun/stacks.c
new file mode 100644
index 0000000000..c831538590
--- /dev/null
+++ b/byterun/stacks.c
@@ -0,0 +1,60 @@
+/* To initialize and resize the stacks */
+
+#include <string.h>
+#include "config.h"
+#include "fail.h"
+#include "misc.h"
+#include "mlvalues.h"
+#include "stacks.h"
+
+value * stack_low;
+value * stack_high;
+value * stack_threshold;
+value * extern_sp;
+value * trapsp;
+value global_data;
+
+void init_stack()
+{
+  stack_low = (value *) stat_alloc(Stack_size);
+  stack_high = stack_low + Stack_size / sizeof (value);
+  stack_threshold = stack_low + Stack_threshold / sizeof (value);
+  extern_sp = stack_high;
+  trapsp = stack_high;
+}
+
+void realloc_stack()
+{        
+  asize_t size;
+  value * new_low, * new_high, * new_sp;
+  value * p;
+
+  Assert(extern_sp >= stack_low);
+  size = stack_high - stack_low;
+  if (size >= Max_stack_size)
+    raise_out_of_memory();
+  size *= 2;
+  gc_message ("Growing stack to %ld kB.\n",
+	      (long) size * sizeof(value) / 1024);
+  new_low = (value *) stat_alloc(size * sizeof(value));
+  new_high = new_low + size;
+
+#define shift(ptr) \
+    ((char *) new_high - ((char *) stack_high - (char *) (ptr)))
+
+  new_sp = (value *) shift(extern_sp);
+  bcopy((char *) extern_sp,
+        (char *) new_sp,
+        (stack_high - extern_sp) * sizeof(value));
+  stat_free((char *) stack_low);
+  trapsp = (value *) shift(trapsp);
+  for (p = trapsp; p < new_high; p = Trap_link(p))
+    Trap_link(p) = (value *) shift(Trap_link(p));
+  stack_low = new_low;
+  stack_high = new_high;
+  stack_threshold = stack_low + Stack_threshold / sizeof (value);
+  extern_sp = new_sp;
+
+#undef shift
+}
+