1 files changed, 90 insertions, 0 deletions
diff --git a/boehm_gc/obj_map.c b/boehm_gc/obj_map.c
new file mode 100644
index 0000000..c295c40
--- /dev/null
+++ b/boehm_gc/obj_map.c
@@ -0,0 +1,90 @@
+/* 
+ * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
+ * Copyright (c) 1991, 1992 by Xerox Corporation.  All rights reserved.
+ * Copyright (c) 1999-2001 by Hewlett-Packard Company. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose,  provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+  
+/* Routines for maintaining maps describing heap block
+ * layouts for various object sizes.  Allows fast pointer validity checks
+ * and fast location of object start locations on machines (such as SPARC)
+ * with slow division.
+ */
+ 
+# include "private/gc_priv.h"
+
+/* Consider pointers that are offset bytes displaced from the beginning */
+/* of an object to be valid.                                            */
+
+void GC_register_displacement(size_t offset)
+{
+    DCL_LOCK_STATE;
+    
+    LOCK();
+    GC_register_displacement_inner(offset);
+    UNLOCK();
+}
+
+void GC_register_displacement_inner(size_t offset) 
+{
+    if (offset >= VALID_OFFSET_SZ) {
+        ABORT("Bad argument to GC_register_displacement");
+    }
+    if (!GC_valid_offsets[offset]) {
+      GC_valid_offsets[offset] = TRUE;
+      GC_modws_valid_offsets[offset % sizeof(word)] = TRUE;
+    }
+}
+
+#ifdef MARK_BIT_PER_GRANULE
+/* Add a heap block map for objects of size granules to obj_map.	*/
+/* Return FALSE on failure.						*/
+/* A size of 0 granules is used for large objects.			*/
+GC_bool GC_add_map_entry(size_t granules)
+{
+    unsigned displ;
+    short * new_map;
+    
+    if (granules > BYTES_TO_GRANULES(MAXOBJBYTES)) granules = 0;
+    if (GC_obj_map[granules] != 0) {
+        return(TRUE);
+    }
+    new_map = (short *)GC_scratch_alloc(MAP_LEN * sizeof(short));
+    if (new_map == 0) return(FALSE);
+    if (GC_print_stats)
+        GC_printf("Adding block map for size of %u granules (%u bytes)\n",
+		  (unsigned)granules, (unsigned)(GRANULES_TO_BYTES(granules)));
+    if (granules == 0) {
+      for (displ = 0; displ < BYTES_TO_GRANULES(HBLKSIZE); displ++) {
+        new_map[displ] = 1;  /* Nonzero to get us out of marker fast path. */
+      }
+    } else {
+      for (displ = 0; displ < BYTES_TO_GRANULES(HBLKSIZE); displ++) {
+	new_map[displ] = (short)(displ % granules);
+      }
+    }
+    GC_obj_map[granules] = new_map;
+    return(TRUE);
+}
+#endif
+
+static GC_bool offsets_initialized = FALSE;
+
+void GC_initialize_offsets(void)
+{
+    if (!offsets_initialized) {
+      int i;
+      if (GC_all_interior_pointers) {
+	for (i = 0; i < VALID_OFFSET_SZ; ++i) GC_valid_offsets[i] = TRUE;
+      }
+      offsets_initialized = TRUE;
+    }
+}