#ifndef _GENCGC_INTERNAL_H_
#define _GENCGC_INTERNAL_H_
+#include <limits.h>
#include "gc.h"
#include "gencgc-alloc-region.h"
#include "genesis/code.h"
-/* Size of a page, in bytes. FIXME: needs to be conditionalized per
- * architecture, preferably by someone with a clue as to what page
- * sizes are on archs other than x86 and PPC - Patrik */
-#define PAGE_BYTES 4096
-
void gc_free_heap(void);
inline page_index_t find_page_index(void *);
inline void *page_address(page_index_t);
int gencgc_handle_wp_violation(void *);
\f
+
+/* Note that this structure is also used from Lisp-side in
+ * src/code/room.lisp, and the Lisp-side structure layout is currently
+ * not groveled from C code but hardcoded. Any changes to the
+ * structure layout need to be also made there.
+ *
+ * FIXME: We should probably just define this structure in Lisp, and
+ * output the C version in genesis. -- JES, 2006-12-30.
+ */
struct page {
+ /* The name of this field is not well-chosen for its actual use.
+ * This is the offset from the start of the page to the start
+ * of the alloc_region which contains/contained it. It's negative or 0
+ */
+ long first_object_offset;
- unsigned int
+ /* the number of bytes of this page that are used. This may be less
+ * than the actual bytes used for pages within the current
+ * allocation regions. It should be 0 for all unallocated pages (not
+ * hard to achieve).
+ */
+#if PAGE_BYTES > USHRT_MAX
+ unsigned int bytes_used;
+#else
+ unsigned short bytes_used;
+#endif
+
+ unsigned
/* This is set when the page is write-protected. This should
* always reflect the actual write_protect status of a page.
* (If the page is written into, we catch the exception, make
/* If the page is part of a large object then this flag is
* set. No other objects should be allocated to these pages.
* This is only valid when the page is allocated. */
- large_object :1;
+ large_object :1,
+ /* True if the page is known to contain only zeroes. */
+ need_to_zero :1;
/* the generation that this page belongs to. This should be valid
* for all pages that may have objects allocated, even current
* allocation region pages - this allows the space of an object to
* be easily determined. */
generation_index_t gen;
-
- /* the number of bytes of this page that are used. This may be less
- * than the actual bytes used for pages within the current
- * allocation regions. It should be 0 for all unallocated pages (not
- * hard to achieve). */
- int bytes_used;
-
- /* The name of this field is not well-chosen for its actual use.
- * This is the offset from the start of the page to the start
- * of the alloc_region which contains/contained it. It's negative or 0
- */
- long first_object_offset;
};
+
/* values for the page.allocated field */
\f
-/* the number of pages needed for the dynamic space - rounding up */
-#define NUM_PAGES ((page_index_t) ((DYNAMIC_SPACE_SIZE+PAGE_BYTES-1)/PAGE_BYTES))
-
-extern struct page page_table[NUM_PAGES];
+extern page_index_t page_table_pages;
+extern struct page *page_table;
\f
/* forward declarations */
page_index_t page_index=(void*)obj - (void *)DYNAMIC_SPACE_START;
return ((page_index >= 0)
&& ((page_index =
- ((unsigned long)page_index)/PAGE_BYTES) < NUM_PAGES)
+ ((unsigned long)page_index)/PAGE_BYTES) < page_table_pages)
&& (page_table[page_index].gen == space));
}