#include "genesis/code.h"
void gc_free_heap(void);
-inline page_index_t find_page_index(void *);
-inline void *page_address(page_index_t);
+extern page_index_t find_page_index(void *);
+extern void *page_address(page_index_t);
int gencgc_handle_wp_violation(void *);
\f
+
+#if GENCGC_CARD_BYTES > USHRT_MAX
+# if GENCGC_CARD_BYTES > UINT_MAX
+# error "GENCGC_CARD_BYTES unexpectedly large."
+# else
+# define PAGE_BYTES_FMT "u"
+ typedef unsigned int page_bytes_t;
+# endif
+#else
+# define PAGE_BYTES_FMT "hu"
+ typedef unsigned short page_bytes_t;
+#endif
+
+/* 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
+ /* This is the offset from the first byte of some object in memory
+ * prior to and no closer than the start of the page to the start
+ * of the page. Lower values here are better, 0 is ideal. This
+ * is useful for determining where to start when scanning forward
+ * through a heap page (either for conservative root validation or
+ * for scavenging).
*/
- long first_object_offset;
+ os_vm_size_t scan_start_offset;
/* 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).
- *
- * Currently declared as an unsigned short to make the struct size
- * smaller. This means that GENCGC-PAGE-SIZE is constrained to fit
- * inside a short.
*/
- unsigned short bytes_used;
+ page_bytes_t bytes_used;
-#if USHRT_MAX < PAGE_BYTES
-#error "PAGE_BYTES too large"
-#endif
-
- unsigned
+ unsigned char
/* 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
* OSes). This is useful for re-scavenging pages that are
* written during a GC. */
write_protected_cleared :1,
- /* the region the page is allocated to: 0 for a free page; 1
- * for boxed objects; 2 for unboxed objects. If the page is
- * free the following slots are invalid (well the bytes_used
- * must be 0). */
+ /* 000 free
+ * ?01 boxed data
+ * ?10 unboxed data
+ * ?11 code
+ * 1?? open region
+ *
+ * Constants for this field are defined in gc-internal.h, the
+ * xxx_PAGE_FLAG definitions.
+ *
+ * If the page is free the following slots are invalid, except
+ * for the bytes_used which must be zero. */
allocated :3,
/* If this page should not be moved during a GC then this flag
* is set. It's only valid during a GC for allocated pages. */
* set. No other objects should be allocated to these pages.
* This is only valid when the page is allocated. */
large_object :1,
- /* True if the page is known to contain only zeroes. */
+ /* Cleared if the page is known to contain only zeroes. */
need_to_zero :1;
/* the generation that this page belongs to. This should be valid
/* values for the page.allocated field */
\f
-extern unsigned page_table_pages;
+extern page_index_t page_table_pages;
extern struct page *page_table;
\f
/* forward declarations */
-
-void sniff_code_object(struct code *code, unsigned long displacement);
+#ifdef LISP_FEATURE_X86
+void sniff_code_object(struct code *code, os_vm_size_t displacement);
void gencgc_apply_code_fixups(struct code *old_code, struct code *new_code);
+#endif
-long update_dynamic_space_free_pointer(void);
-void gc_alloc_update_page_tables(int unboxed,
- struct alloc_region *alloc_region);
+sword_t update_dynamic_space_free_pointer(void);
+void gc_alloc_update_page_tables(int page_type_flag, struct alloc_region *alloc_region);
void gc_alloc_update_all_page_tables(void);
void gc_set_region_empty(struct alloc_region *region);
/*
* predicates
*/
+
static inline boolean
space_matches_p(lispobj obj, generation_index_t space)
{
- page_index_t page_index=(void*)obj - (void *)DYNAMIC_SPACE_START;
- return ((page_index >= 0)
- && ((page_index =
- ((unsigned long)page_index)/PAGE_BYTES) < page_table_pages)
- && (page_table[page_index].gen == space));
+ if (obj >= DYNAMIC_SPACE_START) {
+ page_index_t page_index=((pointer_sized_uint_t)obj
+ - DYNAMIC_SPACE_START) / GENCGC_CARD_BYTES;
+ return ((page_index < page_table_pages) &&
+ (page_table[page_index].gen == space));
+ } else {
+ return 0;
+ }
}
static inline boolean