2 * Generational Conservative Garbage Collector for SBCL x86
6 * This software is part of the SBCL system. See the README file for
9 * This software is derived from the CMU CL system, which was
10 * written at Carnegie Mellon University and released into the
11 * public domain. The software is in the public domain and is
12 * provided with absolutely no warranty. See the COPYING and CREDITS
13 * files for more information.
19 #include "genesis/code.h"
21 void gc_free_heap(void);
22 inline int find_page_index(void *);
23 inline void *page_address(int);
24 int gencgc_handle_wp_violation(void *);
25 lispobj *search_dynamic_space(lispobj *);
30 /* This is set when the page is write-protected. This should
31 * always reflect the actual write_protect status of a page.
32 * (If the page is written into, we catch the exception, make
33 * the page writable, and clear this flag.) */
35 /* This flag is set when the above write_protected flag is
36 * cleared by the SIGBUS handler (or SIGSEGV handler, for some
37 * OSes). This is useful for re-scavenging pages that are
38 * written during a GC. */
39 write_protected_cleared :1,
40 /* the region the page is allocated to: 0 for a free page; 1
41 * for boxed objects; 2 for unboxed objects. If the page is
42 * free the following slots are invalid (well the bytes_used
45 /* If this page should not be moved during a GC then this flag
46 * is set. It's only valid during a GC for allocated pages. */
48 /* If the page is part of a large object then this flag is
49 * set. No other objects should be allocated to these pages.
50 * This is only valid when the page is allocated. */
53 /* the generation that this page belongs to. This should be valid
54 * for all pages that may have objects allocated, even current
55 * allocation region pages - this allows the space of an object to
56 * be easily determined. */
59 /* the number of bytes of this page that are used. This may be less
60 * than the actual bytes used for pages within the current
61 * allocation regions. It should be 0 for all unallocated pages (not
62 * hard to achieve). */
65 /* It is important to know the offset to the first object in the
66 * page. Currently it's only important to know if an object starts
67 * at the beginning of the page in which case the offset would be 0. */
68 int first_object_offset;
71 /* values for the page.allocated field */
74 #define UNBOXED_PAGE 2
76 /* values for the *_alloc_* parameters */
78 #define ALLOC_UNBOXED 1
82 /* the number of pages needed for the dynamic space - rounding up */
83 #define NUM_PAGES ((DYNAMIC_SPACE_SIZE+4095)/4096)
84 extern struct page page_table[NUM_PAGES];
87 void gencgc_pickup_dynamic(void);
89 void sniff_code_object(struct code *code, unsigned displacement);
91 int update_x86_dynamic_space_free_pointer(void);
92 void gc_alloc_update_page_tables(int unboxed,
93 struct alloc_region *alloc_region);
94 void gc_alloc_update_all_page_tables(void);
95 void gc_set_region_empty(struct alloc_region *region);
96 #endif /* _GENCGC_H_ */