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.
23 void gc_free_heap(void);
24 inline int find_page_index(void *);
25 inline void *page_address(int);
26 int gencgc_handle_wp_violation(void *);
27 lispobj *search_dynamic_space(lispobj *);
32 /* This is set when the page is write-protected. This should
33 * always reflect the actual write_protect status of a page.
34 * (If the page is written into, we catch the exception, make
35 * the page writable, and clear this flag.) */
37 /* This flag is set when the above write_protected flag is
38 * cleared by the sigbus handler. This is useful for
39 * re-scavenging pages that are written during a GC. */
40 write_protected_cleared :1,
41 /* The region the page is allocated to: 0 for a free page; 1
42 * for boxed objects; 2 for unboxed objects. If the page is
43 * free the following slots are invalid (well the bytes_used
46 /* If this page should not be moved during a GC then this flag
47 * is set. It's only valid during a GC for allocated pages. */
49 /* If the page is part of a large object then this flag is
50 * set. No other objects should be allocated to these pages.
51 * This is only valid when the page is allocated. */
54 /* the generation that this page belongs to. This should be valid
55 * for all pages that may have objects allocated, even current
56 * allocation region pages - this allows the space of an object to
57 * be easily determined. */
60 /* the number of bytes of this page that are used. This may be less
61 * than the actual bytes used for pages within the current
62 * allocation regions. It should be 0 for all unallocated pages (not
63 * hard to achieve). */
66 /* It is important to know the offset to the first object in the
67 * page. Currently it's only important to know if an object starts
68 * at the beginning of the page in which case the offset would be 0. */
69 int first_object_offset;
74 #define UNBOXED_PAGE 2
76 /* the number of pages needed for the dynamic space - rounding up */
77 #define NUM_PAGES ((DYNAMIC_SPACE_SIZE+4095)/4096)
78 extern struct page page_table[NUM_PAGES];
80 /* Abstract out the data for an allocation region allowing a single
81 * routine to be used for allocation and closing. */
84 /* These two are needed for quick allocation. */
86 void *end_addr; /* pointer to the byte after the last usable byte */
88 /* needed when closing the region */
94 extern struct alloc_region boxed_region;
95 extern struct alloc_region unboxed_region;
97 void gencgc_pickup_dynamic(void);
99 void sniff_code_object(struct code *code, unsigned displacement);
101 int update_x86_dynamic_space_free_pointer(void);
102 void gc_alloc_update_page_tables(int unboxed,
103 struct alloc_region *alloc_region);