2 * Generational Conservative Garbage Collector for SBCL x86
4 * inline functions that gc-common.c needs sight of
9 * This software is part of the SBCL system. See the README file for
12 * This software is derived from the CMU CL system, which was
13 * written at Carnegie Mellon University and released into the
14 * public domain. The software is in the public domain and is
15 * provided with absolutely no warranty. See the COPYING and CREDITS
16 * files for more information.
19 #ifndef _GENCGC_INTERNAL_H_
20 #define _GENCGC_INTERNAL_H_
24 #include "gencgc-alloc-region.h"
25 #include "genesis/code.h"
27 void gc_free_heap(void);
28 inline page_index_t find_page_index(void *);
29 inline void *page_address(page_index_t);
30 int gencgc_handle_wp_violation(void *);
33 /* The name of this field is not well-chosen for its actual use.
34 * This is the offset from the start of the page to the start
35 * of the alloc_region which contains/contained it. It's negative or 0
37 long first_object_offset;
39 /* the number of bytes of this page that are used. This may be less
40 * than the actual bytes used for pages within the current
41 * allocation regions. It should be 0 for all unallocated pages (not
44 * Currently declared as an unsigned short to make the struct size
45 * smaller. This means that GENCGC-PAGE-SIZE is constrained to fit
48 unsigned short bytes_used;
50 #if USHRT_MAX < PAGE_BYTES
51 #error "PAGE_BYTES too large"
55 /* This is set when the page is write-protected. This should
56 * always reflect the actual write_protect status of a page.
57 * (If the page is written into, we catch the exception, make
58 * the page writable, and clear this flag.) */
60 /* This flag is set when the above write_protected flag is
61 * cleared by the SIGBUS handler (or SIGSEGV handler, for some
62 * OSes). This is useful for re-scavenging pages that are
63 * written during a GC. */
64 write_protected_cleared :1,
65 /* the region the page is allocated to: 0 for a free page; 1
66 * for boxed objects; 2 for unboxed objects. If the page is
67 * free the following slots are invalid (well the bytes_used
70 /* If this page should not be moved during a GC then this flag
71 * is set. It's only valid during a GC for allocated pages. */
73 /* If the page is part of a large object then this flag is
74 * set. No other objects should be allocated to these pages.
75 * This is only valid when the page is allocated. */
77 /* True if the page is known to contain only zeroes. */
80 /* the generation that this page belongs to. This should be valid
81 * for all pages that may have objects allocated, even current
82 * allocation region pages - this allows the space of an object to
83 * be easily determined. */
84 generation_index_t gen;
88 /* values for the page.allocated field */
91 extern unsigned page_table_pages;
92 extern struct page *page_table;
95 /* forward declarations */
97 void sniff_code_object(struct code *code, unsigned long displacement);
98 void gencgc_apply_code_fixups(struct code *old_code, struct code *new_code);
100 long update_dynamic_space_free_pointer(void);
101 void gc_alloc_update_page_tables(int unboxed,
102 struct alloc_region *alloc_region);
103 void gc_alloc_update_all_page_tables(void);
104 void gc_set_region_empty(struct alloc_region *region);
109 static inline boolean
110 space_matches_p(lispobj obj, generation_index_t space)
112 page_index_t page_index=(void*)obj - (void *)DYNAMIC_SPACE_START;
113 return ((page_index >= 0)
115 ((unsigned long)page_index)/PAGE_BYTES) < page_table_pages)
116 && (page_table[page_index].gen == space));
119 static inline boolean
120 from_space_p(lispobj obj)
122 return space_matches_p(obj,from_space);
125 static inline boolean
126 new_space_p(lispobj obj)
128 return space_matches_p(obj,new_space);
131 extern page_index_t last_free_page;
132 extern boolean gencgc_partial_pickup;