1 /**************************************************************************/
2 /*                                                                        */
3 /*                                 OCaml                                  */
4 /*                                                                        */
5 /*              Damien Doligez, projet Para, INRIA Rocquencourt           */
6 /*                                                                        */
7 /*   Copyright 1996 Institut National de Recherche en Informatique et     */
8 /*     en Automatique.                                                    */
9 /*                                                                        */
10 /*   All rights reserved.  This file is distributed under the terms of    */
11 /*   the GNU Lesser General Public License version 2.1, with the          */
12 /*   special exception on linking described in the file LICENSE.          */
13 /*                                                                        */
14 /**************************************************************************/
15 
16 /* Classification of addresses for GC and runtime purposes. */
17 
18 #ifndef CAML_ADDRESS_CLASS_H
19 #define CAML_ADDRESS_CLASS_H
20 
21 #include "config.h"
22 #include "misc.h"
23 #include "mlvalues.h"
24 
25 /* Use the following macros to test an address for the different classes
26    it might belong to. */
27 
28 #define Is_young(val) \
29   (Assert (Is_block (val)), \
30    (addr)(val) < (addr)caml_young_end && (addr)(val) > (addr)caml_young_start)
31 
32 #define Is_in_heap(a) (Classify_addr(a) & In_heap)
33 
34 #define Is_in_heap_or_young(a) (Classify_addr(a) & (In_heap | In_young))
35 
36 #define Is_in_value_area(a)                                     \
37   (Classify_addr(a) & (In_heap | In_young | In_static_data))
38 
39 #define Is_in_code_area(pc) \
40  (    ((char *)(pc) >= caml_code_area_start && \
41        (char *)(pc) <= caml_code_area_end)     \
42    || (Classify_addr(pc) & In_code_area) )
43 
44 #define Is_in_static_data(a) (Classify_addr(a) & In_static_data)
45 
46 /***********************************************************************/
47 /* The rest of this file is private and may change without notice. */
48 
49 extern value *caml_young_start, *caml_young_end;
50 extern char * caml_code_area_start, * caml_code_area_end;
51 
52 #define Not_in_heap 0
53 #define In_heap 1
54 #define In_young 2
55 #define In_static_data 4
56 #define In_code_area 8
57 
58 #ifdef ARCH_SIXTYFOUR
59 
60 /* 64 bits: Represent page table as a sparse hash table */
61 int caml_page_table_lookup(void * addr);
62 #define Classify_addr(a) (caml_page_table_lookup((void *)(a)))
63 
64 #else
65 
66 /* 32 bits: Represent page table as a 2-level array */
67 #define Pagetable2_log 11
68 #define Pagetable2_size (1 << Pagetable2_log)
69 #define Pagetable1_log (Page_log + Pagetable2_log)
70 #define Pagetable1_size (1 << (32 - Pagetable1_log))
71 CAMLextern unsigned char * caml_page_table[Pagetable1_size];
72 
73 #define Pagetable_index1(a) (((uintnat)(a)) >> Pagetable1_log)
74 #define Pagetable_index2(a) \
75   ((((uintnat)(a)) >> Page_log) & (Pagetable2_size - 1))
76 #define Classify_addr(a) \
77   caml_page_table[Pagetable_index1(a)][Pagetable_index2(a)]
78 
79 #endif
80 
81 int caml_page_table_add(int kind, void * start, void * end);
82 int caml_page_table_remove(int kind, void * start, void * end);
83 int caml_page_table_initialize(mlsize_t bytesize);
84 
85 #endif /* CAML_ADDRESS_CLASS_H */
86