2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
4 * Copyright 1996-1999 by Silicon Graphics. All rights reserved.
5 * Copyright 1999 by Hewlett-Packard Company. All rights reserved.
7 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
8 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
10 * Permission is hereby granted to use or copy this program
11 * for any purpose, provided the above notices are retained on all copies.
12 * Permission to modify the code and to distribute modified code is granted,
13 * provided the above notices are retained, and a notice that the code was
14 * modified is included with the above copyright notice.
17 /* This file assumes the collector has been compiled with GC_GCJ_SUPPORT. */
20 * We allocate objects whose first word contains a pointer to a struct
21 * describing the object type. This struct contains a garbage collector mark
22 * descriptor at offset MARK_DESCR_OFFSET. Alternatively, the objects
23 * may be marked by the mark procedure passed to GC_init_gcj_malloc.
30 /* Gcj keeps GC descriptor as second word of vtable. This */
31 /* probably needs to be adjusted for other clients. */
32 /* We currently assume that this offset is such that: */
33 /* - all objects of this kind are large enough to have */
34 /* a value at that offset, and */
35 /* - it is not zero. */
36 /* These assumptions allow objects on the free list to be */
37 /* marked normally. */
47 /* The following allocators signal an out of memory condition with */
48 /* return GC_oom_fn(bytes); */
50 /* The following function must be called before the gcj allocators */
52 /* mp_index and mp are the index and mark_proc (see gc_mark.h) */
53 /* respectively for the allocated objects. Mark_proc will be */
54 /* used to build the descriptor for objects allocated through the */
55 /* debugging interface. The mark_proc will be invoked on all such */
56 /* objects with an "environment" value of 1. The client may choose */
57 /* to use the same mark_proc for some of its generated mark descriptors.*/
58 /* In that case, it should use a different "environment" value to */
59 /* detect the presence or absence of the debug header. */
60 /* Mp is really of type mark_proc, as defined in gc_mark.h. We don't */
61 /* want to include that here for namespace pollution reasons. */
62 /* Passing in mp_index here instead of having GC_init_gcj_malloc() */
63 /* internally call GC_new_proc() is quite ugly, but in typical usage */
64 /* scenarios a compiler also has to know about mp_index, so */
65 /* generating it dynamically is not acceptable. Mp_index will */
66 /* typically be an integer < RESERVED_MARK_PROCS, so that it doesn't */
67 /* collide with GC_new_proc allocated indices. If the application */
68 /* needs no other reserved indices, zero */
69 /* (GC_GCJ_RESERVED_MARK_PROC_INDEX in gc_mark.h) is an obvious choice. */
70 GC_API void GC_CALL GC_init_gcj_malloc(int mp_index,
71 void * /* really mark_proc */mp);
73 /* Allocate an object, clear it, and store the pointer to the */
74 /* type structure (vtable in gcj). */
75 /* This adds a byte at the end of the object if GC_malloc would.*/
76 GC_API void * GC_CALL GC_gcj_malloc(size_t lb,
77 void * ptr_to_struct_containing_descr);
78 /* The debug versions allocate such that the specified mark_proc */
79 /* is always invoked. */
80 GC_API void * GC_CALL GC_debug_gcj_malloc(size_t lb,
81 void * ptr_to_struct_containing_descr,
84 /* Similar to GC_gcj_malloc, but assumes that a pointer to near the */
85 /* beginning of the resulting object is always maintained. */
86 GC_API void * GC_CALL GC_gcj_malloc_ignore_off_page(size_t lb,
87 void * ptr_to_struct_containing_descr);
89 /* The kind numbers of normal and debug gcj objects. */
90 /* Useful only for debug support, we hope. */
91 GC_API int GC_gcj_kind;
93 GC_API int GC_gcj_debug_kind;
96 # define GC_GCJ_MALLOC(s,d) GC_debug_gcj_malloc(s,d,GC_EXTRAS)
97 # define GC_GCJ_MALLOC_IGNORE_OFF_PAGE(s,d) GC_debug_gcj_malloc(s,d,GC_EXTRAS)
99 # define GC_GCJ_MALLOC(s,d) GC_gcj_malloc(s,d)
100 # define GC_GCJ_MALLOC_IGNORE_OFF_PAGE(s,d) \
101 GC_gcj_malloc_ignore_off_page(s,d)
105 } /* end of extern "C" */
108 #endif /* GC_GCJ_H */