mirror of
https://github.com/rn10950/RetroZilla.git
synced 2024-08-29 17:10:46 +02:00
327 lines
9.2 KiB
C
327 lines
9.2 KiB
C
|
/*
|
||
|
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
|
||
|
*
|
||
|
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
|
||
|
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
|
||
|
*
|
||
|
* Permission is hereby granted to use or copy this program
|
||
|
* for any purpose, provided the above notices are retained on all copies.
|
||
|
* Permission to modify the code and to distribute modified code is granted,
|
||
|
* provided the above notices are retained, and a notice that the code was
|
||
|
* modified is included with the above copyright notice.
|
||
|
*/
|
||
|
/* Boehm, September 19, 1995 1:26 pm PDT */
|
||
|
|
||
|
#include "gc_priv.h"
|
||
|
#include "gc_mark.h"
|
||
|
|
||
|
#ifdef __STDC__
|
||
|
void GC_default_same_obj_print_proc(GC_PTR p, GC_PTR q)
|
||
|
#else
|
||
|
void GC_default_same_obj_print_proc (p, q)
|
||
|
GC_PTR p, q;
|
||
|
#endif
|
||
|
{
|
||
|
GC_err_printf2("0x%lx and 0x%lx are not in the same object\n",
|
||
|
(unsigned long)p, (unsigned long)q);
|
||
|
ABORT("GC_same_obj test failed");
|
||
|
}
|
||
|
|
||
|
void (*GC_same_obj_print_proc) GC_PROTO((GC_PTR, GC_PTR))
|
||
|
= GC_default_same_obj_print_proc;
|
||
|
|
||
|
/* Check that p and q point to the same object. Call */
|
||
|
/* *GC_same_obj_print_proc if they don't. */
|
||
|
/* Returns the first argument. (Return value may be hard */
|
||
|
/* to use,due to typing issues. But if we had a suitable */
|
||
|
/* preprocessor ...) */
|
||
|
/* Succeeds if neither p nor q points to the heap. */
|
||
|
/* We assume this is performance critical. (It shouldn't */
|
||
|
/* be called by production code, but this can easily make */
|
||
|
/* debugging intolerably slow.) */
|
||
|
#ifdef __STDC__
|
||
|
GC_PTR GC_same_obj(register void *p, register void *q)
|
||
|
#else
|
||
|
GC_PTR GC_same_obj(p, q)
|
||
|
register char *p, *q;
|
||
|
#endif
|
||
|
{
|
||
|
register struct hblk *h;
|
||
|
register hdr *hhdr;
|
||
|
register ptr_t base, limit;
|
||
|
register word sz;
|
||
|
|
||
|
if (!GC_is_initialized) GC_init();
|
||
|
hhdr = HDR((word)p);
|
||
|
if (hhdr == 0) {
|
||
|
if (divHBLKSZ((word)p) != divHBLKSZ((word)q)
|
||
|
&& HDR((word)q) != 0) {
|
||
|
goto fail;
|
||
|
}
|
||
|
return(p);
|
||
|
}
|
||
|
/* If it's a pointer to the middle of a large object, move it */
|
||
|
/* to the beginning. */
|
||
|
if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
|
||
|
h = HBLKPTR(p) - (word)hhdr;
|
||
|
hhdr = HDR(h);
|
||
|
while (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
|
||
|
h = FORWARDED_ADDR(h, hhdr);
|
||
|
hhdr = HDR(h);
|
||
|
}
|
||
|
limit = (ptr_t)((word *)h + HDR_WORDS + hhdr -> hb_sz);
|
||
|
if ((ptr_t)p >= limit || (ptr_t)q >= limit || (ptr_t)q < (ptr_t)h ) {
|
||
|
goto fail;
|
||
|
}
|
||
|
return(p);
|
||
|
}
|
||
|
sz = WORDS_TO_BYTES(hhdr -> hb_sz);
|
||
|
if (sz > WORDS_TO_BYTES(MAXOBJSZ)) {
|
||
|
base = (ptr_t)HBLKPTR(p);
|
||
|
limit = base + sz;
|
||
|
if ((ptr_t)p >= limit) {
|
||
|
goto fail;
|
||
|
}
|
||
|
} else {
|
||
|
# ifdef ALL_INTERIOR_POINTERS
|
||
|
register map_entry_type map_entry;
|
||
|
register int pdispl;
|
||
|
|
||
|
pdispl = HBLKDISPL(p);
|
||
|
map_entry = MAP_ENTRY((hhdr -> hb_map), pdispl);
|
||
|
if (map_entry == OBJ_INVALID) {
|
||
|
goto fail;
|
||
|
} else {
|
||
|
base = (char *)((word)p & ~(WORDS_TO_BYTES(1) - 1));
|
||
|
base -= WORDS_TO_BYTES(map_entry);
|
||
|
}
|
||
|
# else
|
||
|
register int offset = HBLKDISPL(p) - HDR_BYTES;
|
||
|
register word correction = offset % sz;
|
||
|
|
||
|
if (HBLKPTR(p) != HBLKPTR(q)) {
|
||
|
/* The following computation otherwise fails in this case */
|
||
|
goto fail;
|
||
|
}
|
||
|
base = (ptr_t)p - correction;
|
||
|
# endif
|
||
|
limit = base + sz;
|
||
|
}
|
||
|
/* [base, limit) delimits the object containing p, if any. */
|
||
|
/* If p is not inside a valid object, then either q is */
|
||
|
/* also outside any valid object, or it is outside */
|
||
|
/* [base, limit). */
|
||
|
if ((ptr_t)q >= limit || (ptr_t)q < base) {
|
||
|
goto fail;
|
||
|
}
|
||
|
return(p);
|
||
|
fail:
|
||
|
(*GC_same_obj_print_proc)((ptr_t)p, (ptr_t)q);
|
||
|
return(p);
|
||
|
}
|
||
|
|
||
|
#ifdef __STDC__
|
||
|
void GC_default_is_valid_displacement_print_proc (GC_PTR p)
|
||
|
#else
|
||
|
void GC_default_is_valid_displacement_print_proc (p)
|
||
|
GC_PTR p;
|
||
|
#endif
|
||
|
{
|
||
|
GC_err_printf1("0x%lx does not point to valid object displacement\n",
|
||
|
(unsigned long)p);
|
||
|
ABORT("GC_is_valid_displacement test failed");
|
||
|
}
|
||
|
|
||
|
void (*GC_is_valid_displacement_print_proc) GC_PROTO((GC_PTR)) =
|
||
|
GC_default_is_valid_displacement_print_proc;
|
||
|
|
||
|
/* Check that if p is a pointer to a heap page, then it points to */
|
||
|
/* a valid displacement within a heap object. */
|
||
|
/* Uninteresting with ALL_INTERIOR_POINTERS. */
|
||
|
/* Always returns its argument. */
|
||
|
/* Note that we don't lock, since nothing relevant about the header */
|
||
|
/* should change while we have a valid object pointer to the block. */
|
||
|
#ifdef __STDC__
|
||
|
void * GC_is_valid_displacement(void *p)
|
||
|
#else
|
||
|
char *GC_is_valid_displacement(p)
|
||
|
char *p;
|
||
|
#endif
|
||
|
{
|
||
|
register hdr *hhdr;
|
||
|
register word pdispl;
|
||
|
register struct hblk *h;
|
||
|
register map_entry_type map_entry;
|
||
|
register word sz;
|
||
|
|
||
|
if (!GC_is_initialized) GC_init();
|
||
|
hhdr = HDR((word)p);
|
||
|
if (hhdr == 0) return(p);
|
||
|
h = HBLKPTR(p);
|
||
|
# ifdef ALL_INTERIOR_POINTERS
|
||
|
while (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
|
||
|
h = FORWARDED_ADDR(h, hhdr);
|
||
|
hhdr = HDR(h);
|
||
|
}
|
||
|
# endif
|
||
|
if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
|
||
|
goto fail;
|
||
|
}
|
||
|
sz = WORDS_TO_BYTES(hhdr -> hb_sz);
|
||
|
pdispl = HBLKDISPL(p);
|
||
|
map_entry = MAP_ENTRY((hhdr -> hb_map), pdispl);
|
||
|
if (map_entry == OBJ_INVALID
|
||
|
|| sz > MAXOBJSZ && (ptr_t)p >= (ptr_t)h + sz) {
|
||
|
goto fail;
|
||
|
}
|
||
|
return(p);
|
||
|
fail:
|
||
|
(*GC_is_valid_displacement_print_proc)((ptr_t)p);
|
||
|
return(p);
|
||
|
}
|
||
|
|
||
|
#ifdef __STDC__
|
||
|
void GC_default_is_visible_print_proc(GC_PTR p)
|
||
|
#else
|
||
|
void GC_default_is_visible_print_proc(p)
|
||
|
GC_PTR p;
|
||
|
#endif
|
||
|
{
|
||
|
GC_err_printf1("0x%lx is not a GC visible pointer location\n",
|
||
|
(unsigned long)p);
|
||
|
ABORT("GC_is_visible test failed");
|
||
|
}
|
||
|
|
||
|
void (*GC_is_visible_print_proc) GC_PROTO((GC_PTR p)) =
|
||
|
GC_default_is_visible_print_proc;
|
||
|
|
||
|
/* Could p be a stack address? */
|
||
|
GC_bool GC_on_stack(p)
|
||
|
ptr_t p;
|
||
|
{
|
||
|
# ifdef THREADS
|
||
|
return(TRUE);
|
||
|
# else
|
||
|
int dummy;
|
||
|
# ifdef STACK_GROWS_DOWN
|
||
|
if ((ptr_t)p >= (ptr_t)(&dummy) && (ptr_t)p < GC_stackbottom ) {
|
||
|
return(TRUE);
|
||
|
}
|
||
|
# else
|
||
|
if ((ptr_t)p <= (ptr_t)(&dummy) && (ptr_t)p > GC_stackbottom ) {
|
||
|
return(TRUE);
|
||
|
}
|
||
|
# endif
|
||
|
return(FALSE);
|
||
|
# endif
|
||
|
}
|
||
|
|
||
|
/* Check that p is visible */
|
||
|
/* to the collector as a possibly pointer containing location. */
|
||
|
/* If it isn't invoke *GC_is_visible_print_proc. */
|
||
|
/* Returns the argument in all cases. May erroneously succeed */
|
||
|
/* in hard cases. (This is intended for debugging use with */
|
||
|
/* untyped allocations. The idea is that it should be possible, though */
|
||
|
/* slow, to add such a call to all indirect pointer stores.) */
|
||
|
/* Currently useless for multithreaded worlds. */
|
||
|
#ifdef __STDC__
|
||
|
void * GC_is_visible(void *p)
|
||
|
#else
|
||
|
char *GC_is_visible(p)
|
||
|
char *p;
|
||
|
#endif
|
||
|
{
|
||
|
register hdr *hhdr;
|
||
|
|
||
|
if ((word)p & (ALIGNMENT - 1)) goto fail;
|
||
|
if (!GC_is_initialized) GC_init();
|
||
|
# ifdef THREADS
|
||
|
hhdr = HDR((word)p);
|
||
|
if (hhdr != 0 && GC_base(p) == 0) {
|
||
|
goto fail;
|
||
|
} else {
|
||
|
/* May be inside thread stack. We can't do much. */
|
||
|
return(p);
|
||
|
}
|
||
|
# else
|
||
|
/* Check stack first: */
|
||
|
if (GC_on_stack(p)) return(p);
|
||
|
hhdr = HDR((word)p);
|
||
|
if (hhdr == 0) {
|
||
|
GC_bool result;
|
||
|
|
||
|
if (GC_is_static_root(p)) return(p);
|
||
|
/* Else do it again correctly: */
|
||
|
# if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || defined(PCR)) \
|
||
|
&& !defined(SRC_M3)
|
||
|
DISABLE_SIGNALS();
|
||
|
GC_register_dynamic_libraries();
|
||
|
result = GC_is_static_root(p);
|
||
|
ENABLE_SIGNALS();
|
||
|
if (result) return(p);
|
||
|
# endif
|
||
|
goto fail;
|
||
|
} else {
|
||
|
/* p points to the heap. */
|
||
|
word descr;
|
||
|
ptr_t base = GC_base(p); /* Should be manually inlined? */
|
||
|
|
||
|
if (base == 0) goto fail;
|
||
|
if (HBLKPTR(base) != HBLKPTR(p)) hhdr = HDR((word)p);
|
||
|
descr = hhdr -> hb_descr;
|
||
|
retry:
|
||
|
switch(descr & DS_TAGS) {
|
||
|
case DS_LENGTH:
|
||
|
if ((word)((ptr_t)p - (ptr_t)base) > (word)descr) goto fail;
|
||
|
break;
|
||
|
case DS_BITMAP:
|
||
|
if ((ptr_t)p - (ptr_t)base
|
||
|
>= WORDS_TO_BYTES(BITMAP_BITS)
|
||
|
|| ((word)p & (sizeof(word) - 1))) goto fail;
|
||
|
if (!((1 << (WORDSZ - ((ptr_t)p - (ptr_t)base) - 1))
|
||
|
& descr)) goto fail;
|
||
|
break;
|
||
|
case DS_PROC:
|
||
|
/* We could try to decipher this partially. */
|
||
|
/* For now we just punt. */
|
||
|
break;
|
||
|
case DS_PER_OBJECT:
|
||
|
descr = *(word *)((ptr_t)base + (descr & ~DS_TAGS));
|
||
|
goto retry;
|
||
|
}
|
||
|
return(p);
|
||
|
}
|
||
|
# endif
|
||
|
fail:
|
||
|
(*GC_is_visible_print_proc)((ptr_t)p);
|
||
|
return(p);
|
||
|
}
|
||
|
|
||
|
|
||
|
GC_PTR GC_pre_incr (p, how_much)
|
||
|
GC_PTR *p;
|
||
|
size_t how_much;
|
||
|
{
|
||
|
GC_PTR initial = *p;
|
||
|
GC_PTR result = GC_same_obj((GC_PTR)((word)initial + how_much), initial);
|
||
|
|
||
|
# ifndef ALL_INTERIOR_POINTERS
|
||
|
(void) GC_is_valid_displacement(result);
|
||
|
# endif
|
||
|
return (*p = result);
|
||
|
}
|
||
|
|
||
|
GC_PTR GC_post_incr (p, how_much)
|
||
|
GC_PTR *p;
|
||
|
size_t how_much;
|
||
|
{
|
||
|
GC_PTR initial = *p;
|
||
|
GC_PTR result = GC_same_obj((GC_PTR)((word)initial + how_much), initial);
|
||
|
|
||
|
# ifndef ALL_INTERIOR_POINTERS
|
||
|
(void) GC_is_valid_displacement(result);
|
||
|
# endif
|
||
|
*p = result;
|
||
|
return(initial);
|
||
|
}
|