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-rw-r--r--ptr_chck.c82
1 files changed, 42 insertions, 40 deletions
diff --git a/ptr_chck.c b/ptr_chck.c
index f3451ee..af49d5f 100644
--- a/ptr_chck.c
+++ b/ptr_chck.c
@@ -10,10 +10,13 @@
* 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"
+/*
+ * These are checking routines calls to which could be inserted by a
+ * preprocessor to validate C pointer arithmetic.
+ */
+
+#include "private/gc_pmark.h"
#ifdef __STDC__
void GC_default_same_obj_print_proc(GC_PTR p, GC_PTR q)
@@ -69,7 +72,7 @@ void (*GC_same_obj_print_proc) GC_PROTO((GC_PTR, GC_PTR))
h = FORWARDED_ADDR(h, hhdr);
hhdr = HDR(h);
}
- limit = (ptr_t)((word *)h + HDR_WORDS + hhdr -> hb_sz);
+ limit = (ptr_t)((word *)h + hhdr -> hb_sz);
if ((ptr_t)p >= limit || (ptr_t)q >= limit || (ptr_t)q < (ptr_t)h ) {
goto fail;
}
@@ -83,28 +86,19 @@ void (*GC_same_obj_print_proc) GC_PROTO((GC_PTR, GC_PTR))
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
+ register int map_entry;
+ register int pdispl = HBLKDISPL(p);
+
+ map_entry = MAP_ENTRY((hhdr -> hb_map), pdispl);
+ if (map_entry > CPP_MAX_OFFSET) {
+ map_entry = BYTES_TO_WORDS(pdispl) % BYTES_TO_WORDS(sz);
+ if (HBLKPTR(p) != HBLKPTR(q)) goto fail;
+ /* W/o this check, we might miss an error if */
+ /* q points to the first object on a page, and */
+ /* points just before the page. */
+ }
+ base = (char *)((word)p & ~(WORDS_TO_BYTES(1) - 1));
+ base -= WORDS_TO_BYTES(map_entry);
limit = base + sz;
}
/* [base, limit) delimits the object containing p, if any. */
@@ -137,7 +131,7 @@ void (*GC_is_valid_displacement_print_proc) GC_PROTO((GC_PTR)) =
/* 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. */
+/* Uninteresting with GC_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. */
@@ -158,12 +152,12 @@ void (*GC_is_valid_displacement_print_proc) GC_PROTO((GC_PTR)) =
hhdr = HDR((word)p);
if (hhdr == 0) return(p);
h = HBLKPTR(p);
-# ifdef ALL_INTERIOR_POINTERS
+ if (GC_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;
}
@@ -252,7 +246,8 @@ ptr_t p;
if (GC_is_static_root(p)) return(p);
/* Else do it again correctly: */
-# if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || defined(PCR)) \
+# if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || \
+ defined(MSWINCE) || defined(PCR)) \
&& !defined(SRC_M3)
DISABLE_SIGNALS();
GC_register_dynamic_libraries();
@@ -270,23 +265,30 @@ ptr_t p;
if (HBLKPTR(base) != HBLKPTR(p)) hhdr = HDR((word)p);
descr = hhdr -> hb_descr;
retry:
- switch(descr & DS_TAGS) {
- case DS_LENGTH:
+ switch(descr & GC_DS_TAGS) {
+ case GC_DS_LENGTH:
if ((word)((ptr_t)p - (ptr_t)base) > (word)descr) goto fail;
break;
- case DS_BITMAP:
+ case GC_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:
+ case GC_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));
+ case GC_DS_PER_OBJECT:
+ if ((signed_word)descr >= 0) {
+ descr = *(word *)((ptr_t)base + (descr & ~GC_DS_TAGS));
+ } else {
+ ptr_t type_descr = *(ptr_t *)base;
+ descr = *(word *)(type_descr
+ - (descr - (GC_DS_PER_OBJECT
+ - GC_INDIR_PER_OBJ_BIAS)));
+ }
goto retry;
}
return(p);
@@ -305,9 +307,9 @@ 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
+ if (!GC_all_interior_pointers) {
(void) GC_is_valid_displacement(result);
-# endif
+ }
return (*p = result);
}
@@ -318,9 +320,9 @@ 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
+ if (!GC_all_interior_pointers) {
(void) GC_is_valid_displacement(result);
-# endif
+ }
*p = result;
return(initial);
}