diff options
Diffstat (limited to '')
| -rw-r--r-- | gc/ptr_chck.c | 82 |
1 files changed, 42 insertions, 40 deletions
diff --git a/gc/ptr_chck.c b/gc/ptr_chck.c index f3451ee..af49d5f 100644 --- a/gc/ptr_chck.c +++ b/gc/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); } |