diff options
Diffstat (limited to 'gc/ptr_chck.c')
-rw-r--r-- | gc/ptr_chck.c | 328 |
1 files changed, 0 insertions, 328 deletions
diff --git a/gc/ptr_chck.c b/gc/ptr_chck.c deleted file mode 100644 index af49d5f..0000000 --- a/gc/ptr_chck.c +++ /dev/null @@ -1,328 +0,0 @@ -/* - * 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. - */ - -/* - * 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) -#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 + 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 { - 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. */ - /* 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 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. */ -#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); - if (GC_all_interior_pointers) { - while (IS_FORWARDING_ADDR_OR_NIL(hhdr)) { - h = FORWARDED_ADDR(h, hhdr); - hhdr = HDR(h); - } - } - 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(MSWINCE) || 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 & GC_DS_TAGS) { - case GC_DS_LENGTH: - if ((word)((ptr_t)p - (ptr_t)base) > (word)descr) goto fail; - break; - 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 GC_DS_PROC: - /* We could try to decipher this partially. */ - /* For now we just punt. */ - break; - 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); - } -# 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); - - if (!GC_all_interior_pointers) { - (void) GC_is_valid_displacement(result); - } - 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); - - if (!GC_all_interior_pointers) { - (void) GC_is_valid_displacement(result); - } - *p = result; - return(initial); -} |