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-rw-r--r--gc/ptr_chck.c328
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);
-}