dbg_mlc.c

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        if (clobbered != 0) {
          if (((oh *)base) -> oh_sz == GC_size(base)) {
            GC_err_printf(
                  "GC_debug_free: found previously deallocated (?) object at ");
          } else {
            GC_err_printf("GC_debug_free: found smashed location at ");
          }
          GC_print_smashed_obj(p, clobbered);
        }
        /* Invalidate size */
        ((oh *)base) -> oh_sz = GC_size(base);
#     endif /* SHORT_DBG_HDRS */
    }
    if (GC_find_leak) {
        GC_free(base);
    } else {
	hdr * hhdr = HDR(p);
	GC_bool uncollectable = FALSE;

        if (hhdr ->  hb_obj_kind == UNCOLLECTABLE) {
	    uncollectable = TRUE;
	}
#	ifdef ATOMIC_UNCOLLECTABLE
	    if (hhdr ->  hb_obj_kind == AUNCOLLECTABLE) {
		    uncollectable = TRUE;
	    }
#	endif
	if (uncollectable) {
	    GC_free(base);
	} else {
	    size_t i;
	    size_t obj_sz = BYTES_TO_WORDS(hhdr -> hb_sz - sizeof(oh));

	    for (i = 0; i < obj_sz; ++i) ((word *)p)[i] = 0xdeadbeef;
	    GC_ASSERT((word *)p + i == (word *)(base + hhdr -> hb_sz));
	}
    } /* !GC_find_leak */
}

#ifdef THREADS

extern void GC_free_inner(void * p);

/* Used internally; we assume it's called correctly.	*/
void GC_debug_free_inner(void * p)
{
    GC_free_inner(GC_base(p));
}
#endif

void * GC_debug_realloc(void * p, size_t lb, GC_EXTRA_PARAMS)
{
    void * base = GC_base(p);
    ptr_t clobbered;
    void * result;
    size_t copy_sz = lb;
    size_t old_sz;
    hdr * hhdr;
    
    if (p == 0) return(GC_debug_malloc(lb, OPT_RA s, i));
    if (base == 0) {
        GC_err_printf("Attempt to reallocate invalid pointer %p\n", p);
        ABORT("realloc(invalid pointer)");
    }
    if ((ptr_t)p - (ptr_t)base != sizeof(oh)) {
        GC_err_printf(
        	"GC_debug_realloc called on pointer %p wo debugging info\n", p);
        return(GC_realloc(p, lb));
    }
    hhdr = HDR(base);
    switch (hhdr -> hb_obj_kind) {
#    ifdef STUBBORN_ALLOC
      case STUBBORN:
        result = GC_debug_malloc_stubborn(lb, OPT_RA s, i);
        break;
#    endif
      case NORMAL:
        result = GC_debug_malloc(lb, OPT_RA s, i);
        break;
      case PTRFREE:
        result = GC_debug_malloc_atomic(lb, OPT_RA s, i);
        break;
      case UNCOLLECTABLE:
	result = GC_debug_malloc_uncollectable(lb, OPT_RA s, i);
 	break;
#    ifdef ATOMIC_UNCOLLECTABLE
      case AUNCOLLECTABLE:
	result = GC_debug_malloc_atomic_uncollectable(lb, OPT_RA s, i);
	break;
#    endif
      default:
        GC_err_printf("GC_debug_realloc: encountered bad kind\n");
        ABORT("bad kind");
    }
#   ifdef SHORT_DBG_HDRS
      old_sz = GC_size(base) - sizeof(oh);
#   else
      clobbered = GC_check_annotated_obj((oh *)base);
      if (clobbered != 0) {
        GC_err_printf("GC_debug_realloc: found smashed location at ");
        GC_print_smashed_obj(p, clobbered);
      }
      old_sz = ((oh *)base) -> oh_sz;
#   endif
    if (old_sz < copy_sz) copy_sz = old_sz;
    if (result == 0) return(0);
    BCOPY(p, result,  copy_sz);
    GC_debug_free(p);
    return(result);
}

#ifndef SHORT_DBG_HDRS

/* List of smashed objects.  We defer printing these, since we can't	*/
/* always print them nicely with the allocation lock held.		*/
/* We put them here instead of in GC_arrays, since it may be useful to	*/
/* be able to look at them with the debugger.				*/
#define MAX_SMASHED 20
ptr_t GC_smashed[MAX_SMASHED];
unsigned GC_n_smashed = 0;

void GC_add_smashed(ptr_t smashed)
{
    GC_ASSERT(GC_is_marked(GC_base(smashed)));
    GC_smashed[GC_n_smashed] = smashed;
    if (GC_n_smashed < MAX_SMASHED - 1) ++GC_n_smashed;
      /* In case of overflow, we keep the first MAX_SMASHED-1	*/
      /* entries plus the last one.				*/
    GC_have_errors = TRUE;
}

/* Print all objects on the list.  Clear the list.	*/
void GC_print_all_smashed_proc(void)
{
    unsigned i;

    GC_ASSERT(I_DONT_HOLD_LOCK());
    if (GC_n_smashed == 0) return;
    GC_err_printf("GC_check_heap_block: found smashed heap objects:\n");
    for (i = 0; i < GC_n_smashed; ++i) {
        GC_print_smashed_obj(GC_base(GC_smashed[i]), GC_smashed[i]);
	GC_smashed[i] = 0;
    }
    GC_n_smashed = 0;
}

/* Check all marked objects in the given block for validity   	*/
/* Avoid GC_apply_to_each_object for performance reasons.	*/
/*ARGSUSED*/
void GC_check_heap_block(struct hblk *hbp, word dummy)
{
    struct hblkhdr * hhdr = HDR(hbp);
    size_t sz = hhdr -> hb_sz;
    size_t bit_no;
    char *p, *plim;
    
    p = hbp->hb_body;
    bit_no = 0;
    if (sz > MAXOBJBYTES) {
	plim = p;
    } else {
    	plim = hbp->hb_body + HBLKSIZE - sz;
    }
    /* go through all words in block */
	while( p <= plim ) {
	    if( mark_bit_from_hdr(hhdr, bit_no)
	        && GC_HAS_DEBUG_INFO((ptr_t)p)) {
	        ptr_t clobbered = GC_check_annotated_obj((oh *)p);
	        
	        if (clobbered != 0) GC_add_smashed(clobbered);
	    }
	    bit_no += MARK_BIT_OFFSET(sz);
	    p += sz;
	}
}


/* This assumes that all accessible objects are marked, and that	*/
/* I hold the allocation lock.	Normally called by collector.		*/
void GC_check_heap_proc(void)
{
#   ifndef SMALL_CONFIG
      /* Ignore gcc no effect warning on the following.		*/
      GC_STATIC_ASSERT((sizeof(oh) & (GRANULE_BYTES - 1)) == 0);
      /* FIXME: Should we check for twice that alignment?	*/
#   endif
    GC_apply_to_all_blocks(GC_check_heap_block, (word)0);
}

#endif /* !SHORT_DBG_HDRS */

struct closure {
    GC_finalization_proc cl_fn;
    void * cl_data;
};

void * GC_make_closure(GC_finalization_proc fn, void * data)
{
    struct closure * result =
#   ifdef DBG_HDRS_ALL
      (struct closure *) GC_debug_malloc(sizeof (struct closure),
				         GC_EXTRAS);
#   else
      (struct closure *) GC_malloc(sizeof (struct closure));
#   endif
    
    result -> cl_fn = fn;
    result -> cl_data = data;
    return((void *)result);
}

void GC_debug_invoke_finalizer(void * obj, void * data)
{
    register struct closure * cl = (struct closure *) data;
    
    (*(cl -> cl_fn))((void *)((char *)obj + sizeof(oh)), cl -> cl_data);
} 

/* Set ofn and ocd to reflect the values we got back.	*/
static void store_old (void *obj, GC_finalization_proc my_old_fn,
		       struct closure *my_old_cd, GC_finalization_proc *ofn,
		       void **ocd)
{
    if (0 != my_old_fn) {
      if (my_old_fn != GC_debug_invoke_finalizer) {
        GC_err_printf("Debuggable object at %p had non-debug finalizer.\n",
		      obj);
        /* This should probably be fatal. */
      } else {
        if (ofn) *ofn = my_old_cd -> cl_fn;
        if (ocd) *ocd = my_old_cd -> cl_data;
      }
    } else {
      if (ofn) *ofn = 0;
      if (ocd) *ocd = 0;
    }
}

void GC_debug_register_finalizer(void * obj, GC_finalization_proc fn,
    				 void * cd, GC_finalization_proc *ofn,
				 void * *ocd)
{
    GC_finalization_proc my_old_fn;
    void * my_old_cd;
    ptr_t base = GC_base(obj);
    if (0 == base) return;
    if ((ptr_t)obj - base != sizeof(oh)) {
        GC_err_printf(
	    "GC_debug_register_finalizer called with non-base-pointer %p\n",
	    obj);
    }
    if (0 == fn) {
      GC_register_finalizer(base, 0, 0, &my_old_fn, &my_old_cd);
    } else {
      GC_register_finalizer(base, GC_debug_invoke_finalizer,
    			    GC_make_closure(fn,cd), &my_old_fn, &my_old_cd);
    }
    store_old(obj, my_old_fn, (struct closure *)my_old_cd, ofn, ocd);
}

void GC_debug_register_finalizer_no_order
    				    (void * obj, GC_finalization_proc fn,
    				     void * cd, GC_finalization_proc *ofn,
				     void * *ocd)
{
    GC_finalization_proc my_old_fn;
    void * my_old_cd;
    ptr_t base = GC_base(obj);
    if (0 == base) return;
    if ((ptr_t)obj - base != sizeof(oh)) {
        GC_err_printf(
	  "GC_debug_register_finalizer_no_order called with "
	  "non-base-pointer %p\n",
	  obj);
    }
    if (0 == fn) {
      GC_register_finalizer_no_order(base, 0, 0, &my_old_fn, &my_old_cd);
    } else {
      GC_register_finalizer_no_order(base, GC_debug_invoke_finalizer,
    			    	     GC_make_closure(fn,cd), &my_old_fn,
				     &my_old_cd);
    }
    store_old(obj, my_old_fn, (struct closure *)my_old_cd, ofn, ocd);
}

void GC_debug_register_finalizer_unreachable
    				    (void * obj, GC_finalization_proc fn,
    				     void * cd, GC_finalization_proc *ofn,
				     void * *ocd)
{
    GC_finalization_proc my_old_fn;
    void * my_old_cd;
    ptr_t base = GC_base(obj);
    if (0 == base) return;
    if ((ptr_t)obj - base != sizeof(oh)) {
        GC_err_printf(
	    "GC_debug_register_finalizer_unreachable called with "
	    "non-base-pointer %p\n",
	    obj);
    }
    if (0 == fn) {
      GC_register_finalizer_unreachable(base, 0, 0, &my_old_fn, &my_old_cd);
    } else {
      GC_register_finalizer_unreachable(base, GC_debug_invoke_finalizer,
    			    	        GC_make_closure(fn,cd), &my_old_fn,
				        &my_old_cd);
    }
    store_old(obj, my_old_fn, (struct closure *)my_old_cd, ofn, ocd);
}

void GC_debug_register_finalizer_ignore_self
    				    (void * obj, GC_finalization_proc fn,
    				     void * cd, GC_finalization_proc *ofn,
				     void * *ocd)
{
    GC_finalization_proc my_old_fn;
    void * my_old_cd;
    ptr_t base = GC_base(obj);
    if (0 == base) return;
    if ((ptr_t)obj - base != sizeof(oh)) {
        GC_err_printf(
	    "GC_debug_register_finalizer_ignore_self called with "
	    "non-base-pointer %p\n", obj);
    }
    if (0 == fn) {
      GC_register_finalizer_ignore_self(base, 0, 0, &my_old_fn, &my_old_cd);
    } else {
      GC_register_finalizer_ignore_self(base, GC_debug_invoke_finalizer,
    			    	     GC_make_closure(fn,cd), &my_old_fn,
				     &my_old_cd);
    }
    store_old(obj, my_old_fn, (struct closure *)my_old_cd, ofn, ocd);
}

#ifdef GC_ADD_CALLER
# define RA GC_RETURN_ADDR,
#else
# define RA
#endif

void * GC_debug_malloc_replacement(size_t lb)
{
    return GC_debug_malloc(lb, RA "unknown", 0);
}

void * GC_debug_realloc_replacement(void *p, size_t lb)
{
    return GC_debug_realloc(p, lb, RA "unknown", 0);
}