/* Storage allocation and gc for GNU Emacs Lisp interpreter.
-Copyright (C) 1985-1986, 1988, 1993-1995, 1997-2013 Free Software
+Copyright (C) 1985-1986, 1988, 1993-1995, 1997-2014 Free Software
Foundation, Inc.
This file is part of GNU Emacs.
#if MAX_SAVE_STACK > 0
static char *stack_copy;
static ptrdiff_t stack_copy_size;
-#endif
+
+/* Copy to DEST a block of memory from SRC of size SIZE bytes,
+ avoiding any address sanitization. */
+
+static void * ATTRIBUTE_NO_SANITIZE_ADDRESS
+no_sanitize_memcpy (void *dest, void const *src, size_t size)
+{
+ if (! ADDRESS_SANITIZER)
+ return memcpy (dest, src, size);
+ else
+ {
+ size_t i;
+ char *d = dest;
+ char const *s = src;
+ for (i = 0; i < size; i++)
+ d[i] = s[i];
+ return dest;
+ }
+}
+
+#endif /* MAX_SAVE_STACK > 0 */
static Lisp_Object Qconses;
static Lisp_Object Qsymbols;
return memcpy (xmalloc (size), SSDATA (string), size);
}
+/* Assign to *PTR a copy of STRING, freeing any storage *PTR formerly
+ pointed to. If STRING is null, assign it without copying anything.
+ Allocate before freeing, to avoid a dangling pointer if allocation
+ fails. */
+
+void
+dupstring (char **ptr, char const *string)
+{
+ char *old = *ptr;
+ *ptr = string ? xstrdup (string) : 0;
+ xfree (old);
+}
+
+
/* Like putenv, but (1) use the equivalent of xmalloc and (2) the
argument is a const pointer. */
/* The entry point is lisp_align_malloc which returns blocks of at most
BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary. */
-#if !defined SYSTEM_MALLOC && !defined DOUG_LEA_MALLOC
-# define USE_ALIGNED_ALLOC 1
+/* Use aligned_alloc if it or a simple substitute is available.
+ Address sanitization breaks aligned allocation, as of gcc 4.8.2 and
+ clang 3.3 anyway. */
+
+#if ! ADDRESS_SANITIZER
+# if !defined SYSTEM_MALLOC && !defined DOUG_LEA_MALLOC
+# define USE_ALIGNED_ALLOC 1
/* Defined in gmalloc.c. */
void *aligned_alloc (size_t, size_t);
-#elif defined HAVE_ALIGNED_ALLOC
-# define USE_ALIGNED_ALLOC 1
-#elif defined HAVE_POSIX_MEMALIGN
-# define USE_ALIGNED_ALLOC 1
+# elif defined HAVE_ALIGNED_ALLOC
+# define USE_ALIGNED_ALLOC 1
+# elif defined HAVE_POSIX_MEMALIGN
+# define USE_ALIGNED_ALLOC 1
static void *
aligned_alloc (size_t alignment, size_t size)
{
void *p;
return posix_memalign (&p, alignment, size) == 0 ? p : 0;
}
+# endif
#endif
/* BLOCK_ALIGN has to be a power of 2. */
}
abase = ABLOCK_ABASE (free_ablock);
- ABLOCKS_BUSY (abase) =
- (struct ablocks *) (2 + (intptr_t) ABLOCKS_BUSY (abase));
+ ABLOCKS_BUSY (abase)
+ = (struct ablocks *) (2 + (intptr_t) ABLOCKS_BUSY (abase));
val = free_ablock;
free_ablock = free_ablock->x.next_free;
***********************************************************************/
/* Sometimes a vector's contents are merely a pointer internally used
- in vector allocation code. Usually you don't want to touch this. */
+ in vector allocation code. On the rare platforms where a null
+ pointer cannot be tagged, represent it with a Lisp 0.
+ Usually you don't want to touch this. */
+
+enum { TAGGABLE_NULL = (DATA_SEG_BITS & ~VALMASK) == 0 };
static struct Lisp_Vector *
next_vector (struct Lisp_Vector *v)
{
+ if (! TAGGABLE_NULL && EQ (v->contents[0], make_number (0)))
+ return 0;
return XUNTAG (v->contents[0], 0);
}
static void
set_next_vector (struct Lisp_Vector *v, struct Lisp_Vector *p)
{
- v->contents[0] = make_lisp_ptr (p, 0);
+ v->contents[0] = TAGGABLE_NULL || p ? make_lisp_ptr (p, 0) : make_number (0);
}
/* This value is balanced well enough to avoid too much internal overhead
static void
cleanup_vector (struct Lisp_Vector *vector)
{
- if (PSEUDOVECTOR_TYPEP (&vector->header, PVEC_FONT))
+ if (PSEUDOVECTOR_TYPEP (&vector->header, PVEC_FONT)
+ && ((vector->header.size & PSEUDOVECTOR_SIZE_MASK)
+ == FONT_OBJECT_MAX))
{
- ptrdiff_t size = vector->header.size & PSEUDOVECTOR_SIZE_MASK;
- Lisp_Object obj = make_lisp_ptr (vector, Lisp_Vectorlike);
+ struct font_driver *drv = ((struct font *) vector)->driver;
- if (size == FONT_OBJECT_MAX)
- font_close_object (obj);
-#ifdef HAVE_NS
- else if (size == FONT_ENTITY_MAX)
+ /* The font driver might sometimes be NULL, e.g. if Emacs was
+ interrupted before it had time to set it up. */
+ if (drv)
{
- struct font_entity *entity = (struct font_entity *) vector;
- if (entity->driver && entity->driver->free_entity)
- entity->driver->free_entity (obj);
+ /* Attempt to catch subtle bugs like Bug#16140. */
+ eassert (valid_font_driver (drv));
+ drv->close ((struct font *) vector);
}
-#endif /* HAVE_NS */
}
}
void
make_byte_code (struct Lisp_Vector *v)
{
- /* Don't allow the global zero_vector to become a byte code object. */
- eassert(0 < v->header.size);
+ /* Don't allow the global zero_vector to become a byte code object. */
+ eassert (0 < v->header.size);
+
if (v->header.size > 1 && STRINGP (v->contents[1])
&& STRING_MULTIBYTE (v->contents[1]))
/* BYTECODE-STRING must have been produced by Emacs 20.2 or the
static struct symbol_block *symbol_block;
static int symbol_block_index = SYMBOL_BLOCK_SIZE;
+/* Pointer to the first symbol_block that contains pinned symbols.
+ Tests for 24.4 showed that at dump-time, Emacs contains about 15K symbols,
+ 10K of which are pinned (and all but 250 of them are interned in obarray),
+ whereas a "typical session" has in the order of 30K symbols.
+ `symbol_block_pinned' lets mark_pinned_symbols scan only 15K symbols rather
+ than 30K to find the 10K symbols we need to mark. */
+static struct symbol_block *symbol_block_pinned;
/* List of free symbols. */
SET_SYMBOL_VAL (p, Qunbound);
set_symbol_function (val, Qnil);
set_symbol_next (val, NULL);
- p->gcmarkbit = 0;
+ p->gcmarkbit = false;
p->interned = SYMBOL_UNINTERNED;
p->constant = 0;
- p->declared_special = 0;
+ p->declared_special = false;
+ p->pinned = false;
consing_since_gc += sizeof (struct Lisp_Symbol);
symbols_consed++;
total_free_symbols--;
/* Mark Lisp objects referenced from the address range START+OFFSET..END
or END+OFFSET..START. */
-static void
+static void ATTRIBUTE_NO_SANITIZE_ADDRESS
mark_memory (void *start, void *end)
-#if defined (__clang__) && defined (__has_feature)
-#if __has_feature(address_sanitizer)
- /* Do not allow -faddress-sanitizer to check this function, since it
- crosses the function stack boundary, and thus would yield many
- false positives. */
- __attribute__((no_address_safety_analysis))
-#endif
-#endif
{
void **pp;
int i;
return string;
}
+static Lisp_Object purecopy (Lisp_Object obj);
+
/* Return a cons allocated from pure space. Give it pure copies
of CAR as car and CDR as cdr. */
Lisp_Object new;
struct Lisp_Cons *p = pure_alloc (sizeof *p, Lisp_Cons);
XSETCONS (new, p);
- XSETCAR (new, Fpurecopy (car));
- XSETCDR (new, Fpurecopy (cdr));
+ XSETCAR (new, purecopy (car));
+ XSETCDR (new, purecopy (cdr));
return new;
}
{
if (NILP (Vpurify_flag))
return obj;
-
- if (PURE_POINTER_P (XPNTR (obj)))
+ else if (MARKERP (obj) || OVERLAYP (obj)
+ || HASH_TABLE_P (obj) || SYMBOLP (obj))
+ /* Can't purify those. */
return obj;
+ else
+ return purecopy (obj);
+}
+
+static Lisp_Object
+purecopy (Lisp_Object obj)
+{
+ if (PURE_POINTER_P (XPNTR (obj)) || INTEGERP (obj) || SUBRP (obj))
+ return obj; /* Already pure. */
if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
{
size &= PSEUDOVECTOR_SIZE_MASK;
vec = XVECTOR (make_pure_vector (size));
for (i = 0; i < size; i++)
- vec->contents[i] = Fpurecopy (AREF (obj, i));
+ vec->contents[i] = purecopy (AREF (obj, i));
if (COMPILEDP (obj))
{
XSETPVECTYPE (vec, PVEC_COMPILED);
else
XSETVECTOR (obj, vec);
}
- else if (MARKERP (obj))
- error ("Attempt to copy a marker to pure storage");
+ else if (SYMBOLP (obj))
+ {
+ if (!XSYMBOL (obj)->pinned)
+ { /* We can't purify them, but they appear in many pure objects.
+ Mark them as `pinned' so we know to mark them at every GC cycle. */
+ XSYMBOL (obj)->pinned = true;
+ symbol_block_pinned = symbol_block;
+ }
+ return obj;
+ }
else
- /* Not purified, don't hash-cons. */
- return obj;
+ {
+ Lisp_Object args[2];
+ args[0] = build_pure_c_string ("Don't know how to purify: %S");
+ args[1] = obj;
+ Fsignal (Qerror, (Fcons (Fformat (2, args), Qnil)));
+ }
if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
Fputhash (obj, obj, Vpurify_flag);
#ifdef HAVE_WINDOW_SYSTEM
+/* This code has a few issues on MS-Windows, see Bug#15876 and Bug#16140. */
+
+#if !defined (HAVE_NTGUI)
+
/* Remove unmarked font-spec and font-entity objects from ENTRY, which is
(DRIVER-TYPE NUM-FRAMES FONT-CACHE-DATA ...), and return changed entry. */
return entry;
}
+#endif /* not HAVE_NTGUI */
+
/* Compact font caches on all terminals and mark
everything which is still here after compaction. */
for (t = terminal_list; t; t = t->next_terminal)
{
Lisp_Object cache = TERMINAL_FONT_CACHE (t);
-
+#if !defined (HAVE_NTGUI)
if (CONSP (cache))
{
Lisp_Object entry;
for (entry = XCDR (cache); CONSP (entry); entry = XCDR (entry))
XSETCAR (entry, compact_font_cache_entry (XCAR (entry)));
}
+#endif /* not HAVE_NTGUI */
mark_object (cache);
}
}
return list;
}
+static void
+mark_pinned_symbols (void)
+{
+ struct symbol_block *sblk;
+ int lim = (symbol_block_pinned == symbol_block
+ ? symbol_block_index : SYMBOL_BLOCK_SIZE);
+
+ for (sblk = symbol_block_pinned; sblk; sblk = sblk->next)
+ {
+ union aligned_Lisp_Symbol *sym = sblk->symbols, *end = sym + lim;
+ for (; sym < end; ++sym)
+ if (sym->s.pinned)
+ mark_object (make_lisp_ptr (&sym->s, Lisp_Symbol));
+
+ lim = SYMBOL_BLOCK_SIZE;
+ }
+}
+
DEFUN ("garbage-collect", Fgarbage_collect, Sgarbage_collect, 0, 0, "",
doc: /* Reclaim storage for Lisp objects no longer needed.
Garbage collection happens automatically if you cons more than
stack_copy = xrealloc (stack_copy, stack_size);
stack_copy_size = stack_size;
}
- memcpy (stack_copy, stack, stack_size);
+ no_sanitize_memcpy (stack_copy, stack, stack_size);
}
}
#endif /* MAX_SAVE_STACK > 0 */
for (i = 0; i < staticidx; i++)
mark_object (*staticvec[i]);
+ mark_pinned_symbols ();
mark_specpdl ();
mark_terminals ();
mark_kboards ();
for (; sym < end; ++sym)
{
- /* Check if the symbol was created during loadup. In such a case
- it might be pointed to by pure bytecode which we don't trace,
- so we conservatively assume that it is live. */
- bool pure_p = PURE_POINTER_P (XSTRING (sym->s.name));
-
- if (!sym->s.gcmarkbit && !pure_p)
+ if (!sym->s.gcmarkbit)
{
if (sym->s.redirect == SYMBOL_LOCALIZED)
xfree (SYMBOL_BLV (&sym->s));
else
{
++num_used;
- if (!pure_p)
- eassert (!STRING_MARKED_P (XSTRING (sym->s.name)));
+ eassert (!STRING_MARKED_P (XSTRING (sym->s.name)));
sym->s.gcmarkbit = 0;
}
}
enum CHECK_LISP_OBJECT_TYPE CHECK_LISP_OBJECT_TYPE;
enum DEFAULT_HASH_SIZE DEFAULT_HASH_SIZE;
enum enum_USE_LSB_TAG enum_USE_LSB_TAG;
- enum FLOAT_TO_STRING_BUFSIZE FLOAT_TO_STRING_BUFSIZE;
enum Lisp_Bits Lisp_Bits;
enum Lisp_Compiled Lisp_Compiled;
enum maxargs maxargs;