#define N_LOWTAG_BITS 3
#define LOWTAG_MASK ((1<<N_LOWTAG_BITS)-1)
-#define N_TYPE_BITS 8
-#define TYPE_MASK ((1<<N_TYPE_BITS)-1)
+#define N_WIDETAG_BITS 8
+#define WIDETAG_MASK ((1<<N_WIDETAG_BITS)-1)
-/* FIXME: There seems to be no reason that TypeOf, HeaderValue, CONS,
- * SYMBOL, and FDEFN can't be defined as (possibly inline) functions
- * instead of macros. */
+/* FIXME: Make HeaderValue, CONS, SYMBOL, and FDEFN into inline
+ * functions instead of macros. */
-#define TypeOf(obj) ((obj)&TYPE_MASK)
-#define HeaderValue(obj) ((unsigned long) ((obj)>>N_TYPE_BITS))
+#define HeaderValue(obj) ((unsigned long) ((obj) >> N_WIDETAG_BITS))
#define CONS(obj) ((struct cons *)((obj)-LIST_POINTER_LOWTAG))
#define SYMBOL(obj) ((struct symbol *)((obj)-OTHER_POINTER_LOWTAG))
* that SBCL runs on as of 0.6.7. If we port to the Alpha or some
* other non-32-bit machine we'll probably need real machine-dependent
* and OS-dependent definitions again. */
-#if ((defined alpha) && !(defined __linux__))
-#error No u32,s32 definitions for this platform. Write some.
-#else
-/* int happens to be 4 bytes on linux/alpha. long is longer. */
+/* even on alpha, int happens to be 4 bytes. long is longer. */
typedef unsigned int u32;
typedef signed int s32;
#define LOW_WORD(c) ((long)(c) & 0xFFFFFFFFL)
-#endif
+/* this is an integral type the same length as a machine pointer */
+typedef unsigned long pointer_sized_uint_t ;
typedef u32 lispobj;
static inline int
-lowtagof(lispobj obj) {
+lowtag_of(lispobj obj) {
return obj & LOWTAG_MASK;
}
+static inline int
+widetag_of(lispobj obj) {
+ return obj & WIDETAG_MASK;
+}
+
/* Is the Lisp object obj something with pointer nature (as opposed to
* e.g. a fixnum or character or unbound marker)? */
static inline int
/* Convert from a lispobj with type bits to a native (ordinary
* C/assembly) pointer to the beginning of the object. */
-static inline lispobj
+static inline lispobj *
native_pointer(lispobj obj)
{
- return obj & ~LOWTAG_MASK;
+ return (lispobj *) ((pointer_sized_uint_t) (obj & ~LOWTAG_MASK));
}
+/* inverse operation: create a suitably tagged lispobj from a native
+ * pointer or integer. Needs to be a macro due to the tedious C type
+ * system */
+#define make_lispobj(o,low_tag) ((lispobj)(LOW_WORD(o)|low_tag))
/* FIXME: There seems to be no reason that make_fixnum and fixnum_value
* can't be implemented as (possibly inline) functions. */
/* This only works for static symbols. */
/* FIXME: should be called StaticSymbolFunction, right? */
#define SymbolFunction(sym) \
- (((struct fdefn *)(SymbolValue(sym)-OTHER_POINTER_LOWTAG))->fun)
+ (((struct fdefn *)(native_pointer(SymbolValue(sym))))->fun)
/* KLUDGE: As far as I can tell there's no ANSI C way of saying
* "this function never returns". This is the way that you do it