#endif
#endif /* ENABLE_CHECKING */
\f
-/* Use the configure flag --enable-use-lisp-union-type to make
- Lisp_Object use a union type instead of the default int. The flag
- causes USE_LISP_UNION_TYPE to be defined. */
+/* Use the configure flag --enable-check-lisp-object-type to make
+ Lisp_Object use a struct type instead of the default int. The flag
+ causes CHECK_LISP_OBJECT_TYPE to be defined. */
/***** Select the tagging scheme. *****/
-/* There are basically two options that control the tagging scheme:
- - USE_LISP_UNION_TYPE says that Lisp_Object should be a union instead
- of an integer.
+/* The following option controls the tagging scheme:
- USE_LSB_TAG means that we can assume the least 3 bits of pointers are
always 0, and we can thus use them to hold tag bits, without
restricting our addressing space.
e.g -2^28..2^28-1 to -2^29..2^29-1. */
#define USE_2_TAGS_FOR_INTS
-/* Making it work for the union case is too much trouble. */
-#ifdef USE_LISP_UNION_TYPE
-# undef USE_2_TAGS_FOR_INTS
-#endif
-
/* This is the set of Lisp data types. */
#if !defined USE_2_TAGS_FOR_INTS
Lisp_Fwd_Kboard_Obj, /* Fwd to a Lisp_Object field of kboards. */
};
-#ifdef USE_LISP_UNION_TYPE
+#ifdef CHECK_LISP_OBJECT_TYPE
-typedef
-union Lisp_Object
- {
- /* Used for comparing two Lisp_Objects;
- also, positive integers can be accessed fast this way. */
- EMACS_INT i;
-
- struct
- {
- /* Use explicit signed, the signedness of a bit-field of type
- int is implementation defined. */
- signed EMACS_INT val : VALBITS;
- ENUM_BF (Lisp_Type) type : GCTYPEBITS;
- } s;
- struct
- {
- EMACS_UINT val : VALBITS;
- ENUM_BF (Lisp_Type) type : GCTYPEBITS;
- } u;
- }
-Lisp_Object;
+typedef struct { EMACS_INT i; } Lisp_Object;
+
+#define XLI(o) (o).i
+static inline Lisp_Object
+XIL (EMACS_INT i)
+{
+ Lisp_Object o = { i };
+ return o;
+}
static inline Lisp_Object
LISP_MAKE_RVALUE (Lisp_Object o)
#define LISP_INITIALLY_ZERO {0}
-#else /* USE_LISP_UNION_TYPE */
+#else /* CHECK_LISP_OBJECT_TYPE */
-/* If union type is not wanted, define Lisp_Object as just a number. */
+/* If a struct type is not wanted, define Lisp_Object as just a number. */
typedef EMACS_INT Lisp_Object;
+#define XLI(o) (o)
+#define XIL(i) (i)
#define LISP_MAKE_RVALUE(o) (0+(o))
#define LISP_INITIALLY_ZERO 0
-#endif /* USE_LISP_UNION_TYPE */
+#endif /* CHECK_LISP_OBJECT_TYPE */
/* In the size word of a vector, this bit means the vector has been marked. */
For example, if tem is a Lisp_Object whose type is Lisp_Cons,
XCONS (tem) is the struct Lisp_Cons * pointing to the memory for that cons. */
-#ifndef USE_LISP_UNION_TYPE
-
/* Return a perfect hash of the Lisp_Object representation. */
-#define XHASH(a) (a)
+#define XHASH(a) XLI(a)
#if USE_LSB_TAG
#define TYPEMASK ((((EMACS_INT) 1) << GCTYPEBITS) - 1)
-#define XTYPE(a) ((enum Lisp_Type) ((a) & TYPEMASK))
+#define XTYPE(a) ((enum Lisp_Type) (XLI(a) & TYPEMASK))
#ifdef USE_2_TAGS_FOR_INTS
-# define XINT(a) (((EMACS_INT) (a)) >> (GCTYPEBITS - 1))
-# define XUINT(a) (((EMACS_UINT) (a)) >> (GCTYPEBITS - 1))
-# define make_number(N) (((EMACS_INT) (N)) << (GCTYPEBITS - 1))
+# define XINT(a) (((EMACS_INT) XLI(a)) >> (GCTYPEBITS - 1))
+# define XUINT(a) (((EMACS_UINT) XLI(a)) >> (GCTYPEBITS - 1))
+# define make_number(N) XIL(((EMACS_INT) (N)) << (GCTYPEBITS - 1))
#else
-# define XINT(a) (((EMACS_INT) (a)) >> GCTYPEBITS)
-# define XUINT(a) (((EMACS_UINT) (a)) >> GCTYPEBITS)
-# define make_number(N) (((EMACS_INT) (N)) << GCTYPEBITS)
+# define XINT(a) (((EMACS_INT) XLI(a)) >> GCTYPEBITS)
+# define XUINT(a) (((EMACS_UINT) XLI(a)) >> GCTYPEBITS)
+# define make_number(N) XIL(((EMACS_INT) (N)) << GCTYPEBITS)
#endif
-#define XSET(var, type, ptr) \
- (eassert (XTYPE ((intptr_t) (ptr)) == 0), /* Check alignment. */ \
- (var) = (type) | (intptr_t) (ptr))
+#define XSET(var, type, ptr) \
+ (eassert (XTYPE (XIL((intptr_t) (ptr))) == 0), /* Check alignment. */ \
+ (var) = XIL((type) | (intptr_t) (ptr)))
-#define XPNTR(a) ((intptr_t) ((a) & ~TYPEMASK))
-#define XUNTAG(a, type) ((intptr_t) ((a) - (type)))
+#define XPNTR(a) ((intptr_t) (XLI(a) & ~TYPEMASK))
+#define XUNTAG(a, type) ((intptr_t) (XLI(a) - (type)))
#else /* not USE_LSB_TAG */
(doing the result of the below & ((1 << (GCTYPE + 1)) - 1) would work
on all machines, but would penalize machines which don't need it)
*/
-#define XTYPE(a) ((enum Lisp_Type) (((EMACS_UINT) (a)) >> VALBITS))
+#define XTYPE(a) ((enum Lisp_Type) (((EMACS_UINT) XLI(a)) >> VALBITS))
/* For integers known to be positive, XFASTINT provides fast retrieval
and XSETFASTINT provides fast storage. This takes advantage of the
fact that Lisp_Int is 0. */
-#define XFASTINT(a) ((a) + 0)
-#define XSETFASTINT(a, b) ((a) = (b))
+#define XFASTINT(a) (XLI(a) + 0)
+#define XSETFASTINT(a, b) ((a) = XIL(b))
/* Extract the value of a Lisp_Object as a (un)signed integer. */
#ifdef USE_2_TAGS_FOR_INTS
-# define XINT(a) ((((EMACS_INT) (a)) << (GCTYPEBITS - 1)) >> (GCTYPEBITS - 1))
-# define XUINT(a) ((EMACS_UINT) ((a) & (1 + (VALMASK << 1))))
-# define make_number(N) ((((EMACS_INT) (N)) & (1 + (VALMASK << 1))))
+# define XINT(a) ((((EMACS_INT) XLI(a)) << (GCTYPEBITS - 1)) >> (GCTYPEBITS - 1))
+# define XUINT(a) ((EMACS_UINT) (XLI(a) & (1 + (VALMASK << 1))))
+# define make_number(N) XIL((((EMACS_INT) (N)) & (1 + (VALMASK << 1))))
#else
-# define XINT(a) ((((EMACS_INT) (a)) << (BITS_PER_EMACS_INT - VALBITS)) \
- >> (BITS_PER_EMACS_INT - VALBITS))
-# define XUINT(a) ((EMACS_UINT) ((a) & VALMASK))
+# define XINT(a) ((((EMACS_INT) XLI(a)) << (BITS_PER_EMACS_INT - VALBITS)) \
+ >> (BITS_PER_EMACS_INT - VALBITS))
+# define XUINT(a) ((EMACS_UINT) (XLI(a) & VALMASK))
# define make_number(N) \
- ((((EMACS_INT) (N)) & VALMASK) | ((EMACS_INT) Lisp_Int) << VALBITS)
+ XIL((((EMACS_INT) (N)) & VALMASK) | ((EMACS_INT) Lisp_Int) << VALBITS)
#endif
#define XSET(var, type, ptr) \
- ((var) = ((EMACS_INT) ((EMACS_UINT) (type) << VALBITS) \
- + ((intptr_t) (ptr) & VALMASK)))
+ ((var) = XIL((EMACS_INT) ((EMACS_UINT) (type) << VALBITS) \
+ + ((intptr_t) (ptr) & VALMASK)))
#ifdef DATA_SEG_BITS
/* DATA_SEG_BITS forces extra bits to be or'd in with any pointers
which were stored in a Lisp_Object */
-#define XPNTR(a) ((uintptr_t) (((a) & VALMASK)) | DATA_SEG_BITS))
+#define XPNTR(a) ((uintptr_t) ((XLI(a) & VALMASK)) | DATA_SEG_BITS))
#else
-#define XPNTR(a) ((uintptr_t) ((a) & VALMASK))
+#define XPNTR(a) ((uintptr_t) (XLI(a) & VALMASK))
#endif
#endif /* not USE_LSB_TAG */
-#else /* USE_LISP_UNION_TYPE */
-
-#ifdef USE_2_TAGS_FOR_INTS
-# error "USE_2_TAGS_FOR_INTS is not supported with USE_LISP_UNION_TYPE"
-#endif
-
-#define XHASH(a) ((a).i)
-#define XTYPE(a) ((enum Lisp_Type) (a).u.type)
-#define XINT(a) ((EMACS_INT) (a).s.val)
-#define XUINT(a) ((EMACS_UINT) (a).u.val)
-
-#if USE_LSB_TAG
-
-# define XSET(var, vartype, ptr) \
- (eassert (((uintptr_t) (ptr) & ((1 << GCTYPEBITS) - 1)) == 0), \
- (var).u.val = (uintptr_t) (ptr) >> GCTYPEBITS, \
- (var).u.type = (vartype))
-
-/* Some versions of gcc seem to consider the bitfield width when issuing
- the "cast to pointer from integer of different size" warning, so the
- cast is here to widen the value back to its natural size. */
-# define XPNTR(v) ((intptr_t) (v).s.val << GCTYPEBITS)
-
-#else /* !USE_LSB_TAG */
-
-# define XSET(var, vartype, ptr) \
- ((var).s.val = (intptr_t) (ptr), (var).s.type = (vartype))
-
-#ifdef DATA_SEG_BITS
-/* DATA_SEG_BITS forces extra bits to be or'd in with any pointers
- which were stored in a Lisp_Object */
-#define XPNTR(a) ((intptr_t) (XUINT (a) | DATA_SEG_BITS))
-#else
-#define XPNTR(a) ((intptr_t) XUINT (a))
-#endif
-
-#endif /* !USE_LSB_TAG */
-
-static inline Lisp_Object
-make_number (EMACS_INT n)
-{
- Lisp_Object o;
- o.s.val = n;
- o.s.type = Lisp_Int;
- return o;
-}
-
-#endif /* USE_LISP_UNION_TYPE */
-
/* For integers known to be positive, XFASTINT sometimes provides
faster retrieval and XSETFASTINT provides faster storage.
If not, fallback on the non-accelerated path. */
HCoop / bpt / emacs.git / blobdiff