(in-package "SB!VM")
-;;; FIXME: It's clever using :SUFFIX -LOWTAG for these things, but
-;;; it's a pain for people just learning to find their way around the
-;;; code who want to use lexical search to figure out where things
-;;; like EVEN-FIXNUM-LOWTAG are defined. Remove the :SUFFIXes and just
-;;; expand out the full names. Or even define them in DEF
-;;; EVEN-FIXNUM-LOWTAG style so searches like
-;;; 'def.*even-fixnum-lowtag' can find them.
-
;;; Tags for the main low-level types are stored in the low n (usually three)
;;; bits to identify the type of a machine word. Certain constraints
;;; apply:
;;; might easily be more, since these values have stayed highly
;;; constrained for more than a decade, an inviting target for
;;; inventive abstraction-phobic maintainers.:-)
+;;;
+;;; Another way to look at lowtags is that there is no one lowtag
+;;; length. On 32-bit platforms, fixnums and other-immediates have a
+;;; lowtag length of two bits, and pointers have a lowtag length of
+;;; three bits. On 64-bit platforms, fixnums and pointers gain an
+;;; extra bit, and six "pad" lowtags waste the extra encoding space so
+;;; obtained.
+;;;
+;;; x00 -- fixnum
+;;; x10 -- other-immediate
+;;; 001 -- instance-pointer
+;;; 011 -- list-pointer
+;;; 101 -- fun-pointer
+;;; 111 -- other-pointer
+;;;
+;;; If you change the tag layout, check the various functions in
+;;; src/runtime/runtime.h to see if they need to be updated, along
+;;; with print_obj() in src/runtime/print.c, possibly gc_init_tables()
+;;; in src/runtime/gc-common-c and possibly the code in src/code/room.
(eval-when (:compile-toplevel :load-toplevel :execute)
;; The EVAL-WHEN is necessary (at least for Lispworks), because the
;; second DEFENUM uses the value of OTHER-IMMEDIATE-0-LOWTAG, which is
;; defined in the first DEFENUM. -- AL 20000216
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- (defenum (:suffix -lowtag)
- even-fixnum
- instance-pointer
- other-immediate-0
- pad0 pad1 pad2
- other-immediate-1
- list-pointer
- odd-fixnum
- fun-pointer
- other-immediate-2
- pad3 pad4 pad5
- other-immediate-3
- other-pointer)
+ (defenum ()
+ even-fixnum-lowtag
+ other-immediate-0-lowtag
+ pad0-lowtag
+ instance-pointer-lowtag
+ pad1-lowtag
+ other-immediate-1-lowtag
+ pad2-lowtag
+ list-pointer-lowtag
+ odd-fixnum-lowtag
+ other-immediate-2-lowtag
+ pad3-lowtag
+ fun-pointer-lowtag
+ pad4-lowtag
+ other-immediate-3-lowtag
+ pad5-lowtag
+ other-pointer-lowtag)
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- (defenum (:suffix -lowtag)
- even-fixnum
- instance-pointer
- other-immediate-0
- list-pointer
- odd-fixnum
- fun-pointer
- other-immediate-1
- other-pointer))
+ (defenum ()
+ even-fixnum-lowtag
+ instance-pointer-lowtag
+ other-immediate-0-lowtag
+ list-pointer-lowtag
+ odd-fixnum-lowtag
+ fun-pointer-lowtag
+ other-immediate-1-lowtag
+ other-pointer-lowtag))
(def!constant nil-value
(+ static-space-start n-word-bytes other-pointer-lowtag))
+(defconstant-eqx fixnum-lowtags
+ #.(let ((fixtags nil))
+ (do-external-symbols (sym "SB!VM")
+ (let* ((name (symbol-name sym))
+ (len (length name)))
+ (when (and (boundp sym)
+ (integerp (symbol-value sym))
+ (> len 7)
+ (string= name "-LOWTAG" :start1 (- len 7))
+ (zerop (logand (symbol-value sym) fixnum-tag-mask)))
+ (push sym fixtags))))
+ `',(sort fixtags #'string< :key #'symbol-name))
+ #'equal)
+
;;; the heap types, stored in 8 bits of the header of an object on the
;;; heap, to identify the type of the heap object (which'll be at
;;; least two machine words, often more)
;;; JNE tag, label
;;;
;;; rather than two separate tests and jumps
-(defenum (:suffix -widetag
- ;; The first widetag must be greater than SB!VM:LOWTAG-LIMIT
+(defenum (;; The first widetag must be greater than SB!VM:LOWTAG-LIMIT
;; otherwise code in generic/early-type-vops will suffer
;; a long, horrible death. --njf, 2004-08-09
:start (+ (ash 1 n-lowtag-bits) other-immediate-0-lowtag)
;; ports; add #b1000 if you want to know the values for 64-bit ports.
;; And note that the numbers get a little scrambled further down.
;; --njf, 2004-08-09
- bignum ; 00001010
- ratio ; 00001110
- single-float ; 00010010
- double-float ; 00010110
- complex ; 00011010
- complex-single-float ; 00011110
- complex-double-float ; 00100010
+ bignum-widetag ; 00001010
+ ratio-widetag ; 00001110
+ single-float-widetag ; 00010010
+ double-float-widetag ; 00010110
+ complex-widetag ; 00011010
+ complex-single-float-widetag ; 00011110
+ complex-double-float-widetag ; 00100010
- code-header ; 00100110
+ code-header-widetag ; 00100110
- simple-fun-header ; 00101010
- closure-header ; 00101110
- funcallable-instance-header ; 00110010
+ simple-fun-header-widetag ; 00101010
+ closure-header-widetag ; 00101110
+ funcallable-instance-header-widetag ; 00110010
- return-pc-header ; 00110110
- value-cell-header ; 00111010
- symbol-header ; 00111110
- character ; 01000010
- sap ; 01000110
- unbound-marker ; 01001010
- weak-pointer ; 01001110
- instance-header ; 01010010
- fdefn ; 01010110
+ return-pc-header-widetag ; 00110110
+ value-cell-header-widetag ; 00111010
+ symbol-header-widetag ; 00111110
+ character-widetag ; 01000010
+ sap-widetag ; 01000110
+ unbound-marker-widetag ; 01001010
+ weak-pointer-widetag ; 01001110
+ instance-header-widetag ; 01010010
+ fdefn-widetag ; 01010110
- unused00 ; 01011010
- unused01 ; 01011110
- unused02 ; 01100010
- unused03 ; 01100110
- unused04 ; 01101010
- unused05 ; 01101110
- unused06 ; 01110010
- unused07 ; 01110110
+ no-tls-value-marker-widetag ; 01011010
+ #!-sb-simd-pack
+ unused01-widetag
+ #!+sb-simd-pack
+ simd-pack-widetag ; 01011110
+ unused02-widetag ; 01100010
+ unused03-widetag ; 01100110
+ unused04-widetag ; 01101010
+ unused05-widetag ; 01101110
+ unused06-widetag ; 01110010
+ unused07-widetag ; 01110110
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- unused08 ; 01111010
+ unused08-widetag ; 01111010
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- unused09 ; 01111110
+ unused09-widetag ; 01111110
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- unused10 ; 10000010
+ unused10-widetag ; 10000010
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- unused11 ; 10000110
+ unused11-widetag ; 10000110
- simple-array-unsigned-byte-2 ; 10001010
- simple-array-unsigned-byte-4 ; 10001110
- simple-array-unsigned-byte-7 ; 10010010
- simple-array-unsigned-byte-8 ; 10010110
- simple-array-unsigned-byte-15 ; 10011010
- simple-array-unsigned-byte-16 ; 10011110
- simple-array-nil ; 10100010
- simple-base-string ; 10100110
- #!+sb-unicode simple-character-string
- simple-bit-vector ; 10101010
- simple-vector ; 10101110
+ simple-array-unsigned-byte-2-widetag ; 10001010
+ simple-array-unsigned-byte-4-widetag ; 10001110
+ simple-array-unsigned-byte-7-widetag ; 10010010
+ simple-array-unsigned-byte-8-widetag ; 10010110
+ simple-array-unsigned-byte-15-widetag ; 10011010
+ simple-array-unsigned-byte-16-widetag ; 10011110
+ simple-array-nil-widetag ; 10100010
+ simple-base-string-widetag ; 10100110
+ #!+sb-unicode simple-character-string-widetag
+ simple-bit-vector-widetag ; 10101010
+ simple-vector-widetag ; 10101110
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- simple-array-unsigned-byte-29 ; 10110010
- simple-array-unsigned-byte-31 ; 10110110
- simple-array-unsigned-byte-32 ; 10111010
+ simple-array-unsigned-fixnum-widetag ; 10110010
+ simple-array-unsigned-byte-31-widetag ; 10110110
+ simple-array-unsigned-byte-32-widetag ; 10111010
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- simple-array-unsigned-byte-60
+ simple-array-unsigned-fixnum-widetag
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- simple-array-unsigned-byte-63
+ simple-array-unsigned-byte-63-widetag
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- simple-array-unsigned-byte-64
- simple-array-signed-byte-8 ; 10111110
- simple-array-signed-byte-16 ; 11000010
+ simple-array-unsigned-byte-64-widetag
+ simple-array-signed-byte-8-widetag ; 10111110
+ simple-array-signed-byte-16-widetag ; 11000010
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- simple-array-signed-byte-30 ; 11000110
- simple-array-signed-byte-32 ; 11001010
+ simple-array-fixnum-widetag ; 11000110
+ simple-array-signed-byte-32-widetag ; 11001010
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- simple-array-signed-byte-61
+ simple-array-fixnum-widetag
#!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
- simple-array-signed-byte-64
- simple-array-single-float ; 11001110
- simple-array-double-float ; 11010010
- simple-array-complex-single-float ; 11010110
- simple-array-complex-double-float ; 11011010
- simple-array ; 11011110
- complex-vector-nil ; 11100010
- complex-base-string ; 11100110
- #!+sb-unicode complex-character-string
- complex-bit-vector ; 11101010
- complex-vector ; 11101110
- complex-array ; 11110010
+ simple-array-signed-byte-64-widetag
+ simple-array-single-float-widetag ; 11001110
+ simple-array-double-float-widetag ; 11010010
+ simple-array-complex-single-float-widetag ; 11010110
+ simple-array-complex-double-float-widetag ; 11011010
+ simple-array-widetag ; 11011110
+ complex-vector-nil-widetag ; 11100010
+ complex-base-string-widetag ; 11100110
+ #!+sb-unicode complex-character-string-widetag
+ complex-bit-vector-widetag ; 11101010
+ complex-vector-widetag ; 11101110
+ complex-array-widetag ; 11110010
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
- unused12 ; 11110110
+ unused12-widetag ; 11110110
#!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
(not sb-unicode))
- unused13 ; 11111010
+ unused13-widetag ; 11111010
#!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
(not sb-unicode))
- unused14 ; 11111110
+ unused14-widetag ; 11111110
)
;;; the different vector subtypes
-(defenum (:prefix vector- :suffix -subtype)
- normal
- unused
- valid-hashing
- must-rehash)
+(defenum ()
+ vector-normal-subtype
+ vector-unused-subtype
+ vector-valid-hashing-subtype)
projects / sbcl.git / blobdiff