;;; '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
+;;; bits to identify the type of a machine word. Certain constraints
;;; apply:
;;; * EVEN-FIXNUM-LOWTAG and ODD-FIXNUM-LOWTAG must be 0 and 4: code
;;; which shifts left two places to convert raw integers to tagged
;;; fixnums is ubiquitous.
-;;; * LIST-POINTER-LOWTAG + N-WORD-BYTES = OTHER-POINTER-LOWTAG: NIL
+;;; * LIST-POINTER-LOWTAG + N-WORD-BYTES = OTHER-POINTER-LOWTAG: NIL
;;; is both a cons and a symbol (at the same address) and depends on this.
;;; See the definition of SYMBOL in objdef.lisp
;;; * OTHER-POINTER-LOWTAG > 4: Some code in the SPARC backend,
;;; PSEUDO-ATOMIC is on, doesn't strip the low bits of reg_ALLOC
;;; before ORing in OTHER-POINTER-LOWTAG within a PSEUDO-ATOMIC
;;; section.
-;;; * OTHER-IMMEDIATE-0-LOWTAG are spaced 4 apart: various code wants to
+;;; * OTHER-IMMEDIATE-0-LOWTAG are spaced 4 apart: various code wants to
;;; iterate through these
+;;; * Allocation code on Alpha wants lowtags for heap-allocated
+;;; objects to be odd.
;;; (These are just the ones we know about as of sbcl-0.7.1.22. There
;;; might easily be more, since these values have stayed highly
;;; constrained for more than a decade, an inviting target for
;;; ANDcc tag, 0xA6, tag
;;; JNE tag, label
;;;
-;;; rather than two separate tests and jumps
+;;; rather than two separate tests and jumps
(defenum (:suffix -widetag
;; 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)
- :step 4)
+ :start (+ (ash 1 n-lowtag-bits) other-immediate-0-lowtag)
+ :step 4)
;; NOTE: the binary numbers off to the side are only valid for 32-bit
- ;; ports; add #x1000 if you want to know the values for 64-bit ports.
+ ;; 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
instance-header ; 01010010
fdefn ; 01010110
- unused00 ; 01011010
- unused01 ; 01011110
+ no-tls-value-marker ; 01011010
+ #!-(and sb-lutex sb-thread)
+ unused01
+ #!+(and sb-lutex sb-thread)
+ lutex ; 01011110
unused02 ; 01100010
unused03 ; 01100110
unused04 ; 01101010
unused05 ; 01101110
unused06 ; 01110010
unused07 ; 01110110
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
unused08 ; 01111010
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
unused09 ; 01111110
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
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
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
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
#!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
unused12 ; 11110110
- #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ #!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ (not sb-unicode))
unused13 ; 11111010
- #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ #!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ (not sb-unicode))
unused14 ; 11111110
)
(defenum (:prefix vector- :suffix -subtype)
normal
unused
- valid-hashing
- must-rehash)
+ valid-hashing)