(in-package "SB!VM")
-;;; FIXME: It's clever using :SUFFIX -TYPE 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.
+;;; 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 three
-;;; bits to identify the type of a machine word. Certain constraints
+;;; 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:
;;; * 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 + 4 = OTHER-POINTER-LOWTAG: NIL is both a
-;;; cons and a symbol (at the same address) and depends on this.
+;;; * 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,
;;; which uses bit 2 of the ALLOC register to indicate that
;;; 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
+;;; 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
;; 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)
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
(defenum (:suffix -lowtag)
even-fixnum
- ;; Note: CMU CL, and SBCL < 0.pre7.39, had FUN-POINTER-LOWTAG
- ;; here. We swapped FUN-POINTER-LOWTAG and
- ;; INSTANCE-POINTER-LOWTAG in sbcl-0.pre7.39 in order to help with a
- ;; low-level pun in the function call sequence on the PPC port.
- ;; For more information, see the PPC port code. -- WHN 2001-10-03
instance-pointer
other-immediate-0
list-pointer
other-immediate-1
other-pointer))
+(def!constant nil-value
+ (+ static-space-start n-word-bytes other-pointer-lowtag))
+
;;; 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)
;;; ANDcc tag, 0xA6, tag
;;; JNE tag, label
;;;
-;;; rather than two separate tests and jumps
+;;; rather than two separate tests and jumps
(defenum (:suffix -widetag
- :start (+ (ash 1 n-lowtag-bits) other-immediate-0-lowtag)
- :step (ash 1 (1- n-lowtag-bits)))
- bignum
- ratio
- single-float
- double-float
- #!+long-float long-float
- complex
- complex-single-float
- complex-double-float
- #!+long-float complex-long-float
+ ;; 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)
+ ;; NOTE: the binary numbers off to the side are only valid for 32-bit
+ ;; 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
+
+ code-header ; 00100110
+
+ simple-fun-header ; 00101010
+ closure-header ; 00101110
+ funcallable-instance-header ; 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
- code-header
- simple-fun-header
- closure-header
- funcallable-instance-header
+ unused00 ; 01011010
+ unused01 ; 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
- return-pc-header
- value-cell-header
- symbol-header
- base-char
- sap
- unbound-marker
- weak-pointer
- instance-header
- fdefn
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ unused10 ; 10000010
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ unused11 ; 10000110
- unused00
- unused01
- unused02
- unused03
- unused04
- unused05
- unused06
- unused07
- #!-long-float unused08
- #!-long-float unused09
-
- #!+long-float simple-array-long-float
- #!+long-float simple-array-complex-long-float
- #!-long-float unused10
- #!-long-float unused11
+ 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
+ #!+#.(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
+ #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
+ simple-array-unsigned-byte-60
+ #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
+ simple-array-unsigned-byte-63
+ #!+#.(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
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ simple-array-signed-byte-30 ; 11000110
+ simple-array-signed-byte-32 ; 11001010
+ #!+#.(cl:if (cl:= 64 sb!vm:n-word-bits) '(and) '(or))
+ simple-array-signed-byte-61
+ #!+#.(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-unsigned-byte-2
- simple-array-unsigned-byte-4
- simple-array-unsigned-byte-7
- simple-array-unsigned-byte-8
- simple-array-unsigned-byte-15
- simple-array-unsigned-byte-16
- simple-array-nil
- simple-base-string
- simple-bit-vector
- simple-vector
- simple-array-unsigned-byte-29
- simple-array-unsigned-byte-31
- simple-array-unsigned-byte-32
- simple-array-signed-byte-8
- simple-array-signed-byte-16
- simple-array-signed-byte-30
- simple-array-signed-byte-32
- simple-array-single-float
- simple-array-double-float
- simple-array-complex-single-float
- simple-array-complex-double-float
- simple-array
- complex-vector-nil
- complex-base-string
- complex-bit-vector
- complex-vector
- complex-array
+ #!+#.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ unused12 ; 11110110
+ #!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ (not sb-unicode))
+ unused13 ; 11111010
+ #!+(and #.(cl:if (cl:= 32 sb!vm:n-word-bits) '(and) '(or))
+ (not sb-unicode))
+ unused14 ; 11111110
)
;;; the different vector subtypes
projects / sbcl.git / blobdiff