Autogenerate a constant

src/compiler/generic/objdef.lisp

@@ -377,7 +377,7 @@
 ;;; in c-land. However, we need sight of so many parts of it from Lisp that
 ;;; it makes sense to define it here anyway, so that the GENESIS machinery
 ;;; can take care of maintaining Lisp and C versions.
-(!define-primitive-object (thread)
+(!define-primitive-object (thread :size primitive-thread-object-length)
  ;; no_tls_value_marker is borrowed very briefly at thread startup to
  ;; pass the address of initial-function into new_thread_trampoline.
  ;; tls[0] = NO_TLS_VALUE_MARKER_WIDETAG because a the tls index slot
@@ -477,11 +477,6 @@
  ;; but we need somewhere to read it from.
  #!+(and immobile-space 64-bit sb-thread) (function-layout))
 
-(defconstant primitive-thread-object-length
- (sb!vm::primitive-object-length
- (find 'sb!vm::thread sb!vm::*primitive-objects*
- :key 'sb!vm::primitive-object-name)))
-
 ;;; Compute the smallest TLS index that will be assigned to a special variable
 ;;; that does not map onto a thread slot.
 ;;; Given N thread slots, the tls indices are 0..N-1 scaled by word-shift.

src/compiler/generic/vm-macs.lisp

@@ -70,7 +70,8 @@
 (defvar *!late-primitive-object-forms* nil)
 
 (defmacro !define-primitive-object
- ((name &key lowtag widetag alloc-trans (type t))
+ ((name &key lowtag widetag alloc-trans (type t)
+ (size (symbolicate name "-SIZE")))
  &rest slot-specs)
  (collect ((slots) (specials) (constants) (forms) (inits))
  (let ((offset (if widetag 1 0))
@@ -141,7 +142,7 @@
  (setf variable-length-p t))
  (incf offset length)))
  (unless variable-length-p
- (constants `(defconstant ,(symbolicate name "-SIZE") ,offset)))
+ (constants `(defconstant ,size ,offset)))
  #-c-headers-only
  (when alloc-trans
  (forms `(def-alloc ,alloc-trans ,offset