diff --git a/compiler/generic/objdef.lisp b/compiler/generic/objdef.lisp index 97f20c7cc515c7a6ea4ff08836f6e81d9bd01749..95a684dd93090cb3f09f81abd289b454945a7dfc 100644 --- a/compiler/generic/objdef.lisp +++ b/compiler/generic/objdef.lisp @@ -5,7 +5,7 @@ ;;; Carnegie Mellon University, and has been placed in the public domain. ;;; (ext:file-comment - "$Header: /Volumes/share2/src/cmucl/cvs2git/cvsroot/src/compiler/generic/objdef.lisp,v 1.46 2002/09/03 16:29:45 toy Exp $") + "$Header: /Volumes/share2/src/cmucl/cvs2git/cvsroot/src/compiler/generic/objdef.lisp,v 1.47 2002/09/04 11:21:02 toy Exp $") ;;; ;;; ********************************************************************** ;;; @@ -65,6 +65,16 @@ (eval-when (compile eval load) +(defconstant lowtag-bits 3 + "Number of bits at the low end of a pointer used for type information.") + +(defconstant lowtag-mask (1- (ash 1 lowtag-bits)) + "Mask to extract the low tag bits from a pointer.") + +(defconstant lowtag-limit (ash 1 lowtag-bits) + "Exclusive upper bound on the value of the low tag bits from a + pointer.") + (defconstant type-bits 8 "Number of bits used in the header word of a data block for typeing.")