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- #| -*-Scheme-*-
-
- $Id: assmd.scm,v 1.2 1999/01/02 06:06:43 cph Exp $
- $MC68020-Header: assmd.scm,v 1.36 89/08/28 18:33:33 GMT cph Exp $
-
- Copyright (c) 1988, 1989, 1990, 1999 Massachusetts Institute of Technology
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or (at
- your option) any later version.
-
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- |#
-
- ;;;; Assembler Machine Dependencies
-
- (declare (usual-integrations))
-
- (let-syntax ((ucode-type (macro (name) `',(microcode-type name))))
-
- (define-integrable maximum-padding-length
- ;; Instruction length is always a multiple of 32 bits
- ;; Would 0 work here?
- 32)
-
- (define padding-string
- ;; Pad with `UNIMP' instructions
- (unsigned-integer->bit-string maximum-padding-length
- #b00000000000000000000000000000000 ))
-
- (define-integrable block-offset-width
- ;; Block offsets are always 16 bit words
- 16)
-
- (define-integrable maximum-block-offset
- ;; PC always aligned on longword boundary. Use the extra bit.
- (- (expt 2 (1+ block-offset-width)) 4))
-
- (define (block-offset->bit-string offset start?)
- (unsigned-integer->bit-string block-offset-width
- (+ (quotient offset 2)
- (if start? 0 1))))
-
- (define (make-nmv-header n)
- (bit-string-append (unsigned-integer->bit-string scheme-datum-width n)
- nmv-type-string))
-
- (define nmv-type-string
- (unsigned-integer->bit-string scheme-type-width
- (ucode-type manifest-nm-vector)))
-
- (define (object->bit-string object)
- (bit-string-append
- (unsigned-integer->bit-string scheme-datum-width
- (careful-object-datum object))
- (unsigned-integer->bit-string scheme-type-width (object-type object))))
-
- ;;; Machine dependent instruction order
-
- (define (instruction-insert! bits block position receiver)
- (let ((l (bit-string-length bits)))
- (if (eq? endianness 'LITTLE)
- (begin
- (bit-substring-move-right! bits 0 l block position)
- (receiver (+ position l)))
- (let ((new-position (- position l)))
- (bit-substring-move-right! bits 0 l block new-position)
- (receiver new-position)))))
-
- (define-integrable instruction-initial-position bit-string-length)
- (define-integrable instruction-append bit-string-append-reversed)
-
- ;;; end let-syntax
- )