#| -*-Scheme-*-

$Id: rgraph.scm,v 4.13 2007/01/05 21:19:23 cph Exp $

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    1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    2006, 2007 Massachusetts Institute of Technology

This file is part of MIT/GNU Scheme.

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it under the terms of the GNU General Public License as published by
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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.

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|#

;;;; Program Graph Abstraction

(declare (usual-integrations))

(define-structure (rgraph (type vector)
			  (copier #f)
			  (constructor make-rgraph (n-registers)))
  n-registers
  (entry-edges '())
  (bblocks '())
  register-bblock
  register-n-refs
  register-n-deaths
  register-live-length
  register-crosses-call?
  register-value-classes
  register-known-values)

(define (add-rgraph-bblock! rgraph bblock)
  (set-rgraph-bblocks! rgraph (cons bblock (rgraph-bblocks rgraph))))

(define (delete-rgraph-bblock! rgraph bblock)
  (set-rgraph-bblocks! rgraph (delq! bblock (rgraph-bblocks rgraph))))

(define (add-rgraph-entry-edge! rgraph edge)
  (set-rgraph-entry-edges! rgraph (cons edge (rgraph-entry-edges rgraph))))

(define-integrable rgraph-register-renumber rgraph-register-bblock)
(define-integrable set-rgraph-register-renumber! set-rgraph-register-bblock!)

(define *rgraphs*)
(define *current-rgraph*)

(define (rgraph-initial-edges rgraph)
  (list-transform-positive (rgraph-entry-edges rgraph)
    (lambda (edge)
      (node-previous=0? (edge-right-node edge)))))