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Computation-states

Read-object-of-create-var

How read-object changes under create-var.

The theorem that equates read-object after create-var to a conditional term is limited to top-level object designators. Handling other kinds of object designators is more complicated, due to the possibility of partial overlap of objects; we plan to tackle these eventually.

The theorem that assumes the existence of the object before the variable creation works with every kind of object designator.

Definitions and Theorems

Theorem: read-object-of-create-var-when-static

(defthm read-object-of-create-var-when-static
  (implies (and (equal (objdesign-kind objdes) :static)
                (not (errorp (create-var var val compst)))
                (identp var))
           (equal (read-object objdes (create-var var val compst))
                  (if (and (equal (compustate-frames-number compst)
                                  0)
                           (equal (objdesign-static->name objdes)
                                  var))
                      (remove-flexible-array-member val)
                    (read-object objdes compst)))))

Theorem: read-object-of-create-var-when-alloc

(defthm read-object-of-create-var-when-alloc
  (implies (and (equal (objdesign-kind objdes) :alloc)
                (not (errorp (create-var var val compst)))
                (identp var))
           (equal (read-object objdes (create-var var val compst))
                  (read-object objdes compst))))

Theorem: read-object-of-create-var-when-auto

(defthm read-object-of-create-var-when-auto
 (implies
  (and (equal (objdesign-kind objdes) :auto)
       (not (errorp (create-var var val compst)))
       (identp var))
  (equal
     (read-object objdes (create-var var val compst))
     (if (and (> (compustate-frames-number compst) 0)
              (equal (objdesign-auto->name objdes)
                     var)
              (equal (objdesign-auto->frame objdes)
                     (1- (compustate-frames-number compst)))
              (equal (objdesign-auto->scope objdes)
                     (1- (len (frame->scopes (top-frame compst))))))
         (remove-flexible-array-member val)
       (read-object objdes compst)))))

Theorem: read-object-of-create-var-when-auto/static/alloc

(defthm read-object-of-create-var-when-auto/static/alloc
 (implies
  (and (member-equal (objdesign-kind objdes)
                     '(:auto :static :alloc))
       (not (errorp (create-var var val compst)))
       (identp var))
  (equal
   (read-object objdes (create-var var val compst))
   (if
    (or (and (equal (objdesign-kind objdes) :static)
             (equal (compustate-frames-number compst)
                    0)
             (equal (objdesign-static->name objdes)
                    var))
        (and (equal (objdesign-kind objdes) :auto)
             (> (compustate-frames-number compst) 0)
             (equal (objdesign-auto->name objdes)
                    var)
             (equal (objdesign-auto->frame objdes)
                    (1- (compustate-frames-number compst)))
             (equal (objdesign-auto->scope objdes)
                    (1- (len (frame->scopes (top-frame compst)))))))
    (remove-flexible-array-member val)
    (read-object objdes compst)))))

Theorem: read-object-of-create-var-when-existing

(defthm read-object-of-create-var-when-existing
  (b* ((compst1 (create-var var val compst)))
    (implies (and (not (errorp compst1))
                  (not (errorp (read-object objdes compst))))
             (equal (read-object objdes compst1)
                    (read-object objdes compst)))))