		Search-engine friendly clone of the ACL2 documentation.

State-stobj

Read1-xreg-signed

Refine read-xreg-signed to use the stobj states.

Definitions and Theorems

Function: read1-xreg-signed

(defun read1-xreg-signed (reg stat feat)
 (declare (xargs :non-executable t))
 (declare
  (xargs :guard (non-exec (and (stat1p stat)
                               (natp reg)
                               (statp (stat-from-stat1 stat))
                               (featp feat)
                               (stat-validp (stat-from-stat1 stat)
                                            feat)
                               (< (lnfix reg) (feat->xnum feat))))))
 (prog2$ (acl2::throw-nonexec-error 'read1-xreg-signed
                                    (list reg stat feat))
         (if (acl2::mbt$ (stat1p stat))
             (logext (feat->xlen feat)
                     (read-xreg-unsigned reg (stat-from-stat1 stat)
                                         feat))
           0)))

Theorem: read1-xreg-signed-to-read-xreg-signed

(defthm read1-xreg-signed-to-read-xreg-signed
  (implies (stat1p stat)
           (equal (read1-xreg-signed reg stat feat)
                  (read-xreg-signed reg (stat-from-stat1 stat)
                                    feat)))
  :rule-classes :rewrite)

Theorem: read-xreg-signed-to-read1-xreg-signed

(defthm read-xreg-signed-to-read1-xreg-signed
  (implies (statp stat)
           (equal (read-xreg-signed reg stat feat)
                  (read1-xreg-signed reg (stat1-from-stat stat)
                                     feat)))
  :rule-classes :rewrite)