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Sar-spec

Sar-spec-8

Signature
(sar-spec-8 dst src input-rflags) → (mv * * *)
Arguments: src — Note that src is masked appropriately by the caller of this function.

Definitions and Theorems

Function: sar-spec-8

(defun sar-spec-8 (dst src input-rflags)
 (declare (type (unsigned-byte 8) dst)
          (type (unsigned-byte 6) src)
          (type (unsigned-byte 32) input-rflags))
 (let ((__function__ 'sar-spec-8))
  (declare (ignorable __function__))
  (b*
   ((dst (mbe :logic (n-size 8 dst) :exec dst))
    (src (mbe :logic (n-size 6 src) :exec src))
    (input-rflags (mbe :logic (n32 input-rflags)
                       :exec input-rflags))
    (neg-src (the (signed-byte 9) (- src)))
    (raw-result-not-sign-extended
         (the (unsigned-byte 8)
              (ash (the (unsigned-byte 8) dst)
                   (the (signed-byte 9) neg-src))))
    (raw-result
     (if (eql (mbe :logic (logbit 7 dst)
                   :exec (the (unsigned-byte 1)
                              (ash (the (unsigned-byte 8) dst) -7)))
              1)
         (loghead 8
                  (ash (mbe :logic (logext 8 dst)
                            :exec (fast-logext 8 dst))
                       neg-src))
       raw-result-not-sign-extended))
    (result (mbe :logic (n-size 8 raw-result)
                 :exec raw-result))
    ((mv (the (unsigned-byte 32) output-rflags)
         (the (unsigned-byte 32)
              undefined-flags))
     (case src
      (0 (mv input-rflags 0))
      (1
       (b*
        ((cf
           (mbe :logic (part-select dst :low 0 :width 1)
                :exec (the (unsigned-byte 1)
                           (logand 1 (the (unsigned-byte 8) dst)))))
         (pf (general-pf-spec 8 result))
         (zf (zf-spec result))
         (sf (general-sf-spec 8 result))
         (of 0)
         (output-rflags
          (mbe
           :logic (change-rflagsbits input-rflags
                                     :cf cf
                                     :pf pf
                                     :zf zf
                                     :sf sf
                                     :of of)
           :exec
           (the
            (unsigned-byte 32)
            (!rflagsbits->cf
             cf
             (!rflagsbits->pf
                  pf
                  (!rflagsbits->zf
                       zf
                       (!rflagsbits->sf
                            sf
                            (!rflagsbits->of of input-rflags))))))))
         (undefined-flags (the (unsigned-byte 32)
                               (!rflagsbits->af 1 0))))
        (mv output-rflags undefined-flags)))
      (otherwise
       (b*
        ((cf
          (if (<= 8 src)
              (mbe :logic (part-select dst :low 7 :width 1)
                   :exec
                   (let* ((shft (the (signed-byte 8) -7)))
                     (the (unsigned-byte 1)
                          (ash (the (unsigned-byte 8) dst)
                               (the (signed-byte 8) shft)))))
           (mbe
            :logic
            (part-select dst :low (1- src) :width 1)
            :exec
            (let* ((shft (the (signed-byte 8)
                              (- 1 (the (unsigned-byte 8) src)))))
             (the
                (unsigned-byte 1)
                (logand 1
                        (the (unsigned-byte 8)
                             (ash (the (unsigned-byte 8) dst)
                                  (the (signed-byte 8) shft)))))))))
         (pf (general-pf-spec 8 result))
         (zf (zf-spec result))
         (sf (general-sf-spec 8 result))
         (output-rflags
          (mbe
           :logic (change-rflagsbits input-rflags
                                     :cf cf
                                     :pf pf
                                     :zf zf
                                     :sf sf)
           :exec
           (the
              (unsigned-byte 32)
              (!rflagsbits->cf
                   cf
                   (!rflagsbits->pf
                        pf
                        (!rflagsbits->zf
                             zf
                             (!rflagsbits->sf sf input-rflags)))))))
         (undefined-flags
          (mbe
            :logic (change-rflagsbits 0 :af 1 :of 1)
            :exec (the (unsigned-byte 32)
                       (!rflagsbits->af 1 (!rflagsbits->of 1 0))))))
        (mv output-rflags undefined-flags)))))
    (output-rflags (mbe :logic (n32 output-rflags)
                        :exec output-rflags))
    (undefined-flags (mbe :logic (n32 undefined-flags)
                          :exec undefined-flags)))
   (mv result output-rflags undefined-flags))))

Theorem: n08-mv-nth-0-sar-spec-8

(defthm n08-mv-nth-0-sar-spec-8
 (unsigned-byte-p 8
                  (mv-nth 0 (sar-spec-8 dst src input-rflags)))
 :rule-classes
 (:rewrite
  (:type-prescription
      :corollary (natp (mv-nth 0 (sar-spec-8 dst src input-rflags)))
      :hints
      (("Goal" :in-theory '(unsigned-byte-p integer-range-p natp))))
  (:linear
   :corollary (and (<= 0
                       (mv-nth 0 (sar-spec-8 dst src input-rflags)))
                   (< (mv-nth 0 (sar-spec-8 dst src input-rflags))
                      256))
   :hints
   (("Goal"
        :in-theory '(unsigned-byte-p integer-range-p (:e expt)))))))

Theorem: mv-nth-1-sar-spec-8

(defthm mv-nth-1-sar-spec-8
 (unsigned-byte-p 32
                  (mv-nth 1 (sar-spec-8 dst src input-rflags)))
 :rule-classes
 (:rewrite
  (:type-prescription
      :corollary (natp (mv-nth 1 (sar-spec-8 dst src input-rflags)))
      :hints
      (("Goal" :in-theory '(unsigned-byte-p integer-range-p natp))))
  (:linear
   :corollary (and (<= 0
                       (mv-nth 1 (sar-spec-8 dst src input-rflags)))
                   (< (mv-nth 1 (sar-spec-8 dst src input-rflags))
                      4294967296))
   :hints
   (("Goal"
        :in-theory '(unsigned-byte-p integer-range-p (:e expt)))))))

Theorem: mv-nth-2-sar-spec-8

(defthm mv-nth-2-sar-spec-8
 (unsigned-byte-p 32
                  (mv-nth 2 (sar-spec-8 dst src input-rflags)))
 :rule-classes
 (:rewrite
  (:type-prescription
      :corollary (natp (mv-nth 2 (sar-spec-8 dst src input-rflags)))
      :hints
      (("Goal" :in-theory '(unsigned-byte-p integer-range-p natp))))
  (:linear
   :corollary (and (<= 0
                       (mv-nth 2 (sar-spec-8 dst src input-rflags)))
                   (< (mv-nth 2 (sar-spec-8 dst src input-rflags))
                      4294967296))
   :hints
   (("Goal"
        :in-theory '(unsigned-byte-p integer-range-p (:e expt)))))))