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Sar-spec

Sar-spec-32

Signature
(sar-spec-32 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-32

(defun sar-spec-32 (dst src input-rflags)
 (declare (type (unsigned-byte 32) dst)
          (type (unsigned-byte 6) src)
          (type (unsigned-byte 32) input-rflags))
 (let ((__function__ 'sar-spec-32))
  (declare (ignorable __function__))
  (b*
   ((dst (mbe :logic (n-size 32 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 33) (- src)))
    (raw-result-not-sign-extended
         (the (unsigned-byte 32)
              (ash (the (unsigned-byte 32) dst)
                   (the (signed-byte 33) neg-src))))
    (raw-result
      (if
       (eql (mbe :logic (logbit 31 dst)
                 :exec (the (unsigned-byte 1)
                            (ash (the (unsigned-byte 32) dst) -31)))
            1)
       (loghead 32
                (ash (mbe :logic (logext 32 dst)
                          :exec (fast-logext 32 dst))
                     neg-src))
       raw-result-not-sign-extended))
    (result (mbe :logic (n-size 32 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 32) dst)))))
         (pf (general-pf-spec 32 result))
         (zf (zf-spec result))
         (sf (general-sf-spec 32 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 (<= 32 src)
              (mbe :logic
                   (part-select dst :low 31 :width 1)
                   :exec
                   (let* ((shft (the (signed-byte 32) -31)))
                     (the (unsigned-byte 1)
                          (ash (the (unsigned-byte 32) dst)
                               (the (signed-byte 32) shft)))))
           (mbe
            :logic
            (part-select dst :low (1- src) :width 1)
            :exec
            (let* ((shft (the (signed-byte 32)
                              (- 1 (the (unsigned-byte 32) src)))))
             (the
               (unsigned-byte 1)
               (logand 1
                       (the (unsigned-byte 32)
                            (ash (the (unsigned-byte 32) dst)
                                 (the (signed-byte 32) shft)))))))))
         (pf (general-pf-spec 32 result))
         (zf (zf-spec result))
         (sf (general-sf-spec 32 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: n32-mv-nth-0-sar-spec-32

(defthm n32-mv-nth-0-sar-spec-32
 (unsigned-byte-p 32
                  (mv-nth 0 (sar-spec-32 dst src input-rflags)))
 :rule-classes
 (:rewrite
  (:type-prescription
     :corollary (natp (mv-nth 0 (sar-spec-32 dst src input-rflags)))
     :hints
     (("Goal" :in-theory '(unsigned-byte-p integer-range-p natp))))
  (:linear
   :corollary
   (and (<= 0
            (mv-nth 0 (sar-spec-32 dst src input-rflags)))
        (< (mv-nth 0 (sar-spec-32 dst src input-rflags))
           4294967296))
   :hints
   (("Goal"
        :in-theory '(unsigned-byte-p integer-range-p (:e expt)))))))

Theorem: mv-nth-1-sar-spec-32

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

Theorem: mv-nth-2-sar-spec-32

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