Commit 395c461b authored by Juho Snellman's avatar Juho Snellman
Browse files

1.0.24.48: Do explicit sign-extension of small signed alien return values 

        * gcc 4.3 has a different interpretation of the ABI, and
          zero-extends signed chars, shorts and (on x86-64) ints.
parent 2ff7f7e7

NEWS

+2 −0
Original line number Diff line number Diff line
@@ -30,6 +30,8 @@ changes in sbcl-1.0.25 relative to 1.0.24: 
    unquoted symbol. Regression from 1.0.22.8. (reported by Ariel Badichi)

  * bug fix: named ENUMs in multiply-referenced alien record types no longer

    cause an implied type redefinition.  Regression from 1.0.21.29.

  * bug fix: sign-extension of small signed return values now works with C

    code compiled with gcc 4.3 or newer. (reported by Liam Healy)

  * improvements to the Windows port:

    ** SB-BSD-SOCKETS now works from saved cores as well. (reported by Stephen

       Westfold, thanks to Rudi Schlatte)

src/compiler/x86-64/c-call.lisp

+21 −16
Original line number Diff line number Diff line
@@ -74,8 +74,6 @@ 
    (0 eax-offset)

    (1 edx-offset)))



;; XXX The return handling probably doesn't conform to the ABI



(define-alien-type-method (integer :result-tn) (type state)

  (let ((num-results (result-state-num-results state)))

    (setf (result-state-num-results state) (1+ num-results))
@@ -88,7 +86,7 @@ 
(define-alien-type-method (integer :naturalize-gen) (type alien)

  (if (and (alien-integer-type-signed type)

           (<= (alien-type-bits type) 32))

      `(sign-extend ,alien)

      `(sign-extend ,alien ,(alien-type-bits type))

      alien))



(define-alien-type-method (system-area-pointer :result-tn) (type state)
@@ -191,34 +189,41 @@ 
                                    ,@(new-args))))))

        (sb!c::give-up-ir1-transform))))



;;; The ABI specifies that signed short/int's are returned as 32-bit

;;; values. Negative values need to be sign-extended to 64-bits (done

;;; in a :NATURALIZE-GEN alien-type-method).

(defknown sign-extend ((signed-byte 32)) fixnum

;;; The ABI is vague about how signed sub-word integer return values

;;; are handled, but since gcc versions >=4.3 no longer do sign

;;; extension in the callee, we need to do it in the caller.

(defknown sign-extend ((signed-byte 32) t) fixnum

    (foldable flushable movable))



(define-vop (sign-extend)

  (:translate sign-extend)

  (:policy :fast-safe)

  (:args (val :scs (signed-reg)))

  (:arg-types fixnum)

  (:arg-types fixnum (:constant fixnum))

  (:info size)

  (:results (res :scs (signed-reg)))

  (:result-types fixnum)

  (:generator 1

   (inst movsxd res

         (make-random-tn :kind :normal

                         :sc (sc-or-lose 'dword-reg)

                         :sc (sc-or-lose (ecase size

                                           (8 'byte-reg)

                                           (16 'word-reg)

                                           (32 'dword-reg)))

                         :offset (tn-offset val)))))



#-sb-xc-host

(defun sign-extend (x)

  (declare (type (signed-byte 32) x))

  (sign-extend x))

(defun sign-extend (x size)

  (declare (type fixnum x))

  (ecase size

    (8 (sign-extend x size))

    (16 (sign-extend x size))

    (32 (sign-extend x size))))



#+sb-xc-host

(defun sign-extend (x)

  (if (logbitp 31 x)

      (dpb x (byte 32 0) -1)

(defun sign-extend (x size)

  (if (logbitp (1- size) x)

      (dpb x (byte size 0) -1)

      x))



(define-vop (foreign-symbol-sap)

src/compiler/x86/c-call.lisp

+45 −0
Original line number Diff line number Diff line
@@ -78,6 +78,12 @@ 
            (values 'unsigned-byte-32 'unsigned-reg))

      (my-make-wired-tn ptype reg-sc (result-reg-offset num-results)))))



(define-alien-type-method (integer :naturalize-gen) (type alien)

  (if (and (alien-integer-type-signed type)

           (<= (alien-type-bits type) 16))

      `(sign-extend ,alien ,(alien-type-bits type))

      alien))



(define-alien-type-method (system-area-pointer :result-tn) (type state)

  (declare (ignore type))

  (let ((num-results (result-state-num-results state)))
@@ -181,6 +187,45 @@ 
                                    ,@(new-args))))))

        (sb!c::give-up-ir1-transform))))



;;; The ABI is vague about how signed sub-word integer return values

;;; are handled, but since gcc versions >=4.3 no longer do sign

;;; extension in the callee, we need to do it in the caller.

(defknown sign-extend ((signed-byte 16) t) fixnum

    (foldable flushable movable))



(define-vop (sign-extend)

  (:translate sign-extend)

  (:policy :fast-safe)

  ;; Need to wire this to EAX since in x86 some dword registers don't

  ;; have a matching word or byte register.

  (:args (val :scs (signed-reg) :target eax))

  (:temporary (:sc signed-reg :offset eax-offset :from :eval :to :result) eax)

  (:arg-types fixnum (:constant fixnum))

  (:info size)

  (:results (res :scs (signed-reg)))

  (:result-types fixnum)

  (:ignore eax)

  (:generator 1

   (inst movsx res

         (make-random-tn :kind :normal

                         :sc (sc-or-lose (ecase size

                                           (8 'byte-reg)

                                           (16 'word-reg)))

                         :offset (tn-offset val)))))



#-sb-xc-host

(defun sign-extend (x size)

  (declare (type fixnum x))

  (ecase size

    (8 (sign-extend x size))

    (16 (sign-extend x size))))



#+sb-xc-host

(defun sign-extend (x size)

  (if (logbitp (1- size) x)

      (dpb x (byte size 0) -1)

      x))



(define-vop (foreign-symbol-sap)

  (:translate foreign-symbol-sap)

  (:policy :fast-safe)

version.lisp-expr

+1 −1
Original line number Diff line number Diff line
@@ -17,4 +17,4 @@ 
;;; checkins which aren't released. (And occasionally for internal

;;; versions, especially for internal versions off the main CVS

;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)

"1.0.24.47"
 
"1.0.24.48"