src/compiler/x86/alloc.lisp

   1 ;;;; allocation VOPs for the x86
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; This software is derived from the CMU CL system, which was
   7 ;;;; written at Carnegie Mellon University and released into the
   8 ;;;; public domain. The software is in the public domain and is
   9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  10 ;;;; files for more information.
  11
  12 (in-package "SB!VM")
  13 \f
  14 ;;;; CONS, LIST and LIST*
  15 (define-vop (list-or-list*)
  16   (:args (things :more t))
  17   (:temporary (:sc unsigned-reg) ptr temp)
  18   (:temporary (:sc unsigned-reg :to (:result 0) :target result) res)
  19   (:info num)
  20   (:results (result :scs (descriptor-reg)))
  21   (:variant-vars star)
  22   (:policy :safe)
  23   (:node-var node)
  24   (:generator 0
  25     (cond ((zerop num)
  26            ;; (move result nil-value)
  27            (inst mov result nil-value))
  28           ((and star (= num 1))
  29            (move result (tn-ref-tn things)))
  30           (t
  31            (macrolet
  32                ((store-car (tn list &optional (slot cons-car-slot))
  33                   `(let ((reg
  34                           (sc-case ,tn
  35                             ((any-reg descriptor-reg) ,tn)
  36                             ((control-stack)
  37                              (move temp ,tn)
  38                              temp))))
  39                      (storew reg ,list ,slot list-pointer-lowtag))))
  40              (let ((cons-cells (if star (1- num) num))
  41                    (stack-allocate-p (node-stack-allocate-p node)))
  42                (maybe-pseudo-atomic stack-allocate-p
  43                 (allocation res (* (pad-data-block cons-size) cons-cells) node
  44                             stack-allocate-p list-pointer-lowtag)
  45                 (move ptr res)
  46                 (dotimes (i (1- cons-cells))
  47                   (store-car (tn-ref-tn things) ptr)
  48                   (setf things (tn-ref-across things))
  49                   (inst add ptr (pad-data-block cons-size))
  50                   (storew ptr ptr (- cons-cdr-slot cons-size)
  51                           list-pointer-lowtag))
  52                 (store-car (tn-ref-tn things) ptr)
  53                 (cond (star
  54                        (setf things (tn-ref-across things))
  55                        (store-car (tn-ref-tn things) ptr cons-cdr-slot))
  56                       (t
  57                        (storew nil-value ptr cons-cdr-slot
  58                                list-pointer-lowtag)))
  59                 (aver (null (tn-ref-across things)))))
  60              (move result res))))))
  61
  62 (define-vop (list list-or-list*)
  63   (:variant nil))
  64
  65 (define-vop (list* list-or-list*)
  66   (:variant t))
  67 \f
  68 ;;;; special-purpose inline allocators
  69
  70 ;;; ALLOCATE-VECTOR
  71 (define-vop (allocate-vector-on-heap)
  72   (:args (type :scs (unsigned-reg immediate))
  73          (length :scs (any-reg immediate))
  74          (words :scs (any-reg immediate)))
  75   (:results (result :scs (descriptor-reg) :from :load))
  76   (:arg-types positive-fixnum
  77               positive-fixnum
  78               positive-fixnum)
  79   (:policy :fast-safe)
  80   (:generator 100
  81     (let ((size (sc-case words
  82                   (immediate
  83                    (logandc2 (+ (fixnumize (tn-value words))
  84                                 (+ (1- (ash 1 n-lowtag-bits))
  85                                    (* vector-data-offset n-word-bytes)))
  86                              lowtag-mask))
  87                   (t
  88                    (inst lea result (make-ea :byte :base words :disp
  89                                              (+ (1- (ash 1 n-lowtag-bits))
  90                                                 (* vector-data-offset
  91                                                    n-word-bytes))))
  92                    (inst and result (lognot lowtag-mask))
  93                    result))))
  94       (pseudo-atomic
  95        (allocation result size)
  96        (inst lea result (make-ea :byte :base result :disp other-pointer-lowtag))
  97        (sc-case type
  98          (immediate
  99           (aver (typep (tn-value type) '(unsigned-byte 8)))
 100           (storeb (tn-value type) result 0 other-pointer-lowtag))
 101          (t
 102           (storew type result 0 other-pointer-lowtag)))
 103        (sc-case length
 104          (immediate
 105           (let ((fixnum-length (fixnumize (tn-value length))))
 106             (typecase fixnum-length
 107               ((unsigned-byte 8)
 108                (storeb fixnum-length result
 109                        vector-length-slot other-pointer-lowtag))
 110               (t
 111                (storew fixnum-length result
 112                        vector-length-slot other-pointer-lowtag)))))
 113          (t
 114           (storew length result vector-length-slot other-pointer-lowtag)))))))
 115
 116 (define-vop (allocate-vector-on-stack)
 117   (:args (type :scs (unsigned-reg immediate) :to :save)
 118          (length :scs (any-reg) :to :eval :target zero)
 119          (words :scs (any-reg) :target ecx))
 120   (:temporary (:sc any-reg :offset ecx-offset :from (:argument 2)) ecx)
 121   (:temporary (:sc any-reg :offset eax-offset :from :eval) zero)
 122   (:temporary (:sc any-reg :offset edi-offset) res)
 123   (:results (result :scs (descriptor-reg) :from :load))
 124   (:arg-types positive-fixnum
 125               positive-fixnum
 126               positive-fixnum)
 127   (:translate allocate-vector)
 128   (:policy :fast-safe)
 129   (:node-var node)
 130   (:generator 100
 131     (inst lea result (make-ea :byte :base words :disp
 132                               (+ (1- (ash 1 n-lowtag-bits))
 133                                  (* vector-data-offset n-word-bytes))))
 134     (inst and result (lognot lowtag-mask))
 135     ;; FIXME: It would be good to check for stack overflow here.
 136     (move ecx words)
 137     (inst shr ecx n-fixnum-tag-bits)
 138     (allocation result result node t other-pointer-lowtag)
 139     (inst cld)
 140     (inst lea res
 141           (make-ea :byte :base result :disp (- (* vector-data-offset n-word-bytes)
 142                                                other-pointer-lowtag)))
 143     (sc-case type
 144       (immediate
 145        (aver (typep (tn-value type) '(unsigned-byte 8)))
 146        (storeb (tn-value type) result 0 other-pointer-lowtag))
 147       (t
 148        (storew type result 0 other-pointer-lowtag)))
 149     (storew length result vector-length-slot other-pointer-lowtag)
 150     (inst xor zero zero)
 151     (inst rep)
 152     (inst stos zero)))
 153
 154 \f
 155 (define-vop (make-fdefn)
 156   (:policy :fast-safe)
 157   (:translate make-fdefn)
 158   (:args (name :scs (descriptor-reg) :to :eval))
 159   (:results (result :scs (descriptor-reg) :from :argument))
 160   (:node-var node)
 161   (:generator 37
 162     (with-fixed-allocation (result fdefn-widetag fdefn-size node)
 163       (storew name result fdefn-name-slot other-pointer-lowtag)
 164       (storew nil-value result fdefn-fun-slot other-pointer-lowtag)
 165       (storew (make-fixup 'undefined-tramp :assembly-routine)
 166               result fdefn-raw-addr-slot other-pointer-lowtag))))
 167
 168 (define-vop (make-closure)
 169   (:args (function :to :save :scs (descriptor-reg)))
 170   (:info length stack-allocate-p)
 171   (:temporary (:sc any-reg) temp)
 172   (:results (result :scs (descriptor-reg)))
 173   (:node-var node)
 174   (:generator 10
 175    (maybe-pseudo-atomic stack-allocate-p
 176      (let ((size (+ length closure-info-offset)))
 177        (allocation result (pad-data-block size) node
 178                    stack-allocate-p
 179                    fun-pointer-lowtag)
 180        (storew (logior (ash (1- size) n-widetag-bits) closure-header-widetag)
 181                result 0 fun-pointer-lowtag))
 182     (loadw temp function closure-fun-slot fun-pointer-lowtag)
 183     (storew temp result closure-fun-slot fun-pointer-lowtag))))
 184
 185 ;;; The compiler likes to be able to directly make value cells.
 186 (define-vop (make-value-cell)
 187   (:args (value :scs (descriptor-reg any-reg) :to :result))
 188   (:results (result :scs (descriptor-reg) :from :eval))
 189   (:info stack-allocate-p)
 190   (:node-var node)
 191   (:generator 10
 192     (with-fixed-allocation
 193         (result value-cell-widetag value-cell-size node stack-allocate-p)
 194       (storew value result value-cell-value-slot other-pointer-lowtag))))
 195 \f
 196 ;;;; automatic allocators for primitive objects
 197
 198 (define-vop (make-unbound-marker)
 199   (:args)
 200   (:results (result :scs (descriptor-reg any-reg)))
 201   (:generator 1
 202     (inst mov result unbound-marker-widetag)))
 203
 204 (define-vop (make-funcallable-instance-tramp)
 205   (:args)
 206   (:results (result :scs (any-reg)))
 207   (:generator 1
 208     (inst lea result (make-fixup 'funcallable-instance-tramp :assembly-routine))))
 209
 210 (define-vop (fixed-alloc)
 211   (:args)
 212   (:info name words type lowtag stack-allocate-p)
 213   (:ignore name)
 214   (:results (result :scs (descriptor-reg)))
 215   (:node-var node)
 216   (:generator 50
 217     ;; We special case the allocation of conses, because they're
 218     ;; extremely common and because the pseudo-atomic sequence on x86
 219     ;; is relatively heavyweight.  However, if the user asks for top
 220     ;; speed, we accomodate him.  The primary reason that we don't
 221     ;; also check for (< SPEED SPACE) is because we want the space
 222     ;; savings that these out-of-line allocation routines bring whilst
 223     ;; compiling SBCL itself.  --njf, 2006-07-08
 224     (if (and (not stack-allocate-p)
 225              (= lowtag list-pointer-lowtag) (policy node (< speed 3)))
 226         (let ((dst
 227                ;; FIXME: out-of-line dx-allocation
 228                #.(loop for offset in *dword-regs*
 229                     collect `(,offset
 230                               ',(intern (format nil "ALLOCATE-CONS-TO-~A"
 231                                                 (svref *dword-register-names*
 232                                                        offset)))) into cases
 233                     finally (return `(case (tn-offset result)
 234                                        ,@cases)))))
 235           (aver (null type))
 236           (inst call (make-fixup dst :assembly-routine)))
 237         (maybe-pseudo-atomic stack-allocate-p
 238          (allocation result (pad-data-block words) node stack-allocate-p lowtag)
 239          (when type
 240            (storew (logior (ash (1- words) n-widetag-bits) type)
 241                    result
 242                    0
 243                    lowtag))))))
 244
 245 (define-vop (var-alloc)
 246   (:args (extra :scs (any-reg)))
 247   (:arg-types positive-fixnum)
 248   (:info name words type lowtag)
 249   (:ignore name)
 250   (:results (result :scs (descriptor-reg) :from (:eval 1)))
 251   (:temporary (:sc any-reg :from :eval :to (:eval 1)) bytes)
 252   (:temporary (:sc any-reg :from :eval :to :result) header)
 253   (:node-var node)
 254   (:generator 50
 255     (inst lea bytes
 256           (make-ea :dword :base extra :disp (* (1+ words) n-word-bytes)))
 257     (inst mov header bytes)
 258     (inst shl header (- n-widetag-bits 2)) ; w+1 to length field
 259     (inst lea header                    ; (w-1 << 8) | type
 260           (make-ea :dword :base header :disp (+ (ash -2 n-widetag-bits) type)))
 261     (inst and bytes (lognot lowtag-mask))
 262     (pseudo-atomic
 263      (allocation result bytes node)
 264      (inst lea result (make-ea :byte :base result :disp lowtag))
 265      (storew header result 0 lowtag))))