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