src/compiler/x86-64/alloc.lisp

   1 ;;;; allocation VOPs for the x86-64
   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))
  74          (length :scs (any-reg))
  75          (words :scs (any-reg)))
  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     (inst lea result (make-ea :byte :base words :disp
  83                               (+ (1- (ash 1 n-lowtag-bits))
  84                                  (* vector-data-offset n-word-bytes))))
  85     (inst and result (lognot lowtag-mask))
  86     (pseudo-atomic
  87       (allocation result result)
  88       (inst lea result (make-ea :byte :base result :disp other-pointer-lowtag))
  89       (storew type result 0 other-pointer-lowtag)
  90       (storew length result vector-length-slot other-pointer-lowtag))))
  91
  92 (define-vop (allocate-vector-on-stack)
  93   (:args (type :scs (unsigned-reg))
  94          (length :scs (any-reg))
  95          (words :scs (any-reg) :target ecx))
  96   (:temporary (:sc any-reg :offset ecx-offset :from (:argument 2)) ecx)
  97   (:temporary (:sc any-reg :offset eax-offset :from (:argument 2)) zero)
  98   (:temporary (:sc any-reg :offset edi-offset :from (:argument 0)) res)
  99   (:results (result :scs (descriptor-reg) :from :load))
 100   (:arg-types positive-fixnum
 101               positive-fixnum
 102               positive-fixnum)
 103   (:translate allocate-vector)
 104   (:policy :fast-safe)
 105   (:node-var node)
 106   (:generator 100
 107     (inst lea result (make-ea :byte :base words :disp
 108                               (+ (1- (ash 1 n-lowtag-bits))
 109                                  (* vector-data-offset n-word-bytes))))
 110     (inst and result (lognot lowtag-mask))
 111     ;; FIXME: It would be good to check for stack overflow here.
 112     (move ecx words)
 113     (inst shr ecx n-fixnum-tag-bits)
 114     (allocation result result node t other-pointer-lowtag)
 115     (inst cld)
 116     (inst lea res
 117           (make-ea :byte :base result :disp (- (* vector-data-offset n-word-bytes)
 118                                                other-pointer-lowtag)))
 119     (storew type result 0 other-pointer-lowtag)
 120     (storew length result vector-length-slot other-pointer-lowtag)
 121     (zeroize zero)
 122     (inst rep)
 123     (inst stos zero)))
 124
 125 (in-package "SB!VM")
 126 \f
 127 (define-vop (make-fdefn)
 128   (:policy :fast-safe)
 129   (:translate make-fdefn)
 130   (:args (name :scs (descriptor-reg) :to :eval))
 131   (:results (result :scs (descriptor-reg) :from :argument))
 132   (:node-var node)
 133   (:generator 37
 134     (with-fixed-allocation (result fdefn-widetag fdefn-size node)
 135       (storew name result fdefn-name-slot other-pointer-lowtag)
 136       (storew nil-value result fdefn-fun-slot other-pointer-lowtag)
 137       (storew (make-fixup "undefined_tramp" :foreign)
 138               result fdefn-raw-addr-slot other-pointer-lowtag))))
 139
 140 (define-vop (make-closure)
 141   (:args (function :to :save :scs (descriptor-reg)))
 142   (:info length stack-allocate-p)
 143   (:temporary (:sc any-reg) temp)
 144   (:results (result :scs (descriptor-reg)))
 145   (:node-var node)
 146   (:generator 10
 147    (maybe-pseudo-atomic stack-allocate-p
 148     (let ((size (+ length closure-info-offset)))
 149       (allocation result (pad-data-block size) node stack-allocate-p
 150                   fun-pointer-lowtag)
 151       (storew (logior (ash (1- size) n-widetag-bits) closure-header-widetag)
 152               result 0 fun-pointer-lowtag))
 153     (loadw temp function closure-fun-slot fun-pointer-lowtag)
 154     (storew temp result closure-fun-slot fun-pointer-lowtag))))
 155
 156 ;;; The compiler likes to be able to directly make value cells.
 157 (define-vop (make-value-cell)
 158   (:args (value :scs (descriptor-reg any-reg) :to :result))
 159   (:results (result :scs (descriptor-reg) :from :eval))
 160   (:info stack-allocate-p)
 161   (:node-var node)
 162   (:generator 10
 163     (with-fixed-allocation
 164         (result value-cell-header-widetag value-cell-size node stack-allocate-p)
 165       (storew value result value-cell-value-slot other-pointer-lowtag))))
 166 \f
 167 ;;;; automatic allocators for primitive objects
 168
 169 (define-vop (make-unbound-marker)
 170   (:args)
 171   (:results (result :scs (any-reg)))
 172   (:generator 1
 173     (inst mov result unbound-marker-widetag)))
 174
 175 (define-vop (make-funcallable-instance-tramp)
 176   (:args)
 177   (:results (result :scs (any-reg)))
 178   (:generator 1
 179     (inst lea result (make-fixup "funcallable_instance_tramp" :foreign))))
 180
 181 (define-vop (fixed-alloc)
 182   (:args)
 183   (:info name words type lowtag stack-allocate-p)
 184   (:ignore name)
 185   (:results (result :scs (descriptor-reg)))
 186   (:node-var node)
 187   (:generator 50
 188     (maybe-pseudo-atomic stack-allocate-p
 189      (allocation result (pad-data-block words) node stack-allocate-p lowtag)
 190      (when type
 191        (storew (logior (ash (1- words) n-widetag-bits) type)
 192                result
 193                0
 194                lowtag)))))
 195
 196 (define-vop (var-alloc)
 197   (:args (extra :scs (any-reg)))
 198   (:arg-types positive-fixnum)
 199   (:info name words type lowtag)
 200   (:ignore name)
 201   (:results (result :scs (descriptor-reg) :from (:eval 1)))
 202   (:temporary (:sc any-reg :from :eval :to (:eval 1)) bytes)
 203   (:temporary (:sc any-reg :from :eval :to :result) header)
 204   (:node-var node)
 205   (:generator 50
 206     (inst lea bytes
 207           (make-ea :qword :base extra :disp (* (1+ words) n-word-bytes)))
 208     (inst mov header bytes)
 209     (inst shl header (- n-widetag-bits 3)) ; w+1 to length field
 210     (inst lea header                    ; (w-1 << 8) | type
 211           (make-ea :qword :base header :disp (+ (ash -2 n-widetag-bits) type)))
 212     (inst and bytes (lognot lowtag-mask))
 213     (pseudo-atomic
 214      (allocation result bytes node)
 215      (inst lea result (make-ea :byte :base result :disp lowtag))
 216      (storew header result 0 lowtag))))
 217
 218 (define-vop (%make-symbol)
 219   (:policy :fast-safe)
 220   (:translate %make-symbol)
 221   (:args (name :scs (descriptor-reg) :to :eval))
 222   (:temporary (:sc unsigned-reg :from :eval) temp)
 223   (:results (result :scs (descriptor-reg) :from :argument))
 224   (:node-var node)
 225   (:generator 37
 226     (with-fixed-allocation (result symbol-header-widetag symbol-size node)
 227       (storew name result symbol-name-slot other-pointer-lowtag)
 228       (storew unbound-marker-widetag
 229               result
 230               symbol-value-slot
 231               other-pointer-lowtag)
 232       ;; Set up a random hash value for the symbol. Perhaps the object
 233       ;; address could be used for even faster and smaller code!
 234       ;; FIXME: We don't mind the symbol hash not being repeatable, so
 235       ;; we might as well add in the object address here, too. (Adding entropy
 236       ;; is good, even if ANSI doesn't understand that.)
 237       (inst imul temp
 238             (make-fixup "fast_random_state" :foreign)
 239             1103515245)
 240       (inst add temp 12345)
 241       (inst mov (make-fixup "fast_random_state" :foreign)
 242             temp)
 243       ;; We want a positive fixnum for the hash value, so discard the LS bits.
 244       ;;
 245       ;; FIXME: OK, who wants to tell me (CSR) why these two
 246       ;; instructions aren't replaced by (INST AND TEMP #x8FFFFFFC)?
 247       ;; Are the following two instructions actually faster?  Does the
 248       ;; difference in behaviour really matter?
 249       (inst shr temp 1)
 250       (inst and temp #xfffffffc)
 251       (storew temp result symbol-hash-slot other-pointer-lowtag)
 252       (storew nil-value result symbol-plist-slot other-pointer-lowtag)
 253       (storew nil-value result symbol-package-slot other-pointer-lowtag))))