src/compiler/alpha/system.lisp

   1 ;;;; Alpha VM definitions of various system hacking operations
   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 ;;;; type frobbing VOPs
  15
  16 (define-vop (lowtag-of)
  17   (:translate lowtag-of)
  18   (:policy :fast-safe)
  19   (:args (object :scs (any-reg descriptor-reg)))
  20   (:results (result :scs (unsigned-reg)))
  21   (:result-types positive-fixnum)
  22   (:generator 1
  23     (inst and object lowtag-mask result)))
  24
  25 (define-vop (widetag-of)
  26   (:translate widetag-of)
  27   (:policy :fast-safe)
  28   (:args (object :scs (descriptor-reg)))
  29   (:temporary (:scs (non-descriptor-reg)) ndescr)
  30   (:results (result :scs (unsigned-reg)))
  31   (:result-types positive-fixnum)
  32   (:generator 6
  33     ;; Pick off objects with headers.
  34     (inst and object lowtag-mask result)
  35     (inst cmpeq result other-pointer-lowtag ndescr)
  36     (inst bne ndescr other-ptr)
  37     (inst cmpeq result fun-pointer-lowtag ndescr)
  38     (inst bne ndescr function-ptr)
  39
  40     ;; Pick off structure and list pointers.
  41     (inst blbs object done)
  42
  43     ;; Pick off fixnums.
  44     (inst and object fixnum-tag-mask result)
  45     (inst beq result done)
  46
  47     ;; Must be an other immediate.
  48     (inst and object widetag-mask result)
  49     (inst br zero-tn done)
  50
  51     FUNCTION-PTR
  52     (load-type result object (- fun-pointer-lowtag))
  53     (inst br zero-tn done)
  54
  55     OTHER-PTR
  56     (load-type result object (- other-pointer-lowtag))
  57
  58     DONE))
  59
  60 (define-vop (fun-subtype)
  61   (:translate fun-subtype)
  62   (:policy :fast-safe)
  63   (:args (function :scs (descriptor-reg)))
  64   (:results (result :scs (unsigned-reg)))
  65   (:result-types positive-fixnum)
  66   (:generator 6
  67     (load-type result function (- fun-pointer-lowtag))))
  68
  69 (define-vop (set-fun-subtype)
  70   (:translate (setf fun-subtype))
  71   (:policy :fast-safe)
  72   (:args (type :scs (unsigned-reg) :target result)
  73          (function :scs (descriptor-reg)))
  74   (:arg-types positive-fixnum *)
  75   (:temporary (:scs (non-descriptor-reg)) temp)
  76   (:results (result :scs (unsigned-reg)))
  77   (:result-types positive-fixnum)
  78   (:generator 6
  79     (inst ldl temp (- fun-pointer-lowtag) function)
  80     (inst and temp #xff temp)
  81     (inst bis type temp temp)
  82     (inst stl temp (- fun-pointer-lowtag) function)
  83     (move type result)))
  84
  85
  86 (define-vop (get-header-data)
  87   (:translate get-header-data)
  88   (:policy :fast-safe)
  89   (:args (x :scs (descriptor-reg)))
  90   (:results (res :scs (unsigned-reg)))
  91   (:result-types positive-fixnum)
  92   (:generator 6
  93     (loadw res x 0 other-pointer-lowtag)
  94     (inst srl res n-widetag-bits res)))
  95
  96 (define-vop (get-closure-length)
  97   (:translate get-closure-length)
  98   (:policy :fast-safe)
  99   (:args (x :scs (descriptor-reg)))
 100   (:results (res :scs (unsigned-reg)))
 101   (:result-types positive-fixnum)
 102   (:generator 6
 103     (loadw res x 0 fun-pointer-lowtag)
 104     (inst srl res n-widetag-bits res)))
 105
 106 (define-vop (set-header-data)
 107   (:translate set-header-data)
 108   (:policy :fast-safe)
 109   (:args (x :scs (descriptor-reg) :target res)
 110          (data :scs (any-reg immediate zero)))
 111   (:arg-types * positive-fixnum)
 112   (:results (res :scs (descriptor-reg)))
 113   (:temporary (:scs (non-descriptor-reg)) t1 t2)
 114   (:generator 6
 115     (loadw t1 x 0 other-pointer-lowtag)
 116     (inst and t1 widetag-mask t1)
 117     (sc-case data
 118       (any-reg
 119        (inst sll data (- n-widetag-bits 2) t2)
 120        (inst bis t1 t2 t1))
 121       (immediate
 122        (let ((c (ash (tn-value data) n-widetag-bits)))
 123          (cond ((<= 0 c (1- (ash 1 8)))
 124                 (inst bis t1 c t1))
 125                (t
 126                 (inst li c t2)
 127                 (inst bis t1 t2 t1)))))
 128       (zero))
 129     (storew t1 x 0 other-pointer-lowtag)
 130     (move x res)))
 131
 132 (define-vop (pointer-hash)
 133   (:translate pointer-hash)
 134   (:args (ptr :scs (any-reg descriptor-reg)))
 135   (:results (res :scs (any-reg descriptor-reg)))
 136   (:policy :fast-safe)
 137   (:generator 1
 138     ;; FIXME: It would be better if this would mask the lowtag,
 139     ;; and shift the result into a positive fixnum like on x86.
 140     (inst sll ptr 35 res)
 141     (inst srl res 33 res)))
 142
 143 (define-vop (make-other-immediate-type)
 144   (:args (val :scs (any-reg descriptor-reg))
 145          (type :scs (any-reg descriptor-reg immediate)
 146                :target temp))
 147   (:results (res :scs (any-reg descriptor-reg)))
 148   (:temporary (:scs (non-descriptor-reg)) temp)
 149   (:generator 2
 150     (sc-case type
 151       ((immediate)
 152        (inst sll val n-widetag-bits temp)
 153        (inst bis temp (tn-value type) res))
 154       (t
 155        (inst sra type n-fixnum-tag-bits temp)
 156        (inst sll val (- n-widetag-bits n-fixnum-tag-bits) res)
 157        (inst bis res temp res)))))
 158
 159 \f
 160 ;;;; allocation
 161
 162 (define-vop (dynamic-space-free-pointer)
 163   (:results (int :scs (sap-reg)))
 164   (:result-types system-area-pointer)
 165   (:translate dynamic-space-free-pointer)
 166   (:policy :fast-safe)
 167   (:generator 1
 168     (move alloc-tn int)))
 169
 170 (define-vop (binding-stack-pointer-sap)
 171   (:results (int :scs (sap-reg)))
 172   (:result-types system-area-pointer)
 173   (:translate binding-stack-pointer-sap)
 174   (:policy :fast-safe)
 175   (:generator 1
 176     (move bsp-tn int)))
 177
 178 (define-vop (control-stack-pointer-sap)
 179   (:results (int :scs (sap-reg)))
 180   (:result-types system-area-pointer)
 181   (:translate control-stack-pointer-sap)
 182   (:policy :fast-safe)
 183   (:generator 1
 184     (move csp-tn int)))
 185
 186 \f
 187 ;;;; code object frobbing
 188
 189 (define-vop (code-instructions)
 190   (:translate code-instructions)
 191   (:policy :fast-safe)
 192   (:args (code :scs (descriptor-reg)))
 193   (:temporary (:scs (non-descriptor-reg)) ndescr)
 194   (:results (sap :scs (sap-reg)))
 195   (:result-types system-area-pointer)
 196   (:generator 10
 197     (loadw ndescr code 0 other-pointer-lowtag)
 198     (inst srl ndescr n-widetag-bits ndescr)
 199     (inst sll ndescr word-shift ndescr)
 200     (inst subq ndescr other-pointer-lowtag ndescr)
 201     (inst addq code ndescr sap)))
 202
 203 (define-vop (compute-fun)
 204   (:args (code :scs (descriptor-reg))
 205          (offset :scs (signed-reg unsigned-reg)))
 206   (:arg-types * positive-fixnum)
 207   (:results (func :scs (descriptor-reg)))
 208   (:temporary (:scs (non-descriptor-reg)) ndescr)
 209   (:generator 10
 210     (loadw ndescr code 0 other-pointer-lowtag)
 211     (inst srl ndescr n-widetag-bits ndescr)
 212     (inst sll ndescr word-shift ndescr)
 213     (inst addq ndescr offset ndescr)
 214     (inst subq ndescr (- other-pointer-lowtag fun-pointer-lowtag) ndescr)
 215     (inst addq code ndescr func)))
 216 \f
 217 ;;;; other random VOPs.
 218
 219 (defknown sb!unix::receive-pending-interrupt () (values))
 220 (define-vop (sb!unix::receive-pending-interrupt)
 221   (:policy :fast-safe)
 222   (:translate sb!unix::receive-pending-interrupt)
 223   (:generator 1
 224     (inst gentrap pending-interrupt-trap)))
 225
 226
 227 (define-vop (halt)
 228   (:generator 1
 229     (inst gentrap halt-trap)))
 230
 231 (define-vop (istream-memory-barrier)
 232   (:generator 1
 233     (inst imb)))
 234 \f
 235 ;;;; dynamic vop count collection support
 236
 237 (define-vop (count-me)
 238   (:args (count-vector :scs (descriptor-reg)))
 239   (:info index)
 240   (:temporary (:scs (non-descriptor-reg)) count)
 241   (:generator 1
 242     (let ((offset
 243            (- (* (+ index vector-data-offset) n-word-bytes)
 244               other-pointer-lowtag)))
 245       (inst ldl count offset count-vector)
 246       (inst addq count 1 count)
 247       (inst stl count offset count-vector))))