src/compiler/ppc/nlx.lisp

   1 ;;;; the PPC definitions of VOPs used for non-local exit (throw,
   2 ;;;; lexical exit, etc.)
   3
   4 ;;;; This software is part of the SBCL system. See the README file for
   5 ;;;; more information.
   6 ;;;;
   7 ;;;; This software is derived from the CMU CL system, which was
   8 ;;;; written at Carnegie Mellon University and released into the
   9 ;;;; public domain. The software is in the public domain and is
  10 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  11 ;;;; files for more information.
  12
  13 (in-package "SB!VM")
  14
  15 ;;; Make a TN for the argument count passing location for a
  16 ;;; non-local entry.
  17 (defun make-nlx-entry-arg-start-location ()
  18   (make-wired-tn *fixnum-primitive-type* immediate-arg-scn ocfp-offset))
  19
  20 \f
  21 ;;; These VOPs are used in the reentered function to restore the
  22 ;;; appropriate dynamic environment. Currently we only save the
  23 ;;; CURRENT-CATCH and binding stack pointer. We don't need to
  24 ;;; save/restore the current unwind-protect, since UNWIND-PROTECTs are
  25 ;;; implicitly processed during unwinding. If there were any
  26 ;;; additional stacks, then this would be the place to restore the top
  27 ;;; pointers.
  28
  29 (define-vop (save-dynamic-state)
  30   (:results (catch :scs (descriptor-reg))
  31             (nfp :scs (descriptor-reg))
  32             (nsp :scs (descriptor-reg)))
  33   (:vop-var vop)
  34   (:generator 13
  35     (load-tl-symbol-value catch *current-catch-block*)
  36     (let ((cur-nfp (current-nfp-tn vop)))
  37       (when cur-nfp
  38         (move nfp cur-nfp)))
  39     (move nsp nsp-tn)))
  40
  41 (define-vop (restore-dynamic-state)
  42   (:args (catch :scs (descriptor-reg))
  43          (nfp :scs (descriptor-reg))
  44          (nsp :scs (descriptor-reg)))
  45   #!+sb-thread (:temporary (:scs (any-reg)) temp)
  46   (:vop-var vop)
  47   (:generator 10
  48     (store-tl-symbol-value catch *current-catch-block* temp)
  49     (let ((cur-nfp (current-nfp-tn vop)))
  50       (when cur-nfp
  51         (move cur-nfp nfp)))
  52     (move nsp-tn nsp)))
  53
  54 (define-vop (current-stack-pointer)
  55   (:results (res :scs (any-reg descriptor-reg)))
  56   (:generator 1
  57     (move res csp-tn)))
  58
  59 (define-vop (current-binding-pointer)
  60   (:results (res :scs (any-reg descriptor-reg)))
  61   (:generator 1
  62     (move res bsp-tn)))
  63
  64
  65 \f
  66 ;;;; Unwind block hackery:
  67
  68 ;;; Compute the address of the catch block from its TN, then store into the
  69 ;;; block the current Fp, Env, Unwind-Protect, and the entry PC.
  70 ;;;
  71 (define-vop (make-unwind-block)
  72   (:args (tn))
  73   (:info entry-label)
  74   (:results (block :scs (any-reg)))
  75   (:temporary (:scs (descriptor-reg)) temp)
  76   (:temporary (:scs (non-descriptor-reg)) ndescr)
  77   (:generator 22
  78     (inst addi block cfp-tn (* (tn-offset tn) n-word-bytes))
  79     (load-tl-symbol-value temp *current-unwind-protect-block*)
  80     (storew temp block unwind-block-current-uwp-slot)
  81     (storew cfp-tn block unwind-block-current-cont-slot)
  82     (storew code-tn block unwind-block-current-code-slot)
  83     (inst compute-lra-from-code temp code-tn entry-label ndescr)
  84     (storew temp block catch-block-entry-pc-slot)))
  85
  86
  87 ;;; Like Make-Unwind-Block, except that we also store in the specified tag, and
  88 ;;; link the block into the Current-Catch list.
  89 ;;;
  90 (define-vop (make-catch-block)
  91   (:args (tn)
  92          (tag :scs (any-reg descriptor-reg)))
  93   (:info entry-label)
  94   (:results (block :scs (any-reg)))
  95   (:temporary (:scs (descriptor-reg)) temp)
  96   (:temporary (:scs (descriptor-reg) :target block :to (:result 0)) result)
  97   (:temporary (:scs (non-descriptor-reg)) ndescr)
  98   (:generator 44
  99     (inst addi result cfp-tn (* (tn-offset tn) n-word-bytes))
 100     (load-tl-symbol-value temp *current-unwind-protect-block*)
 101     (storew temp result catch-block-current-uwp-slot)
 102     (storew cfp-tn result catch-block-current-cont-slot)
 103     (storew code-tn result catch-block-current-code-slot)
 104     (inst compute-lra-from-code temp code-tn entry-label ndescr)
 105     (storew temp result catch-block-entry-pc-slot)
 106
 107     (storew tag result catch-block-tag-slot)
 108     (load-tl-symbol-value temp *current-catch-block*)
 109     (storew temp result catch-block-previous-catch-slot)
 110     (store-tl-symbol-value result *current-catch-block* temp)
 111
 112     (move block result)))
 113
 114
 115 ;;; Just set the current unwind-protect to TN's address.  This instantiates an
 116 ;;; unwind block as an unwind-protect.
 117 ;;;
 118 (define-vop (set-unwind-protect)
 119   (:args (tn))
 120   (:temporary (:scs (descriptor-reg)) new-uwp)
 121   #!+sb-thread (:temporary (:scs (any-reg)) temp)
 122   (:generator 7
 123     (inst addi new-uwp cfp-tn (* (tn-offset tn) n-word-bytes))
 124     (store-tl-symbol-value new-uwp *current-unwind-protect-block* temp)))
 125
 126
 127 (define-vop (unlink-catch-block)
 128   (:temporary (:scs (any-reg)) block)
 129   #!+sb-thread (:temporary (:scs (any-reg)) temp)
 130   (:policy :fast-safe)
 131   (:translate %catch-breakup)
 132   (:generator 17
 133     (load-tl-symbol-value block *current-catch-block*)
 134     (loadw block block catch-block-previous-catch-slot)
 135     (store-tl-symbol-value block *current-catch-block* temp)))
 136
 137 (define-vop (unlink-unwind-protect)
 138   (:temporary (:scs (any-reg)) block)
 139   #!+sb-thread (:temporary (:scs (any-reg)) temp)
 140   (:policy :fast-safe)
 141   (:translate %unwind-protect-breakup)
 142   (:generator 17
 143     (load-tl-symbol-value block *current-unwind-protect-block*)
 144     (loadw block block unwind-block-current-uwp-slot)
 145     (store-tl-symbol-value block *current-unwind-protect-block* temp)))
 146
 147 \f
 148 ;;;; NLX entry VOPs:
 149
 150
 151 (define-vop (nlx-entry)
 152   (:args (sp) ; Note: we can't list an sc-restriction, 'cause any load vops
 153               ; would be inserted before the LRA.
 154          (start)
 155          (count))
 156   (:results (values :more t))
 157   (:temporary (:scs (descriptor-reg)) move-temp)
 158   (:info label nvals)
 159   (:save-p :force-to-stack)
 160   (:vop-var vop)
 161   (:generator 30
 162     (emit-return-pc label)
 163     (note-this-location vop :non-local-entry)
 164     (cond ((zerop nvals))
 165           ((= nvals 1)
 166            (let ((no-values (gen-label)))
 167              (inst cmpwi count 0)
 168              (move (tn-ref-tn values) null-tn)
 169              (inst beq no-values)
 170              (loadw (tn-ref-tn values) start)
 171              (emit-label no-values)))
 172           (t
 173            (collect ((defaults))
 174              (inst addic. count count (- (fixnumize 1)))
 175              (do ((i 0 (1+ i))
 176                   (tn-ref values (tn-ref-across tn-ref)))
 177                  ((null tn-ref))
 178                (let ((default-lab (gen-label))
 179                      (tn (tn-ref-tn tn-ref)))
 180                  (defaults (cons default-lab tn))
 181
 182                  (inst subi count count (fixnumize 1))
 183                  (inst blt default-lab)
 184                  (sc-case tn
 185                           ((descriptor-reg any-reg)
 186                            (loadw tn start i))
 187                           (control-stack
 188                            (loadw move-temp start i)
 189                            (store-stack-tn tn move-temp)))
 190                  (inst cmpwi count 0)))
 191
 192              (let ((defaulting-done (gen-label)))
 193
 194                (emit-label defaulting-done)
 195
 196                (assemble (*elsewhere*)
 197                  (dolist (def (defaults))
 198                    (emit-label (car def))
 199                    (let ((tn (cdr def)))
 200                      (sc-case tn
 201                               ((descriptor-reg any-reg)
 202                                (move tn null-tn))
 203                               (control-stack
 204                                (store-stack-tn tn null-tn)))))
 205                  (inst b defaulting-done))))))
 206     (load-stack-tn csp-tn sp)))
 207
 208
 209 (define-vop (nlx-entry-multiple)
 210   (:args (top :target result) (src) (count))
 211   ;; Again, no SC restrictions for the args, 'cause the loading would
 212   ;; happen before the entry label.
 213   (:info label)
 214   (:temporary (:scs (any-reg)) dst)
 215   (:temporary (:scs (descriptor-reg)) temp)
 216   (:results (result :scs (any-reg) :from (:argument 0))
 217             (num :scs (any-reg) :from (:argument 0)))
 218   (:save-p :force-to-stack)
 219   (:vop-var vop)
 220   (:generator 30
 221     (emit-return-pc label)
 222     (note-this-location vop :non-local-entry)
 223     (let ((loop (gen-label))
 224           (done (gen-label)))
 225
 226       ;; Setup results, and test for the zero value case.
 227       (load-stack-tn result top)
 228       (inst cmpwi count 0)
 229       (inst li num 0)
 230       (inst beq done)
 231
 232       ;; Compute dst as one slot down from result, because we inc the index
 233       ;; before we use it.
 234       (inst subi dst result 4)
 235
 236       ;; Copy stuff down the stack.
 237       (emit-label loop)
 238       (inst lwzx temp src num)
 239       (inst addi num num (fixnumize 1))
 240       (inst cmpw num count)
 241       (inst stwx temp dst num)
 242       (inst bne loop)
 243
 244       ;; Reset the CSP.
 245       (emit-label done)
 246       (inst add csp-tn result num))))
 247
 248
 249 ;;; This VOP is just to force the TNs used in the cleanup onto the stack.
 250 ;;;
 251 (define-vop (uwp-entry)
 252   (:info label)
 253   (:save-p :force-to-stack)
 254   (:results (block) (start) (count))
 255   (:ignore block start count)
 256   (:vop-var vop)
 257   (:generator 0
 258     (emit-return-pc label)
 259     (note-this-location vop :non-local-entry)))
 260