src/compiler/mips/values.lisp

   1 ;;;; the MIPS implementation of unknown-values VOPs
   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
  14 (define-vop (reset-stack-pointer)
  15   (:args (ptr :scs (any-reg)))
  16   (:generator 1
  17     (move csp-tn ptr)))
  18
  19 (define-vop (%%pop-dx)
  20   (:args (ptr :scs (any-reg)))
  21   (:ignore ptr)
  22   (:generator 1
  23     (bug "VOP %%POP-DX is not implemented.")))
  24
  25 (define-vop (%%nip-dx)
  26   (:args (last-nipped-ptr :scs (any-reg) :target dest)
  27          (last-preserved-ptr :scs (any-reg) :target src)
  28          (moved-ptrs :scs (any-reg) :more t))
  29   (:results (r-moved-ptrs :scs (any-reg) :more t))
  30   (:temporary (:sc any-reg) src)
  31   (:temporary (:sc any-reg) dest)
  32   (:temporary (:sc non-descriptor-reg) temp)
  33   (:ignore r-moved-ptrs
  34            last-nipped-ptr last-preserved-ptr moved-ptrs
  35            src dest temp)
  36   (:generator 1
  37     (bug "VOP %%NIP-DX is not implemented.")))
  38
  39 (define-vop (%%nip-values)
  40   (:args (last-nipped-ptr :scs (any-reg) :target dest)
  41          (last-preserved-ptr :scs (any-reg) :target src)
  42          (moved-ptrs :scs (any-reg) :more t))
  43   (:results (r-moved-ptrs :scs (any-reg) :more t))
  44   (:temporary (:sc any-reg) src)
  45   (:temporary (:sc any-reg) dest)
  46   (:temporary (:sc non-descriptor-reg) temp)
  47   (:ignore r-moved-ptrs)
  48   (:generator 1
  49     (move src last-preserved-ptr)
  50     (move dest last-nipped-ptr)
  51     (inst sltu temp src csp-tn)
  52     (inst beq temp DONE)
  53     (inst nop) ; not strictly necessary
  54     LOOP
  55     (loadw temp src)
  56     (inst addu dest dest n-word-bytes)
  57     (inst addu src src n-word-bytes)
  58     (storew temp dest -1)
  59     (inst sltu temp src csp-tn)
  60     (inst bne temp LOOP)
  61     (inst nop)
  62     DONE
  63     (move csp-tn dest)
  64     (inst subu src src dest)
  65     (loop for moved = moved-ptrs then (tn-ref-across moved)
  66           while moved
  67           do (sc-case (tn-ref-tn moved)
  68                ((descriptor-reg any-reg)
  69                 (inst subu (tn-ref-tn moved) (tn-ref-tn moved) src))
  70                ((control-stack)
  71                 (load-stack-tn temp (tn-ref-tn moved))
  72                 (inst subu temp temp src)
  73                 (store-stack-tn (tn-ref-tn moved) temp))))))
  74
  75 ;;; Push some values onto the stack, returning the start and number of values
  76 ;;; pushed as results.  It is assumed that the Vals are wired to the standard
  77 ;;; argument locations.  Nvals is the number of values to push.
  78 ;;;
  79 ;;; The generator cost is pseudo-random.  We could get it right by defining a
  80 ;;; bogus SC that reflects the costs of the memory-to-memory moves for each
  81 ;;; operand, but this seems unworthwhile.
  82 ;;;
  83 (define-vop (push-values)
  84   (:args
  85    (vals :more t))
  86   (:results
  87    (start :scs (any-reg))
  88    (count :scs (any-reg)))
  89   (:info nvals)
  90   (:temporary (:scs (descriptor-reg)) temp)
  91   (:temporary (:scs (descriptor-reg)
  92                :to (:result 0)
  93                :target start)
  94               start-temp)
  95   (:generator 20
  96     (move start-temp csp-tn)
  97     (inst addu csp-tn csp-tn (* nvals n-word-bytes))
  98     (do ((val vals (tn-ref-across val))
  99          (i 0 (1+ i)))
 100         ((null val))
 101       (let ((tn (tn-ref-tn val)))
 102         (sc-case tn
 103           (descriptor-reg
 104            (storew tn start-temp i))
 105           (control-stack
 106            (load-stack-tn temp tn)
 107            (storew temp start-temp i)))))
 108     (move start start-temp)
 109     (inst li count (fixnumize nvals))))
 110
 111 ;;; Push a list of values on the stack, returning Start and Count as used in
 112 ;;; unknown values continuations.
 113 (define-vop (values-list)
 114   (:args (arg :scs (descriptor-reg) :target list))
 115   (:arg-types list)
 116   (:policy :fast-safe)
 117   (:results (start :scs (any-reg))
 118             (count :scs (any-reg)))
 119   (:temporary (:scs (descriptor-reg) :type list :from (:argument 0)) list)
 120   (:temporary (:scs (descriptor-reg)) temp)
 121   (:temporary (:scs (non-descriptor-reg)) ndescr)
 122   (:vop-var vop)
 123   (:save-p :compute-only)
 124   (:generator 0
 125     (move list arg)
 126     (move start csp-tn)
 127
 128     LOOP
 129     (inst beq list null-tn done)
 130     (loadw temp list cons-car-slot list-pointer-lowtag)
 131     (loadw list list cons-cdr-slot list-pointer-lowtag)
 132     (inst addu csp-tn csp-tn n-word-bytes)
 133     (storew temp csp-tn -1)
 134     (inst and ndescr list lowtag-mask)
 135     (inst xor ndescr list-pointer-lowtag)
 136     (inst beq ndescr loop)
 137     (inst nop)
 138     (error-call vop 'bogus-arg-to-values-list-error list)
 139
 140     DONE
 141     (inst subu count csp-tn start)))
 142
 143 ;;; Copy the more arg block to the top of the stack so we can use them
 144 ;;; as function arguments.
 145 (define-vop (%more-arg-values)
 146   (:args (context :scs (descriptor-reg any-reg) :target src)
 147          (skip :scs (any-reg zero immediate))
 148          (num :scs (any-reg) :target count))
 149   (:arg-types * positive-fixnum positive-fixnum)
 150   (:temporary (:sc any-reg :from (:argument 0)) src)
 151   (:temporary (:sc any-reg :from (:argument 2)) dst)
 152   (:temporary (:sc descriptor-reg :from (:argument 1)) temp)
 153   (:results (start :scs (any-reg))
 154             (count :scs (any-reg)))
 155   (:generator 20
 156     (sc-case skip
 157       (zero
 158        (move src context))
 159       (immediate
 160        (inst addu src context (* (tn-value skip) n-word-bytes)))
 161       (any-reg
 162        (inst addu src context skip)))
 163     (move count num)
 164     (inst beq num done)
 165     (move start csp-tn t)
 166     (move dst csp-tn)
 167     (inst addu csp-tn count)
 168     LOOP
 169     (inst lw temp src)
 170     (inst addu src n-word-bytes)
 171     (inst addu dst n-word-bytes)
 172     (inst bne dst csp-tn loop)
 173     (inst sw temp dst (- n-word-bytes))
 174     DONE))