src/compiler/x86-64/subprim.lisp

   1 ;;;; linkage information for standard static functions, and
   2 ;;;; miscellaneous VOPs
   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 \f
  15 ;;;; LENGTH
  16
  17 (define-vop (length/list)
  18   (:translate length)
  19   (:args (object :scs (descriptor-reg control-stack) :target ptr))
  20   (:arg-types list)
  21   (:temporary (:sc dword-reg :offset eax-offset) eax)
  22   (:temporary (:sc descriptor-reg :from (:argument 0)) ptr)
  23   (:results (count :scs (any-reg)))
  24   (:result-types positive-fixnum)
  25   (:policy :fast-safe)
  26   (:vop-var vop)
  27   (:save-p :compute-only)
  28   (:ignore eax)
  29   (:generator 40
  30     ;; Move OBJECT into a temp we can bash on, and initialize the count.
  31     (move ptr object)
  32     (zeroize count)
  33     ;; If we are starting with NIL, then it's really easy.
  34     (inst cmp ptr nil-value)
  35     (inst jmp :e DONE)
  36     ;; Note: we don't have to test to see whether the original argument is a
  37     ;; list, because this is a :fast-safe vop.
  38     LOOP
  39     ;; Get the CDR and boost the count.
  40     (loadw ptr ptr cons-cdr-slot list-pointer-lowtag)
  41     (inst add count (fixnumize 1))
  42     ;; If we hit NIL, then we are done.
  43     (inst cmp ptr nil-value)
  44     (inst jmp :e DONE)
  45     ;; Otherwise, check to see whether we hit the end of a dotted list. If
  46     ;; not, loop back for more.
  47     (%test-lowtag ptr LOOP nil list-pointer-lowtag)
  48     ;; It's dotted all right. Flame out.
  49     (error-call vop 'object-not-list-error ptr)
  50     ;; We be done.
  51     DONE))
  52
  53 (define-vop (fast-length/list)
  54   (:translate length)
  55   (:args (object :scs (descriptor-reg control-stack) :target ptr))
  56   (:arg-types list)
  57   (:temporary (:sc descriptor-reg :from (:argument 0)) ptr)
  58   (:results (count :scs (any-reg)))
  59   (:result-types positive-fixnum)
  60   (:policy :fast)
  61   (:vop-var vop)
  62   (:save-p :compute-only)
  63   (:generator 30
  64     ;; Get a copy of OBJECT in a register we can bash on, and
  65     ;; initialize COUNT.
  66     (move ptr object)
  67     (zeroize count)
  68     ;; If we are starting with NIL, we be done.
  69     (inst cmp ptr nil-value)
  70     (inst jmp :e DONE)
  71     ;; Indirect the next cons cell, and boost the count.
  72     LOOP
  73     (loadw ptr ptr cons-cdr-slot list-pointer-lowtag)
  74     (inst add count (fixnumize 1))
  75     ;; If we aren't done, go back for more.
  76     (inst cmp ptr nil-value)
  77     (inst jmp :ne LOOP)
  78     DONE))
  79
  80 (define-static-fun length (object) :translate length)
  81 (define-static-fun %coerce-callable-to-fun (callable)
  82   :translate %coerce-callable-to-fun)