src/assembly/arm64/array.lisp

   1 ;;;; various array operations that are too expensive (in space) to do
   2 ;;;; inline
   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 (define-assembly-routine (allocate-vector-on-heap
  16                           (:policy :fast-safe)
  17                           (:arg-types positive-fixnum
  18                                       positive-fixnum
  19                                       positive-fixnum))
  20     ((:arg type any-reg r0-offset)
  21      (:arg length any-reg r1-offset)
  22      (:arg words any-reg r2-offset)
  23      (:res result descriptor-reg r0-offset)
  24
  25      (:temp ndescr non-descriptor-reg nl2-offset)
  26      (:temp pa-flag non-descriptor-reg nl3-offset)
  27      (:temp lra-save non-descriptor-reg nl5-offset)
  28      (:temp vector descriptor-reg r8-offset)
  29      (:temp lr interior-reg lr-offset))
  30   (pseudo-atomic (pa-flag)
  31     (inst lsl ndescr words (- word-shift n-fixnum-tag-bits))
  32     (inst add ndescr ndescr (* (1+ vector-data-offset) n-word-bytes))
  33     (inst and ndescr ndescr (bic-mask lowtag-mask)) ; double-word align
  34     (move lra-save lr) ;; The call to alloc_tramp will overwrite LR
  35     (allocation vector ndescr other-pointer-lowtag :flag-tn pa-flag
  36                                                    :lip nil) ;; keep LR intact as per above
  37
  38     (move lr lra-save)
  39     (inst lsr ndescr type n-fixnum-tag-bits)
  40     (storew ndescr vector 0 other-pointer-lowtag)
  41     ;; Touch the last element, to ensure that null-terminated strings
  42     ;; passed to C do not cause a WP violation in foreign code.
  43     ;; Do that before storing length, since nil-arrays don't have any
  44     ;; space, but may have non-zero length.
  45     #!-gencgc
  46     (storew zr-tn pa-flag -1)
  47     (storew length vector vector-length-slot other-pointer-lowtag)
  48     (move result vector)))
  49
  50 (define-assembly-routine (allocate-vector-on-stack
  51                           (:policy :fast-safe)
  52                           (:arg-types positive-fixnum
  53                                       positive-fixnum
  54                                       positive-fixnum))
  55     ((:arg type any-reg r0-offset)
  56      (:arg length any-reg r1-offset)
  57      (:arg words any-reg r2-offset)
  58      (:res result descriptor-reg r0-offset)
  59
  60      (:temp temp non-descriptor-reg nl0-offset))
  61   (pseudo-atomic (temp)
  62     (inst lsr temp type n-fixnum-tag-bits)
  63     (inst lsl words words (- word-shift n-fixnum-tag-bits))
  64     (inst add words words (* (1+ vector-data-offset) n-word-bytes))
  65     (inst and words words (bic-mask lowtag-mask)) ; double-word align
  66     (allocation result words nil :stack-allocate-p t)
  67
  68     (inst stp temp length (@ result))
  69     ;; Zero fill
  70     (assemble ()
  71       ;; The header word has already been set, skip it.
  72       (inst add temp result (* n-word-bytes 2))
  73       (inst add words result words)
  74       LOOP
  75       (inst stp zr-tn zr-tn (@ temp (* n-word-bytes 2) :post-index))
  76       (inst cmp temp words)
  77       (inst b :lt LOOP))
  78     (inst orr result result other-pointer-lowtag)))