arch/arc/lib/memset-archs.S

   1 /*
   2  * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/linkage.h>
  10
  11 #undef PREALLOC_NOT_AVAIL
  12
  13 ENTRY_CFI(memset)
  14         prefetchw [r0]          ; Prefetch the write location
  15         mov.f   0, r2
  16 ;;; if size is zero
  17         jz.d    [blink]
  18         mov     r3, r0          ; don't clobber ret val
  19
  20 ;;; if length < 8
  21         brls.d.nt       r2, 8, .Lsmallchunk
  22         mov.f   lp_count,r2
  23
  24         and.f   r4, r0, 0x03
  25         rsub    lp_count, r4, 4
  26         lpnz    @.Laligndestination
  27         ;; LOOP BEGIN
  28         stb.ab  r1, [r3,1]
  29         sub     r2, r2, 1
  30 .Laligndestination:
  31
  32 ;;; Destination is aligned
  33         and     r1, r1, 0xFF
  34         asl     r4, r1, 8
  35         or      r4, r4, r1
  36         asl     r5, r4, 16
  37         or      r5, r5, r4
  38         mov     r4, r5
  39
  40         sub3    lp_count, r2, 8
  41         cmp     r2, 64
  42         bmsk.hi r2, r2, 5
  43         mov.ls  lp_count, 0
  44         add3.hi r2, r2, 8
  45
  46 ;;; Convert len to Dwords, unfold x8
  47         lsr.f   lp_count, lp_count, 6
  48
  49         lpnz    @.Lset64bytes
  50         ;; LOOP START
  51 #ifdef PREALLOC_NOT_AVAIL
  52         prefetchw [r3, 64]      ;Prefetch the next write location
  53 #else
  54         prealloc  [r3, 64]
  55 #endif
  56 #ifdef CONFIG_ARC_HAS_LL64
  57         std.ab  r4, [r3, 8]
  58         std.ab  r4, [r3, 8]
  59         std.ab  r4, [r3, 8]
  60         std.ab  r4, [r3, 8]
  61         std.ab  r4, [r3, 8]
  62         std.ab  r4, [r3, 8]
  63         std.ab  r4, [r3, 8]
  64         std.ab  r4, [r3, 8]
  65 #else
  66         st.ab   r4, [r3, 4]
  67         st.ab   r4, [r3, 4]
  68         st.ab   r4, [r3, 4]
  69         st.ab   r4, [r3, 4]
  70         st.ab   r4, [r3, 4]
  71         st.ab   r4, [r3, 4]
  72         st.ab   r4, [r3, 4]
  73         st.ab   r4, [r3, 4]
  74         st.ab   r4, [r3, 4]
  75         st.ab   r4, [r3, 4]
  76         st.ab   r4, [r3, 4]
  77         st.ab   r4, [r3, 4]
  78         st.ab   r4, [r3, 4]
  79         st.ab   r4, [r3, 4]
  80         st.ab   r4, [r3, 4]
  81         st.ab   r4, [r3, 4]
  82 #endif
  83 .Lset64bytes:
  84
  85         lsr.f   lp_count, r2, 5 ;Last remaining  max 124 bytes
  86         lpnz    .Lset32bytes
  87         ;; LOOP START
  88         prefetchw   [r3, 32]    ;Prefetch the next write location
  89 #ifdef CONFIG_ARC_HAS_LL64
  90         std.ab  r4, [r3, 8]
  91         std.ab  r4, [r3, 8]
  92         std.ab  r4, [r3, 8]
  93         std.ab  r4, [r3, 8]
  94 #else
  95         st.ab   r4, [r3, 4]
  96         st.ab   r4, [r3, 4]
  97         st.ab   r4, [r3, 4]
  98         st.ab   r4, [r3, 4]
  99         st.ab   r4, [r3, 4]
 100         st.ab   r4, [r3, 4]
 101         st.ab   r4, [r3, 4]
 102         st.ab   r4, [r3, 4]
 103 #endif
 104 .Lset32bytes:
 105
 106         and.f   lp_count, r2, 0x1F ;Last remaining 31 bytes
 107 .Lsmallchunk:
 108         lpnz    .Lcopy3bytes
 109         ;; LOOP START
 110         stb.ab  r1, [r3, 1]
 111 .Lcopy3bytes:
 112
 113         j       [blink]
 114
 115 END_CFI(memset)
 116
 117 ENTRY_CFI(memzero)
 118     ; adjust bzero args to memset args
 119     mov r2, r1
 120     b.d  memset    ;tail call so need to tinker with blink
 121     mov r1, 0
 122 END_CFI(memzero)