arch/h8300/lib/memset.S

   1 /* memset.S */
   2
   3 #include <asm/linkage.h>
   4
   5 #if defined(CONFIG_CPU_H8300H)
   6         .h8300h
   7 #endif
   8 #if defined(CONFIG_CPU_H8S)
   9         .h8300s
  10 #endif
  11         .text
  12
  13 .global memset
  14 .global clear_user
  15
  16 ;;void *memset(*ptr, int c, size_t count)
  17 ;; ptr = er0
  18 ;; c   = er1(r1l)
  19 ;; count = er2
  20 memset:
  21         btst    #0,r0l
  22         beq     2f
  23
  24         ;; odd address
  25 1:
  26         mov.b   r1l,@er0
  27         adds    #1,er0
  28         dec.l   #1,er2
  29         beq     6f
  30
  31         ;; even address
  32 2:
  33         mov.l   er2,er3
  34         cmp.l   #4,er2
  35         blo     4f
  36         ;; count>=4 -> count/4
  37 #if defined(CONFIG_CPU_H8300H)
  38         shlr.l  er2
  39         shlr.l  er2
  40 #endif
  41 #if defined(CONFIG_CPU_H8S)
  42         shlr.l  #2,er2
  43 #endif
  44         ;; byte -> long
  45         mov.b   r1l,r1h
  46         mov.w   r1,e1
  47 3:
  48         mov.l   er1,@er0
  49         adds    #4,er0
  50         dec.l   #1,er2
  51         bne     3b
  52 4:
  53         ;; count % 4
  54         and.b   #3,r3l
  55         beq     6f
  56 5:
  57         mov.b   r1l,@er0
  58         adds    #1,er0
  59         dec.b   r3l
  60         bne     5b
  61 6:
  62         rts
  63
  64 clear_user:
  65         mov.l   er1, er2
  66         sub.l   er1, er1
  67         bra     memset
  68
  69         .end