arch/m32r/lib/memcpy.S

   1 /*
   2  *  linux/arch/m32r/lib/memcpy.S
   3  *
   4  *  Copyright (C) 2001  Hiroyuki Kondo, and Hirokazu Takata
   5  *  Copyright (C) 2004  Hirokazu Takata
   6  *
   7  *  void *memcopy(void *dst, const void *src, int n);
   8  *
   9  *        dst: r0
  10  *        src: r1
  11  *        n  : r2
  12  */
  13
  14         .text
  15 #include <linux/linkage.h>
  16 #include <asm/assembler.h>
  17
  18 #ifdef CONFIG_ISA_DUAL_ISSUE
  19
  20         .text
  21 ENTRY(memcpy)
  22 memcopy:
  23         mv      r4, r0              ||  mv      r7, r0
  24         or      r7, r1              ||  cmpz    r2
  25         jc      r14                 ||  cmpeq   r0, r1  ; return if r2=0
  26         jc      r14                                     ; return if r0=r1
  27
  28         and3    r7, r7, #3
  29         bnez    r7, byte_copy
  30         srl3    r3, r2, #2
  31         and3    r2, r2, #3
  32         beqz    r3, byte_copy
  33         addi    r4, #-4
  34 word_copy:
  35         ld      r7, @r1+            ||  addi    r3, #-1
  36         st      r7, @+r4            ||  cmpz    r2
  37         bnez    r3, word_copy
  38         addi    r4, #4              ||  jc      r14     ; return if r2=0
  39 #if defined(CONFIG_ISA_M32R2)
  40 byte_copy:
  41         ldb     r7, @r1             ||  addi    r1, #1
  42         addi    r2, #-1             ||  stb     r7, @r4+
  43         bnez    r2, byte_copy
  44 #elif defined(CONFIG_ISA_M32R)
  45 byte_copy:
  46         ldb     r7, @r1             ||  addi    r1, #1
  47         addi    r2, #-1             ||  stb     r7, @r4
  48         addi    r4, #1
  49         bnez    r2, byte_copy
  50 #else
  51 #error unknown isa configuration
  52 #endif
  53 end_memcopy:
  54         jmp     r14
  55
  56 #else /* not CONFIG_ISA_DUAL_ISSUE */
  57
  58         .text
  59 ENTRY(memcpy)
  60 memcopy:
  61         mv      r4, r0
  62         mv      r7, r0
  63         or      r7, r1
  64         beq     r0, r1, end_memcopy
  65         beqz    r2, end_memcopy
  66
  67         and3    r7, r7, #3
  68         bnez    r7, byte_copy
  69         srl3    r3, r2, #2
  70         and3    r2, r2, #3
  71         beqz    r3, byte_copy
  72         addi    r4, #-4
  73 word_copy:
  74         ld      r7, @r1+
  75         addi    r3, #-1
  76         st      r7, @+r4
  77         bnez    r3, word_copy
  78         beqz    r2, end_memcopy
  79         addi    r4, #4
  80 byte_copy:
  81         ldb     r7, @r1
  82         addi    r1, #1
  83         addi    r2, #-1
  84         stb     r7, @r4
  85         addi    r4, #1
  86         bnez    r2, byte_copy
  87 end_memcopy:
  88         jmp     r14
  89
  90 #endif /* not CONFIG_ISA_DUAL_ISSUE */
  91
  92         .end