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memmove.S

memmove.S 2.1 KB
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  1. /* SPDX-License-Identifier: GPL-2.0 */
    2. 

  2. // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
    3. 

  3. 

  4. #include <linux/linkage.h>
    5. 

  5. #include "sysdep.h"
    6. 

  6. 

  7. 	.weak memmove
    8. 

  8. ENTRY(__memmove)
    9. 

  9. ENTRY(memmove)
    10. 

  10. 	subu	r3, r0, r1
    11. 

  11. 	cmphs	r3, r2
    12. 

  12. 	bt	memcpy
    13. 

  13. 

  14. 	mov	r12, r0
    15. 

  15. 	addu	r0, r0, r2
    16. 

  16. 	addu	r1, r1, r2
    17. 

  17. 

  18. 	/* Test if len less than 4 bytes.  */
    19. 

  19. 	cmplti	r2, 4
    20. 

  20. 	bt	.L_copy_by_byte
    21. 

  21. 

  22. 	andi	r13, r0, 3
    23. 

  23. 	/* Test if dest is not 4 bytes aligned.  */
    24. 

  24. 	bnez	r13, .L_dest_not_aligned
    25. 

  25. 	/* Hardware can handle unaligned access directly.  */
    26. 

  26. .L_dest_aligned:
    27. 

  27. 	/* If dest is aligned, then copy.  */
    28. 

  28. 	zext	r18, r2, 31, 4
    29. 

  29. 	/* Test if len less than 16 bytes.  */
    30. 

  30. 	bez	r18, .L_len_less_16bytes
    31. 

  31. 	movi	r19, 0
    32. 

  32. 

  33. 	/* len > 16 bytes */
    34. 

  34. 	LABLE_ALIGN
    35. 

  35. .L_len_larger_16bytes:
    36. 

  36. 	subi	r1, 16
    37. 

  37. 	subi	r0, 16
    38. 

  38. #if defined(__CSKY_VDSPV2__)
    39. 

  39. 	vldx.8	vr0, (r1), r19
    40. 

  40. 	PRE_BNEZAD (r18)
    41. 

  41. 	vstx.8	vr0, (r0), r19
    42. 

  42. #elif defined(__CK860__)
    43. 

  43. 	ldw	r3, (r1, 12)
    44. 

  44. 	stw	r3, (r0, 12)
    45. 

  45. 	ldw	r3, (r1, 8)
    46. 

  46. 	stw	r3, (r0, 8)
    47. 

  47. 	ldw	r3, (r1, 4)
    48. 

  48. 	stw	r3, (r0, 4)
    49. 

  49. 	ldw	r3, (r1, 0)
    50. 

  50. 	stw	r3, (r0, 0)
    51. 

  51. #else
    52. 

  52. 	ldw	r20, (r1, 0)
    53. 

  53. 	ldw	r21, (r1, 4)
    54. 

  54. 	ldw	r22, (r1, 8)
    55. 

  55. 	ldw	r23, (r1, 12)
    56. 

  56. 	stw	r20, (r0, 0)
    57. 

  57. 	stw	r21, (r0, 4)
    58. 

  58. 	stw	r22, (r0, 8)
    59. 

  59. 	stw	r23, (r0, 12)
    60. 

  60. 	PRE_BNEZAD (r18)
    61. 

  61. #endif
    62. 

  62. 	BNEZAD (r18, .L_len_larger_16bytes)
    63. 

  63. 

  64. .L_len_less_16bytes:
    65. 

  65. 	zext	r18, r2, 3, 2
    66. 

  66. 	bez	r18, .L_copy_by_byte
    67. 

  67. .L_len_less_16bytes_loop:
    68. 

  68. 	subi	r1, 4
    69. 

  69. 	subi	r0, 4
    70. 

  70. 	ldw	r3, (r1, 0)
    71. 

  71. 	PRE_BNEZAD (r18)
    72. 

  72. 	stw	r3, (r0, 0)
    73. 

  73. 	BNEZAD (r18, .L_len_less_16bytes_loop)
    74. 

  74. 

  75. 	/* Test if len less than 4 bytes.  */
    76. 

  76. .L_copy_by_byte:
    77. 

  77. 	zext	r18, r2, 1, 0
    78. 

  78. 	bez	r18, .L_return
    79. 

  79. .L_copy_by_byte_loop:
    80. 

  80. 	subi	r1, 1
    81. 

  81. 	subi	r0, 1
    82. 

  82. 	ldb	r3, (r1, 0)
    83. 

  83. 	PRE_BNEZAD (r18)
    84. 

  84. 	stb	r3, (r0, 0)
    85. 

  85. 	BNEZAD (r18, .L_copy_by_byte_loop)
    86. 

  86. 

  87. .L_return:
    88. 

  88. 	mov	r0, r12
    89. 

  89. 	rts
    90. 

  90. 

  91. 	/* If dest is not aligned, just copy some bytes makes the dest
    92. 

  92. 	   align.  */
    93. 

  93. .L_dest_not_aligned:
    94. 

  94. 	sub	r2, r13
    95. 

  95. .L_dest_not_aligned_loop:
    96. 

  96. 	subi	r1, 1
    97. 

  97. 	subi	r0, 1
    98. 

  98. 	/* Makes the dest align.  */
    99. 

  99. 	ldb	r3, (r1, 0)
    100. 

  100. 	PRE_BNEZAD (r13)
    101. 

  101. 	stb	r3, (r0, 0)
    102. 

  102. 	BNEZAD (r13, .L_dest_not_aligned_loop)
    103. 

  103. 	cmplti	r2, 4
    104. 

  104. 	bt	.L_copy_by_byte
    105. 

  105. 	/* Check whether the src is aligned.  */
    106. 

  106. 	jbr	.L_dest_aligned
    107. 

  107. ENDPROC(memmove)
    108. 

  108. ENDPROC(__memmove)
    109.