| 1 | /* SPDX-License-Identifier: GPL-2.0 */
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| 2 | /* $Id: memset.S,v 1.1 2000/04/14 16:49:01 mjd Exp $
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| 3 | *
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| 4 | * "memset" implementation of SuperH
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| 5 | *
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| 6 | * Copyright (C) 1999 Niibe Yutaka
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| 7 | *
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| 8 | */
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| 9 |
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| 10 | /*
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| 11 | * void *memset(void *s, int c, size_t n);
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| 12 | */
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| 13 |
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| 14 | |
| 15 |
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| 16 | ENTRY(memset)
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| 17 | tst r6,r6
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| 18 | bt/s 5f ! if n=0, do nothing
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| 19 | add r6,r4
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| 20 | mov |
| 21 | cmp/gt r6,r0
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| 22 | bt/s 4f ! if it's too small, set a byte at once
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| 23 | mov r4,r0
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| 24 | and #3,r0
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| 25 | cmp/eq #0,r0
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| 26 | bt/s 2f ! It's aligned
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| 27 | sub r0,r6
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| 28 | 1:
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| 29 | dt r0
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| 30 | bf/s 1b
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| 31 | mov.b r5,@-r4
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| 32 | 2: ! make VVVV
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| 33 | extu.b r5,r5
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| 34 | swap.b r5,r0 ! V0
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| 35 | or r0,r5 ! VV
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| 36 | swap.w r5,r0 ! VV00
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| 37 | or r0,r5 ! VVVV
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| 38 | !
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| 39 | mov r6,r0
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| 40 | shlr2 r0
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| 41 | shlr r0 ! r0 = r6 >> 3
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| 42 | 3:
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| 43 | dt r0
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| 44 | mov.l r5,@-r4 ! set 8-byte at once
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| 45 | bf/s 3b
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| 46 | mov.l r5,@-r4
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| 47 | !
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| 48 | mov |
| 49 | and r0,r6
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| 50 | tst r6,r6
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| 51 | bt 5f
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| 52 | ! fill bytes
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| 53 | 4:
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| 54 | dt r6
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| 55 | bf/s 4b
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| 56 | mov.b r5,@-r4
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| 57 | 5:
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| 58 | rts
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| 59 | mov r4,r0
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