| Thomas Gleixner | d2912cb | 2019-06-04 10:11:33 +0200 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| Vineet Gupta | 5210d1e | 2013-01-18 15:12:18 +0530 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) |
| Vineet Gupta | 5210d1e | 2013-01-18 15:12:18 +0530 | [diff] [blame] | 4 | */ |
| 5 | |
| 6 | /* If dst and src are 4 byte aligned, copy 8 bytes at a time. |
| 7 | If the src is 4, but not 8 byte aligned, we first read 4 bytes to get |
| 8 | it 8 byte aligned. Thus, we can do a little read-ahead, without |
| 9 | dereferencing a cache line that we should not touch. |
| 10 | Note that short and long instructions have been scheduled to avoid |
| 11 | branch stalls. |
| 12 | The beq_s to r3z could be made unaligned & long to avoid a stall |
| 13 | there, but the it is not likely to be taken often, and it |
| 14 | would also be likey to cost an unaligned mispredict at the next call. */ |
| 15 | |
| Vineet Gupta | ec7ac6a | 2014-02-07 13:47:43 +0530 | [diff] [blame] | 16 | #include <linux/linkage.h> |
| Vineet Gupta | 5210d1e | 2013-01-18 15:12:18 +0530 | [diff] [blame] | 17 | |
| Vineet Gupta | 86effd0 | 2016-09-19 16:42:25 -0700 | [diff] [blame] | 18 | ENTRY_CFI(strcpy) |
| Vineet Gupta | 5210d1e | 2013-01-18 15:12:18 +0530 | [diff] [blame] | 19 | or r2,r0,r1 |
| 20 | bmsk_s r2,r2,1 |
| 21 | brne.d r2,0,charloop |
| 22 | mov_s r10,r0 |
| 23 | ld_s r3,[r1,0] |
| 24 | mov r8,0x01010101 |
| 25 | bbit0.d r1,2,loop_start |
| 26 | ror r12,r8 |
| 27 | sub r2,r3,r8 |
| 28 | bic_s r2,r2,r3 |
| 29 | tst_s r2,r12 |
| 30 | bne r3z |
| 31 | mov_s r4,r3 |
| 32 | .balign 4 |
| 33 | loop: |
| 34 | ld.a r3,[r1,4] |
| 35 | st.ab r4,[r10,4] |
| 36 | loop_start: |
| 37 | ld.a r4,[r1,4] |
| 38 | sub r2,r3,r8 |
| 39 | bic_s r2,r2,r3 |
| 40 | tst_s r2,r12 |
| 41 | bne_s r3z |
| 42 | st.ab r3,[r10,4] |
| 43 | sub r2,r4,r8 |
| 44 | bic r2,r2,r4 |
| 45 | tst r2,r12 |
| 46 | beq loop |
| 47 | mov_s r3,r4 |
| 48 | #ifdef __LITTLE_ENDIAN__ |
| 49 | r3z: bmsk.f r1,r3,7 |
| 50 | lsr_s r3,r3,8 |
| 51 | #else |
| 52 | r3z: lsr.f r1,r3,24 |
| 53 | asl_s r3,r3,8 |
| 54 | #endif |
| 55 | bne.d r3z |
| 56 | stb.ab r1,[r10,1] |
| 57 | j_s [blink] |
| 58 | |
| 59 | .balign 4 |
| 60 | charloop: |
| 61 | ldb.ab r3,[r1,1] |
| 62 | |
| 63 | |
| 64 | brne.d r3,0,charloop |
| 65 | stb.ab r3,[r10,1] |
| 66 | j [blink] |
| Vineet Gupta | 86effd0 | 2016-09-19 16:42:25 -0700 | [diff] [blame] | 67 | END_CFI(strcpy) |