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Diffstat (limited to 'arch/arc/lib/strcpy-700.S')
| -rw-r--r-- | arch/arc/lib/strcpy-700.S | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/arc/lib/strcpy-700.S b/arch/arc/lib/strcpy-700.S new file mode 100644 index 000000000000..b7ca4ae81d88 --- /dev/null +++ b/arch/arc/lib/strcpy-700.S | |||
| @@ -0,0 +1,70 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) | ||
| 3 | * | ||
| 4 | * This program is free software; you can redistribute it and/or modify | ||
| 5 | * it under the terms of the GNU General Public License version 2 as | ||
| 6 | * published by the Free Software Foundation. | ||
| 7 | */ | ||
| 8 | |||
| 9 | /* If dst and src are 4 byte aligned, copy 8 bytes at a time. | ||
| 10 | If the src is 4, but not 8 byte aligned, we first read 4 bytes to get | ||
| 11 | it 8 byte aligned. Thus, we can do a little read-ahead, without | ||
| 12 | dereferencing a cache line that we should not touch. | ||
| 13 | Note that short and long instructions have been scheduled to avoid | ||
| 14 | branch stalls. | ||
| 15 | The beq_s to r3z could be made unaligned & long to avoid a stall | ||
| 16 | there, but the it is not likely to be taken often, and it | ||
| 17 | would also be likey to cost an unaligned mispredict at the next call. */ | ||
| 18 | |||
| 19 | #include <asm/linkage.h> | ||
| 20 | |||
| 21 | ARC_ENTRY strcpy | ||
| 22 | or r2,r0,r1 | ||
| 23 | bmsk_s r2,r2,1 | ||
| 24 | brne.d r2,0,charloop | ||
| 25 | mov_s r10,r0 | ||
| 26 | ld_s r3,[r1,0] | ||
| 27 | mov r8,0x01010101 | ||
| 28 | bbit0.d r1,2,loop_start | ||
| 29 | ror r12,r8 | ||
| 30 | sub r2,r3,r8 | ||
| 31 | bic_s r2,r2,r3 | ||
| 32 | tst_s r2,r12 | ||
| 33 | bne r3z | ||
| 34 | mov_s r4,r3 | ||
| 35 | .balign 4 | ||
| 36 | loop: | ||
| 37 | ld.a r3,[r1,4] | ||
| 38 | st.ab r4,[r10,4] | ||
| 39 | loop_start: | ||
| 40 | ld.a r4,[r1,4] | ||
| 41 | sub r2,r3,r8 | ||
| 42 | bic_s r2,r2,r3 | ||
| 43 | tst_s r2,r12 | ||
| 44 | bne_s r3z | ||
| 45 | st.ab r3,[r10,4] | ||
| 46 | sub r2,r4,r8 | ||
| 47 | bic r2,r2,r4 | ||
| 48 | tst r2,r12 | ||
| 49 | beq loop | ||
| 50 | mov_s r3,r4 | ||
| 51 | #ifdef __LITTLE_ENDIAN__ | ||
| 52 | r3z: bmsk.f r1,r3,7 | ||
| 53 | lsr_s r3,r3,8 | ||
| 54 | #else | ||
| 55 | r3z: lsr.f r1,r3,24 | ||
| 56 | asl_s r3,r3,8 | ||
| 57 | #endif | ||
| 58 | bne.d r3z | ||
| 59 | stb.ab r1,[r10,1] | ||
| 60 | j_s [blink] | ||
| 61 | |||
| 62 | .balign 4 | ||
| 63 | charloop: | ||
| 64 | ldb.ab r3,[r1,1] | ||
| 65 | |||
| 66 | |||
| 67 | brne.d r3,0,charloop | ||
| 68 | stb.ab r3,[r10,1] | ||
| 69 | j [blink] | ||
| 70 | ARC_EXIT strcpy | ||