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| /* SPDX-License-Identifier: GPL-2.0-only */
| /*
| * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
| */
|
| /* ARC700 has a relatively long pipeline and branch prediction, so we want
| to avoid branches that are hard to predict. On the other hand, the
| presence of the norm instruction makes it easier to operate on whole
| words branch-free. */
|
| #include <linux/linkage.h>
|
| ENTRY_CFI(strchr)
| extb_s r1,r1
| asl r5,r1,8
| bmsk r2,r0,1
| or r5,r5,r1
| mov_s r3,0x01010101
| breq.d r2,r0,.Laligned
| asl r4,r5,16
| sub_s r0,r0,r2
| asl r7,r2,3
| ld_s r2,[r0]
| #ifdef __LITTLE_ENDIAN__
| asl r7,r3,r7
| #else
| lsr r7,r3,r7
| #endif
| or r5,r5,r4
| ror r4,r3
| sub r12,r2,r7
| bic_s r12,r12,r2
| and r12,r12,r4
| brne.d r12,0,.Lfound0_ua
| xor r6,r2,r5
| ld.a r2,[r0,4]
| sub r12,r6,r7
| bic r12,r12,r6
| #ifdef __LITTLE_ENDIAN__
| and r7,r12,r4
| breq r7,0,.Loop ; For speed, we want this branch to be unaligned.
| b .Lfound_char ; Likewise this one.
| #else
| and r12,r12,r4
| breq r12,0,.Loop ; For speed, we want this branch to be unaligned.
| lsr_s r12,r12,7
| bic r2,r7,r6
| b.d .Lfound_char_b
| and_s r2,r2,r12
| #endif
| ; /* We require this code address to be unaligned for speed... */
| .Laligned:
| ld_s r2,[r0]
| or r5,r5,r4
| ror r4,r3
| ; /* ... so that this code address is aligned, for itself and ... */
| .Loop:
| sub r12,r2,r3
| bic_s r12,r12,r2
| and r12,r12,r4
| brne.d r12,0,.Lfound0
| xor r6,r2,r5
| ld.a r2,[r0,4]
| sub r12,r6,r3
| bic r12,r12,r6
| and r7,r12,r4
| breq r7,0,.Loop /* ... so that this branch is unaligned. */
| ; Found searched-for character. r0 has already advanced to next word.
| #ifdef __LITTLE_ENDIAN__
| /* We only need the information about the first matching byte
| (i.e. the least significant matching byte) to be exact,
| hence there is no problem with carry effects. */
| .Lfound_char:
| sub r3,r7,1
| bic r3,r3,r7
| norm r2,r3
| sub_s r0,r0,1
| asr_s r2,r2,3
| j.d [blink]
| sub_s r0,r0,r2
|
| .balign 4
| .Lfound0_ua:
| mov r3,r7
| .Lfound0:
| sub r3,r6,r3
| bic r3,r3,r6
| and r2,r3,r4
| or_s r12,r12,r2
| sub_s r3,r12,1
| bic_s r3,r3,r12
| norm r3,r3
| add_s r0,r0,3
| asr_s r12,r3,3
| asl.f 0,r2,r3
| sub_s r0,r0,r12
| j_s.d [blink]
| mov.pl r0,0
| #else /* BIG ENDIAN */
| .Lfound_char:
| lsr r7,r7,7
|
| bic r2,r7,r6
| .Lfound_char_b:
| norm r2,r2
| sub_s r0,r0,4
| asr_s r2,r2,3
| j.d [blink]
| add_s r0,r0,r2
|
| .Lfound0_ua:
| mov_s r3,r7
| .Lfound0:
| asl_s r2,r2,7
| or r7,r6,r4
| bic_s r12,r12,r2
| sub r2,r7,r3
| or r2,r2,r6
| bic r12,r2,r12
| bic.f r3,r4,r12
| norm r3,r3
|
| add.pl r3,r3,1
| asr_s r12,r3,3
| asl.f 0,r2,r3
| add_s r0,r0,r12
| j_s.d [blink]
| mov.mi r0,0
| #endif /* ENDIAN */
| END_CFI(strchr)
|
|
