1 /* SPDX-License-Identifier: GPL-2.0-only */ !! 1 /* strlen.S: Sparc optimized strlen code
2 /* !! 2 * Hand optimized from GNU libc's strlen
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Sy !! 3 * Copyright (C) 1991,1996 Free Software Foundation
>> 4 * Copyright (C) 1996,2008 David S. Miller (davem@davemloft.net)
>> 5 * Copyright (C) 1996, 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
4 */ 6 */
5 7
6 #include <linux/linkage.h> 8 #include <linux/linkage.h>
>> 9 #include <asm/asm.h>
>> 10 #include <asm/export.h>
7 11
8 ENTRY_CFI(strlen) !! 12 #define LO_MAGIC 0x01010101
9 or r3,r0,7 !! 13 #define HI_MAGIC 0x80808080
10 ld r2,[r3,-7] <<
11 ld.a r6,[r3,-3] <<
12 mov r4,0x01010101 <<
13 ; uses long immediate <<
14 #ifdef __LITTLE_ENDIAN__ <<
15 asl_s r1,r0,3 <<
16 btst_s r0,2 <<
17 asl r7,r4,r1 <<
18 ror r5,r4 <<
19 sub r1,r2,r7 <<
20 bic_s r1,r1,r2 <<
21 mov.eq r7,r4 <<
22 sub r12,r6,r7 <<
23 bic r12,r12,r6 <<
24 or.eq r12,r12,r1 <<
25 and r12,r12,r5 <<
26 brne r12,0,.Learly_end <<
27 #else /* BIG ENDIAN */ <<
28 ror r5,r4 <<
29 btst_s r0,2 <<
30 mov_s r1,31 <<
31 sub3 r7,r1,r0 <<
32 sub r1,r2,r4 <<
33 bic_s r1,r1,r2 <<
34 bmsk r1,r1,r7 <<
35 sub r12,r6,r4 <<
36 bic r12,r12,r6 <<
37 bmsk.ne r12,r12,r7 <<
38 or.eq r12,r12,r1 <<
39 and r12,r12,r5 <<
40 brne r12,0,.Learly_end <<
41 #endif /* ENDIAN */ <<
42 14
43 .Loop: !! 15 .text
44 ld_s r2,[r3,4] !! 16 ENTRY(strlen)
45 ld.a r6,[r3,8] !! 17 mov %o0, %o1
46 ; stall for load result !! 18 andcc %o0, 3, %g0
47 sub r1,r2,r4 !! 19 BRANCH32(be, pt, 9f)
48 bic_s r1,r1,r2 !! 20 sethi %hi(HI_MAGIC), %o4
49 sub r12,r6,r4 !! 21 ldub [%o0], %o5
50 bic r12,r12,r6 !! 22 BRANCH_REG_ZERO(pn, %o5, 11f)
51 or r12,r12,r1 !! 23 add %o0, 1, %o0
52 and r12,r12,r5 !! 24 andcc %o0, 3, %g0
53 breq r12,0,.Loop !! 25 BRANCH32(be, pn, 4f)
54 .Lend: !! 26 or %o4, %lo(HI_MAGIC), %o3
55 and.f r1,r1,r5 !! 27 ldub [%o0], %o5
56 sub.ne r3,r3,4 !! 28 BRANCH_REG_ZERO(pn, %o5, 12f)
57 mov.eq r1,r12 !! 29 add %o0, 1, %o0
58 #ifdef __LITTLE_ENDIAN__ !! 30 andcc %o0, 3, %g0
59 sub_s r2,r1,1 !! 31 BRANCH32(be, pt, 5f)
60 bic_s r2,r2,r1 !! 32 sethi %hi(LO_MAGIC), %o4
61 norm r1,r2 !! 33 ldub [%o0], %o5
62 sub_s r0,r0,3 !! 34 BRANCH_REG_ZERO(pn, %o5, 13f)
63 lsr_s r1,r1,3 !! 35 add %o0, 1, %o0
64 sub r0,r3,r0 !! 36 BRANCH32(ba, pt, 8f)
65 j_s.d [blink] !! 37 or %o4, %lo(LO_MAGIC), %o2
66 sub r0,r0,r1 !! 38 9:
67 #else /* BIG ENDIAN */ !! 39 or %o4, %lo(HI_MAGIC), %o3
68 lsr_s r1,r1,7 !! 40 4:
69 mov.eq r2,r6 !! 41 sethi %hi(LO_MAGIC), %o4
70 bic_s r1,r1,r2 !! 42 5:
71 norm r1,r1 !! 43 or %o4, %lo(LO_MAGIC), %o2
72 sub r0,r3,r0 !! 44 8:
73 lsr_s r1,r1,3 !! 45 ld [%o0], %o5
74 j_s.d [blink] !! 46 2:
75 add r0,r0,r1 !! 47 sub %o5, %o2, %o4
76 #endif /* ENDIAN */ !! 48 andcc %o4, %o3, %g0
77 .Learly_end: !! 49 BRANCH32(be, pt, 8b)
78 b.d .Lend !! 50 add %o0, 4, %o0
79 sub_s.ne r1,r1,r1 !! 51
80 END_CFI(strlen) !! 52 /* Check every byte. */
>> 53 srl %o5, 24, %g7
>> 54 andcc %g7, 0xff, %g0
>> 55 BRANCH32(be, pn, 1f)
>> 56 add %o0, -4, %o4
>> 57 srl %o5, 16, %g7
>> 58 andcc %g7, 0xff, %g0
>> 59 BRANCH32(be, pn, 1f)
>> 60 add %o4, 1, %o4
>> 61 srl %o5, 8, %g7
>> 62 andcc %g7, 0xff, %g0
>> 63 BRANCH32(be, pn, 1f)
>> 64 add %o4, 1, %o4
>> 65 andcc %o5, 0xff, %g0
>> 66 BRANCH32_ANNUL(bne, pt, 2b)
>> 67 ld [%o0], %o5
>> 68 add %o4, 1, %o4
>> 69 1:
>> 70 retl
>> 71 sub %o4, %o1, %o0
>> 72 11:
>> 73 retl
>> 74 mov 0, %o0
>> 75 12:
>> 76 retl
>> 77 mov 1, %o0
>> 78 13:
>> 79 retl
>> 80 mov 2, %o0
>> 81 ENDPROC(strlen)
>> 82 EXPORT_SYMBOL(strlen)
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