Warning: That file was not part of the compilation database. It may have many parsing errors.

1/* Copyright (C) 1996-2019 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library. If not, see
16 <http://www.gnu.org/licenses/>. */
17
18/* Return the address of the last occurrence of a given character
19 within a null-terminated string, or null if it is not found.
20
21 This is generally scheduled for the EV5 (got to look out for my own
22 interests :-), but with EV4 needs in mind. There are, in fact, fewer
23 stalls on the EV4 than there are on the EV5.
24*/
25
26#include <sysdep.h>
27
28 .set noreorder
29 .set noat
30
31ENTRY(strrchr)
32#ifdef PROF
33 ldgp gp, 0(pv)
34 lda AT, _mcount
35 jsr AT, (AT), _mcount
36 .prologue 1
37#else
38 .prologue 0
39#endif
40
41 and a1, 0xff, a1 # e0 : zero extend our test character
42 mov zero, t6 # .. e1 : t6 is last match aligned addr
43 sll a1, 8, t5 # e0 : replicate our test character
44 mov zero, t7 # .. e1 : t7 is last match byte compare mask
45 or t5, a1, a1 # e0 :
46 ldq_u t0, 0(a0) # .. e1 : load first quadword
47 sll a1, 16, t5 # e0 :
48 andnot a0, 7, v0 # .. e1 : align source addr
49 or t5, a1, a1 # e0 :
50 lda t4, -1 # .. e1 : build garbage mask
51 sll a1, 32, t5 # e0 :
52 cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero
53 mskqh t4, a0, t4 # e0 :
54 or t5, a1, a1 # .. e1 : character replication complete
55 xor t0, a1, t2 # e0 : make bytes == c zero
56 cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage
57 cmpbge zero, t2, t3 # e0 : bits set iff byte == c
58 andnot t1, t4, t1 # .. e1 : clear garbage from null test
59 andnot t3, t4, t3 # e0 : clear garbage from char test
60 bne t1, $eos # .. e1 : did we already hit the terminator?
61
62 /* Character search main loop */
63$loop:
64 ldq t0, 8(v0) # e0 : load next quadword
65 cmovne t3, v0, t6 # .. e1 : save previous comparisons match
66 cmovne t3, t3, t7 # e0 :
67 addq v0, 8, v0 # .. e1 :
68 xor t0, a1, t2 # e0 :
69 cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero
70 cmpbge zero, t2, t3 # e0 : bits set iff byte == c
71 beq t1, $loop # .. e1 : if we havnt seen a null, loop
72
73 /* Mask out character matches after terminator */
74$eos:
75 negq t1, t4 # e0 : isolate first null byte match
76 and t1, t4, t4 # e1 :
77 subq t4, 1, t5 # e0 : build a mask of the bytes upto...
78 or t4, t5, t4 # e1 : ... and including the null
79
80 and t3, t4, t3 # e0 : mask out char matches after null
81 cmovne t3, t3, t7 # .. e1 : save it, if match found
82 cmovne t3, v0, t6 # e0 :
83
84 /* Locate the address of the last matched character */
85
86 /* Retain the early exit for the ev4 -- the ev5 mispredict penalty
87 is 5 cycles -- the same as just falling through. */
88 beq t7, $retnull # .. e1 :
89
90 and t7, 0xf0, t2 # e0 : binary search for the high bit set
91 cmovne t2, t2, t7 # .. e1 (zdb)
92 cmovne t2, 4, t2 # e0 :
93 and t7, 0xcc, t1 # .. e1 :
94 cmovne t1, t1, t7 # e0 :
95 cmovne t1, 2, t1 # .. e1 :
96 and t7, 0xaa, t0 # e0 :
97 cmovne t0, 1, t0 # .. e1 (zdb)
98 addq t2, t1, t1 # e0 :
99 addq t6, t0, v0 # .. e1 : add our aligned base ptr to the mix
100 addq v0, t1, v0 # e0 :
101 ret # .. e1 :
102
103$retnull:
104 mov zero, v0 # e0 :
105 ret # .. e1 :
106
107 END(strrchr)
108
109weak_alias (strrchr, rindex)
110libc_hidden_builtin_def (strrchr)
111

Warning: That file was not part of the compilation database. It may have many parsing errors.