1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
|
/* Optimized strcmp implementation for PowerPC32.
Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
/* int [r3] memcmp (const char *s1 [r3],
const char *s2 [r4],
size_t size [r5]) */
.machine power4
EALIGN (memcmp, 4, 0)
CALL_MCOUNT
#define rRTN r3
#define rSTR1 r3 /* first string arg */
#define rSTR2 r4 /* second string arg */
#define rN r5 /* max string length */
#define rWORD1 r6 /* current word in s1 */
#define rWORD2 r7 /* current word in s2 */
#define rWORD3 r8 /* next word in s1 */
#define rWORD4 r9 /* next word in s2 */
#define rWORD5 r10 /* next word in s1 */
#define rWORD6 r11 /* next word in s2 */
#define rWORD7 r30 /* next word in s1 */
#define rWORD8 r31 /* next word in s2 */
xor r0, rSTR2, rSTR1
cmplwi cr6, rN, 0
cmplwi cr1, rN, 12
clrlwi. r0, r0, 30
clrlwi r12, rSTR1, 30
cmplwi cr5, r12, 0
beq- cr6, L(zeroLength)
dcbt 0, rSTR1
dcbt 0, rSTR2
/* If less than 8 bytes or not aligned, use the unaligned
byte loop. */
blt cr1, L(bytealigned)
stwu 1, -64(r1)
cfi_adjust_cfa_offset(64)
stw rWORD8, 48(r1)
cfi_offset(rWORD8, (48-64))
stw rWORD7, 44(r1)
cfi_offset(rWORD7, (44-64))
bne L(unaligned)
/* At this point we know both strings have the same alignment and the
compare length is at least 8 bytes. r12 contains the low order
2 bits of rSTR1 and cr5 contains the result of the logical compare
of r12 to 0. If r12 == 0 then we are already word
aligned and can perform the word aligned loop.
Otherwise we know the two strings have the same alignment (but not
yet word aligned). So we force the string addresses to the next lower
word boundary and special case this first word using shift left to
eliminate bits preceding the first byte. Since we want to join the
normal (word aligned) compare loop, starting at the second word,
we need to adjust the length (rN) and special case the loop
versioning for the first word. This ensures that the loop count is
correct and the first word (shifted) is in the expected register pair. */
.align 4
L(samealignment):
clrrwi rSTR1, rSTR1, 2
clrrwi rSTR2, rSTR2, 2
beq cr5, L(Waligned)
add rN, rN, r12
slwi rWORD6, r12, 3
srwi r0, rN, 4 /* Divide by 16 */
andi. r12, rN, 12 /* Get the word remainder */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 0(rSTR1)
lwz rWORD2, 0(rSTR2)
#endif
cmplwi cr1, r12, 8
cmplwi cr7, rN, 16
clrlwi rN, rN, 30
beq L(dPs4)
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
bgt cr1, L(dPs3)
beq cr1, L(dPs2)
/* Remainder is 4 */
.align 3
L(dsP1):
slw rWORD5, rWORD1, rWORD6
slw rWORD6, rWORD2, rWORD6
cmplw cr5, rWORD5, rWORD6
blt cr7, L(dP1x)
/* Do something useful in this cycle since we have to branch anyway. */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
b L(dP1e)
/* Remainder is 8 */
.align 4
L(dPs2):
slw rWORD5, rWORD1, rWORD6
slw rWORD6, rWORD2, rWORD6
cmplw cr6, rWORD5, rWORD6
blt cr7, L(dP2x)
/* Do something useful in this cycle since we have to branch anyway. */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD7, 4(rSTR1)
lwz rWORD8, 4(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
b L(dP2e)
/* Remainder is 12 */
.align 4
L(dPs3):
slw rWORD3, rWORD1, rWORD6
slw rWORD4, rWORD2, rWORD6
cmplw cr1, rWORD3, rWORD4
b L(dP3e)
/* Count is a multiple of 16, remainder is 0 */
.align 4
L(dPs4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
slw rWORD1, rWORD1, rWORD6
slw rWORD2, rWORD2, rWORD6
cmplw cr7, rWORD1, rWORD2
b L(dP4e)
/* At this point we know both strings are word aligned and the
compare length is at least 8 bytes. */
.align 4
L(Waligned):
andi. r12, rN, 12 /* Get the word remainder */
srwi r0, rN, 4 /* Divide by 16 */
cmplwi cr1, r12, 8
cmplwi cr7, rN, 16
clrlwi rN, rN, 30
beq L(dP4)
bgt cr1, L(dP3)
beq cr1, L(dP2)
/* Remainder is 4 */
.align 4
L(dP1):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
/* Normally we'd use rWORD7/rWORD8 here, but since we might exit early
(8-15 byte compare), we want to use only volatile registers. This
means we can avoid restoring non-volatile registers since we did not
change any on the early exit path. The key here is the non-early
exit path only cares about the condition code (cr5), not about which
register pair was used. */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 0(rSTR1)
lwz rWORD6, 0(rSTR2)
#endif
cmplw cr5, rWORD5, rWORD6
blt cr7, L(dP1x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
L(dP1e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 8(rSTR1)
lwz rWORD4, 8(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 12(rSTR1)
lwz rWORD6, 12(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
bne cr5, L(dLcr5x)
bne cr7, L(dLcr7x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwzu rWORD7, 16(rSTR1)
lwzu rWORD8, 16(rSTR2)
#endif
bne cr1, L(dLcr1)
cmplw cr5, rWORD7, rWORD8
bdnz L(dLoop)
bne cr6, L(dLcr6)
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
.align 3
L(dP1x):
slwi. r12, rN, 3
bne cr5, L(dLcr5x)
subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bne L(d00)
li rRTN, 0
blr
/* Remainder is 8 */
.align 4
cfi_adjust_cfa_offset(64)
L(dP2):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 0(rSTR1)
lwz rWORD6, 0(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
blt cr7, L(dP2x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD7, 4(rSTR1)
lwz rWORD8, 4(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
L(dP2e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 8(rSTR1)
lwz rWORD2, 8(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 12(rSTR1)
lwz rWORD4, 12(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#endif
bne cr6, L(dLcr6)
bne cr5, L(dLcr5)
b L(dLoop2)
/* Again we are on a early exit path (16-23 byte compare), we want to
only use volatile registers and avoid restoring non-volatile
registers. */
.align 4
L(dP2x):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 4(rSTR1)
lwz rWORD4, 4(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
slwi. r12, rN, 3
bne cr6, L(dLcr6x)
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#endif
bne cr1, L(dLcr1x)
subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bne L(d00)
li rRTN, 0
blr
/* Remainder is 12 */
.align 4
cfi_adjust_cfa_offset(64)
L(dP3):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 0(rSTR1)
lwz rWORD4, 0(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
L(dP3e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 4(rSTR1)
lwz rWORD6, 4(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
blt cr7, L(dP3x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD7, 8(rSTR1)
lwz rWORD8, 8(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 12(rSTR1)
lwz rWORD2, 12(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
bne cr1, L(dLcr1)
bne cr6, L(dLcr6)
b L(dLoop1)
/* Again we are on a early exit path (24-31 byte compare), we want to
only use volatile registers and avoid restoring non-volatile
registers. */
.align 4
L(dP3x):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 8(rSTR1)
lwz rWORD2, 8(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
slwi. r12, rN, 3
bne cr1, L(dLcr1x)
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
bne cr6, L(dLcr6x)
subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
bne cr7, L(dLcr7x)
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bne L(d00)
li rRTN, 0
blr
/* Count is a multiple of 16, remainder is 0 */
.align 4
cfi_adjust_cfa_offset(64)
L(dP4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 0(rSTR1)
lwz rWORD2, 0(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
L(dP4e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 4(rSTR1)
lwz rWORD4, 4(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 8(rSTR1)
lwz rWORD6, 8(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwzu rWORD7, 12(rSTR1)
lwzu rWORD8, 12(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr7, L(dLcr7)
bne cr1, L(dLcr1)
bdz- L(d24) /* Adjust CTR as we start with +4 */
/* This is the primary loop */
.align 4
L(dLoop):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
bne cr6, L(dLcr6)
L(dLoop1):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 8(rSTR1)
lwz rWORD4, 8(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
bne cr5, L(dLcr5)
L(dLoop2):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 12(rSTR1)
lwz rWORD6, 12(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr7, L(dLcr7)
L(dLoop3):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwzu rWORD7, 16(rSTR1)
lwzu rWORD8, 16(rSTR2)
#endif
bne- cr1, L(dLcr1)
cmplw cr7, rWORD1, rWORD2
bdnz+ L(dLoop)
L(dL4):
cmplw cr1, rWORD3, rWORD4
bne cr6, L(dLcr6)
cmplw cr6, rWORD5, rWORD6
bne cr5, L(dLcr5)
cmplw cr5, rWORD7, rWORD8
L(d44):
bne cr7, L(dLcr7)
L(d34):
bne cr1, L(dLcr1)
L(d24):
bne cr6, L(dLcr6)
L(d14):
slwi. r12, rN, 3
bne cr5, L(dLcr5)
L(d04):
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
beq L(zeroLength)
/* At this point we have a remainder of 1 to 3 bytes to compare. Since
we are aligned it is safe to load the whole word, and use
shift right to eliminate bits beyond the compare length. */
L(d00):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
srw rWORD1, rWORD1, rN
srw rWORD2, rWORD2, rN
sub rRTN, rWORD1, rWORD2
blr
.align 4
cfi_adjust_cfa_offset(64)
L(dLcr7):
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
L(dLcr7x):
li rRTN, 1
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bgtlr cr7
li rRTN, -1
blr
.align 4
cfi_adjust_cfa_offset(64)
L(dLcr1):
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
L(dLcr1x):
li rRTN, 1
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bgtlr cr1
li rRTN, -1
blr
.align 4
cfi_adjust_cfa_offset(64)
L(dLcr6):
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
L(dLcr6x):
li rRTN, 1
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bgtlr cr6
li rRTN, -1
blr
.align 4
cfi_adjust_cfa_offset(64)
L(dLcr5):
lwz rWORD7, 44(r1)
lwz rWORD8, 48(r1)
L(dLcr5x):
li rRTN, 1
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
bgtlr cr5
li rRTN, -1
blr
.align 4
L(bytealigned):
mtctr rN /* Power4 wants mtctr 1st in dispatch group */
/* We need to prime this loop. This loop is swing modulo scheduled
to avoid pipe delays. The dependent instruction latencies (load to
compare to conditional branch) is 2 to 3 cycles. In this loop each
dispatch group ends in a branch and takes 1 cycle. Effectively
the first iteration of the loop only serves to load operands and
branches based on compares are delayed until the next loop.
So we must precondition some registers and condition codes so that
we don't exit the loop early on the first iteration. */
lbz rWORD1, 0(rSTR1)
lbz rWORD2, 0(rSTR2)
bdz- L(b11)
cmplw cr7, rWORD1, rWORD2
lbz rWORD3, 1(rSTR1)
lbz rWORD4, 1(rSTR2)
bdz- L(b12)
cmplw cr1, rWORD3, rWORD4
lbzu rWORD5, 2(rSTR1)
lbzu rWORD6, 2(rSTR2)
bdz- L(b13)
.align 4
L(bLoop):
lbzu rWORD1, 1(rSTR1)
lbzu rWORD2, 1(rSTR2)
bne- cr7, L(bLcr7)
cmplw cr6, rWORD5, rWORD6
bdz- L(b3i)
lbzu rWORD3, 1(rSTR1)
lbzu rWORD4, 1(rSTR2)
bne- cr1, L(bLcr1)
cmplw cr7, rWORD1, rWORD2
bdz- L(b2i)
lbzu rWORD5, 1(rSTR1)
lbzu rWORD6, 1(rSTR2)
bne- cr6, L(bLcr6)
cmplw cr1, rWORD3, rWORD4
bdnz+ L(bLoop)
/* We speculatively loading bytes before we have tested the previous
bytes. But we must avoid overrunning the length (in the ctr) to
prevent these speculative loads from causing a segfault. In this
case the loop will exit early (before the all pending bytes are
tested. In this case we must complete the pending operations
before returning. */
L(b1i):
bne- cr7, L(bLcr7)
bne- cr1, L(bLcr1)
b L(bx56)
.align 4
L(b2i):
bne- cr6, L(bLcr6)
bne- cr7, L(bLcr7)
b L(bx34)
.align 4
L(b3i):
bne- cr1, L(bLcr1)
bne- cr6, L(bLcr6)
b L(bx12)
.align 4
L(bLcr7):
li rRTN, 1
bgtlr cr7
li rRTN, -1
blr
L(bLcr1):
li rRTN, 1
bgtlr cr1
li rRTN, -1
blr
L(bLcr6):
li rRTN, 1
bgtlr cr6
li rRTN, -1
blr
L(b13):
bne- cr7, L(bx12)
bne- cr1, L(bx34)
L(bx56):
sub rRTN, rWORD5, rWORD6
blr
nop
L(b12):
bne- cr7, L(bx12)
L(bx34):
sub rRTN, rWORD3, rWORD4
blr
L(b11):
L(bx12):
sub rRTN, rWORD1, rWORD2
blr
.align 4
L(zeroLength):
li rRTN, 0
blr
.align 4
/* At this point we know the strings have different alignment and the
compare length is at least 8 bytes. r12 contains the low order
2 bits of rSTR1 and cr5 contains the result of the logical compare
of r12 to 0. If r12 == 0 then rStr1 is word aligned and can
perform the Wunaligned loop.
Otherwise we know that rSTR1 is not already word aligned yet.
So we can force the string addresses to the next lower word
boundary and special case this first word using shift left to
eliminate bits preceding the first byte. Since we want to join the
normal (Wualigned) compare loop, starting at the second word,
we need to adjust the length (rN) and special case the loop
versioning for the first W. This ensures that the loop count is
correct and the first W (shifted) is in the expected resister pair. */
#define rSHL r29 /* Unaligned shift left count. */
#define rSHR r28 /* Unaligned shift right count. */
#define rWORD8_SHIFT r27 /* Left rotation temp for rWORD2. */
#define rWORD2_SHIFT r26 /* Left rotation temp for rWORD4. */
#define rWORD4_SHIFT r25 /* Left rotation temp for rWORD6. */
#define rWORD6_SHIFT r24 /* Left rotation temp for rWORD8. */
cfi_adjust_cfa_offset(64)
L(unaligned):
stw rSHL, 40(r1)
cfi_offset(rSHL, (40-64))
clrlwi rSHL, rSTR2, 30
stw rSHR, 36(r1)
cfi_offset(rSHR, (36-64))
beq cr5, L(Wunaligned)
stw rWORD8_SHIFT, 32(r1)
cfi_offset(rWORD8_SHIFT, (32-64))
/* Adjust the logical start of rSTR2 to compensate for the extra bits
in the 1st rSTR1 W. */
sub rWORD8_SHIFT, rSTR2, r12
/* But do not attempt to address the W before that W that contains
the actual start of rSTR2. */
clrrwi rSTR2, rSTR2, 2
stw rWORD2_SHIFT, 28(r1)
cfi_offset(rWORD2_SHIFT, (28-64))
/* Compute the left/right shift counts for the unaligned rSTR2,
compensating for the logical (W aligned) start of rSTR1. */
clrlwi rSHL, rWORD8_SHIFT, 30
clrrwi rSTR1, rSTR1, 2
stw rWORD4_SHIFT, 24(r1)
cfi_offset(rWORD4_SHIFT, (24-64))
slwi rSHL, rSHL, 3
cmplw cr5, rWORD8_SHIFT, rSTR2
add rN, rN, r12
slwi rWORD6, r12, 3
stw rWORD6_SHIFT, 20(r1)
cfi_offset(rWORD6_SHIFT, (20-64))
subfic rSHR, rSHL, 32
srwi r0, rN, 4 /* Divide by 16 */
andi. r12, rN, 12 /* Get the W remainder */
/* We normally need to load 2 Ws to start the unaligned rSTR2, but in
this special case those bits may be discarded anyway. Also we
must avoid loading a W where none of the bits are part of rSTR2 as
this may cross a page boundary and cause a page fault. */
li rWORD8, 0
blt cr5, L(dus0)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD8, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD8, 0(rSTR2)
addi rSTR2, rSTR2, 4
#endif
slw rWORD8, rWORD8, rSHL
L(dus0):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 0(rSTR1)
lwz rWORD2, 0(rSTR2)
#endif
cmplwi cr1, r12, 8
cmplwi cr7, rN, 16
srw r12, rWORD2, rSHR
clrlwi rN, rN, 30
beq L(duPs4)
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
or rWORD8, r12, rWORD8
bgt cr1, L(duPs3)
beq cr1, L(duPs2)
/* Remainder is 4 */
.align 4
L(dusP1):
slw rWORD8_SHIFT, rWORD2, rSHL
slw rWORD7, rWORD1, rWORD6
slw rWORD8, rWORD8, rWORD6
bge cr7, L(duP1e)
/* At this point we exit early with the first word compare
complete and remainder of 0 to 3 bytes. See L(du14) for details on
how we handle the remaining bytes. */
cmplw cr5, rWORD7, rWORD8
slwi. rN, rN, 3
bne cr5, L(duLcr5)
cmplw cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD2, 4(rSTR2)
#endif
srw r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 8 */
.align 4
L(duPs2):
slw rWORD6_SHIFT, rWORD2, rSHL
slw rWORD5, rWORD1, rWORD6
slw rWORD6, rWORD8, rWORD6
b L(duP2e)
/* Remainder is 12 */
.align 4
L(duPs3):
slw rWORD4_SHIFT, rWORD2, rSHL
slw rWORD3, rWORD1, rWORD6
slw rWORD4, rWORD8, rWORD6
b L(duP3e)
/* Count is a multiple of 16, remainder is 0 */
.align 4
L(duPs4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
or rWORD8, r12, rWORD8
slw rWORD2_SHIFT, rWORD2, rSHL
slw rWORD1, rWORD1, rWORD6
slw rWORD2, rWORD8, rWORD6
b L(duP4e)
/* At this point we know rSTR1 is word aligned and the
compare length is at least 8 bytes. */
.align 4
L(Wunaligned):
stw rWORD8_SHIFT, 32(r1)
cfi_offset(rWORD8_SHIFT, (32-64))
clrrwi rSTR2, rSTR2, 2
stw rWORD2_SHIFT, 28(r1)
cfi_offset(rWORD2_SHIFT, (28-64))
srwi r0, rN, 4 /* Divide by 16 */
stw rWORD4_SHIFT, 24(r1)
cfi_offset(rWORD4_SHIFT, (24-64))
andi. r12, rN, 12 /* Get the W remainder */
stw rWORD6_SHIFT, 20(r1)
cfi_offset(rWORD6_SHIFT, (20-64))
slwi rSHL, rSHL, 3
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD6, 0, rSTR2
addi rSTR2, rSTR2, 4
lwbrx rWORD8, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD6, 0(rSTR2)
lwzu rWORD8, 4(rSTR2)
#endif
cmplwi cr1, r12, 8
cmplwi cr7, rN, 16
clrlwi rN, rN, 30
subfic rSHR, rSHL, 32
slw rWORD6_SHIFT, rWORD6, rSHL
beq L(duP4)
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
bgt cr1, L(duP3)
beq cr1, L(duP2)
/* Remainder is 4 */
.align 4
L(duP1):
srw r12, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
addi rSTR1, rSTR1, 4
#else
lwz rWORD7, 0(rSTR1)
#endif
slw rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP1x)
L(duP1e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
srw r0, rWORD2, rSHR
slw rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 8(rSTR1)
lwz rWORD4, 8(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
srw r12, rWORD4, rSHR
slw rWORD4_SHIFT, rWORD4, rSHL
bne cr5, L(duLcr5)
or rWORD4, r12, rWORD2_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 12(rSTR1)
lwz rWORD6, 12(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
srw r0, rWORD6, rSHR
slw rWORD6_SHIFT, rWORD6, rSHL
bne cr7, L(duLcr7)
or rWORD6, r0, rWORD4_SHIFT
cmplw cr6, rWORD5, rWORD6
b L(duLoop3)
.align 4
/* At this point we exit early with the first word compare
complete and remainder of 0 to 3 bytes. See L(du14) for details on
how we handle the remaining bytes. */
L(duP1x):
cmplw cr5, rWORD7, rWORD8
slwi. rN, rN, 3
bne cr5, L(duLcr5)
cmplw cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD2, 8(rSTR2)
#endif
srw r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 8 */
.align 4
L(duP2):
srw r0, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
addi rSTR1, rSTR1, 4
#else
lwz rWORD5, 0(rSTR1)
#endif
or rWORD6, r0, rWORD6_SHIFT
slw rWORD6_SHIFT, rWORD8, rSHL
L(duP2e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD7, 4(rSTR1)
lwz rWORD8, 4(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
srw r12, rWORD8, rSHR
slw rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP2x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 8(rSTR1)
lwz rWORD2, 8(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
srw r0, rWORD2, rSHR
slw rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 12(rSTR1)
lwz rWORD4, 12(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
bne cr5, L(duLcr5)
srw r12, rWORD4, rSHR
slw rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#endif
cmplw cr1, rWORD3, rWORD4
b L(duLoop2)
.align 4
L(duP2x):
cmplw cr5, rWORD7, rWORD8
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#endif
bne cr6, L(duLcr6)
slwi. rN, rN, 3
bne cr5, L(duLcr5)
cmplw cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD2, 4(rSTR2)
#endif
srw r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 12 */
.align 4
L(duP3):
srw r12, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
addi rSTR1, rSTR1, 4
#else
lwz rWORD3, 0(rSTR1)
#endif
slw rWORD4_SHIFT, rWORD8, rSHL
or rWORD4, r12, rWORD6_SHIFT
L(duP3e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 4(rSTR1)
lwz rWORD6, 4(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
srw r0, rWORD6, rSHR
slw rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD7, 8(rSTR1)
lwz rWORD8, 8(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
bne cr1, L(duLcr1)
srw r12, rWORD8, rSHR
slw rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP3x)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 12(rSTR1)
lwz rWORD2, 12(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
srw r0, rWORD2, rSHR
slw rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
cmplw cr7, rWORD1, rWORD2
b L(duLoop1)
.align 4
L(duP3x):
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
#if 0
/* Huh? We've already branched on cr1! */
bne cr1, L(duLcr1)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
slwi. rN, rN, 3
bne cr5, L(duLcr5)
cmplw cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD2, 4(rSTR2)
#endif
srw r0, rWORD2, rSHR
b L(dutrim)
/* Count is a multiple of 16, remainder is 0 */
.align 4
L(duP4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
srw r0, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
addi rSTR1, rSTR1, 4
#else
lwz rWORD1, 0(rSTR1)
#endif
slw rWORD2_SHIFT, rWORD8, rSHL
or rWORD2, r0, rWORD6_SHIFT
L(duP4e):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 4(rSTR1)
lwz rWORD4, 4(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
srw r12, rWORD4, rSHR
slw rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 8(rSTR1)
lwz rWORD6, 8(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
bne cr7, L(duLcr7)
srw r0, rWORD6, rSHR
slw rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwzu rWORD7, 12(rSTR1)
lwzu rWORD8, 12(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
bne cr1, L(duLcr1)
srw r12, rWORD8, rSHR
slw rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
cmplw cr5, rWORD7, rWORD8
bdz- L(du24) /* Adjust CTR as we start with +4 */
/* This is the primary loop */
.align 4
L(duLoop):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
lwbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD1, 4(rSTR1)
lwz rWORD2, 4(rSTR2)
#endif
cmplw cr1, rWORD3, rWORD4
bne cr6, L(duLcr6)
srw r0, rWORD2, rSHR
slw rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
L(duLoop1):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD3, 0, rSTR1
lwbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD3, 8(rSTR1)
lwz rWORD4, 8(rSTR2)
#endif
cmplw cr6, rWORD5, rWORD6
bne cr5, L(duLcr5)
srw r12, rWORD4, rSHR
slw rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
L(duLoop2):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD5, 0, rSTR1
lwbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwz rWORD5, 12(rSTR1)
lwz rWORD6, 12(rSTR2)
#endif
cmplw cr5, rWORD7, rWORD8
bne cr7, L(duLcr7)
srw r0, rWORD6, rSHR
slw rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
L(duLoop3):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD7, 0, rSTR1
lwbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 4
addi rSTR2, rSTR2, 4
#else
lwzu rWORD7, 16(rSTR1)
lwzu rWORD8, 16(rSTR2)
#endif
cmplw cr7, rWORD1, rWORD2
bne- cr1, L(duLcr1)
srw r12, rWORD8, rSHR
slw rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
bdnz+ L(duLoop)
L(duL4):
#if 0
/* Huh? We've already branched on cr1! */
bne cr1, L(duLcr1)
#endif
cmplw cr1, rWORD3, rWORD4
bne cr6, L(duLcr6)
cmplw cr6, rWORD5, rWORD6
bne cr5, L(duLcr5)
cmplw cr5, rWORD7, rWORD8
L(du44):
bne cr7, L(duLcr7)
L(du34):
bne cr1, L(duLcr1)
L(du24):
bne cr6, L(duLcr6)
L(du14):
slwi. rN, rN, 3
bne cr5, L(duLcr5)
/* At this point we have a remainder of 1 to 3 bytes to compare. We use
shift right to eliminate bits beyond the compare length.
This allows the use of word subtract to compute the final result.
However it may not be safe to load rWORD2 which may be beyond the
string length. So we compare the bit length of the remainder to
the right shift count (rSHR). If the bit count is less than or equal
we do not need to load rWORD2 (all significant bits are already in
rWORD8_SHIFT). */
cmplw cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 4
#else
lwz rWORD2, 4(rSTR2)
#endif
srw r0, rWORD2, rSHR
.align 4
L(dutrim):
#ifdef __LITTLE_ENDIAN__
lwbrx rWORD1, 0, rSTR1
#else
lwz rWORD1, 4(rSTR1)
#endif
lwz rWORD8, 48(r1)
subfic rN, rN, 32 /* Shift count is 32 - (rN * 8). */
or rWORD2, r0, rWORD8_SHIFT
lwz rWORD7, 44(r1)
lwz rSHL, 40(r1)
srw rWORD1, rWORD1, rN
srw rWORD2, rWORD2, rN
lwz rSHR, 36(r1)
lwz rWORD8_SHIFT, 32(r1)
sub rRTN, rWORD1, rWORD2
b L(dureturn26)
.align 4
L(duLcr7):
lwz rWORD8, 48(r1)
lwz rWORD7, 44(r1)
li rRTN, 1
bgt cr7, L(dureturn29)
lwz rSHL, 40(r1)
lwz rSHR, 36(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr1):
lwz rWORD8, 48(r1)
lwz rWORD7, 44(r1)
li rRTN, 1
bgt cr1, L(dureturn29)
lwz rSHL, 40(r1)
lwz rSHR, 36(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr6):
lwz rWORD8, 48(r1)
lwz rWORD7, 44(r1)
li rRTN, 1
bgt cr6, L(dureturn29)
lwz rSHL, 40(r1)
lwz rSHR, 36(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr5):
lwz rWORD8, 48(r1)
lwz rWORD7, 44(r1)
li rRTN, 1
bgt cr5, L(dureturn29)
lwz rSHL, 40(r1)
lwz rSHR, 36(r1)
li rRTN, -1
b L(dureturn27)
.align 3
L(duZeroReturn):
li rRTN, 0
.align 4
L(dureturn):
lwz rWORD8, 48(r1)
lwz rWORD7, 44(r1)
L(dureturn29):
lwz rSHL, 40(r1)
lwz rSHR, 36(r1)
L(dureturn27):
lwz rWORD8_SHIFT, 32(r1)
L(dureturn26):
lwz rWORD2_SHIFT, 28(r1)
L(dureturn25):
lwz rWORD4_SHIFT, 24(r1)
lwz rWORD6_SHIFT, 20(r1)
addi 1, 1, 64
cfi_adjust_cfa_offset(-64)
blr
END (memcmp)
libc_hidden_builtin_def (memcmp)
weak_alias (memcmp, bcmp)
|