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
|
/* Optimized memcmp implementation for PowerPC64.
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 3
#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
cmpldi cr6, rN, 0
cmpldi cr1, rN, 12
clrldi. r0, r0, 61
clrldi r12, rSTR1, 61
cmpldi 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)
std rWORD8, -8(r1)
cfi_offset(rWORD8, -8)
std rWORD7, -16(r1)
cfi_offset(rWORD7, -16)
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
3 bits of rSTR1 and cr5 contains the result of the logical compare
of r12 to 0. If r12 == 0 then we are already double word
aligned and can perform the DW aligned loop.
Otherwise we know the two strings have the same alignment (but not
yet DW). So we force the string addresses to the next lower DW
boundary and special case this first DW using shift left to
eliminate bits preceding the first byte. Since we want to join the
normal (DW aligned) compare loop, starting at the second double word,
we need to adjust the length (rN) and special case the loop
versioning for the first DW. This ensures that the loop count is
correct and the first DW (shifted) is in the expected register pair. */
.align 4
L(samealignment):
clrrdi rSTR1, rSTR1, 3
clrrdi rSTR2, rSTR2, 3
beq cr5, L(DWaligned)
add rN, rN, r12
sldi rWORD6, r12, 3
srdi r0, rN, 5 /* Divide by 32 */
andi. r12, rN, 24 /* Get the DW remainder */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 0(rSTR1)
ld rWORD2, 0(rSTR2)
#endif
cmpldi cr1, r12, 16
cmpldi cr7, rN, 32
clrldi rN, rN, 61
beq L(dPs4)
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
bgt cr1, L(dPs3)
beq cr1, L(dPs2)
/* Remainder is 8 */
.align 3
L(dsP1):
sld rWORD5, rWORD1, rWORD6
sld rWORD6, rWORD2, rWORD6
cmpld cr5, rWORD5, rWORD6
blt cr7, L(dP1x)
/* Do something useful in this cycle since we have to branch anyway. */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
b L(dP1e)
/* Remainder is 16 */
.align 4
L(dPs2):
sld rWORD5, rWORD1, rWORD6
sld rWORD6, rWORD2, rWORD6
cmpld cr6, rWORD5, rWORD6
blt cr7, L(dP2x)
/* Do something useful in this cycle since we have to branch anyway. */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD7, 8(rSTR1)
ld rWORD8, 8(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
b L(dP2e)
/* Remainder is 24 */
.align 4
L(dPs3):
sld rWORD3, rWORD1, rWORD6
sld rWORD4, rWORD2, rWORD6
cmpld cr1, rWORD3, rWORD4
b L(dP3e)
/* Count is a multiple of 32, remainder is 0 */
.align 4
L(dPs4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
sld rWORD1, rWORD1, rWORD6
sld rWORD2, rWORD2, rWORD6
cmpld cr7, rWORD1, rWORD2
b L(dP4e)
/* At this point we know both strings are double word aligned and the
compare length is at least 8 bytes. */
.align 4
L(DWaligned):
andi. r12, rN, 24 /* Get the DW remainder */
srdi r0, rN, 5 /* Divide by 32 */
cmpldi cr1, r12, 16
cmpldi cr7, rN, 32
clrldi rN, rN, 61
beq L(dP4)
bgt cr1, L(dP3)
beq cr1, L(dP2)
/* Remainder is 8 */
.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__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 0(rSTR1)
ld rWORD6, 0(rSTR2)
#endif
cmpld cr5, rWORD5, rWORD6
blt cr7, L(dP1x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
L(dP1e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 16(rSTR1)
ld rWORD4, 16(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 24(rSTR1)
ld rWORD6, 24(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
bne cr5, L(dLcr5x)
bne cr7, L(dLcr7x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ldu rWORD7, 32(rSTR1)
ldu rWORD8, 32(rSTR2)
#endif
bne cr1, L(dLcr1)
cmpld cr5, rWORD7, rWORD8
bdnz L(dLoop)
bne cr6, L(dLcr6)
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
.align 3
L(dP1x):
sldi. r12, rN, 3
bne cr5, L(dLcr5x)
subfic rN, r12, 64 /* Shift count is 64 - (rN * 8). */
bne L(d00)
li rRTN, 0
blr
/* Remainder is 16 */
.align 4
L(dP2):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 0(rSTR1)
ld rWORD6, 0(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
blt cr7, L(dP2x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD7, 8(rSTR1)
ld rWORD8, 8(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
L(dP2e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 16(rSTR1)
ld rWORD2, 16(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 24(rSTR1)
ld rWORD4, 24(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#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__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 8(rSTR1)
ld rWORD4, 8(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
sldi. r12, rN, 3
bne cr6, L(dLcr6x)
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
bne cr1, L(dLcr1x)
subfic rN, r12, 64 /* Shift count is 64 - (rN * 8). */
bne L(d00)
li rRTN, 0
blr
/* Remainder is 24 */
.align 4
L(dP3):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 0(rSTR1)
ld rWORD4, 0(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
L(dP3e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 8(rSTR1)
ld rWORD6, 8(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
blt cr7, L(dP3x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD7, 16(rSTR1)
ld rWORD8, 16(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 24(rSTR1)
ld rWORD2, 24(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#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__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 16(rSTR1)
ld rWORD2, 16(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
sldi. r12, rN, 3
bne cr1, L(dLcr1x)
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#endif
bne cr6, L(dLcr6x)
subfic rN, r12, 64 /* Shift count is 64 - (rN * 8). */
bne cr7, L(dLcr7x)
bne L(d00)
li rRTN, 0
blr
/* Count is a multiple of 32, remainder is 0 */
.align 4
L(dP4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 0(rSTR1)
ld rWORD2, 0(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
L(dP4e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 8(rSTR1)
ld rWORD4, 8(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 16(rSTR1)
ld rWORD6, 16(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ldu rWORD7, 24(rSTR1)
ldu rWORD8, 24(rSTR2)
#endif
cmpld 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__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
bne cr6, L(dLcr6)
L(dLoop1):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 16(rSTR1)
ld rWORD4, 16(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
bne cr5, L(dLcr5)
L(dLoop2):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 24(rSTR1)
ld rWORD6, 24(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
bne cr7, L(dLcr7)
L(dLoop3):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ldu rWORD7, 32(rSTR1)
ldu rWORD8, 32(rSTR2)
#endif
bne- cr1, L(dLcr1)
cmpld cr7, rWORD1, rWORD2
bdnz+ L(dLoop)
L(dL4):
cmpld cr1, rWORD3, rWORD4
bne cr6, L(dLcr6)
cmpld cr6, rWORD5, rWORD6
bne cr5, L(dLcr5)
cmpld cr5, rWORD7, rWORD8
L(d44):
bne cr7, L(dLcr7)
L(d34):
bne cr1, L(dLcr1)
L(d24):
bne cr6, L(dLcr6)
L(d14):
sldi. r12, rN, 3
bne cr5, L(dLcr5)
L(d04):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
subfic rN, r12, 64 /* Shift count is 64 - (rN * 8). */
beq L(zeroLength)
/* At this point we have a remainder of 1 to 7 bytes to compare. Since
we are aligned it is safe to load the whole double word, and use
shift right double to eliminate bits beyond the compare length. */
L(d00):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
srd rWORD1, rWORD1, rN
srd rWORD2, rWORD2, rN
cmpld cr7, rWORD1, rWORD2
bne cr7, L(dLcr7x)
li rRTN, 0
blr
.align 4
L(dLcr7):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
L(dLcr7x):
li rRTN, 1
bgtlr cr7
li rRTN, -1
blr
.align 4
L(dLcr1):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
L(dLcr1x):
li rRTN, 1
bgtlr cr1
li rRTN, -1
blr
.align 4
L(dLcr6):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
L(dLcr6x):
li rRTN, 1
bgtlr cr6
li rRTN, -1
blr
.align 4
L(dLcr5):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
L(dLcr5x):
li rRTN, 1
bgtlr cr5
li rRTN, -1
blr
.align 4
L(bytealigned):
mtctr rN /* Power4 wants mtctr 1st in dispatch group */
#if 0
/* Huh? We've already branched on cr6! */
beq- cr6, L(zeroLength)
#endif
/* 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)
cmpld cr7, rWORD1, rWORD2
lbz rWORD3, 1(rSTR1)
lbz rWORD4, 1(rSTR2)
bdz- L(b12)
cmpld 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)
cmpld cr6, rWORD5, rWORD6
bdz- L(b3i)
lbzu rWORD3, 1(rSTR1)
lbzu rWORD4, 1(rSTR2)
bne- cr1, L(bLcr1)
cmpld cr7, rWORD1, rWORD2
bdz- L(b2i)
lbzu rWORD5, 1(rSTR1)
lbzu rWORD6, 1(rSTR2)
bne- cr6, L(bLcr6)
cmpld 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
3 bits of rSTR1 and cr5 contains the result of the logical compare
of r12 to 0. If r12 == 0 then rStr1 is double word
aligned and can perform the DWunaligned loop.
Otherwise we know that rSTR1 is not already DW aligned yet.
So we can force the string addresses to the next lower DW
boundary and special case this first DW using shift left to
eliminate bits preceding the first byte. Since we want to join the
normal (DWaligned) compare loop, starting at the second double word,
we need to adjust the length (rN) and special case the loop
versioning for the first DW. This ensures that the loop count is
correct and the first DW (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. */
L(unaligned):
std rSHL, -24(r1)
cfi_offset(rSHL, -24)
clrldi rSHL, rSTR2, 61
beq- cr6, L(duzeroLength)
std rSHR, -32(r1)
cfi_offset(rSHR, -32)
beq cr5, L(DWunaligned)
std rWORD8_SHIFT, -40(r1)
cfi_offset(rWORD8_SHIFT, -40)
/* Adjust the logical start of rSTR2 to compensate for the extra bits
in the 1st rSTR1 DW. */
sub rWORD8_SHIFT, rSTR2, r12
/* But do not attempt to address the DW before that DW that contains
the actual start of rSTR2. */
clrrdi rSTR2, rSTR2, 3
std rWORD2_SHIFT, -48(r1)
cfi_offset(rWORD2_SHIFT, -48)
/* Compute the left/right shift counts for the unaligned rSTR2,
compensating for the logical (DW aligned) start of rSTR1. */
clrldi rSHL, rWORD8_SHIFT, 61
clrrdi rSTR1, rSTR1, 3
std rWORD4_SHIFT, -56(r1)
cfi_offset(rWORD4_SHIFT, -56)
sldi rSHL, rSHL, 3
cmpld cr5, rWORD8_SHIFT, rSTR2
add rN, rN, r12
sldi rWORD6, r12, 3
std rWORD6_SHIFT, -64(r1)
cfi_offset(rWORD6_SHIFT, -64)
subfic rSHR, rSHL, 64
srdi r0, rN, 5 /* Divide by 32 */
andi. r12, rN, 24 /* Get the DW remainder */
/* We normally need to load 2 DWs to start the unaligned rSTR2, but in
this special case those bits may be discarded anyway. Also we
must avoid loading a DW 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__
ldbrx rWORD8, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD8, 0(rSTR2)
addi rSTR2, rSTR2, 8
#endif
sld rWORD8, rWORD8, rSHL
L(dus0):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 0(rSTR1)
ld rWORD2, 0(rSTR2)
#endif
cmpldi cr1, r12, 16
cmpldi cr7, rN, 32
srd r12, rWORD2, rSHR
clrldi rN, rN, 61
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 8 */
.align 4
L(dusP1):
sld rWORD8_SHIFT, rWORD2, rSHL
sld rWORD7, rWORD1, rWORD6
sld rWORD8, rWORD8, rWORD6
bge cr7, L(duP1e)
/* At this point we exit early with the first double word compare
complete and remainder of 0 to 7 bytes. See L(du14) for details on
how we handle the remaining bytes. */
cmpld cr5, rWORD7, rWORD8
sldi. rN, rN, 3
bne cr5, L(duLcr5)
cmpld cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD2, 8(rSTR2)
#endif
srd r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 16 */
.align 4
L(duPs2):
sld rWORD6_SHIFT, rWORD2, rSHL
sld rWORD5, rWORD1, rWORD6
sld rWORD6, rWORD8, rWORD6
b L(duP2e)
/* Remainder is 24 */
.align 4
L(duPs3):
sld rWORD4_SHIFT, rWORD2, rSHL
sld rWORD3, rWORD1, rWORD6
sld rWORD4, rWORD8, rWORD6
b L(duP3e)
/* Count is a multiple of 32, remainder is 0 */
.align 4
L(duPs4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
or rWORD8, r12, rWORD8
sld rWORD2_SHIFT, rWORD2, rSHL
sld rWORD1, rWORD1, rWORD6
sld rWORD2, rWORD8, rWORD6
b L(duP4e)
/* At this point we know rSTR1 is double word aligned and the
compare length is at least 8 bytes. */
.align 4
L(DWunaligned):
std rWORD8_SHIFT, -40(r1)
cfi_offset(rWORD8_SHIFT, -40)
clrrdi rSTR2, rSTR2, 3
std rWORD2_SHIFT, -48(r1)
cfi_offset(rWORD2_SHIFT, -48)
srdi r0, rN, 5 /* Divide by 32 */
std rWORD4_SHIFT, -56(r1)
cfi_offset(rWORD4_SHIFT, -56)
andi. r12, rN, 24 /* Get the DW remainder */
std rWORD6_SHIFT, -64(r1)
cfi_offset(rWORD6_SHIFT, -64)
sldi rSHL, rSHL, 3
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD6, 0, rSTR2
addi rSTR2, rSTR2, 8
ldbrx rWORD8, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD6, 0(rSTR2)
ldu rWORD8, 8(rSTR2)
#endif
cmpldi cr1, r12, 16
cmpldi cr7, rN, 32
clrldi rN, rN, 61
subfic rSHR, rSHL, 64
sld 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 8 */
.align 4
L(duP1):
srd r12, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
addi rSTR1, rSTR1, 8
#else
ld rWORD7, 0(rSTR1)
#endif
sld rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP1x)
L(duP1e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
srd r0, rWORD2, rSHR
sld rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 16(rSTR1)
ld rWORD4, 16(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
srd r12, rWORD4, rSHR
sld rWORD4_SHIFT, rWORD4, rSHL
bne cr5, L(duLcr5)
or rWORD4, r12, rWORD2_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 24(rSTR1)
ld rWORD6, 24(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
srd r0, rWORD6, rSHR
sld rWORD6_SHIFT, rWORD6, rSHL
bne cr7, L(duLcr7)
or rWORD6, r0, rWORD4_SHIFT
cmpld cr6, rWORD5, rWORD6
b L(duLoop3)
.align 4
/* At this point we exit early with the first double word compare
complete and remainder of 0 to 7 bytes. See L(du14) for details on
how we handle the remaining bytes. */
L(duP1x):
cmpld cr5, rWORD7, rWORD8
sldi. rN, rN, 3
bne cr5, L(duLcr5)
cmpld cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD2, 8(rSTR2)
#endif
srd r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 16 */
.align 4
L(duP2):
srd r0, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
addi rSTR1, rSTR1, 8
#else
ld rWORD5, 0(rSTR1)
#endif
or rWORD6, r0, rWORD6_SHIFT
sld rWORD6_SHIFT, rWORD8, rSHL
L(duP2e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD7, 8(rSTR1)
ld rWORD8, 8(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
srd r12, rWORD8, rSHR
sld rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP2x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 16(rSTR1)
ld rWORD2, 16(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
srd r0, rWORD2, rSHR
sld rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 24(rSTR1)
ld rWORD4, 24(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
bne cr5, L(duLcr5)
srd r12, rWORD4, rSHR
sld rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
cmpld cr1, rWORD3, rWORD4
b L(duLoop2)
.align 4
L(duP2x):
cmpld cr5, rWORD7, rWORD8
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#endif
bne cr6, L(duLcr6)
sldi. rN, rN, 3
bne cr5, L(duLcr5)
cmpld cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD2, 8(rSTR2)
#endif
srd r0, rWORD2, rSHR
b L(dutrim)
/* Remainder is 24 */
.align 4
L(duP3):
srd r12, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
addi rSTR1, rSTR1, 8
#else
ld rWORD3, 0(rSTR1)
#endif
sld rWORD4_SHIFT, rWORD8, rSHL
or rWORD4, r12, rWORD6_SHIFT
L(duP3e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 8(rSTR1)
ld rWORD6, 8(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
srd r0, rWORD6, rSHR
sld rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD7, 16(rSTR1)
ld rWORD8, 16(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
bne cr1, L(duLcr1)
srd r12, rWORD8, rSHR
sld rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
blt cr7, L(duP3x)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 24(rSTR1)
ld rWORD2, 24(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
srd r0, rWORD2, rSHR
sld rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#endif
cmpld cr7, rWORD1, rWORD2
b L(duLoop1)
.align 4
L(duP3x):
#ifndef __LITTLE_ENDIAN__
addi rSTR1, rSTR1, 16
addi rSTR2, rSTR2, 16
#endif
#if 0
/* Huh? We've already branched on cr1! */
bne cr1, L(duLcr1)
#endif
cmpld cr5, rWORD7, rWORD8
bne cr6, L(duLcr6)
sldi. rN, rN, 3
bne cr5, L(duLcr5)
cmpld cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD2, 8(rSTR2)
#endif
srd r0, rWORD2, rSHR
b L(dutrim)
/* Count is a multiple of 32, remainder is 0 */
.align 4
L(duP4):
mtctr r0 /* Power4 wants mtctr 1st in dispatch group */
srd r0, rWORD8, rSHR
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
addi rSTR1, rSTR1, 8
#else
ld rWORD1, 0(rSTR1)
#endif
sld rWORD2_SHIFT, rWORD8, rSHL
or rWORD2, r0, rWORD6_SHIFT
L(duP4e):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 8(rSTR1)
ld rWORD4, 8(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
srd r12, rWORD4, rSHR
sld rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 16(rSTR1)
ld rWORD6, 16(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
bne cr7, L(duLcr7)
srd r0, rWORD6, rSHR
sld rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ldu rWORD7, 24(rSTR1)
ldu rWORD8, 24(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
bne cr1, L(duLcr1)
srd r12, rWORD8, rSHR
sld rWORD8_SHIFT, rWORD8, rSHL
or rWORD8, r12, rWORD6_SHIFT
cmpld 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__
ldbrx rWORD1, 0, rSTR1
ldbrx rWORD2, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD1, 8(rSTR1)
ld rWORD2, 8(rSTR2)
#endif
cmpld cr1, rWORD3, rWORD4
bne cr6, L(duLcr6)
srd r0, rWORD2, rSHR
sld rWORD2_SHIFT, rWORD2, rSHL
or rWORD2, r0, rWORD8_SHIFT
L(duLoop1):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD3, 0, rSTR1
ldbrx rWORD4, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD3, 16(rSTR1)
ld rWORD4, 16(rSTR2)
#endif
cmpld cr6, rWORD5, rWORD6
bne cr5, L(duLcr5)
srd r12, rWORD4, rSHR
sld rWORD4_SHIFT, rWORD4, rSHL
or rWORD4, r12, rWORD2_SHIFT
L(duLoop2):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD5, 0, rSTR1
ldbrx rWORD6, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ld rWORD5, 24(rSTR1)
ld rWORD6, 24(rSTR2)
#endif
cmpld cr5, rWORD7, rWORD8
bne cr7, L(duLcr7)
srd r0, rWORD6, rSHR
sld rWORD6_SHIFT, rWORD6, rSHL
or rWORD6, r0, rWORD4_SHIFT
L(duLoop3):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD7, 0, rSTR1
ldbrx rWORD8, 0, rSTR2
addi rSTR1, rSTR1, 8
addi rSTR2, rSTR2, 8
#else
ldu rWORD7, 32(rSTR1)
ldu rWORD8, 32(rSTR2)
#endif
cmpld cr7, rWORD1, rWORD2
bne- cr1, L(duLcr1)
srd r12, rWORD8, rSHR
sld 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
cmpld cr1, rWORD3, rWORD4
bne cr6, L(duLcr6)
cmpld cr6, rWORD5, rWORD6
bne cr5, L(duLcr5)
cmpld cr5, rWORD7, rWORD8
L(du44):
bne cr7, L(duLcr7)
L(du34):
bne cr1, L(duLcr1)
L(du24):
bne cr6, L(duLcr6)
L(du14):
sldi. rN, rN, 3
bne cr5, L(duLcr5)
/* At this point we have a remainder of 1 to 7 bytes to compare. We use
shift right double to eliminate bits beyond the compare length.
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). */
cmpld cr7, rN, rSHR
beq L(duZeroReturn)
li r0, 0
ble cr7, L(dutrim)
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD2, 0, rSTR2
addi rSTR2, rSTR2, 8
#else
ld rWORD2, 8(rSTR2)
#endif
srd r0, rWORD2, rSHR
.align 4
L(dutrim):
#ifdef __LITTLE_ENDIAN__
ldbrx rWORD1, 0, rSTR1
#else
ld rWORD1, 8(rSTR1)
#endif
ld rWORD8, -8(r1)
subfic rN, rN, 64 /* Shift count is 64 - (rN * 8). */
or rWORD2, r0, rWORD8_SHIFT
ld rWORD7, -16(r1)
ld rSHL, -24(r1)
srd rWORD1, rWORD1, rN
srd rWORD2, rWORD2, rN
ld rSHR, -32(r1)
ld rWORD8_SHIFT, -40(r1)
li rRTN, 0
cmpld cr7, rWORD1, rWORD2
ld rWORD2_SHIFT, -48(r1)
ld rWORD4_SHIFT, -56(r1)
beq cr7, L(dureturn24)
li rRTN, 1
ld rWORD6_SHIFT, -64(r1)
bgtlr cr7
li rRTN, -1
blr
.align 4
L(duLcr7):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
li rRTN, 1
bgt cr7, L(dureturn29)
ld rSHL, -24(r1)
ld rSHR, -32(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr1):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
li rRTN, 1
bgt cr1, L(dureturn29)
ld rSHL, -24(r1)
ld rSHR, -32(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr6):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
li rRTN, 1
bgt cr6, L(dureturn29)
ld rSHL, -24(r1)
ld rSHR, -32(r1)
li rRTN, -1
b L(dureturn27)
.align 4
L(duLcr5):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
li rRTN, 1
bgt cr5, L(dureturn29)
ld rSHL, -24(r1)
ld rSHR, -32(r1)
li rRTN, -1
b L(dureturn27)
.align 3
L(duZeroReturn):
li rRTN, 0
.align 4
L(dureturn):
ld rWORD8, -8(r1)
ld rWORD7, -16(r1)
L(dureturn29):
ld rSHL, -24(r1)
ld rSHR, -32(r1)
L(dureturn27):
ld rWORD8_SHIFT, -40(r1)
L(dureturn26):
ld rWORD2_SHIFT, -48(r1)
L(dureturn25):
ld rWORD4_SHIFT, -56(r1)
L(dureturn24):
ld rWORD6_SHIFT, -64(r1)
blr
L(duzeroLength):
li rRTN, 0
blr
END (memcmp)
libc_hidden_builtin_def (memcmp)
weak_alias (memcmp, bcmp)
|