485 lines
23 KiB
ArmAsm
485 lines
23 KiB
ArmAsm
/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
|
||
│vi: set et ft=asm ts=8 sw=8 fenc=utf-8 :vi│
|
||
╞══════════════════════════════════════════════════════════════════════════════╡
|
||
│ Copyright 2020 Justine Alexandra Roberts Tunney │
|
||
│ │
|
||
│ This program is free software; you can redistribute it and/or modify │
|
||
│ it under the terms of the GNU General Public License as published by │
|
||
│ the Free Software Foundation; version 2 of the License. │
|
||
│ │
|
||
│ This program 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 │
|
||
│ General Public License for more details. │
|
||
│ │
|
||
│ You should have received a copy of the GNU General Public License │
|
||
│ along with this program; if not, write to the Free Software │
|
||
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
|
||
│ 02110-1301 USA │
|
||
╚─────────────────────────────────────────────────────────────────────────────*/
|
||
#include "libc/nexgen32e/x86feature.h"
|
||
#include "libc/nexgen32e/macros.h"
|
||
#include "libc/macros.h"
|
||
.source __FILE__
|
||
|
||
/ Returns pointer to first instance of character.
|
||
/
|
||
/ @param rdi is a non-null NUL-terminated string pointer
|
||
/ @param esi is the search byte
|
||
/ @return rax points to character, or to NUL byte if not found
|
||
/ @note this won't return NULL if search character is NUL
|
||
strchrnul:
|
||
.leafprologue
|
||
.profilable
|
||
or $-1,%r9
|
||
jmp 0f
|
||
.endfn strchrnul,globl
|
||
|
||
/ Returns pointer to first instance of character, the BSD way.
|
||
/
|
||
/ @param rdi is a non-null NUL-terminated string pointer
|
||
/ @param esi is the search byte
|
||
/ @return rax points to first result, or NULL if not found
|
||
/ @note this won't return NULL if search character is NUL
|
||
index: nop
|
||
/ 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn index,globl
|
||
|
||
/ Returns pointer to first instance of character.
|
||
/
|
||
/ @param rdi is a non-null NUL-terminated string pointer
|
||
/ @param esi is the search byte
|
||
/ @return rax points to first result, or NULL if not found
|
||
/ @note this won't return NULL if search character is NUL
|
||
/ @asyncsignalsafe
|
||
strchr: .leafprologue
|
||
.profilable
|
||
xor %r9d,%r9d
|
||
0: movzbl %sil,%edx
|
||
or $-1,%rsi
|
||
xor %r8,%r8
|
||
jmp strsak
|
||
.endfn strchr,globl
|
||
|
||
/ Returns pointer to first instance of character in range.
|
||
/
|
||
/ @param rdi is a non-null pointer to memory
|
||
/ @param esi is the search byte
|
||
/ @return rax points to byte if found, or else undefined behavior
|
||
rawmemchr:
|
||
or $-1,%rdx
|
||
/ 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn rawmemchr,globl
|
||
|
||
/ Returns pointer to first instance of character in range.
|
||
/
|
||
/ @param rdi is a non-null pointer to memory
|
||
/ @param esi is the search byte
|
||
/ @param rdx is length of memory in bytes
|
||
/ @return rax points to byte if found or NULL
|
||
/ @asyncsignalsafe
|
||
memchr: .leafprologue
|
||
.profilable
|
||
xchg %rsi,%rdx
|
||
mov %dl,%dh
|
||
xor %r8,%r8
|
||
xor %r10,%r10
|
||
jmp strsak
|
||
.endfn memchr,globl
|
||
|
||
/ Returns length of NUL-terminated string w/ security blankets.
|
||
/
|
||
/ This is like strnlen() except it'll return 0 if (1) RDI is NULL
|
||
/ or (2) a NUL-terminator wasn't found in the first RSI bytes.
|
||
/
|
||
/ @param rdi is a nullable NUL-terminated string pointer
|
||
/ @param rsi is the maximum number of bytes to consider
|
||
/ @return rax is the number of bytes, excluding the NUL
|
||
strnlen_s:
|
||
.leafprologue
|
||
.profilable
|
||
xor %eax,%eax
|
||
xor %r10d,%r10d
|
||
test %rdi,%rdi
|
||
jnz 0f
|
||
.leafepilogue
|
||
.endfn strnlen_s,globl
|
||
|
||
/ Returns length of NUL-terminated memory, with limit.
|
||
/
|
||
/ @param rdi is non-null memory
|
||
/ @param rsi is the maximum number of bytes to consider
|
||
/ @return rax is the number of bytes, excluding the NUL
|
||
/ @asyncsignalsafe
|
||
strnlen:.leafprologue
|
||
.profilable
|
||
or $-1,%r10
|
||
0: xor %edx,%edx
|
||
mov %rdi,%r8
|
||
/ 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn strnlen,globl
|
||
|
||
/ Swiss army knife of string character scanning.
|
||
/ Fourteen fast functions in one.
|
||
/
|
||
/ @param rdi is non-null string memory
|
||
/ @param rsi is max number of bytes to consider
|
||
/ @param dl is search character #1
|
||
/ @param dh is search character #2
|
||
/ @param r8 is subtracted from result (for length vs. pointer)
|
||
/ @param r9 masks result if DH is found (for NUL vs. NULL)
|
||
/ @param r10 masks result on bytes exhausted (for length v. NULL)
|
||
/ @return rax end pointer after r8/r9/r10 modifications
|
||
strsak: lea -1(%rdi),%rax
|
||
1: add $1,%rax
|
||
sub $1,%rsi
|
||
jb .Lend
|
||
test $31,%al
|
||
jz .Lfast
|
||
.Lbyte: mov (%rax),%cl
|
||
cmp %cl,%dl
|
||
je .Ldone
|
||
cmp %cl,%dh
|
||
je .Lnul
|
||
jmp 1b
|
||
.Ldone: sub %r8,%rax
|
||
jmp .Lret
|
||
.Lend: mov %r10,%r9
|
||
.Lnul: sub %r8,%rax
|
||
and %r9,%rax
|
||
.Lret: .leafepilogue
|
||
.Lslow: add $32,%rsi
|
||
jmp .Lbyte
|
||
.Lfast: movzbl %dl,%ecx
|
||
movd %ecx,%xmm0
|
||
movzbl %dh,%ecx
|
||
movd %ecx,%xmm1
|
||
sub $32,%rax
|
||
#if !X86_NEED(AVX2)
|
||
testb X86_HAVE(AVX2)+kCpuids(%rip)
|
||
jz .Lsse2
|
||
#endif
|
||
vpbroadcastb %xmm0,%ymm0
|
||
vpbroadcastb %xmm1,%ymm1
|
||
1: add $32,%rax
|
||
sub $32,%rsi
|
||
9: jb .Lslow
|
||
vmovdqa (%rax),%ymm2
|
||
vpcmpeqb %ymm0,%ymm2,%ymm3
|
||
vpcmpeqb %ymm1,%ymm2,%ymm2
|
||
vpor %ymm3,%ymm2,%ymm2
|
||
vpmovmskb %ymm2,%ecx
|
||
bsf %ecx,%ecx
|
||
je 1b
|
||
vzeroupper
|
||
2: add %rcx,%rax
|
||
jmp .Lbyte
|
||
#if !X86_NEED(AVX2)
|
||
.Lsse2: pbroadcastb %xmm0
|
||
pbroadcastb %xmm1
|
||
1: add $32,%rax
|
||
sub $32,%rsi
|
||
jb 9b
|
||
movdqa (%rax),%xmm2
|
||
movdqa 16(%rax),%xmm3
|
||
movdqa %xmm3,%xmm4
|
||
pcmpeqb %xmm0,%xmm3
|
||
pcmpeqb %xmm1,%xmm4
|
||
por %xmm4,%xmm3
|
||
pmovmskb %xmm3,%ecx
|
||
shl $16,%ecx
|
||
movdqa %xmm2,%xmm4
|
||
pcmpeqb %xmm0,%xmm2
|
||
pcmpeqb %xmm1,%xmm4
|
||
por %xmm4,%xmm2
|
||
pmovmskb %xmm2,%r11d
|
||
or %r11d,%ecx
|
||
bsf %ecx,%ecx
|
||
je 1b
|
||
jmp 2b
|
||
#endif
|
||
.endfn strsak,globl,hidden
|
||
|
||
/* benchmarked on intel core i7-6700 @ 3.40GHz (skylake)
|
||
includes function call overhead (unless marked otherwise)
|
||
|
||
your strlen, &c (strsak+avx2) for #c per n where c ≈ 0.293ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 47.000 36.375 35.141 99
|
||
1 35.000 34.625 36.234 96
|
||
2 31.500 18.812 18.992 184
|
||
3 19.667 13.042 13.182 265
|
||
4 30.750 10.281 10.285 339
|
||
7 15.857 8.946 7.551 462
|
||
8 12.125 9.203 7.119 490
|
||
15 10.467 5.475 4.601 758
|
||
16 6.812 5.523 4.798 727
|
||
31 5.387 4.327 3.517 992
|
||
32 4.719 1.645 1.532 2278
|
||
63 5.000 2.403 2.034 1715
|
||
64 2.047 0.779 0.788 4427
|
||
127 2.134 1.194 1.027 3399
|
||
128 1.742 0.444 0.419 8327
|
||
255 0.945 0.594 0.554 6295
|
||
256 0.574 0.271 0.264 13226
|
||
511 0.785 0.362 0.307 11384
|
||
512 0.326 0.178 0.151 23134
|
||
1023 0.288 0.242 0.185 18862
|
||
1024 0.208 0.114 0.107 32565
|
||
2047 0.235 0.127 0.123 28430
|
||
2048 0.127 0.090 0.084 41413
|
||
4095 0.119 0.106 0.099 35116
|
||
4096 0.100 0.081 0.079 44372
|
||
8191 0.092 0.082 0.081 43176
|
||
8192 0.081 0.072 0.071 49419
|
||
16383 0.076 0.072 0.071 48847
|
||
16384 0.071 0.068 0.067 52381
|
||
32767 0.072 0.069 0.068 51154
|
||
32768 0.068 0.066 0.065 53409
|
||
|
||
your tinystrlen()
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 53.000 33.625 33.672 97
|
||
1 33.000 32.125 32.234 101
|
||
2 24.500 19.438 17.711 184
|
||
3 23.667 12.875 11.911 273
|
||
4 13.750 9.281 9.238 352
|
||
7 11.000 6.125 5.801 560
|
||
8 7.625 5.609 5.232 621
|
||
15 11.800 3.825 3.364 966
|
||
16 4.562 3.648 3.173 1024 « optimal
|
||
31 3.710 2.851 2.298 1414
|
||
32 3.031 2.254 2.159 1506 « dropoff
|
||
63 2.683 1.827 1.691 1922
|
||
64 2.078 1.932 1.689 1924
|
||
127 1.630 1.647 1.622 2004
|
||
128 1.727 1.671 1.652 1968
|
||
255 1.392 1.450 1.435 2265
|
||
256 1.473 1.427 1.437 2262
|
||
511 1.325 1.353 1.337 2431
|
||
512 1.408 1.343 1.337 2431
|
||
1023 1.289 1.281 1.287 2525
|
||
1024 1.269 1.295 1.297 2506
|
||
2047 1.269 1.274 1.269 2561
|
||
2048 1.280 1.263 1.281 2538
|
||
4095 1.262 1.270 1.266 2568
|
||
4096 1.270 1.264 1.265 2570
|
||
8191 1.253 1.254 1.254 2592
|
||
8192 1.219 1.224 1.225 2653
|
||
16383 1.225 1.222 1.220 2663
|
||
16384 1.226 1.221 1.222 2659
|
||
32767 1.227 1.224 1.223 2658
|
||
32768 1.220 1.221 1.222 2659
|
||
|
||
glibc strlen for #c per n where c ≈ 0.273ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 3497.000 53.125 42.641 82
|
||
1 69.000 44.875 42.547 82
|
||
2 45.500 24.188 21.852 160
|
||
3 23.000 15.625 14.557 240
|
||
4 22.250 11.406 10.637 328
|
||
7 10.143 6.768 6.230 560
|
||
8 11.125 5.797 5.486 636
|
||
15 5.800 3.142 2.859 1220
|
||
16 7.062 3.070 2.737 1275
|
||
31 2.806 1.585 1.407 2481
|
||
32 3.156 1.574 1.349 2587
|
||
63 2.016 0.895 0.691 5049
|
||
64 1.328 0.744 0.670 5207
|
||
127 1.441 0.521 0.407 8577
|
||
128 0.648 0.454 0.405 8619
|
||
255 0.553 0.286 0.214 16277
|
||
256 0.387 0.235 0.218 15984
|
||
511 0.456 0.151 0.129 27077
|
||
512 0.182 0.134 0.129 27117
|
||
1023 0.171 0.106 0.082 42795
|
||
1024 0.112 0.088 0.082 42741
|
||
2047 0.099 0.069 0.059 59537
|
||
2048 0.072 0.060 0.058 59925
|
||
4095 0.065 0.053 0.047 74122
|
||
4096 0.061 0.048 0.047 74478
|
||
8191 0.048 0.045 0.044 79117
|
||
8192 0.051 0.045 0.044 79181
|
||
16383 0.042 0.040 0.061 57018
|
||
16384 0.069 0.063 0.061 57245
|
||
32767 0.081 0.073 0.068 51426
|
||
32768 0.084 0.072 0.068 51285
|
||
|
||
GCC strlen (-Os REPNZ SCASB) for #c per n where c ≈ 0.293ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 103.000 84.125 88.766 37
|
||
1 81.000 85.125 87.328 37
|
||
2 43.500 44.562 45.508 71
|
||
3 33.000 30.208 30.995 105
|
||
4 24.750 23.156 23.113 141
|
||
7 17.000 13.054 15.355 212
|
||
8 13.375 14.047 13.982 232
|
||
15 9.533 9.258 55.111 59
|
||
16 6.312 6.352 6.364 511
|
||
31 4.032 4.141 4.141 785
|
||
32 3.969 4.059 4.048 803
|
||
63 2.937 2.970 2.995 1086
|
||
64 2.922 2.939 2.956 1100
|
||
127 2.386 2.408 2.403 1353
|
||
128 2.383 2.403 2.401 1354
|
||
255 2.129 2.118 2.124 1530
|
||
256 2.137 2.133 2.130 1526
|
||
511 1.982 1.986 3.351 970
|
||
512 1.982 1.990 1.986 1637
|
||
1023 1.915 1.916 2.587 1257
|
||
1024 1.868 1.867 1.866 1742
|
||
2047 1.835 1.833 1.832 1775
|
||
2048 1.830 1.831 1.832 1775
|
||
4095 1.814 1.814 1.815 1791
|
||
4096 1.810 1.815 1.815 1791
|
||
8191 1.805 1.807 1.806 1800
|
||
8192 1.805 1.806 1.806 1800
|
||
16383 1.803 1.756 1.756 1851
|
||
16384 1.758 1.756 1.756 1851
|
||
32767 1.756 1.754 1.754 1853
|
||
32768 1.756 1.754 1.754 1853
|
||
|
||
Intel Optimz. Manual (SSE4.2) for #c per n where c ≈ 0.273ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 37.000 43.125 34.078 102
|
||
1 33.000 33.875 34.016 103
|
||
2 39.500 17.188 17.555 199
|
||
3 18.333 12.208 12.036 290
|
||
4 30.250 9.344 9.137 382
|
||
7 14.429 5.732 5.766 605
|
||
8 7.875 6.797 5.354 652
|
||
15 10.733 5.825 3.516 993
|
||
16 3.812 2.383 2.325 1501
|
||
31 4.097 2.609 2.079 1678
|
||
32 3.031 1.395 1.349 2587
|
||
63 2.937 1.558 1.079 3235
|
||
64 2.016 0.893 0.690 5056
|
||
127 1.929 0.721 0.607 5745
|
||
128 0.617 0.483 0.428 8147
|
||
255 1.275 0.404 0.411 8486
|
||
256 0.480 0.319 0.299 11681
|
||
511 0.479 0.307 0.288 12127
|
||
512 0.322 0.244 0.232 15013
|
||
1023 0.324 0.224 0.225 15512
|
||
1024 0.245 0.240 0.223 15651
|
||
2047 0.222 0.213 0.206 16938
|
||
2048 0.204 0.194 0.192 18140
|
||
4095 0.204 0.188 0.185 18888
|
||
4096 0.183 0.179 0.179 19446
|
||
8191 0.179 0.176 0.174 20000
|
||
8192 0.174 0.172 0.171 20383
|
||
16383 0.171 0.170 0.169 20604
|
||
16384 0.169 0.169 0.168 20808
|
||
32767 0.213 0.225 0.267 13064
|
||
32768 0.231 0.215 0.220 15852
|
||
|
||
musl libc strlen for #c per n where c ≈ 0.273ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 65.000 36.125 37.984 92
|
||
1 39.000 37.625 37.422 93
|
||
2 41.500 21.938 20.695 169
|
||
3 22.333 17.625 15.859 220
|
||
4 21.250 13.656 12.105 288
|
||
7 22.143 9.018 7.609 459
|
||
8 31.125 7.234 7.346 475
|
||
15 11.267 5.025 4.709 741
|
||
16 9.438 4.039 3.849 907
|
||
31 4.871 3.133 2.488 1402
|
||
32 5.219 2.246 2.039 1712
|
||
63 4.302 1.462 1.407 2479
|
||
64 2.109 1.428 1.155 3023
|
||
127 1.551 1.078 0.879 3971
|
||
128 1.742 0.903 0.760 4591
|
||
255 0.922 0.558 0.605 5764
|
||
256 0.934 0.575 0.537 6495
|
||
511 0.550 0.493 0.455 7674
|
||
512 0.646 0.490 0.426 8183
|
||
1023 0.550 0.439 0.425 8203
|
||
1024 0.472 0.421 0.408 8549
|
||
2047 0.507 0.334 0.373 9360
|
||
2048 0.403 0.426 0.409 8540
|
||
4095 0.391 0.240 0.236 14799
|
||
4096 0.238 0.222 0.221 15766
|
||
8191 0.225 0.223 0.221 15779
|
||
8192 0.225 0.214 0.215 16250
|
||
16383 0.212 0.212 0.210 16595
|
||
16384 0.209 0.210 0.211 16535
|
||
32767 0.214 0.208 0.205 17001
|
||
32768 0.207 0.207 0.291 12002
|
||
|
||
newlib strlen for #c per n where c ≈ 0.273ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 33.000 34.625 34.141 102
|
||
1 33.000 34.125 33.984 103
|
||
2 58.500 18.562 17.508 199
|
||
3 16.333 12.792 12.016 290
|
||
4 19.250 9.219 9.215 379
|
||
7 17.571 6.089 5.685 614
|
||
8 16.625 5.078 5.432 642
|
||
15 8.467 4.042 3.207 1088
|
||
16 3.938 2.773 2.733 1277
|
||
31 3.645 1.673 1.598 2183
|
||
32 3.281 1.527 1.493 2338
|
||
63 2.619 1.042 0.895 3901
|
||
64 1.422 0.928 0.813 4294
|
||
127 0.984 0.718 0.561 6222
|
||
128 1.195 0.591 0.532 6558
|
||
255 0.600 0.404 0.397 8785
|
||
256 0.621 0.429 0.376 9280
|
||
511 0.346 0.311 0.306 11421
|
||
512 0.420 0.308 0.296 11776
|
||
1023 0.284 0.285 0.285 12237
|
||
1024 0.321 0.282 0.280 12456
|
||
2047 0.253 0.252 0.252 13864
|
||
2048 0.260 0.249 0.249 14012
|
||
4095 0.236 0.236 0.236 14811
|
||
4096 0.239 0.235 0.234 14906
|
||
8191 0.233 0.228 0.227 15371
|
||
8192 0.230 0.227 0.227 15397
|
||
16383 0.223 0.224 0.223 15638
|
||
16384 0.223 0.224 0.223 15663
|
||
32767 0.224 0.387 0.225 15527
|
||
32768 0.223 0.222 0.222 15724
|
||
|
||
Agner Fog's strlen (SSE2) for #c per n where c ≈ 0.273ns
|
||
N x1 x8 x64 mBps
|
||
------------------------------------------------------------
|
||
1 59.000 38.375 38.453 91
|
||
1 37.000 38.625 38.234 91
|
||
2 18.500 19.062 19.273 181
|
||
3 13.000 12.792 12.859 271
|
||
4 9.250 9.594 9.660 361
|
||
7 5.286 5.554 5.502 634
|
||
8 4.625 4.703 4.791 728
|
||
15 2.600 2.858 2.622 1331
|
||
16 2.438 2.414 2.421 1442
|
||
31 2.161 1.399 1.290 2706
|
||
32 1.219 1.262 1.250 2793
|
||
63 1.508 0.875 0.693 5038
|
||
64 0.641 0.654 0.655 5328
|
||
127 1.205 0.406 0.379 9200
|
||
128 0.367 0.372 0.369 9463
|
||
255 0.467 0.310 0.235 14835
|
||
256 0.230 0.232 0.232 15034
|
||
511 0.272 0.181 0.159 21918
|
||
512 0.174 0.161 0.158 22148
|
||
1023 0.175 0.134 0.120 29043
|
||
1024 0.140 0.122 0.120 29005
|
||
2047 0.128 0.114 0.112 31205
|
||
2048 0.130 0.113 0.112 31242
|
||
4095 0.105 0.098 0.097 35984
|
||
4096 0.105 0.098 0.097 35973
|
||
8191 0.093 0.090 0.090 38953
|
||
8192 0.094 0.090 0.090 38986
|
||
16383 0.088 0.086 0.086 40648
|
||
16384 0.088 0.086 0.086 40652
|
||
32767 0.088 0.086 0.085 40956
|
||
32768 0.087 0.085 0.085 41114 */
|