diff options
Diffstat (limited to 'sysdeps/x86_64')
-rw-r--r-- | sysdeps/x86_64/multiarch/strlen-sse2.S | 2 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/strlen-vec.S | 257 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S | 2 | ||||
-rw-r--r-- | sysdeps/x86_64/strlen.S | 243 |
4 files changed, 262 insertions, 242 deletions
diff --git a/sysdeps/x86_64/multiarch/strlen-sse2.S b/sysdeps/x86_64/multiarch/strlen-sse2.S index 65769f3c2a..f10741c079 100644 --- a/sysdeps/x86_64/multiarch/strlen-sse2.S +++ b/sysdeps/x86_64/multiarch/strlen-sse2.S @@ -20,4 +20,4 @@ # define strlen __strlen_sse2 #endif -#include "../strlen.S" +#include "strlen-vec.S" diff --git a/sysdeps/x86_64/multiarch/strlen-vec.S b/sysdeps/x86_64/multiarch/strlen-vec.S new file mode 100644 index 0000000000..8f660bb9c7 --- /dev/null +++ b/sysdeps/x86_64/multiarch/strlen-vec.S @@ -0,0 +1,257 @@ +/* SSE2 version of strlen and SSE4.1 version of wcslen. + Copyright (C) 2012-2021 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 + <https://www.gnu.org/licenses/>. */ + +#include <sysdep.h> + +#ifdef AS_WCSLEN +# define PMINU pminud +# define PCMPEQ pcmpeqd +# define SHIFT_RETURN shrq $2, %rax +#else +# define PMINU pminub +# define PCMPEQ pcmpeqb +# define SHIFT_RETURN +#endif + +/* Long lived register in strlen(s), strnlen(s, n) are: + + %xmm3 - zero + %rdi - s + %r10 (s+n) & (~(64-1)) + %r11 s+n +*/ + + +.text +ENTRY(strlen) + +/* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx. */ +#define FIND_ZERO \ + PCMPEQ (%rax), %xmm0; \ + PCMPEQ 16(%rax), %xmm1; \ + PCMPEQ 32(%rax), %xmm2; \ + PCMPEQ 48(%rax), %xmm3; \ + pmovmskb %xmm0, %esi; \ + pmovmskb %xmm1, %edx; \ + pmovmskb %xmm2, %r8d; \ + pmovmskb %xmm3, %ecx; \ + salq $16, %rdx; \ + salq $16, %rcx; \ + orq %rsi, %rdx; \ + orq %r8, %rcx; \ + salq $32, %rcx; \ + orq %rcx, %rdx; + +#ifdef AS_STRNLEN +/* Do not read anything when n==0. */ + test %RSI_LP, %RSI_LP + jne L(n_nonzero) + xor %rax, %rax + ret +L(n_nonzero): +# ifdef AS_WCSLEN + shl $2, %RSI_LP +# endif + +/* Initialize long lived registers. */ + + add %RDI_LP, %RSI_LP + mov %RSI_LP, %R10_LP + and $-64, %R10_LP + mov %RSI_LP, %R11_LP +#endif + + pxor %xmm0, %xmm0 + pxor %xmm1, %xmm1 + pxor %xmm2, %xmm2 + pxor %xmm3, %xmm3 + movq %rdi, %rax + movq %rdi, %rcx + andq $4095, %rcx +/* Offsets 4032-4047 will be aligned into 4032 thus fit into page. */ + cmpq $4047, %rcx +/* We cannot unify this branching as it would be ~6 cycles slower. */ + ja L(cross_page) + +#ifdef AS_STRNLEN +/* Test if end is among first 64 bytes. */ +# define STRNLEN_PROLOG \ + mov %r11, %rsi; \ + subq %rax, %rsi; \ + andq $-64, %rax; \ + testq $-64, %rsi; \ + je L(strnlen_ret) +#else +# define STRNLEN_PROLOG andq $-64, %rax; +#endif + +/* Ignore bits in mask that come before start of string. */ +#define PROLOG(lab) \ + movq %rdi, %rcx; \ + xorq %rax, %rcx; \ + STRNLEN_PROLOG; \ + sarq %cl, %rdx; \ + test %rdx, %rdx; \ + je L(lab); \ + bsfq %rdx, %rax; \ + SHIFT_RETURN; \ + ret + +#ifdef AS_STRNLEN + andq $-16, %rax + FIND_ZERO +#else + /* Test first 16 bytes unaligned. */ + movdqu (%rax), %xmm4 + PCMPEQ %xmm0, %xmm4 + pmovmskb %xmm4, %edx + test %edx, %edx + je L(next48_bytes) + bsf %edx, %eax /* If eax is zeroed 16bit bsf can be used. */ + SHIFT_RETURN + ret + +L(next48_bytes): +/* Same as FIND_ZERO except we do not check first 16 bytes. */ + andq $-16, %rax + PCMPEQ 16(%rax), %xmm1 + PCMPEQ 32(%rax), %xmm2 + PCMPEQ 48(%rax), %xmm3 + pmovmskb %xmm1, %edx + pmovmskb %xmm2, %r8d + pmovmskb %xmm3, %ecx + salq $16, %rdx + salq $16, %rcx + orq %r8, %rcx + salq $32, %rcx + orq %rcx, %rdx +#endif + + /* When no zero byte is found xmm1-3 are zero so we do not have to + zero them. */ + PROLOG(loop) + + .p2align 4 +L(cross_page): + andq $-64, %rax + FIND_ZERO + PROLOG(loop_init) + +#ifdef AS_STRNLEN +/* We must do this check to correctly handle strnlen (s, -1). */ +L(strnlen_ret): + bts %rsi, %rdx + sarq %cl, %rdx + test %rdx, %rdx + je L(loop_init) + bsfq %rdx, %rax + SHIFT_RETURN + ret +#endif + .p2align 4 +L(loop_init): + pxor %xmm1, %xmm1 + pxor %xmm2, %xmm2 + pxor %xmm3, %xmm3 +#ifdef AS_STRNLEN + .p2align 4 +L(loop): + + addq $64, %rax + cmpq %rax, %r10 + je L(exit_end) + + movdqa (%rax), %xmm0 + PMINU 16(%rax), %xmm0 + PMINU 32(%rax), %xmm0 + PMINU 48(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 + pmovmskb %xmm0, %edx + testl %edx, %edx + jne L(exit) + jmp L(loop) + + .p2align 4 +L(exit_end): + cmp %rax, %r11 + je L(first) /* Do not read when end is at page boundary. */ + pxor %xmm0, %xmm0 + FIND_ZERO + +L(first): + bts %r11, %rdx + bsfq %rdx, %rdx + addq %rdx, %rax + subq %rdi, %rax + SHIFT_RETURN + ret + + .p2align 4 +L(exit): + pxor %xmm0, %xmm0 + FIND_ZERO + + bsfq %rdx, %rdx + addq %rdx, %rax + subq %rdi, %rax + SHIFT_RETURN + ret + +#else + + /* Main loop. Unrolled twice to improve L2 cache performance on core2. */ + .p2align 4 +L(loop): + + movdqa 64(%rax), %xmm0 + PMINU 80(%rax), %xmm0 + PMINU 96(%rax), %xmm0 + PMINU 112(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 + pmovmskb %xmm0, %edx + testl %edx, %edx + jne L(exit64) + + subq $-128, %rax + + movdqa (%rax), %xmm0 + PMINU 16(%rax), %xmm0 + PMINU 32(%rax), %xmm0 + PMINU 48(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 + pmovmskb %xmm0, %edx + testl %edx, %edx + jne L(exit0) + jmp L(loop) + + .p2align 4 +L(exit64): + addq $64, %rax +L(exit0): + pxor %xmm0, %xmm0 + FIND_ZERO + + bsfq %rdx, %rdx + addq %rdx, %rax + subq %rdi, %rax + SHIFT_RETURN + ret + +#endif + +END(strlen) diff --git a/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S b/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S index a8cab0cb00..5fa51fe07c 100644 --- a/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S +++ b/sysdeps/x86_64/multiarch/wcsnlen-sse4_1.S @@ -2,4 +2,4 @@ #define AS_STRNLEN #define strlen __wcsnlen_sse4_1 -#include "../strlen.S" +#include "strlen-vec.S" diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S index d223ea1700..8422c15cc8 100644 --- a/sysdeps/x86_64/strlen.S +++ b/sysdeps/x86_64/strlen.S @@ -1,5 +1,5 @@ -/* SSE2 version of strlen/wcslen. - Copyright (C) 2012-2021 Free Software Foundation, Inc. +/* SSE2 version of strlen. + Copyright (C) 2021 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 @@ -16,243 +16,6 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#include <sysdep.h> +#include "multiarch/strlen-vec.S" -#ifdef AS_WCSLEN -# define PMINU pminud -# define PCMPEQ pcmpeqd -# define SHIFT_RETURN shrq $2, %rax -#else -# define PMINU pminub -# define PCMPEQ pcmpeqb -# define SHIFT_RETURN -#endif - -/* Long lived register in strlen(s), strnlen(s, n) are: - - %xmm3 - zero - %rdi - s - %r10 (s+n) & (~(64-1)) - %r11 s+n -*/ - - -.text -ENTRY(strlen) - -/* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx. */ -#define FIND_ZERO \ - PCMPEQ (%rax), %xmm0; \ - PCMPEQ 16(%rax), %xmm1; \ - PCMPEQ 32(%rax), %xmm2; \ - PCMPEQ 48(%rax), %xmm3; \ - pmovmskb %xmm0, %esi; \ - pmovmskb %xmm1, %edx; \ - pmovmskb %xmm2, %r8d; \ - pmovmskb %xmm3, %ecx; \ - salq $16, %rdx; \ - salq $16, %rcx; \ - orq %rsi, %rdx; \ - orq %r8, %rcx; \ - salq $32, %rcx; \ - orq %rcx, %rdx; - -#ifdef AS_STRNLEN -/* Do not read anything when n==0. */ - test %RSI_LP, %RSI_LP - jne L(n_nonzero) - xor %rax, %rax - ret -L(n_nonzero): -# ifdef AS_WCSLEN - shl $2, %RSI_LP -# endif - -/* Initialize long lived registers. */ - - add %RDI_LP, %RSI_LP - mov %RSI_LP, %R10_LP - and $-64, %R10_LP - mov %RSI_LP, %R11_LP -#endif - - pxor %xmm0, %xmm0 - pxor %xmm1, %xmm1 - pxor %xmm2, %xmm2 - pxor %xmm3, %xmm3 - movq %rdi, %rax - movq %rdi, %rcx - andq $4095, %rcx -/* Offsets 4032-4047 will be aligned into 4032 thus fit into page. */ - cmpq $4047, %rcx -/* We cannot unify this branching as it would be ~6 cycles slower. */ - ja L(cross_page) - -#ifdef AS_STRNLEN -/* Test if end is among first 64 bytes. */ -# define STRNLEN_PROLOG \ - mov %r11, %rsi; \ - subq %rax, %rsi; \ - andq $-64, %rax; \ - testq $-64, %rsi; \ - je L(strnlen_ret) -#else -# define STRNLEN_PROLOG andq $-64, %rax; -#endif - -/* Ignore bits in mask that come before start of string. */ -#define PROLOG(lab) \ - movq %rdi, %rcx; \ - xorq %rax, %rcx; \ - STRNLEN_PROLOG; \ - sarq %cl, %rdx; \ - test %rdx, %rdx; \ - je L(lab); \ - bsfq %rdx, %rax; \ - SHIFT_RETURN; \ - ret - -#ifdef AS_STRNLEN - andq $-16, %rax - FIND_ZERO -#else - /* Test first 16 bytes unaligned. */ - movdqu (%rax), %xmm4 - PCMPEQ %xmm0, %xmm4 - pmovmskb %xmm4, %edx - test %edx, %edx - je L(next48_bytes) - bsf %edx, %eax /* If eax is zeroed 16bit bsf can be used. */ - SHIFT_RETURN - ret - -L(next48_bytes): -/* Same as FIND_ZERO except we do not check first 16 bytes. */ - andq $-16, %rax - PCMPEQ 16(%rax), %xmm1 - PCMPEQ 32(%rax), %xmm2 - PCMPEQ 48(%rax), %xmm3 - pmovmskb %xmm1, %edx - pmovmskb %xmm2, %r8d - pmovmskb %xmm3, %ecx - salq $16, %rdx - salq $16, %rcx - orq %r8, %rcx - salq $32, %rcx - orq %rcx, %rdx -#endif - - /* When no zero byte is found xmm1-3 are zero so we do not have to - zero them. */ - PROLOG(loop) - - .p2align 4 -L(cross_page): - andq $-64, %rax - FIND_ZERO - PROLOG(loop_init) - -#ifdef AS_STRNLEN -/* We must do this check to correctly handle strnlen (s, -1). */ -L(strnlen_ret): - bts %rsi, %rdx - sarq %cl, %rdx - test %rdx, %rdx - je L(loop_init) - bsfq %rdx, %rax - SHIFT_RETURN - ret -#endif - .p2align 4 -L(loop_init): - pxor %xmm1, %xmm1 - pxor %xmm2, %xmm2 - pxor %xmm3, %xmm3 -#ifdef AS_STRNLEN - .p2align 4 -L(loop): - - addq $64, %rax - cmpq %rax, %r10 - je L(exit_end) - - movdqa (%rax), %xmm0 - PMINU 16(%rax), %xmm0 - PMINU 32(%rax), %xmm0 - PMINU 48(%rax), %xmm0 - PCMPEQ %xmm3, %xmm0 - pmovmskb %xmm0, %edx - testl %edx, %edx - jne L(exit) - jmp L(loop) - - .p2align 4 -L(exit_end): - cmp %rax, %r11 - je L(first) /* Do not read when end is at page boundary. */ - pxor %xmm0, %xmm0 - FIND_ZERO - -L(first): - bts %r11, %rdx - bsfq %rdx, %rdx - addq %rdx, %rax - subq %rdi, %rax - SHIFT_RETURN - ret - - .p2align 4 -L(exit): - pxor %xmm0, %xmm0 - FIND_ZERO - - bsfq %rdx, %rdx - addq %rdx, %rax - subq %rdi, %rax - SHIFT_RETURN - ret - -#else - - /* Main loop. Unrolled twice to improve L2 cache performance on core2. */ - .p2align 4 -L(loop): - - movdqa 64(%rax), %xmm0 - PMINU 80(%rax), %xmm0 - PMINU 96(%rax), %xmm0 - PMINU 112(%rax), %xmm0 - PCMPEQ %xmm3, %xmm0 - pmovmskb %xmm0, %edx - testl %edx, %edx - jne L(exit64) - - subq $-128, %rax - - movdqa (%rax), %xmm0 - PMINU 16(%rax), %xmm0 - PMINU 32(%rax), %xmm0 - PMINU 48(%rax), %xmm0 - PCMPEQ %xmm3, %xmm0 - pmovmskb %xmm0, %edx - testl %edx, %edx - jne L(exit0) - jmp L(loop) - - .p2align 4 -L(exit64): - addq $64, %rax -L(exit0): - pxor %xmm0, %xmm0 - FIND_ZERO - - bsfq %rdx, %rdx - addq %rdx, %rax - subq %rdi, %rax - SHIFT_RETURN - ret - -#endif - -END(strlen) libc_hidden_builtin_def (strlen) |