diff options
Diffstat (limited to 'sysdeps/x86_64/multiarch/strlen-avx2.S')
| -rw-r--r-- | sysdeps/x86_64/multiarch/strlen-avx2.S | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/strlen-avx2.S b/sysdeps/x86_64/multiarch/strlen-avx2.S new file mode 100644 index 0000000000..fb2418cddc --- /dev/null +++ b/sysdeps/x86_64/multiarch/strlen-avx2.S @@ -0,0 +1,393 @@ +/* strlen/strnlen/wcslen/wcsnlen optimized with AVX2. + Copyright (C) 2017-2018 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/>. */ + +#if IS_IN (libc) + +# include <sysdep.h> + +# ifndef STRLEN +# define STRLEN __strlen_avx2 +# endif + +# ifdef USE_AS_WCSLEN +# define VPCMPEQ vpcmpeqd +# define VPMINU vpminud +# else +# define VPCMPEQ vpcmpeqb +# define VPMINU vpminub +# endif + +# ifndef VZEROUPPER +# define VZEROUPPER vzeroupper +# endif + +# define VEC_SIZE 32 + + .section .text.avx,"ax",@progbits +ENTRY (STRLEN) +# ifdef USE_AS_STRNLEN + /* Check for zero length. */ + testq %rsi, %rsi + jz L(zero) +# ifdef USE_AS_WCSLEN + shl $2, %rsi +# endif + movq %rsi, %r8 +# endif + movl %edi, %ecx + movq %rdi, %rdx + vpxor %xmm0, %xmm0, %xmm0 + + /* Check if we may cross page boundary with one vector load. */ + andl $(2 * VEC_SIZE - 1), %ecx + cmpl $VEC_SIZE, %ecx + ja L(cros_page_boundary) + + /* Check the first VEC_SIZE bytes. */ + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + +# ifdef USE_AS_STRNLEN + jnz L(first_vec_x0_check) + /* Adjust length and check the end of data. */ + subq $VEC_SIZE, %rsi + jbe L(max) +# else + jnz L(first_vec_x0) +# endif + + /* Align data for aligned loads in the loop. */ + addq $VEC_SIZE, %rdi + andl $(VEC_SIZE - 1), %ecx + andq $-VEC_SIZE, %rdi + +# ifdef USE_AS_STRNLEN + /* Adjust length. */ + addq %rcx, %rsi + + subq $(VEC_SIZE * 4), %rsi + jbe L(last_4x_vec_or_less) +# endif + jmp L(more_4x_vec) + + .p2align 4 +L(cros_page_boundary): + andl $(VEC_SIZE - 1), %ecx + andq $-VEC_SIZE, %rdi + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + /* Remove the leading bytes. */ + sarl %cl, %eax + testl %eax, %eax + jz L(aligned_more) + tzcntl %eax, %eax +# ifdef USE_AS_STRNLEN + /* Check the end of data. */ + cmpq %rax, %rsi + jbe L(max) +# endif + addq %rdi, %rax + addq %rcx, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(aligned_more): +# ifdef USE_AS_STRNLEN + /* "rcx" is less than VEC_SIZE. Calculate "rdx + rcx - VEC_SIZE" + with "rdx - (VEC_SIZE - rcx)" instead of "(rdx + rcx) - VEC_SIZE" + to void possible addition overflow. */ + negq %rcx + addq $VEC_SIZE, %rcx + + /* Check the end of data. */ + subq %rcx, %rsi + jbe L(max) +# endif + + addq $VEC_SIZE, %rdi + +# ifdef USE_AS_STRNLEN + subq $(VEC_SIZE * 4), %rsi + jbe L(last_4x_vec_or_less) +# endif + +L(more_4x_vec): + /* Check the first 4 * VEC_SIZE. Only one VEC_SIZE at a time + since data is only aligned to VEC_SIZE. */ + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + + VPCMPEQ VEC_SIZE(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x1) + + VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x2) + + VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x3) + + addq $(VEC_SIZE * 4), %rdi + +# ifdef USE_AS_STRNLEN + subq $(VEC_SIZE * 4), %rsi + jbe L(last_4x_vec_or_less) +# endif + + /* Align data to 4 * VEC_SIZE. */ + movq %rdi, %rcx + andl $(4 * VEC_SIZE - 1), %ecx + andq $-(4 * VEC_SIZE), %rdi + +# ifdef USE_AS_STRNLEN + /* Adjust length. */ + addq %rcx, %rsi +# endif + + .p2align 4 +L(loop_4x_vec): + /* Compare 4 * VEC at a time forward. */ + vmovdqa (%rdi), %ymm1 + vmovdqa VEC_SIZE(%rdi), %ymm2 + vmovdqa (VEC_SIZE * 2)(%rdi), %ymm3 + vmovdqa (VEC_SIZE * 3)(%rdi), %ymm4 + VPMINU %ymm1, %ymm2, %ymm5 + VPMINU %ymm3, %ymm4, %ymm6 + VPMINU %ymm5, %ymm6, %ymm5 + + VPCMPEQ %ymm5, %ymm0, %ymm5 + vpmovmskb %ymm5, %eax + testl %eax, %eax + jnz L(4x_vec_end) + + addq $(VEC_SIZE * 4), %rdi + +# ifndef USE_AS_STRNLEN + jmp L(loop_4x_vec) +# else + subq $(VEC_SIZE * 4), %rsi + ja L(loop_4x_vec) + +L(last_4x_vec_or_less): + /* Less than 4 * VEC and aligned to VEC_SIZE. */ + addl $(VEC_SIZE * 2), %esi + jle L(last_2x_vec) + + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + + VPCMPEQ VEC_SIZE(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x1) + + VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + + jnz L(first_vec_x2_check) + subl $VEC_SIZE, %esi + jle L(max) + + VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + + jnz L(first_vec_x3_check) + movq %r8, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(last_2x_vec): + addl $(VEC_SIZE * 2), %esi + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + + jnz L(first_vec_x0_check) + subl $VEC_SIZE, %esi + jle L(max) + + VPCMPEQ VEC_SIZE(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x1_check) + movq %r8, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x0_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rsi + jbe L(max) + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x1_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rsi + jbe L(max) + addq $VEC_SIZE, %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x2_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rsi + jbe L(max) + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x3_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rsi + jbe L(max) + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(max): + movq %r8, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(zero): + xorl %eax, %eax + ret +# endif + + .p2align 4 +L(first_vec_x0): + tzcntl %eax, %eax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x1): + tzcntl %eax, %eax + addq $VEC_SIZE, %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x2): + tzcntl %eax, %eax + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + + .p2align 4 +L(4x_vec_end): + VPCMPEQ %ymm1, %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + VPCMPEQ %ymm2, %ymm0, %ymm2 + vpmovmskb %ymm2, %eax + testl %eax, %eax + jnz L(first_vec_x1) + VPCMPEQ %ymm3, %ymm0, %ymm3 + vpmovmskb %ymm3, %eax + testl %eax, %eax + jnz L(first_vec_x2) + VPCMPEQ %ymm4, %ymm0, %ymm4 + vpmovmskb %ymm4, %eax +L(first_vec_x3): + tzcntl %eax, %eax + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax + subq %rdx, %rax +# ifdef USE_AS_WCSLEN + shrq $2, %rax +# endif + VZEROUPPER + ret + +END (STRLEN) +#endif |