diff options
Diffstat (limited to 'sysdeps/x86_64/multiarch/memchr-avx2.S')
| -rw-r--r-- | sysdeps/x86_64/multiarch/memchr-avx2.S | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/memchr-avx2.S b/sysdeps/x86_64/multiarch/memchr-avx2.S new file mode 100644 index 0000000000..5f5e772554 --- /dev/null +++ b/sysdeps/x86_64/multiarch/memchr-avx2.S @@ -0,0 +1,340 @@ +/* memchr/wmemchr 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 MEMCHR +# define MEMCHR __memchr_avx2 +# endif + +# ifdef USE_AS_WMEMCHR +# define VPCMPEQ vpcmpeqd +# else +# define VPCMPEQ vpcmpeqb +# endif + +# ifndef VZEROUPPER +# define VZEROUPPER vzeroupper +# endif + +# define VEC_SIZE 32 + + .section .text.avx,"ax",@progbits +ENTRY (MEMCHR) +# ifndef USE_AS_RAWMEMCHR + /* Check for zero length. */ + testq %rdx, %rdx + jz L(null) +# endif + movl %edi, %ecx + /* Broadcast CHAR to YMM0. */ + vmovd %esi, %xmm0 +# ifdef USE_AS_WMEMCHR + shl $2, %rdx + vpbroadcastd %xmm0, %ymm0 +# else + vpbroadcastb %xmm0, %ymm0 +# endif + /* 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 + +# ifndef USE_AS_RAWMEMCHR + jnz L(first_vec_x0_check) + /* Adjust length and check the end of data. */ + subq $VEC_SIZE, %rdx + jbe L(zero) +# 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 + +# ifndef USE_AS_RAWMEMCHR + /* Adjust length. */ + addq %rcx, %rdx + + subq $(VEC_SIZE * 4), %rdx + 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 +# ifndef USE_AS_RAWMEMCHR + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) +# endif + addq %rdi, %rax + addq %rcx, %rax + VZEROUPPER + ret + + .p2align 4 +L(aligned_more): +# ifndef USE_AS_RAWMEMCHR + /* 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, %rdx + jbe L(zero) +# endif + + addq $VEC_SIZE, %rdi + +# ifndef USE_AS_RAWMEMCHR + subq $(VEC_SIZE * 4), %rdx + 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 + +# ifndef USE_AS_RAWMEMCHR + subq $(VEC_SIZE * 4), %rdx + 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 + +# ifndef USE_AS_RAWMEMCHR + /* Adjust length. */ + addq %rcx, %rdx +# endif + + .p2align 4 +L(loop_4x_vec): + /* Compare 4 * VEC at a time forward. */ + VPCMPEQ (%rdi), %ymm0, %ymm1 + VPCMPEQ VEC_SIZE(%rdi), %ymm0, %ymm2 + VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm0, %ymm3 + VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm0, %ymm4 + + vpor %ymm1, %ymm2, %ymm5 + vpor %ymm3, %ymm4, %ymm6 + vpor %ymm5, %ymm6, %ymm5 + + vpmovmskb %ymm5, %eax + testl %eax, %eax + jnz L(4x_vec_end) + + addq $(VEC_SIZE * 4), %rdi + +# ifdef USE_AS_RAWMEMCHR + jmp L(loop_4x_vec) +# else + subq $(VEC_SIZE * 4), %rdx + ja L(loop_4x_vec) + +L(last_4x_vec_or_less): + /* Less than 4 * VEC and aligned to VEC_SIZE. */ + addl $(VEC_SIZE * 2), %edx + 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, %edx + jle L(zero) + + VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + + jnz L(first_vec_x3_check) + xorl %eax, %eax + VZEROUPPER + ret + + .p2align 4 +L(last_2x_vec): + addl $(VEC_SIZE * 2), %edx + VPCMPEQ (%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + + jnz L(first_vec_x0_check) + subl $VEC_SIZE, %edx + jle L(zero) + + VPCMPEQ VEC_SIZE(%rdi), %ymm0, %ymm1 + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x1_check) + xorl %eax, %eax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x0_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x1_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $VEC_SIZE, %rax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x2_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x3_check): + tzcntl %eax, %eax + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(zero): + VZEROUPPER +L(null): + xorl %eax, %eax + ret +# endif + + .p2align 4 +L(first_vec_x0): + tzcntl %eax, %eax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x1): + tzcntl %eax, %eax + addq $VEC_SIZE, %rax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(first_vec_x2): + tzcntl %eax, %eax + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax + VZEROUPPER + ret + + .p2align 4 +L(4x_vec_end): + vpmovmskb %ymm1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + vpmovmskb %ymm2, %eax + testl %eax, %eax + jnz L(first_vec_x1) + vpmovmskb %ymm3, %eax + testl %eax, %eax + jnz L(first_vec_x2) + vpmovmskb %ymm4, %eax + testl %eax, %eax +L(first_vec_x3): + tzcntl %eax, %eax + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax + VZEROUPPER + ret + +END (MEMCHR) +#endif |