diff options
Diffstat (limited to 'sysdeps/x86_64/multiarch/strrchr-avx2.S')
| -rw-r--r-- | sysdeps/x86_64/multiarch/strrchr-avx2.S | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/strrchr-avx2.S b/sysdeps/x86_64/multiarch/strrchr-avx2.S new file mode 100644 index 0000000000..4381e6ab3e --- /dev/null +++ b/sysdeps/x86_64/multiarch/strrchr-avx2.S @@ -0,0 +1,235 @@ +/* strrchr/wcsrchr 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 STRRCHR +# define STRRCHR __strrchr_avx2 +# endif + +# ifdef USE_AS_WCSRCHR +# define VPBROADCAST vpbroadcastd +# define VPCMPEQ vpcmpeqd +# else +# define VPBROADCAST vpbroadcastb +# define VPCMPEQ vpcmpeqb +# endif + +# ifndef VZEROUPPER +# define VZEROUPPER vzeroupper +# endif + +# define VEC_SIZE 32 + + .section .text.avx,"ax",@progbits +ENTRY (STRRCHR) + movd %esi, %xmm4 + movl %edi, %ecx + /* Broadcast CHAR to YMM4. */ + VPBROADCAST %xmm4, %ymm4 + vpxor %ymm0, %ymm0, %ymm0 + + /* 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) + + vmovdqu (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %ecx + vpmovmskb %ymm3, %eax + addq $VEC_SIZE, %rdi + + testl %eax, %eax + jnz L(first_vec) + + testl %ecx, %ecx + jnz L(return_null) + + andq $-VEC_SIZE, %rdi + xorl %edx, %edx + jmp L(aligned_loop) + + .p2align 4 +L(first_vec): + /* Check if there is a nul CHAR. */ + testl %ecx, %ecx + jnz L(char_and_nul_in_first_vec) + + /* Remember the match and keep searching. */ + movl %eax, %edx + movq %rdi, %rsi + andq $-VEC_SIZE, %rdi + jmp L(aligned_loop) + + .p2align 4 +L(cros_page_boundary): + andl $(VEC_SIZE - 1), %ecx + andq $-VEC_SIZE, %rdi + vmovdqa (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %edx + vpmovmskb %ymm3, %eax + shrl %cl, %edx + shrl %cl, %eax + addq $VEC_SIZE, %rdi + + /* Check if there is a CHAR. */ + testl %eax, %eax + jnz L(found_char) + + testl %edx, %edx + jnz L(return_null) + + jmp L(aligned_loop) + + .p2align 4 +L(found_char): + testl %edx, %edx + jnz L(char_and_nul) + + /* Remember the match and keep searching. */ + movl %eax, %edx + leaq (%rdi, %rcx), %rsi + + .p2align 4 +L(aligned_loop): + vmovdqa (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + addq $VEC_SIZE, %rdi + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %ecx + vpmovmskb %ymm3, %eax + orl %eax, %ecx + jnz L(char_nor_null) + + vmovdqa (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + add $VEC_SIZE, %rdi + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %ecx + vpmovmskb %ymm3, %eax + orl %eax, %ecx + jnz L(char_nor_null) + + vmovdqa (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + addq $VEC_SIZE, %rdi + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %ecx + vpmovmskb %ymm3, %eax + orl %eax, %ecx + jnz L(char_nor_null) + + vmovdqa (%rdi), %ymm1 + VPCMPEQ %ymm1, %ymm0, %ymm2 + addq $VEC_SIZE, %rdi + VPCMPEQ %ymm1, %ymm4, %ymm3 + vpmovmskb %ymm2, %ecx + vpmovmskb %ymm3, %eax + orl %eax, %ecx + jz L(aligned_loop) + + .p2align 4 +L(char_nor_null): + /* Find a CHAR or a nul CHAR in a loop. */ + testl %eax, %eax + jnz L(match) +L(return_value): + testl %edx, %edx + jz L(return_null) + movl %edx, %eax + movq %rsi, %rdi + +# ifdef USE_AS_WCSRCHR + /* Keep the first bit for each matching CHAR for bsr. */ + andl $0x11111111, %eax +# endif + bsrl %eax, %eax + leaq -VEC_SIZE(%rdi, %rax), %rax + VZEROUPPER + ret + + .p2align 4 +L(match): + /* Find a CHAR. Check if there is a nul CHAR. */ + vpmovmskb %ymm2, %ecx + testl %ecx, %ecx + jnz L(find_nul) + + /* Remember the match and keep searching. */ + movl %eax, %edx + movq %rdi, %rsi + jmp L(aligned_loop) + + .p2align 4 +L(find_nul): +# ifdef USE_AS_WCSRCHR + /* Keep the first bit for each matching CHAR for bsr. */ + andl $0x11111111, %ecx + andl $0x11111111, %eax +# endif + /* Mask out any matching bits after the nul CHAR. */ + movl %ecx, %r8d + subl $1, %r8d + xorl %ecx, %r8d + andl %r8d, %eax + testl %eax, %eax + /* If there is no CHAR here, return the remembered one. */ + jz L(return_value) + bsrl %eax, %eax + leaq -VEC_SIZE(%rdi, %rax), %rax + VZEROUPPER + ret + + .p2align 4 +L(char_and_nul): + /* Find both a CHAR and a nul CHAR. */ + addq %rcx, %rdi + movl %edx, %ecx +L(char_and_nul_in_first_vec): +# ifdef USE_AS_WCSRCHR + /* Keep the first bit for each matching CHAR for bsr. */ + andl $0x11111111, %ecx + andl $0x11111111, %eax +# endif + /* Mask out any matching bits after the nul CHAR. */ + movl %ecx, %r8d + subl $1, %r8d + xorl %ecx, %r8d + andl %r8d, %eax + testl %eax, %eax + /* Return null pointer if the nul CHAR comes first. */ + jz L(return_null) + bsrl %eax, %eax + leaq -VEC_SIZE(%rdi, %rax), %rax + VZEROUPPER + ret + + .p2align 4 +L(return_null): + xorl %eax, %eax + VZEROUPPER + ret + +END (STRRCHR) +#endif |