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/* strlen used for begining of str{n}cat using AVX2.
Copyright (C) 2011-2023 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/>. */
/* NOTE: This file is meant to be included by strcat-avx2 or
strncat-avx2 and does not standalone. Before including %rdi
must be saved in %rax. */
/* Simple strlen implementation that ends at
L(strcat_strlen_done). */
movq %rdi, %r8
andq $(VEC_SIZE * -1), %r8
VPCMPEQ (%r8), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
shrxl %edi, %ecx, %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v0)
VPCMPEQ VEC_SIZE(%r8), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
leaq (VEC_SIZE)(%r8), %rdi
testl %ecx, %ecx
jnz L(bsf_and_done_v0)
VPCMPEQ (VEC_SIZE * 1)(%rdi), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v1)
VPCMPEQ (VEC_SIZE * 2)(%rdi), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v2)
VPCMPEQ (VEC_SIZE * 3)(%rdi), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v3)
orq $(VEC_SIZE * 4 - 1), %rdi
.p2align 4,, 8
L(loop_2x_vec):
VMOVA (VEC_SIZE * 0 + 1)(%rdi), %VMM(0)
VPMIN (VEC_SIZE * 1 + 1)(%rdi), %VMM(0), %VMM(1)
VMOVA (VEC_SIZE * 2 + 1)(%rdi), %VMM(2)
VPMIN (VEC_SIZE * 3 + 1)(%rdi), %VMM(2), %VMM(3)
VPMIN %VMM(1), %VMM(3), %VMM(3)
VPCMPEQ %VMM(3), %VZERO, %VMM(3)
vpmovmskb %VMM(3), %r8d
subq $(VEC_SIZE * -4), %rdi
testl %r8d, %r8d
jz L(loop_2x_vec)
addq $(VEC_SIZE * -4 + 1), %rdi
VPCMPEQ %VMM(0), %VZERO, %VMM(0)
vpmovmskb %VMM(0), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v0)
VPCMPEQ %VMM(1), %VZERO, %VMM(1)
vpmovmskb %VMM(1), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v1)
VPCMPEQ %VMM(2), %VZERO, %VMM(2)
vpmovmskb %VMM(2), %ecx
testl %ecx, %ecx
jnz L(bsf_and_done_v2)
movl %r8d, %ecx
L(bsf_and_done_v3):
addq $VEC_SIZE, %rdi
L(bsf_and_done_v2):
bsfl %ecx, %ecx
leaq (VEC_SIZE * 2)(%rdi, %rcx), %rdi
jmp L(strcat_strlen_done)
.p2align 4,, 4
L(bsf_and_done_v1):
addq $VEC_SIZE, %rdi
L(bsf_and_done_v0):
bsfl %ecx, %ecx
addq %rcx, %rdi
L(strcat_strlen_done):
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