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/*
Copyright 2022 Gabriel Jensen.
This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
If a copy of the MPL was not distributed with this file, You can obtain one at https://mozilla.org/MPL/2.0/.
*/
#include <zap/priv.h>
.globl zap_fndbyte
zap_fndbyte:
/*
void const * ptr
zap_sz num
unsigned char byte
*/
#if defined(__amd64__)
# rax: Address of the current element.
# rdi: Address of the first element.
# rsi: Address of the element after the last element.
# rdx: Byte value.
# rcx: Current byte.
movq %rdi,%rax
addq %rdi,%rsi
# Iterate over the array:
.loop:
# Check if we have reached the end of the array:
cmpq %rax,%rsi
je .nfnd
# Check if we have found the byte value:
movb (%rax),%cl
cmpb %cl,%dl
je .fnd
# Continue to the next byte:
incq %rax
jmp .loop
# Found:
.fnd:
subq %rdi,%rax
ret
# Not found:
.nfnd:
movq $0xFFFFFFFFFFFFFFFF,%rax
ret
#endif
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