| 1 | ; $Id: strlen.asm 98103 2023-01-17 14:15:46Z vboxsync $
|
|---|
| 2 | ;; @file
|
|---|
| 3 | ; IPRT - No-CRT strlen - AMD64 & X86.
|
|---|
| 4 | ;
|
|---|
| 5 |
|
|---|
| 6 | ;
|
|---|
| 7 | ; Copyright (C) 2006-2023 Oracle and/or its affiliates.
|
|---|
| 8 | ;
|
|---|
| 9 | ; This file is part of VirtualBox base platform packages, as
|
|---|
| 10 | ; available from https://www.virtualbox.org.
|
|---|
| 11 | ;
|
|---|
| 12 | ; This program is free software; you can redistribute it and/or
|
|---|
| 13 | ; modify it under the terms of the GNU General Public License
|
|---|
| 14 | ; as published by the Free Software Foundation, in version 3 of the
|
|---|
| 15 | ; License.
|
|---|
| 16 | ;
|
|---|
| 17 | ; This program is distributed in the hope that it will be useful, but
|
|---|
| 18 | ; WITHOUT ANY WARRANTY; without even the implied warranty of
|
|---|
| 19 | ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|---|
| 20 | ; General Public License for more details.
|
|---|
| 21 | ;
|
|---|
| 22 | ; You should have received a copy of the GNU General Public License
|
|---|
| 23 | ; along with this program; if not, see <https://www.gnu.org/licenses>.
|
|---|
| 24 | ;
|
|---|
| 25 | ; The contents of this file may alternatively be used under the terms
|
|---|
| 26 | ; of the Common Development and Distribution License Version 1.0
|
|---|
| 27 | ; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
|
|---|
| 28 | ; in the VirtualBox distribution, in which case the provisions of the
|
|---|
| 29 | ; CDDL are applicable instead of those of the GPL.
|
|---|
| 30 | ;
|
|---|
| 31 | ; You may elect to license modified versions of this file under the
|
|---|
| 32 | ; terms and conditions of either the GPL or the CDDL or both.
|
|---|
| 33 | ;
|
|---|
| 34 | ; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
|
|---|
| 35 | ;
|
|---|
| 36 |
|
|---|
| 37 | %include "iprt/asmdefs.mac"
|
|---|
| 38 |
|
|---|
| 39 | BEGINCODE
|
|---|
| 40 |
|
|---|
| 41 | ;;
|
|---|
| 42 | ; @param psz gcc: rdi msc: rcx x86: [esp+4] wcall: eax
|
|---|
| 43 | RT_NOCRT_BEGINPROC strlen
|
|---|
| 44 | cld
|
|---|
| 45 | %ifdef RT_ARCH_AMD64
|
|---|
| 46 | %ifdef ASM_CALL64_MSC
|
|---|
| 47 | mov r9, rdi ; save rdi
|
|---|
| 48 | mov rdi, rcx
|
|---|
| 49 | %endif
|
|---|
| 50 | %else
|
|---|
| 51 | mov edx, edi ; save edi
|
|---|
| 52 | %ifdef ASM_CALL32_WATCOM
|
|---|
| 53 | mov edi, eax
|
|---|
| 54 | %else
|
|---|
| 55 | mov edi, [esp + 4]
|
|---|
| 56 | %endif
|
|---|
| 57 | %endif
|
|---|
| 58 |
|
|---|
| 59 | ; do the search
|
|---|
| 60 | mov xCX, -1
|
|---|
| 61 | xor eax, eax
|
|---|
| 62 | repne scasb
|
|---|
| 63 |
|
|---|
| 64 | ; found it
|
|---|
| 65 | neg xCX
|
|---|
| 66 | lea xAX, [xCX - 2]
|
|---|
| 67 | %ifdef ASM_CALL64_MSC
|
|---|
| 68 | mov rdi, r9
|
|---|
| 69 | %endif
|
|---|
| 70 | %ifdef RT_ARCH_X86
|
|---|
| 71 | mov edi, edx
|
|---|
| 72 | %endif
|
|---|
| 73 | ret
|
|---|
| 74 | ENDPROC RT_NOCRT(strlen)
|
|---|
| 75 |
|
|---|
