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Diffstat (limited to '')
| -rw-r--r-- | src/VBox/Runtime/common/string/strlen.asm | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/strlen.asm b/src/VBox/Runtime/common/string/strlen.asm new file mode 100644 index 00000000..4789c841 --- /dev/null +++ b/src/VBox/Runtime/common/string/strlen.asm @@ -0,0 +1,65 @@ +; $Id: strlen.asm $ +;; @file +; IPRT - No-CRT strlen - AMD64 & X86. +; + +; +; Copyright (C) 2006-2019 Oracle Corporation +; +; This file is part of VirtualBox Open Source Edition (OSE), as +; available from http://www.virtualbox.org. This file is free software; +; you can redistribute it and/or modify it under the terms of the GNU +; General Public License (GPL) as published by the Free Software +; Foundation, in version 2 as it comes in the "COPYING" file of the +; VirtualBox OSE distribution. VirtualBox OSE is distributed in the +; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. +; +; The contents of this file may alternatively be used under the terms +; of the Common Development and Distribution License Version 1.0 +; (CDDL) only, as it comes in the "COPYING.CDDL" file of the +; VirtualBox OSE distribution, in which case the provisions of the +; CDDL are applicable instead of those of the GPL. +; +; You may elect to license modified versions of this file under the +; terms and conditions of either the GPL or the CDDL or both. +; + +%include "iprt/asmdefs.mac" + +BEGINCODE + +;; +; @param psz gcc: rdi msc: rcx x86: [esp+4] wcall: eax +RT_NOCRT_BEGINPROC strlen + cld +%ifdef RT_ARCH_AMD64 + %ifdef ASM_CALL64_MSC + mov r9, rdi ; save rdi + mov rdi, rcx + %endif +%else + mov edx, edi ; save edi + %ifdef ASM_CALL32_WATCOM + mov edi, eax + %else + mov edi, [esp + 4] + %endif +%endif + + ; do the search + mov xCX, -1 + xor eax, eax + repne scasb + + ; found it + neg xCX + lea xAX, [xCX - 2] +%ifdef ASM_CALL64_MSC + mov rdi, r9 +%endif +%ifdef RT_ARCH_X86 + mov edi, edx +%endif + ret +ENDPROC RT_NOCRT(strlen) + |