diff options
Diffstat (limited to 'src/VBox/Runtime/common/string/memchr.asm')
| -rw-r--r-- | src/VBox/Runtime/common/string/memchr.asm | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/memchr.asm b/src/VBox/Runtime/common/string/memchr.asm new file mode 100644 index 00000000..7bace6b6 --- /dev/null +++ b/src/VBox/Runtime/common/string/memchr.asm @@ -0,0 +1,103 @@ +; $Id: memchr.asm $ +;; @file +; IPRT - No-CRT memchr - AMD64 & X86. +; + +; +; Copyright (C) 2006-2023 Oracle and/or its affiliates. +; +; This file is part of VirtualBox base platform packages, as +; available from https://www.virtualbox.org. +; +; This program is free software; you can redistribute it and/or +; modify it under the terms of the GNU General Public License +; as published by the Free Software Foundation, in version 3 of the +; License. +; +; This program 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 +; General Public License for more details. +; +; You should have received a copy of the GNU General Public License +; along with this program; if not, see <https://www.gnu.org/licenses>. +; +; The contents of this file may alternatively be used under the terms +; of the Common Development and Distribution License Version 1.0 +; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included +; in the VirtualBox 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. +; +; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 +; + +%include "iprt/asmdefs.mac" + +BEGINCODE + +;; +; @param pv gcc: rdi msc: ecx x86:[esp+4] wcall: eax +; @param ch gcc: esi msc: edx x86:[esp+8] wcall: edx +; @param cb gcc: rdx msc: r8 x86:[esp+0ch] wcall: ebx +RT_NOCRT_BEGINPROC memchr + cld +%ifdef RT_ARCH_AMD64 + %ifdef ASM_CALL64_MSC + or r8, r8 + jz .not_found_early + + mov r9, rdi ; save rdi + mov eax, edx + mov rdi, rcx + mov rcx, r8 + %else + mov rcx, rdx + jrcxz .not_found_early + + mov eax, esi + %endif + +%else + %ifdef ASM_CALL32_WATCOM + mov ecx, ebx + jecxz .not_found_early + xchg eax, edx + xchg edi, edx ; load and save edi. + %else + mov ecx, [esp + 0ch] + jecxz .not_found_early + mov edx, edi ; save edi + mov eax, [esp + 8] + mov edi, [esp + 4] + %endif +%endif + + ; do the search + repne scasb + jne .not_found + + ; found it + lea xAX, [xDI - 1] +%ifdef ASM_CALL64_MSC + mov rdi, r9 +%endif +%ifdef RT_ARCH_X86 + mov edi, edx +%endif + ret + +.not_found: +%ifdef ASM_CALL64_MSC + mov rdi, r9 +%endif +%ifdef RT_ARCH_X86 + mov edi, edx +%endif +.not_found_early: + xor eax, eax + ret +ENDPROC RT_NOCRT(memchr) + |