1 files changed, 142 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/strchr.asm b/src/VBox/Runtime/common/string/strchr.asm
new file mode 100644
index 00000000..fa6eb515
--- /dev/null
+++ b/src/VBox/Runtime/common/string/strchr.asm
@@ -0,0 +1,142 @@
+; $Id: strchr.asm $
+;; @file
+; IPRT - No-CRT strchr - AMD64 & X86.
+;
+
+;
+; Copyright (C) 2006-2020 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
+; @param    ch      gcc: esi  msc: edx  x86:[esp+8]  wcall: edx
+RT_NOCRT_BEGINPROC strchr
+        cld
+
+        ; check for ch == 0 and setup normal strchr.
+%ifdef RT_ARCH_AMD64
+ %ifdef ASM_CALL64_MSC
+        or      dl, dl
+        jz near .strlen
+        mov     r9, rsi                 ; save rsi
+        mov     rsi, rcx
+ %else
+        or      sil, sil
+        jz near .strlen
+        mov     edx, esi
+        mov     rsi, rdi
+ %endif
+%else
+ %ifndef ASM_CALL32_WATCOM
+        mov     edx, [esp + 8]
+ %endif
+        or      dl, dl
+        jz near .strlen
+        mov     ecx, esi                ; save esi
+ %ifdef ASM_CALL32_WATCOM
+        mov     esi, eax
+ %else
+        mov     esi, [esp + 4]
+ %endif
+%endif
+
+        ; do the search
+.next:
+        lodsb
+        cmp     al, dl
+        je      .found
+        test    al, al
+        jz      .not_found
+
+        lodsb
+        cmp     al, dl
+        je      .found
+        test    al, al
+        jz      .not_found
+
+        lodsb
+        cmp     al, dl
+        je      .found
+        test    al, al
+        jz      .not_found
+
+        lodsb
+        cmp     al, dl
+        je      .found
+        test    al, al
+        jz      .not_found
+        jmp .next
+
+.found:
+        lea     xAX, [xSI - 1]
+%ifdef ASM_CALL64_MSC
+        mov     rsi, r9
+%endif
+%ifdef RT_ARCH_X86
+        mov     esi, ecx
+%endif
+        ret
+
+.not_found:
+%ifdef ASM_CALL64_MSC
+        mov     rsi, r9
+%endif
+%ifdef RT_ARCH_X86
+        mov     esi, ecx
+%endif
+        xor     eax, eax
+        ret
+
+;
+; Special case: strchr(str, '\0');
+;
+align 16
+.strlen:
+%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
+        mov     xCX, -1
+        xor     eax, eax
+        repne scasb
+
+        lea     xAX, [xDI - 1]
+%ifdef ASM_CALL64_MSC
+        mov     rdi, r9
+%endif
+%ifdef RT_ARCH_X86
+        mov     edi, edx
+%endif
+        ret
+ENDPROC RT_NOCRT(strchr)
+