Changeset 7185 in vbox for trunk/src/VBox/Runtime

Timestamp:

Feb 27, 2008 6:34:30 PM (17 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

28485

Message:

no-crt memmove implementation.

Location:

trunk/src/VBox/Runtime/common/string

Files:

• memmove.asm (copied) (copied from trunk/src/VBox/Runtime/common/string/memcpy.asm ) (5 diffs)
• memmove_alias.c (copied) (copied from trunk/src/VBox/Runtime/common/string/memcpy_alias.c ) (2 diffs)

trunk/src/VBox/Runtime/common/string/memmove.asm

@@ -1 +1 @@
 ; $Id$
 ;; @file
-; innotek Portable Runtime - No-CRT memcpy - AMD64 & X86.
+; innotek Portable Runtime - No-CRT memmove - AMD64 & X86.
 ;
 
 ;
-; Copyright (C) 2006-2007 innotek GmbH
+; Copyright (C) 2006-2008 innotek GmbH
 ;
 ; This file is part of VirtualBox Open Source Edition (OSE), as
@@ -33 +33 @@
 ; @param    pvSrc   gcc: rsi  msc: rdx  x86:[esp+8]
 ; @param    cb      gcc: rdx  msc: r8   x86:[esp+0ch]
-BEGINPROC RT_NOCRT(memcpy)
-        cld
-
-        ; Do the bulk of the work.
+BEGINPROC RT_NOCRT(memmove)
+        ; Prolog.
 %ifdef RT_ARCH_AMD64
  %ifdef ASM_CALL64_MSC
@@ -49 +47 @@
  %endif
         mov     rax, rdi                ; save the return value
+%else
+        push    edi
+        push    esi
+        mov     edi, [esp + 04h + 8]
+        mov     esi, [esp + 08h + 8]
+        mov     ecx, [esp + 0ch + 8]
+        mov     edx, ecx
+        mov     eax, edi                ; save the return value
+%endif
+
+        ;
+        ; Decide which direction to perform the copy in.
+        ;
+        cmp     xDI, xSI
+        jb      .forward
+
+        ;
+        ; Copy forward.
+        ;
+.forward:
+        cld
+%ifdef RT_ARCH_AMD64
         shr     rcx, 3
         rep movsq
 %else
-        push    edi
-        push    esi
-
-        mov     ecx, [esp + 0ch + 8]
-        mov     edi, [esp + 04h + 8]
-        mov     esi, [esp + 08h + 8]
-        mov     edx, ecx
-        mov     eax, edi                ; save the return value
         shr     ecx, 2
         rep movsd
@@ -67 +79 @@
 %ifdef RT_ARCH_AMD64
         test    dl, 4
-        jz      .dont_move_dword
+        jz      .forward_dont_move_dword
         movsd
 %endif
-.dont_move_dword:
+.forward_dont_move_dword:
         test    dl, 2
-        jz      .dont_move_word
+        jz      .forward_dont_move_word
         movsw
-.dont_move_word:
+.forward_dont_move_word:
         test    dl, 1
-        jz      .dont_move_byte
+        jz      .forward_dont_move_byte
         movsb
-.dont_move_byte:
+.forward_dont_move_byte:
 
+        ;
+        ; The epilog.
+        ;
+.epilog:
 %ifdef RT_ARCH_AMD64
  %ifdef ASM_CALL64_MSC
@@ -90 +106 @@
 %endif
         ret
-ENDPROC RT_NOCRT(memcpy)
 
+
+        ;
+        ; Copy backward.
+        ;
+ALIGNCODE(16)
+.backward:
+        std
+        add     xDI, xCX
+        add     xSI, xCX
+%ifdef RT_ARCH_AMD64
+        shr     rcx, 3
+        rep movsq
+%else
+        shr     ecx, 2
+        rep movsd
+%endif
+
+        ; The remaining bytes.
+%ifdef RT_ARCH_AMD64
+        test    dl, 4
+        jz      .backward_dont_move_dword
+        movsd
+%endif
+.backward_dont_move_dword:
+        test    dl, 2
+        jz      .backward_dont_move_word
+        movsw
+.backward_dont_move_word:
+        test    dl, 1
+        jz      .backward_dont_move_byte
+        movsb
+.backward_dont_move_byte:
+
+        cld
+        jmp .epilog
+ENDPROC RT_NOCRT(memmove)
+

trunk/src/VBox/Runtime/common/string/memmove_alias.c

@@ -1 +1 @@
 /* $Id$ */
 /** @file
- * innotek Portable Runtime - No-CRT memcpy() alias for gcc.
+ * innotek Portable Runtime - No-CRT memmove() alias for gcc.
  */
 
 /*
- * Copyright (C) 2006-2007 innotek GmbH
+ * Copyright (C) 2006-2008 innotek GmbH
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
@@ -30 +30 @@
 *******************************************************************************/
 #include <iprt/nocrt/string.h>
-#undef memcpy
+#undef memmove
 
 #if defined(RT_OS_DARWIN) || defined(RT_OS_WINDOWS)
 # ifndef __MINGW32__
-#  pragma weak memcpy
+#  pragma weak memmove
 # endif
 
 /* No alias support here (yet in the ming case). */
-extern void *(memcpy)(void *pvDst, const void *pvSrc, size_t cb)
+extern void *(memmove)(void *pvDst, const void *pvSrc, size_t cb)
 {
-    return RT_NOCRT(memcpy)(pvDst, pvSrc, cb);
+    return RT_NOCRT(memmove)(pvDst, pvSrc, cb);
 }
 
 #elif __GNUC__ >= 4
 /* create a weak alias. */
-__asm__(".weak memcpy\t\n"
-        " .set memcpy," RT_NOCRT_STR(memcpy) "\t\n");
+__asm__(".weak memmove\t\n"
+        " .set memmove," RT_NOCRT_STR(memmove) "\t\n");
 #else
 /* create a weak alias. */
-extern __typeof(RT_NOCRT(memcpy)) memcpy __attribute__((weak, alias(RT_NOCRT_STR(memcpy))));
+extern __typeof(RT_NOCRT(memmove)) memmove __attribute__((weak, alias(RT_NOCRT_STR(memmove))));
 #endif