ArmPkg/CompilerIntrinsicsLib: Add memory intrinsics for RVCT

New intrinsics:  __aeabi_memmove, __aeabi_memset, __aeabi_memclr and __aeabi_memclr4



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12293 6f19259b-4bc3-4df7-8a09-765794883524

ArmPkg/Library/CompilerIntrinsicsLib/Arm/memmove.asm

@@ -0,0 +1,54 @@
+//------------------------------------------------------------------------------ 
+//
+// Copyright (c) 2011, ARM Limited. All rights reserved.
+//
+// This program and the accompanying materials
+// are licensed and made available under the terms and conditions of the BSD License
+// which accompanies this distribution.  The full text of the license may be found at
+// http://opensource.org/licenses/bsd-license.php
+//
+// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+//
+//------------------------------------------------------------------------------
+
+
+    EXPORT  __aeabi_memmove
+
+    AREA    Memmove, CODE, READONLY
+
+;
+;VOID
+;EFIAPI
+;__aeabi_memmove (
+; IN  VOID          *Destination,
+; IN  CONST VOID    *Source,
+; IN  UINT32        Size
+; );
+;
+__aeabi_memmove
+  CMP     r2, #0
+  BXEQ    r14
+  CMP     r0, r1
+  BXEQ    r14
+  BHI     memmove_backward
+  BLS     memmove_forward
+
+memmove_forward
+  LDRB    r3, [r1], #1
+  STRB    r3, [r0], #1
+  SUBS    r2, r2, #1
+  BXEQ    r14
+  B       memmove_forward
+
+memmove_backward
+  add     r0, r2
+  add     r1, r2
+memmove_backward_loop
+  LDRB    r3, [r1], #-1
+  STRB    r3, [r0], #-1
+  SUBS    r2, r2, #-1
+  BXEQ    r14
+  B       memmove_backward_loop
+
+  END