ArmPkg/CompilerIntrinsicsLib: Make __aeabi_memcpy the same as memcpy

This code also removed some redundant instructions.

__aeabi_memcpy doesn't require preservation of r0 (as memcpy does),
which could save a push, but the code has been left to keep things consistent.

The reason __aeabi_memcpy has been added to the .S file is so it will be available
to toolchains that use the GCC assembler but the full ARM EABI (i.e. current LLVM)

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15124 6f19259b-4bc3-4df7-8a09-765794883524

ArmPkg/Library/CompilerIntrinsicsLib/Arm/memcpy.asm

@@ -1,4 +1,4 @@
-//------------------------------------------------------------------------------ 
+//------------------------------------------------------------------------------
 //
 // Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
 //
@@ -27,14 +27,15 @@
 ; );
 ;
 __aeabi_memcpy
-    CMP     r2, #0
-    BXEQ    r14
-loop
-    LDRB    r3, [r1], #1
-    STRB    r3, [r0], #1
-    SUBS    r2, r2, #1
-    BXEQ    r14
-    B       loop
-        
-    END
+  cmp     r2, #0
+  bxeq    lr
+  push    {lr}
+  mov     lr, r0
+L5
+  ldrb  r3, [r1], #1
+  strb  r3, [lr], #1
+  subs r2, r2, #1
+  bne  L5
+  pop  {pc}
 
+  END