ArmPkg/CompilerIntrinsicesLib: Fixed memmove() and memset()

[mirror_edk2.git] / ArmPkg / Library / CompilerIntrinsicsLib / Arm / memmove.asm

//------------------------------------------------------------------------------\r
//\r
// Copyright (c) 2011-2014, ARM Limited. All rights reserved.\r
//\r
// This program and the accompanying materials\r
// are licensed and made available under the terms and conditions of the BSD License\r
// which accompanies this distribution.  The full text of the license may be found at\r
// http://opensource.org/licenses/bsd-license.php\r
//\r
// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
//\r
//------------------------------------------------------------------------------\r
\r
\r
    EXPORT  __aeabi_memmove\r
\r
    AREA    Memmove, CODE, READONLY\r
\r
;\r
;VOID\r
;EFIAPI\r
;__aeabi_memmove (\r
; IN  VOID          *Destination,\r
; IN  CONST VOID    *Source,\r
; IN  UINT32        Size\r
; );\r
;\r
__aeabi_memmove\r
  CMP     r2, #0\r
  BXEQ    lr\r
  CMP     r0, r1\r
  BXEQ    lr\r
  BHI     memmove_backward\r
\r
memmove_forward\r
  LDRB    r3, [r1], #1\r
  STRB    r3, [r0], #1\r
  SUBS    r2, r2, #1\r
  BNE     memmove_forward\r
  BX      lr\r
\r
memmove_backward\r
  add     r0, r2\r
  add     r1, r2\r
memmove_backward_loop\r
  LDRB    r3, [r1, #-1]!\r
  STRB    r3, [r0, #-1]!\r
  SUBS    r2, r2, #1\r
  BNE     memmove_backward_loop\r
  BX      lr\r
\r
  END\r