Olivier Martin 284fb5c811 ArmPkg/CompilerIntrinsicesLib: Fixed memmove() and memset()
- Fixed memmove when going backward: the copy started one byte
  after the end of the region to copy
- memset: - removed unused register
          - fixed arguments size and character arguments were
            actually reversed
- Added memmove() to ARM32 GCC

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@16328 6f19259b-4bc3-4df7-8a09-765794883524
2014-11-11 00:52:11 +00:00

49 lines
1.3 KiB
ArmAsm

#------------------------------------------------------------------------------
#
# Copyright (c) 2011-2014, 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
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# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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.text
.align 2
GCC_ASM_EXPORT (memmove)
# VOID
# EFIAPI
# memmove (
# IN VOID *Destination,
# IN CONST VOID *Source,
# IN UINT32 Size
# );
ASM_PFX(memmove):
CMP r2, #0
BXEQ lr
CMP r0, r1
BXEQ lr
BHI memmove_backward
memmove_forward:
LDRB r3, [r1], #1
STRB r3, [r0], #1
SUBS r2, r2, #1
BXEQ lr
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 lr
B memmove_backward_loop