1 files changed, 40 insertions, 0 deletions
diff --git a/MdePkg/Library/CompilerIntrinsicsLib/Arm/memmove.S b/MdePkg/Library/CompilerIntrinsicsLib/Arm/memmove.S
new file mode 100644
index 0000000000..d8588d3d98
--- /dev/null
+++ b/MdePkg/Library/CompilerIntrinsicsLib/Arm/memmove.S
@@ -0,0 +1,40 @@
+#------------------------------------------------------------------------------
+#
+# Copyright (c) 2011-2014, ARM Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#------------------------------------------------------------------------------
+
+#include <AsmMacroLib.h>
+
+# VOID
+# EFIAPI
+# memmove (
+#  IN  VOID          *Destination,
+#  IN  CONST VOID    *Source,
+#  IN  UINT32        Size
+#  );
+ASM_FUNC(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