1 files changed, 90 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibMmx/Ia32/CopyMem.S b/MdePkg/Library/BaseMemoryLibMmx/Ia32/CopyMem.S
new file mode 100644
index 0000000000..56788cb981
--- /dev/null
+++ b/MdePkg/Library/BaseMemoryLibMmx/Ia32/CopyMem.S
@@ -0,0 +1,90 @@
+#------------------------------------------------------------------------------
+#
+# Copyright (c) 2006, Intel Corporation
+# 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.
+#
+# Module Name:
+#
+#   CopyMem.asm
+#
+# Abstract:
+#
+#   CopyMem function
+#
+# Notes:
+#
+#------------------------------------------------------------------------------
+
+    .686: 
+    #.MODEL flat,C
+    .xmm: 
+    .code: 
+
+#------------------------------------------------------------------------------
+#  VOID *
+#  _mem_CopyMem (
+#    IN VOID   *Destination,
+#    IN VOID   *Source,
+#    IN UINTN  Count
+#    )
+#------------------------------------------------------------------------------
+.global _InternalMemCopyMem
+_InternalMemCopyMem:
+    push    %esi
+    push    %edi
+    movl    16(%esp), %esi              # esi <- Source
+    movl    12(%esp), %edi              # edi <- Destination
+    movl    20(%esp), %edx              # edx <- Count
+    leal    -1(%edi,%edx,), %eax        # eax <- End of Destination
+    cmpl    %edi, %esi
+    jae     L0
+    cmpl    %esi, %eax                  # Overlapped?
+    jae     @CopyBackward               # Copy backward if overlapped
+L0: 
+    xorl    %ecx, %ecx
+    subl    %esi, %ecx
+    andl    $7, %ecx                    # ecx + esi aligns on 8-byte boundary
+    jz      L1
+    cmpl    %edx, %ecx
+    cmova   %edx, %ecx
+    subl    %ecx, %edx                  # edx <- remaining bytes to copy
+    rep
+    movsb
+L1: 
+    movl    %edx, %ecx
+    andl    $7, %edx
+    shrl    $3, %ecx                    # ecx <- # of Qwords to copy
+    jz      @CopyBytes
+    pushl   %eax
+    pushl   %eax
+    movq    %mm0, (%esp)                # save mm0
+L2: 
+    movq    (%esi), %mm0
+    movntq  %mm0, (%edi)
+    addl    $8, %esi
+    addl    $8, %edi
+    loop    L2
+    mfence
+    movq    (%esp), %mm0                # restore mm0
+    popl    %ecx                        # stack cleanup
+    popl    %ecx                        # stack cleanup
+    jmp     @CopyBytes
+@CopyBackward: 
+    movl    %eax, %edi                  # edi <- Last byte in Destination
+    leal    -1(%esi,%edx,), %esi        # esi <- Last byte in Source
+    std
+@CopyBytes: 
+    movl    %edx, %ecx
+    rep
+    movsb
+    cld
+    movl    12(%esp), %eax
+    push    %esi
+    push    %edi
+    ret