1 files changed, 43 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/LShiftU64.S b/MdePkg/Library/BaseLib/Ia32/LShiftU64.S
new file mode 100644
index 000000000000..574583a0308e
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/LShiftU64.S
@@ -0,0 +1,43 @@
+#------------------------------------------------------------------------------
+#
+# Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
+# 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:
+#
+#   LShiftU64.S
+#
+# Abstract:
+#
+#   64-bit left shift function for IA-32
+#
+#------------------------------------------------------------------------------
+
+ASM_GLOBAL ASM_PFX(InternalMathLShiftU64)
+
+#------------------------------------------------------------------------------
+# UINT64
+# EFIAPI
+# InternalMathLShiftU64 (
+#   IN      UINT64                    Operand,
+#   IN      UINTN                     Count
+#   );
+#------------------------------------------------------------------------------
+ASM_PFX(InternalMathLShiftU64):
+    movb    12(%esp), %cl
+    xorl    %eax, %eax
+    movl    4(%esp), %edx
+    testb   $32, %cl                    # Count >= 32?
+    jnz     L0
+    movl    %edx, %eax
+    movl    0x8(%esp), %edx
+L0:    
+    shld    %cl, %eax, %edx
+    shl     %cl, %eax
+    ret