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-rw-r--r--OldMdePkg/Library/BaseLib/Ia32/LShiftU64.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/OldMdePkg/Library/BaseLib/Ia32/LShiftU64.c b/OldMdePkg/Library/BaseLib/Ia32/LShiftU64.c
new file mode 100644
index 0000000000..193a41222f
--- /dev/null
+++ b/OldMdePkg/Library/BaseLib/Ia32/LShiftU64.c
@@ -0,0 +1,33 @@
+/** @file
+ 64-bit left shift function for IA-32.
+
+ Copyright (c) 2006 - 2007, Intel Corporation<BR>
+ 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.
+
+**/
+
+UINT64
+EFIAPI
+InternalMathLShiftU64 (
+ IN UINT64 Operand,
+ IN UINTN Count
+ )
+{
+ _asm {
+ mov cl, byte ptr [Count]
+ xor eax, eax
+ mov edx, dword ptr [Operand + 0]
+ test cl, 32 // Count >= 32?
+ cmovz eax, edx
+ cmovz edx, dword ptr [Operand + 4]
+ shld edx, eax, cl
+ shl eax, cl
+ }
+}
+