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Diffstat (limited to 'Core/MdePkg/Library/BaseLib/Ia32/LRotU64.c')
-rw-r--r--Core/MdePkg/Library/BaseLib/Ia32/LRotU64.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/Core/MdePkg/Library/BaseLib/Ia32/LRotU64.c b/Core/MdePkg/Library/BaseLib/Ia32/LRotU64.c
new file mode 100644
index 0000000000..2e01ed8bb0
--- /dev/null
+++ b/Core/MdePkg/Library/BaseLib/Ia32/LRotU64.c
@@ -0,0 +1,55 @@
+/** @file
+ 64-bit left rotation for Ia32
+
+ 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.
+
+**/
+
+
+
+
+/**
+ Rotates a 64-bit integer left between 0 and 63 bits, filling
+ the low bits with the high bits that were rotated.
+
+ This function rotates the 64-bit value Operand to the left by Count bits. The
+ low Count bits are fill with the high Count bits of Operand. The rotated
+ value is returned.
+
+ @param Operand The 64-bit operand to rotate left.
+ @param Count The number of bits to rotate left.
+
+ @return Operand <<< Count
+
+**/
+UINT64
+EFIAPI
+InternalMathLRotU64 (
+ IN UINT64 Operand,
+ IN UINTN Count
+ )
+{
+ _asm {
+ mov cl, byte ptr [Count]
+ mov edx, dword ptr [Operand + 4]
+ mov eax, dword ptr [Operand + 0]
+ shld ebx, edx, cl
+ shld edx, eax, cl
+ ror ebx, cl
+ shld eax, ebx, cl
+ test cl, 32 ; Count >= 32?
+ jz L0
+ mov ecx, eax
+ mov eax, edx
+ mov edx, ecx
+L0:
+ }
+}
+