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e1f414b6 1/** @file\r
2 64-bit left rotation for Ia32\r
3\r
4 Copyright (c) 2006 - 2007, Intel Corporation<BR>\r
5 All rights reserved. This program and the accompanying materials\r
6 are licensed and made available under the terms and conditions of the BSD License\r
7 which accompanies this distribution. The full text of the license may be found at\r
8 http://opensource.org/licenses/bsd-license.php\r
9\r
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
12\r
13**/\r
14\r
1efcc4ae 15\r
f734a10a 16\r
e1f414b6 17\r
42eedea9 18/**\r
19 Rotates a 64-bit integer left between 0 and 63 bits, filling\r
20 the low bits with the high bits that were rotated.\r
21\r
22 This function rotates the 64-bit value Operand to the left by Count bits. The\r
23 low Count bits are fill with the high Count bits of Operand. The rotated\r
24 value is returned.\r
25\r
26 @param Operand The 64-bit operand to rotate left.\r
27 @param Count The number of bits to rotate left.\r
28\r
29 @return Operand <<< Count\r
30\r
31**/\r
e1f414b6 32UINT64\r
33EFIAPI\r
34InternalMathLRotU64 (\r
35 IN UINT64 Operand,\r
36 IN UINTN Count\r
37 )\r
38{\r
39 _asm {\r
40 mov cl, byte ptr [Count]\r
41 mov edx, dword ptr [Operand + 4]\r
42 mov eax, dword ptr [Operand + 0]\r
43 shld ebx, edx, cl\r
44 shld edx, eax, cl\r
45 ror ebx, cl\r
46 shld eax, ebx, cl\r
47 test cl, 32 ; Count >= 32?\r
48 cmovnz ecx, eax\r
49 cmovnz eax, edx\r
50 cmovnz edx, ecx\r
51 }\r
52}\r
53\r