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e1f414b6 1/** @file\r
2 64-bit right 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 right between 0 and 63 bits, filling\r
20 the high bits with the high low bits that were rotated.\r
21\r
22 This function rotates the 64-bit value Operand to the right by Count bits.\r
23 The high Count bits are fill with the low Count bits of Operand. The rotated\r
24 value is returned.\r
25\r
26 @param Operand The 64-bit operand to rotate right.\r
27 @param Count The number of bits to rotate right.\r
28\r
29 @return Operand >>> Count\r
30\r
31**/\r
e1f414b6 32UINT64\r
33EFIAPI\r
34InternalMathRRotU64 (\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 eax, dword ptr [Operand + 0]\r
42 mov edx, dword ptr [Operand + 4]\r
43 shrd ebx, eax, cl\r
44 shrd eax, edx, cl\r
45 rol ebx, cl\r
46 shrd edx, 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