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- /** @file
- 64-bit Math Worker Function.
- The 32-bit versions of C compiler generate calls to library routines
- to handle 64-bit math. These functions use non-standard calling conventions.
- Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>
- SPDX-License-Identifier: BSD-2-Clause-Patent
- **/
- /*
- * Shifts a 64-bit unsigned value right by a certain number of bits.
- */
- __declspec(naked) void __cdecl _aullshr (void)
- {
- _asm {
- ;
- ; Checking: Only handle 64bit shifting or more
- ;
- cmp cl, 64
- jae _Exit
- ;
- ; Handle shifting between 0 and 31 bits
- ;
- cmp cl, 32
- jae More32
- shrd eax, edx, cl
- shr edx, cl
- ret
- ;
- ; Handle shifting of 32-63 bits
- ;
- More32:
- mov eax, edx
- xor edx, edx
- and cl, 31
- shr eax, cl
- ret
- ;
- ; Invalid number (less then 32bits), return 0
- ;
- _Exit:
- xor eax, eax
- xor edx, edx
- ret
- }
- }
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