CloverBootloader/MdePkg/Library/BaseLib/Ia32/LRotU64.nasm

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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
; LRotU64.nasm
;
; Abstract:
;
; 64-bit left rotation for Ia32
;
;------------------------------------------------------------------------------
SECTION .text
;------------------------------------------------------------------------------
; UINT64
; EFIAPI
; InternalMathLRotU64 (
; IN UINT64 Operand,
; IN UINTN Count
; );
;------------------------------------------------------------------------------
global ASM_PFX(InternalMathLRotU64)
ASM_PFX(InternalMathLRotU64):
push ebx
mov cl, [esp + 16]
mov edx, [esp + 12]
mov eax, [esp + 8]
shld ebx, edx, cl
shld edx, eax, cl
ror ebx, cl
shld eax, ebx, cl
test cl, 32 ; Count >= 32?
jz .0
mov ecx, eax
mov eax, edx
mov edx, ecx
.0:
pop ebx
ret