MdePkg/BaseLib: Support IA32 processors without CMOVx

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / RRotU64.asm

;------------------------------------------------------------------------------\r
;\r
; Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
; This program and the accompanying materials\r
; are licensed and made available under the terms and conditions of the BSD License\r
; which accompanies this distribution.  The full text of the license may be found at\r
; http://opensource.org/licenses/bsd-license.php.\r
;\r
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
;\r
; Module Name:\r
;\r
;   RRotU64.asm\r
;\r
; Abstract:\r
;\r
;   64-bit right rotation for Ia32\r
;\r
;------------------------------------------------------------------------------\r
\r
    .686\r
    .model  flat,C\r
    .code\r
\r
;------------------------------------------------------------------------------\r
; UINT64\r
; EFIAPI\r
; InternalMathRRotU64 (\r
;   IN      UINT64                    Operand,\r
;   IN      UINTN                     Count\r
;   );\r
;------------------------------------------------------------------------------\r
InternalMathRRotU64 PROC    USES    ebx\r
    mov     cl, [esp + 16]\r
    mov     eax, [esp + 8]\r
    mov     edx, [esp + 12]\r
    shrd    ebx, eax, cl\r
    shrd    eax, edx, cl\r
    rol     ebx, cl\r
    shrd    edx, ebx, cl\r
    test    cl, 32                      ; Count >= 32?\r
    jz      @F\r
    mov     ecx, eax                    ; switch eax & edx if Count >= 32\r
    mov     eax, edx\r
    mov     edx, ecx\r
@@:    \r
    ret\r
InternalMathRRotU64 ENDP\r
\r
    END\r