3 #Copyright (c) 2006, Intel Corporation
4 #All rights reserved. This program and the accompanying materials
5 #are licensed and made available under the terms and conditions of the BSD License
6 #which accompanies this distribution. The full text of the license may be found at
7 #http://opensource.org/licenses/bsd-license.php
9 #THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 #WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18 # 64-bit left shift function for IA-32
23 #---------------------------------------------------------------------------
28 #---------------------------------------------------------------------------
29 .globl ASM_PFX(LShiftU64)
40 # This routine allows a 64 bit value to be left shifted by 32 bits and
41 # returns the shifted value.
42 # Count is valid up 63. (Only Bits 0-5 is valid for Count)
46 # Operand - Value to be shifted
47 # Count - Number of times to shift left.
51 # Value shifted left identified by the Count.
56 movl 4(%esp), %eax # dword ptr Operand[0]
57 movl 8(%esp), %edx # dword ptr Operand[4]
60 # CL is valid from 0 - 31. shld will move EDX:EAX by CL times but EAX is not touched
61 # For CL of 32 - 63, it will be shifted 0 - 31 so we will move eax to edx later.
63 movl 0xC(%esp), %ecx # Count
69 # Since Count is 32 - 63, eax will have been shifted by 0 - 31
70 # If shifted by 32 or more, set lower 32 bits to zero.