Use of Shl in assembly

Posted by user3097712 on Stack Overflow See other posts from Stack Overflow or by user3097712
Published on 2014-06-03T02:28:24Z Indexed on 2014/06/03 3:26 UTC
Read the original article Hit count: 113

Filed under:

assembly

I have the following piece of lines and I do not understand that. Hope that someone can help me:

.....
MOV EAX, DWORD PTR SS:[EBP-0x4]
SHL EAX, 0x2
ADD EAX, DWORD PTR SS:[EBP-0x8]
PUSH EAX
....

Normally, it helps me to translate that into C language. But somehow I cant find a way to do it in that case. So, I only know that in the second line with SHL the register is multiplied by 4. And that the DWORD PTR SS:[EBP-0x4] looks like an array representation but i am not sure.

I also find the following link

x86 Assembler: shl and other instructions

But I dont understand the answer there. So my question would be: What it is going on there? Thx...

Related posts about assembly

More information wanted on error: CREATE ASSEMBLY for assembly failed because assembly failed verif

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a small application that uses SQL Server 2005 Express with CLR stored procedures. It has been successfully installed and runs on many computers running XP and Vista. To create the assembly the following SQL is executed (names changed to protect the innocent): CREATE ASSEMBLY myAssemblyName… >>> More
Installed SQL Server 2008 and now TFS is broken.

as seen on Server Fault - Search for 'Server Fault'
Hi, My W2K3 server was running TFS 2008 SP1, SQL Server 2005 Development edition. I installed SQL Server 2008 Standard. I installed it while leaving SQL Server 2005 alone. Upgrading was not possible due to the differences in editions of the SQL Servers. Now TFS is broken. On a client computer… >>> More
How to Specify AssemblyKeyFile Attribute in .NET Assembly and Issues

as seen on Microsoft .NET Support Team - Search for 'Microsoft .NET Support Team'
How to specify strong key file in assembly? Answer: You can specify snk file information using following line [assembly: AssemblyKeyFile(@"c:\Key2.snk")] Where to specify an strong key file (snk file)? Answer: You have two options to specify the AssemblyKeyFile infromation. 1. In… >>> More
Assembly Language Question: Display Characters to screen LIFO (Last In First Out) in assembly langua

as seen on Stack Overflow - Search for 'Stack Overflow'
Given a stack that displays characters to the screen First in First Out(FIFO), how do you switch it to display them Last in First Out(LIFO). Theoretically speaking... is it simply just sending the characters to print in reverse order? >>> More
c# - can you make a "weak" assembly reference to a strong named assembly

as seen on Stack Overflow - Search for 'Stack Overflow'
hi, for various reasons i would rather not use strong named (signed) assemblies in my project. however, one of the projects is referenced by a sharepoint web part which means it must be signed. is it possible to have this assembly signed but when I reference it from other projects, to do so using… >>> More

Developer IT