How do I view the compiled machine code or byte code for a C++ function in Visual Studio 2010?

Question

What is the best (quickest) way to view the code that the compiler generated from my files? I'm using mostly C++ but a solution that works for .NET languages would be very welcome as well.

Answer 1

Within Visual Studio, go to the property pages for your project, then go to C/C++ → Output Files → Assembler Output. It should look something like this:

Note the corresponding compiler switches, all variants of /FA.

• /FA: Assembly-Only Listing
• /FAcs: Assembly, Machine Code and Source
• /FAc: Assembly With Machine Code
• /FAs: Assembly With Source Code

Underneath the "Assembler Output" option there's an "ASM List Location" option. This is equivalent to the /Fa switch (note capitalization!), and it sets the file path of the output listing.

You can also look at the assembly while debugging (at a breakpoint), complete with the corresponding source code, by right-clicking the current line in the source file text area and clicking "Go To Disassembly".

It'll jump to the assembly at the line you right-clicked on in a separate tab. The listing will resemble this:

_{Yes I know, the screenshots are not from Visual Studio 2010 but the steps and the general appearance are the same. I just don't have immediate access to VS2010 to make screenshots with. :-)}

Answer 2

For a C++ project, compile with /FA to get an assembly listing.

For .NET assemblies, there's ildasm.