How to view the assembly behind the code using Visual C++?
There are several approaches:
You can normally see assembly code while debugging C++ in visual studio (and eclipse too). For this in Visual Studio put a breakpoint on code in question and when debugger hits it rigth click and find "Go To Assembly" ( or press CTRL+ALT+D )
Second approach is to generate assembly listings while compiling. For this go to project settings -> C/C++ -> Output Files -> ASM List Location and fill in file name. Also select "Assembly Output" to "Assembly With Source Code".
Compile the program and use any third-party debugger. You can use OllyDbg or WinDbg for this. Also you can use IDA (interactive disassembler). But this is hardcore way of doing it.
Specify the /FA switch for the cl compiler. Depending on the value of the switch either only assembly code or high-level code and assembly code is integrated. The filename gets .asm file extension. Here are the supported values:
- /FA Assembly code; .asm
- /FAc Machine and assembly code; .cod
- /FAs Source and assembly code; .asm
- /FAcs Machine, source, and assembly code; .cod
Additional note: there is big difference between Debug assembler output and Release one. The first one is good to learn how compiler produces assembler code from C++. The second one is good to learn how compiler optimizes various C++ constructs. In this case some C++-to-asm transformations are not obvious.
The easiest way is to fire the debugger and check the disassembly window.