How do I check if a function got CTFE?

[AsmMan via Digitalmars-d-learn]

I'd like to check if a function got CTFE, ie, the compiler was 
able to replace my foo(s); by the computed value at compile-time.

I'm trying to convert the binary executable to assembly by using 
objconv tool but I'm finding it very diffucult to find anything 
in there, since some converters I've used which does ELF to ASM 
keep the function name, e.g, foo() function is a foo label 
somewhere in the file but this convert doesn't and use some 
numbers instead of. I don't know if it's related how is the 
windows object file format designed.