To compile to the same bit pattern binary, you'd need the same optimization settings (easy) with the same compiler (harder).

Intel can just give the source, but you can't trust Intel to just give you the same compiler they used, because the compiler might insert a backdoor. You'd need the compiler source, audit it for backdoors, then compile that with a trustworthy compiler. Then use the resulting compiler to compile the ME source.

(Compiler compiler compiler)