Re: Can I Decompile asm to cpp source code

From: Claudio Puviani (puviani_at_hotmail.com)
Date: 03/15/04 

Date: Mon, 15 Mar 2004 19:28:26 GMT

"David Harmon" <source@netcom.com> wrote
> On Mon, 15 Mar 2004 10:44:47 +0100 in comp.lang.c++, "Guest"
> <nospam@nospam.com> wrote,
> >Is ther any decompiler to make cpp source code from asm code.
>
> No.
>
> Writing a good decompiler is at least as much work as writing a good
> optimizing compiler, a huge amount of work. Some would say it's
> impossible, but like most impossible things they are going to some
> day be proven wrong.

Since there's an n:m relationship between source code and object code, the best
one could achieve with a decompiler is a semantically equivalent output, and
most of the meaning is then lost. Even with disassemblers, where the
relationship is _almost_ 1:1 (some assemblers optimize certain instructions or
blocks of instructions), the output is severely incomplete relative to the
original source, and that's even without factoring in the comments.

> For now, the market for decompilers is very small compared to
> compilers and other types of software, and except for some
> academic work nobody has found it worth the trouble.
>
> For a point of view disagreeing with me, see [37.4] in Marshall Cline's
> C++ FAQ. It is always good to check the FAQ before posting. You can
> get the FAQ at: http://www.parashift.com/c++-faq-lite/
>
> He's mostly wrong, but the answer for now is still "No."

He's mostly right, actually.

Claudio Puviani

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