[cfe-commits] Patches for clang -ast-print

[Eli Friedman]

On Wed, Oct 31, 2012 at 9:27 AM, Jordan Rose <jordan_rose at apple.com> wrote:
>
> On Oct 29, 2012, at 17:39 , Eli Friedman <eli.friedman at gmail.com> wrote:
>
> On Mon, Oct 29, 2012 at 5:29 PM, Jordan Rose <jordan_rose at apple.com> wrote:
>
>
> On Oct 29, 2012, at 17:23 , Eli Friedman <eli.friedman at gmail.com> wrote:
>
> Since the CFG is a linearized structure now, it's not printing CFG
> structure. Instead, it's trying to show the statement associated with a
> single CFGElement, such as a cast, in a way that you could match it up with
> the source but still see the evaluation pattern.
>
>
> So we're printing what basically amounts to a derived analysis for all
> users?  I guess that makes sense, to some extent... but is there no
> way to formally query the CFGElements a given CFGElement depends on?
>
>
> In addition to Ted's response, I want to point out that the current dump may
> use placeholders for things the current element does not depend on for
> evaluation, e.g. a MemberExpr for a static member. Likewise, it may miss
> things that are dependencies: the semantic form of a PseudoObjectExpr. It's
> not a perfect format by any means...
>
>
> It is deliberately trying to print the syntactic ("pretty") form of the
> statement, but with placeholders for subexpressions that appear earlier in
> the CFG. Maybe these two goals are incompatible, but I can say that what we
> have has really helped us on the analyzer side.
>
>
> The issue comes down to the fact that you're trying to "pretty-print"
> things which aren't actually written in the source.  Maybe we need a
> PrintingPolicy bit for not-so-pretty-printing?
>
>
> ...and that does seem like we're venturing outside the intent of
> pretty-print, huh. I don't like the new form either, though, because it's
> even worse about implying that a given CFGElement is not consumed.
>
> If you're okay with adding a PrintImplicitNodes bit to PrintingPolicy that
> would be good enough for us. Otherwise we'll have to think of something
> else.

This seems okay to me.  Grzegorz?

-Eli