On Wed, Nov 25, 2015 at 03:16:53PM +0000, Joseph Myers wrote:
> > Wonder if we couldn't use some FE specific bit on the SAVE_EXPR to say
> > whether c_fully_fold_internal has already processed it or not, and just
> > get rid of c_save_expr, in c_fully_fold* recurse into SAVE_EXPRs too, but
> > only if that bit is not yet already set, and set it afterwards.
>
> I suppose you could do that, in line with the general principle of
> reducing early folding (as long as you ensure that folding the contents of
> a SAVE_EXPR results in modifying that SAVE_EXPR so that all pointers to it
> stay pointing to the same tree node).
I had a go at this, but I'm now skeptical about removing c_save_expr.
save_expr calls fold (), so we need to ensure that we don't pass any
C_MAYBE_CONST_EXPRs into it, meaning that we'd need to call c_fully_fold before
save_expr anyway...
So maybe go the "remove C_MAYBE_CONST_EXPRs in SAVE_EXPRs in c_gimplify_expr"
way?
Marek
