Re: Need help: Is a VAR_DECL type builtin or not?

[Dominik Vogt <vogt@linux.vnet.ibm.com>]

On Fri, Feb 14, 2014 at 02:40:44PM +0100, Richard Biener wrote:
> On Fri, Feb 14, 2014 at 9:59 AM, Dominik Vogt <vogt@linux.vnet.ibm.com> wrote:
> > Given a specific VAR_DECL tree node, I need to find out whether
> > its type is built in or not.  Up to now I have
> >
> >   tree tn = TYPE_NAME (TREE_TYPE (var_decl));
> >   if (tn != NULL_TREE && TREE_CODE (tn) == TYPE_DECL && DECL_NAME (tn))
> >     {
> >       ...
> >     }
> >
> > This if-condition is true for both,
> >
> >   int x;
> >   const int x;
> >   ...
> >
> > and
> >
> >   typedef int i_t;
> >   i_t x;
> >   const i_t x;
> >   ...
> >
> > I need to weed out the class of VAR_DECLs that directly use built
> > in types.
> 
> Try DECL_IS_BUILTIN.  But I question how you define "builtin" here?

Well, actually I'm working on the variable output function in
godump.c.  At the moment, if the code comes across

  typedef char c_t
  chat c1;
  c_t c2;

it emits

  type _c_t byte
  var c1 byte
  var c2 byte

This is fine for c1, but for c2 it should really use the type:

  var c2 _c_t

So the rule I'm trying to implement is:

  Given a Tree node that is a VAR_DECL, if its type is an "alias"
  (defined with typedef/union/struct/class etc.), use the name of
  the alias, otherwise resolve the type recursively until only
  types built into the language are left.

It's really only about the underlying data types (int, float,
_Complex etc.), not about storage classes, pointers, attributes,
qualifiers etc.

Well, since godump.c already caches all declarations it has come
across, I could assume that these declarations are not built-in
and use that in the "rule" above.

Ciao

Dominik ^_^  ^_^

-- 

Dominik Vogt
IBM Germany