Re: Mapping of TREE_CODE to tree_node

[David Malcolm <dmalcolm@redhat.com>]

On Mon, 2023-06-26 at 18:59 +0200, Aaron Lorey via Gcc wrote:
> Hello,
> 
> this is the first time I am writing to a mailing list. I've tried
> researching the normal procedure but nothing special seems to be
> required.
> 
> I'm currently trying to do a complete graph-discovery of GCC's symtab
> /
> tree_nodes to dump the full internal representation of the
> compilation
> unit. Gitlab: https://gitlab.com/graph-prog/code-database
> 
> It is not exceptionally heavy but also not very easy to serialize the
> internal state to disk. I think this task was simply not considered
> in the
> design.
> 
> Reason for writing to the mailing list are the troubles in connecting
> the
> TREE_CODE enumeration to the appropriate struct tree_node memory
> layout
> without guessing.
> 
> Can you provide a mapping of TREE_CODE to tree_node memory layout?

I don't know that such a mapping exists directly, but have a look at
the functions "tree_code_size" and "tree_size" defined in gcc/tree.cc.

You might also find the LTO streaming code of interest; see gcc/lto-
streamer-{in,out}.cc

Hope this is helpful
Dave