Kazu Hirata writes:
> Hi,
>
> I see that the implementation of LANG_HOOKS_GET_CALLEE_FNDECL in Java
> always returns NULL (at least for the time being).
>
> static tree
> java_get_callee_fndecl (tree call_expr)
> {
> tree method, table, element, atable_methods;
>
> HOST_WIDE_INT index;
>
> /* FIXME: This is disabled because we end up passing calls through
> the PLT, and we do NOT want to do that. */
> return NULL;
>
> :
> :
>
> Is anybody planning to fix this?
Yes.
The problem is that I want to expose opportunities for inlining but I
do not want calls to global functions to go through the PLT as
required by C semantics. To do that causes endless problems.
We now generate local aliases for all global functions, so my
intention is to call those aliases, rather than the global functions
themselves. But I do need to give inlining a chance to work, and for
that to happen the middle end needs to see the _real_ function decl.
> If not, I'm thinking about removing this language hook. The reason
> is not just clean up. Rather it is because I need to change the
> prototype of get_callee_fndecl and
> LANG_HOOKS_GET_CALLEE_FNDECL.. Currently, fold_ternary has the
> following call tree.
>
> fold_ternary
> get_callee_fndecl
> java_get_callee_fndecl
>
> If I change fold_ternary to take components of CALL_EXPR like the
> address expression of CALL_EXPR and the argument list, instead of
> CALL_EXPR itself, I would have to change java_get_callee_fndecl to
> take the first operand of a CALL_EXPR, instead of a CALL_EXPR.
So do that.
> It's not that the change is so involved, but it doesn't make much
> sense to keep something dead up to date.
It's not dead, it's resting.
> In other words, when I posted the following patch
>
> http://gcc.gnu.org/ml/gcc-patches/2005-03/msg02038.html
>
> Roger Sayle requested to keep the call to get_callee_fndecl so that we
> can "fold" the first operand of a CALL_EXPR to a FUNCTION_DECL.
That's a good thing to do.
> FYI, the above FIXME comes from
>
> http://gcc.gnu.org/ml/java-patches/2004-q2/msg00083.html
Andrew.
