revised PATCH: CALL_EXPR representation changes, part 0/9 (table of contents)

[Sandra Loosemore]

Here is the modified set of CALL_EXPR patches, incorporating fixes for review 
comments from Ian, Diego, and others.  Organization of the patches is the same 
as for the first round:

1: The actual tree.{h,c,def} changes and associated documentation change.
2. A very large chunk of changes to builtins.c and fold-const.c.
3. All the random middle end and other changes in the main gcc directory.
4. All the back end changes in gcc/config.
5. C front end changes.
6. C++ front end changes.
7. Java front end changes.
8. OBJC front end changes.
9. Fortran front end changes.

See my message introducing the first iteration of these patches at 
http://gcc.gnu.org/ml/gcc-patches/2007-02/msg00911.html for more background 
information.

Specific changes made since the first version posted on 2/10 include:

* The CALL_EXPR accessors, constructors, and iterators now work only on real 
CALL_EXPRs.  We've added a parallel interface for AGGR_INIT_EXPR in the C++ 
front end.

* CALL_EXPR_ARG0, CALL_EXPR_ARG1, and CALL_EXPR_ARG2 are gone, with uses 
replaced by the more general CALL_EXPR_ARG.

* I've fixed some bugs that crept into the merge of builtins.c that we didn't 
catch before posting the last version.

* Other small issues as identified by reviewers and/or myself.

Since posting the last version, I've also tested on SPARC and made sure we built 
and tested the obj-c++ front end.

OK to commit now?

-Sandra