This patch gets the compiler on the receiving end mostly started up
properly.  A lot of work has been done to get ssa form properly
started.  The current code may be overkill, but that is not important now. 

The current code exposes one known bug, that dannyb is looking into:
================
extern int foo (int);

int foo (int a)
{
  return a * 6;
}
=================

This program seems to serialize fine, but blows up in the expander
trying to expand the parm_decl.  It is possible that this is caused by
me failing to serialize something, or i could be just not initializing
something properly.

I have run a couple of other small examples thru.
================
extern int foo (void);

int foo (void)
{
  int a,b = 2;
  for (a = 0; a < 10; a++)
    b = 6 * a;
  return b * 6;
}
=================
now works fine.  I am starting to work on larger programs.

Mark claims that everything on his end should work except for static
initializers so we may be ready for some larger scale testing as soon as
the above bug is tracked down.

Committed as revision 127125.

Kenny

2007-07-31  Kenneth Zadeck <zadeck@naturalbridge.com>

    * tree-into-ssa.c (rebuild_ssa_for_lto): New function.
    (pass_rebuild_ssa_for_lto): New pass.
    * cgraph_build.c (tree_opt_pass pass_rebuild_cgraph): Added some
dumping.
    * lto-tree-flags.def (tcc_declaration): Added used_flag to
serialized list.
    (SSA_NAME): Added nothrow_flag and volatile_flag to serialized list.
    * tree-pass.h (pass_early_lto_passes, pass_rebuild_ssa_for_lto): New
passes.
    * lto-function-out.c (output_tree_flags): Added code to properly
    control writing of flags. Also added new parameter to pass in the
    tree code.
    (output_record_start, output_local_vars): Added param to
    output_tree_flags.
    (output_tree_list, output_eh_cleanup, output_eh_try,
    output_eh_catch, output_eh_allowed, output_eh_must_not_throw,
    output_eh_regions): Added missing debugging undent.
    (output_expr_operand): Added assert that there was no rtl and code
    to properly handle COND_EXPR.  Fixed the outputing of types and
    flags for many tree codes.
    (output_phi): Fixed the outputing of types and flags.  Generalized
    to handle parameters to phi that are not SSA_NAMES.
    (output_bb, LTO_SET_DEBUGGING_STREAM): Added assert to check for
    proper debug stream usage.
    (lto_static_init): Changed the outputting of flags and types for
    various tree codes.
    (pass_ipa_lto_out): Added dumping.
    * ipa-inline.c (pass_inline_parameters): Added dumping.
    * lto-tree-tags.def (COND_EXPR): Changed processing options.
    * lto-tags.h: Changed define into enum.
    * ipa.c (gate_ipa_fun_and_var_visibility): Always execute this
    pass.
    * tree.def (COND_EXEC): Properly documented this code.
    * tree-dfa.c (find_referenced_vars): Added code to walk phi
    functions.
    (pass_referenced_vars): Added name and dump flag.
    (find_vars_r): Now handles SSA_NAMES.
    * tree-optimize.c (gate_early_lto_passes): New function.
    (pass_early_lto_passes): New pass.
    * passes.c (pass_early_lto_passes): New pass.
    (dump_properties, debug_properties): New debugging function.
    * tree-ssanames.c (pass_release_ssa_names): Added dumping.


2007-07-31  Kenneth Zadeck <zadeck@naturalbridge.com>

    * lto-read.c (input_expr_operand): Fixed code for COND_EXEC,
    RETURN_EXPR, MODIFY_EXPR and processing of flags.
    (input_phi): Made work with operands other than SSA_NAMES and
    fixed processing of flags.
    (input_ssa_names): Initialize SSA_NAME_DEF_STMT to empty stmt.
    (input_flags): New function.
    * lto-lang.c (lto_init): Changed state of in_lto_p.