[Bug tree-optimization/44563] GCC uses a lot of RAM when compiling a large numbers of functions

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=44563

--- Comment #16 from Richard Biener <rguenth at gcc dot gnu.org> ---
callgrind shows the cgraph_edge_hasher quite high in the profile (via
redirect_all_calls).  I suppose as the large main is a single BB walking
all stmts over-and-over is quite bad.  Also hash_pointer isn't inlined!?
Ah - it's external in libiberty hashtab.c ... - it should transition to
using/inheriting from pointer_hash.

cgraph_edge *
cgraph_node::get_edge (gimple call_stmt)
{
  cgraph_edge *e, *e2;
  int n = 0;

  if (call_site_hash)
    return call_site_hash->find_with_hash (call_stmt,
                                           htab_hash_pointer (call_stmt));


The estimate_calls_size_and_time portion is quite smaller.

cleanup-cfgs main portion is split_bb_on_noreturn_calls.