TREE_TYPE (ssa_name) = TREE_TYPE (sym);
}
-/* Return SSA names that are unused to GGC memory. This is used to keep
- footprint of compiler during interprocedural optimization.
- As a side effect the SSA_NAME_VERSION number reuse is reduced
- so this function should not be used too often. */
+/* Return SSA names that are unused to GGC memory and compact the SSA
+ version namespace. This is used to keep footprint of compiler during
+ interprocedural optimization. */
static unsigned int
release_dead_ssa_names (void)
{
tree t;
+ unsigned i, j;
int n = VEC_length (tree, FREE_SSANAMES (cfun));
referenced_var_iterator rvi;
eventually dead variables so a bunch of memory is held live. */
FOR_EACH_REFERENCED_VAR (cfun, t, rvi)
set_current_def (t, NULL);
+
/* Now release the freelist. */
VEC_free (tree, gc, FREE_SSANAMES (cfun));
FREE_SSANAMES (cfun) = NULL;
+ /* And compact the SSA number space. We make sure to not change the
+ relative order of SSA versions. */
+ for (i = 1, j = 1; i < VEC_length (tree, cfun->gimple_df->ssa_names); ++i)
+ {
+ tree name = ssa_name (i);
+ if (name)
+ {
+ if (i != j)
+ {
+ SSA_NAME_VERSION (name) = j;
+ VEC_replace (tree, cfun->gimple_df->ssa_names, j, name);
+ }
+ j++;
+ }
+ }
+ VEC_truncate (tree, cfun->gimple_df->ssa_names, j);
+
statistics_counter_event (cfun, "SSA names released", n);
+ statistics_counter_event (cfun, "SSA name holes removed", i - j);
if (dump_file)
- fprintf (dump_file, "Released %i names, %.2f%%\n",
- n, n * 100.0 / num_ssa_names);
+ fprintf (dump_file, "Released %i names, %.2f%%, removed %i holes\n",
+ n, n * 100.0 / num_ssa_names, i - j);
return 0;
}