diff options
Diffstat (limited to 'gcc/tree-ssanames.c')
| -rw-r--r-- | gcc/tree-ssanames.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c index 5404edd..9cbe352 100644 --- a/gcc/tree-ssanames.c +++ b/gcc/tree-ssanames.c @@ -26,6 +26,7 @@ Boston, MA 02110-1301, USA. */ #include "varray.h" #include "ggc.h" #include "tree-flow.h" +#include "tree-pass.h" /* Rewriting a function into SSA form can create a huge number of SSA_NAMEs, many of which may be thrown away shortly after their creation if jumps @@ -304,3 +305,48 @@ replace_ssa_name_symbol (tree ssa_name, tree sym) SSA_NAME_VAR (ssa_name) = sym; 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. */ +static unsigned int +release_dead_ssa_names (void) +{ + tree t, next; + int n = 0; + referenced_var_iterator rvi; + + /* Current defs point to various dead SSA names that in turn points to dead + statements so bunch of dead memory is holded from releasing. */ + FOR_EACH_REFERENCED_VAR (t, rvi) + set_current_def (t, NULL); + /* Now release the freelist. */ + for (t = FREE_SSANAMES (cfun); t; t = next) + { + next = TREE_CHAIN (t); + ggc_free (t); + n++; + } + FREE_SSANAMES (cfun) = NULL; + if (dump_file) + fprintf (dump_file, "Released %i names, %.2f%%\n", n, n * 100.0 / num_ssa_names); + return 0; +} + +struct tree_opt_pass pass_release_ssa_names = +{ + "release_ssa", /* name */ + NULL, /* gate */ + release_dead_ssa_names, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + PROP_ssa, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + 0, /* todo_flags_finish */ + 0 /* letter */ +}; |