2009-05-08 Paolo Bonzini <bonzini@gnu.org>
PR rtl-optimization/33928
PR 26854
* fwprop.c (use_def_ref, get_def_for_use, bitmap_only_bit_bitween,
process_uses, build_single_def_use_links): New.
(update_df): Update use_def_ref.
(forward_propagate_into): Use get_def_for_use instead of use-def
chains.
(fwprop_init): Call build_single_def_use_links and let it initialize
dataflow.
(fwprop_done): Free use_def_ref.
(fwprop_addr): Eliminate duplicate call to df_set_flags.
* df-problems.c (df_rd_simulate_artificial_defs_at_top,
df_rd_simulate_one_insn): New.
(df_rd_bb_local_compute_process_def): Update head comment.
(df_chain_create_bb): Use the new RD simulation functions.
* df.h (df_rd_simulate_artificial_defs_at_top,
df_rd_simulate_one_insn): New.
* opts.c (decode_options): Enable fwprop at -O1.
* doc/invoke.texi (-fforward-propagate): Document this.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@147282 138bc75d-0d04-0410-961f-82ee72b054a4