diff options
Diffstat (limited to 'gcc/cfgcleanup.c')
| -rw-r--r-- | gcc/cfgcleanup.c | 42 |
1 files changed, 33 insertions, 9 deletions
diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c index 017a4aa5390..a4dccbea805 100644 --- a/gcc/cfgcleanup.c +++ b/gcc/cfgcleanup.c @@ -1510,7 +1510,6 @@ try_optimize_cfg (mode) bool changed_overall = false; bool changed; int iterations = 0; - sbitmap blocks; if (mode & CLEANUP_CROSSJUMP) add_noreturn_fake_exit_edges (); @@ -1673,11 +1672,6 @@ try_optimize_cfg (mode) if (mode & CLEANUP_CROSSJUMP) remove_fake_edges (); - if ((mode & CLEANUP_UPDATE_LIFE) && changed_overall) - update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL, - PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE - | PROP_KILL_DEAD_CODE | PROP_LOG_LINKS); - for (i = 0; i < n_basic_blocks; i++) BASIC_BLOCK (i)->aux = NULL; @@ -1720,9 +1714,39 @@ cleanup_cfg (mode) bool changed = false; timevar_push (TV_CLEANUP_CFG); - changed = delete_unreachable_blocks (); - if (try_optimize_cfg (mode)) - delete_unreachable_blocks (), changed = true; + if (delete_unreachable_blocks ()) + { + changed = true; + /* We've possibly created trivially dead code. Cleanup it right + now to introduce more oppurtunities for try_optimize_cfg. */ + if (!(mode & (CLEANUP_UPDATE_LIFE | CLEANUP_PRE_SIBCALL)) + && !reload_completed) + delete_trivially_dead_insns (get_insns(), max_reg_num ()); + } + while (try_optimize_cfg (mode)) + { + delete_unreachable_blocks (), changed = true; + if (mode & CLEANUP_UPDATE_LIFE) + { + /* Cleaning up CFG introduces more oppurtunities for dead code + removal that in turn may introduce more oppurtunities for + cleaning up the CFG. */ + if (!update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL, + PROP_DEATH_NOTES + | PROP_SCAN_DEAD_CODE + | PROP_KILL_DEAD_CODE + | PROP_LOG_LINKS)) + break; + } + else if (!(mode & CLEANUP_PRE_SIBCALL) && !reload_completed) + { + if (!delete_trivially_dead_insns (get_insns(), max_reg_num ())) + break; + } + else + break; + delete_dead_jumptables (); + } /* Kill the data we won't maintain. */ free_EXPR_LIST_list (&label_value_list); |