[PATCH] Make sure cfg-cleanup runs
Richard Biener
rguenther@suse.de
Wed Jun 18 07:56:00 GMT 2014
This makes sure we run cfg-cleanup when we propagate into PHI nodes
or on the FRE/PRE side remove any stmt. Otherwise we can end up
with not removed forwarder blocks.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.
Richard.
2014-06-18 Richard Biener <rguenther@suse.de>
* tree-ssa-propagate.c (replace_phi_args_in): Return whether
we propagated anything.
(substitute_and_fold_dom_walker::before_dom_children): Something
changed if we propagated into PHI arguments.
* tree-ssa-pre.c (eliminate): Always schedule cfg-cleanup if
we removed a stmt.
Index: gcc/tree-ssa-propagate.c
===================================================================
--- gcc/tree-ssa-propagate.c (revision 211738)
+++ gcc/tree-ssa-propagate.c (working copy)
@@ -964,7 +964,7 @@ replace_uses_in (gimple stmt, ssa_prop_g
/* Replace propagated values into all the arguments for PHI using the
values from PROP_VALUE. */
-static void
+static bool
replace_phi_args_in (gimple phi, ssa_prop_get_value_fn get_value)
{
size_t i;
@@ -1015,6 +1015,8 @@ replace_phi_args_in (gimple phi, ssa_pro
fprintf (dump_file, "\n");
}
}
+
+ return replaced;
}
@@ -1066,7 +1068,7 @@ substitute_and_fold_dom_walker::before_d
continue;
}
}
- replace_phi_args_in (phi, get_value_fn);
+ something_changed |= replace_phi_args_in (phi, get_value_fn);
}
/* Propagate known values into stmts. In some case it exposes
Index: gcc/tree-ssa-pre.c
===================================================================
--- gcc/tree-ssa-pre.c (revision 211738)
+++ gcc/tree-ssa-pre.c (working copy)
@@ -4521,11 +4521,7 @@ eliminate (bool do_pre)
gsi = gsi_for_stmt (stmt);
if (gimple_code (stmt) == GIMPLE_PHI)
- {
- remove_phi_node (&gsi, true);
- /* Removing a PHI node in a block may expose a forwarder block. */
- el_todo |= TODO_cleanup_cfg;
- }
+ remove_phi_node (&gsi, true);
else
{
basic_block bb = gimple_bb (stmt);
@@ -4534,6 +4530,9 @@ eliminate (bool do_pre)
bitmap_set_bit (need_eh_cleanup, bb->index);
release_defs (stmt);
}
+
+ /* Removing a stmt may expose a forwarder block. */
+ el_todo |= TODO_cleanup_cfg;
}
el_to_remove.release ();
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