2014-08-20 Martin Jambor <mjambor@suse.cz>

	    Wei Mi  <wmi@google.com>

	PR ipa/60449
	PR middle-end/61776
	* tree-ssa-operands.c (update_stmt_operands): Remove
	MODIFIED_NORETURN_CALLS.
	* tree-cfgcleanup.c (cleanup_call_ctrl_altering_flag): New func.
	(cleanup_control_flow_bb): Use cleanup_call_ctrl_altering_flag.
	(split_bb_on_noreturn_calls): Renamed from split_bbs_on_noreturn_calls.
	(cleanup_tree_cfg_1): Use split_bb_on_noreturn_calls.
	* tree-ssanames.h: Remove MODIFIED_NORETURN_CALLS.
	* gimple.h (enum gf_mask): Add GF_CALL_CTRL_ALTERING.
	(gimple_call_set_ctrl_altering): New func.
	(gimple_call_ctrl_altering_p): Ditto.
	* tree-cfg.c (gimple_call_initialize_ctrl_altering): Ditto.
	(make_blocks): Use gimple_call_initialize_ctrl_altering.
	(is_ctrl_altering_stmt): Use gimple_call_ctrl_altering_p.
	(execute_fixup_cfg): Use gimple_call_ctrl_altering_p and
	remove MODIFIED_NORETURN_CALLS.

2014-08-20  Martin Jambor  <mjambor@suse.cz>
	    Wei Mi  <wmi@google.com>

	PR ipa/60449
	PR middle-end/61776
	* testsuite/gcc.dg/lto/pr60449_1.c: New test.
	* testsuite/gcc.dg/lto/pr60449_0.c: New test.
	* testsuite/gcc.dg/pr61776.c: New test.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@214233 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 38 insertions, 23 deletions

diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c
index 2b6927e0437..a66ec6e7537 100644
--- a/gcc/tree-cfgcleanup.c
+++ b/gcc/tree-cfgcleanup.c
@@ -162,6 +162,23 @@ cleanup_control_expr_graph (basic_block bb, gimple_stmt_iterator gsi)
   return retval;
 }
 
+/* Cleanup the GF_CALL_CTRL_ALTERING flag according to
+   to updated gimple_call_flags.  */
+
+static void
+cleanup_call_ctrl_altering_flag (gimple bb_end)
+{
+  if (!is_gimple_call (bb_end)
+      || !gimple_call_ctrl_altering_p (bb_end))
+    return;
+
+  int flags = gimple_call_flags (bb_end);
+  if (((flags & (ECF_CONST | ECF_PURE))
+       && !(flags & ECF_LOOPING_CONST_OR_PURE))
+      || (flags & ECF_LEAF))
+    gimple_call_set_ctrl_altering (bb_end, false);
+}
+
 /* Try to remove superfluous control structures in basic block BB.  Returns
    true if anything changes.  */
 
@@ -182,6 +199,9 @@ cleanup_control_flow_bb (basic_block bb)
 
   stmt = gsi_stmt (gsi);
 
+  /* Try to cleanup ctrl altering flag for call which ends bb.  */
+  cleanup_call_ctrl_altering_flag (stmt);
+
   if (gimple_code (stmt) == GIMPLE_COND
       || gimple_code (stmt) == GIMPLE_SWITCH)
     retval |= cleanup_control_expr_graph (bb, gsi);
@@ -594,30 +614,24 @@ fixup_noreturn_call (gimple stmt)
    known not to return, and remove the unreachable code.  */
 
 static bool
-split_bbs_on_noreturn_calls (void)
+split_bb_on_noreturn_calls (basic_block bb)
 {
   bool changed = false;
-  gimple stmt;
-  basic_block bb;
+  gimple_stmt_iterator gsi;
 
-  /* Detect cases where a mid-block call is now known not to return.  */
-  if (cfun->gimple_df)
-    while (vec_safe_length (MODIFIED_NORETURN_CALLS (cfun)))
-      {
-	stmt = MODIFIED_NORETURN_CALLS (cfun)->pop ();
-	bb = gimple_bb (stmt);
-	/* BB might be deleted at this point, so verify first
-	   BB is present in the cfg.  */
-	if (bb == NULL
-	    || bb->index < NUM_FIXED_BLOCKS
-	    || bb->index >= last_basic_block_for_fn (cfun)
-	    || BASIC_BLOCK_FOR_FN (cfun, bb->index) != bb
-	    || !gimple_call_noreturn_p (stmt))
-	  continue;
+  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+    {
+      gimple stmt = gsi_stmt (gsi);
 
+      if (!is_gimple_call (stmt))
+	continue;
+
+      if (gimple_call_noreturn_p (stmt))
 	changed |= fixup_noreturn_call (stmt);
-      }
+    }
 
+  if (changed)
+    bitmap_set_bit (cfgcleanup_altered_bbs, bb->index);
   return changed;
 }
 
@@ -655,8 +669,6 @@ cleanup_tree_cfg_1 (void)
   basic_block bb;
   unsigned i, n;
 
-  retval |= split_bbs_on_noreturn_calls ();
-
   /* Prepare the worklists of altered blocks.  */
   cfgcleanup_altered_bbs = BITMAP_ALLOC (NULL);
 
@@ -672,7 +684,10 @@ cleanup_tree_cfg_1 (void)
     {
       bb = BASIC_BLOCK_FOR_FN (cfun, i);
       if (bb)
-	retval |= cleanup_tree_cfg_bb (bb);
+	{
+	  retval |= cleanup_tree_cfg_bb (bb);
+	  retval |= split_bb_on_noreturn_calls (bb);
+	}
     }
 
   /* Now process the altered blocks, as long as any are available.  */
@@ -689,9 +704,9 @@ cleanup_tree_cfg_1 (void)
 
       retval |= cleanup_tree_cfg_bb (bb);
 
-      /* Rerun split_bbs_on_noreturn_calls, in case we have altered any noreturn
+      /* Rerun split_bb_on_noreturn_calls, in case we have altered any noreturn
 	 calls.  */
-      retval |= split_bbs_on_noreturn_calls ();
+      retval |= split_bb_on_noreturn_calls (bb);
     }
 
   end_recording_case_labels ();