cfgexpand: Expand comment on when non-var clobbers can show up

The comment here is not wrong, just it would be better if mentioning
the C++ front-end instead of just the nested function lowering.

gcc/ChangeLog:

	* cfgexpand.cc (add_scope_conflicts_1): Expand comment
	on when non-var clobbers show up.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>

diff --git a/gcc/cfgexpand.cc b/gcc/cfgexpand.cc
index f32cf1b20c9a9590609a5bdb124ba15b2ac9c41b..6c1096363afb60991de8dac06df54bb4d3fce134 100644 (file)
--- a/gcc/cfgexpand.cc
+++ b/gcc/cfgexpand.cc
@@ -639,8 +639,9 @@ add_scope_conflicts_1 (basic_block bb, bitmap work, bool for_conflict)
        {
          tree lhs = gimple_assign_lhs (stmt);
          unsigned *v;
-         /* Nested function lowering might introduce LHSs
-            that are COMPONENT_REFs.  */
+         /* Handle only plain var clobbers.
+            Nested functions lowering and C++ front-end inserts clobbers
+            which are not just plain variables.  */
          if (!VAR_P (lhs))
            continue;
          if (DECL_RTL_IF_SET (lhs) == pc_rtx