[PATCH] Call free_dominance_info when transformed in DCE (PR rtl-optimization/89242).

[Martin Liška]

Hi.

The patch is very similar to r236460 where we should release dominance info
when the CFG is modified.

Patch can bootstrap on x86_64-linux-gnu and survives regression tests.

Ready to be installed?
Thanks,
Martin

gcc/ChangeLog:

2019-02-12  Martin Liska  <mli...@suse.cz>

        PR rtl-optimization/89242
        * dce.c (delete_unmarked_insns): Call free_dominance_info we
        process a transformation.

gcc/testsuite/ChangeLog:

2019-02-12  Martin Liska  <mli...@suse.cz>

        PR rtl-optimization/89242
        * g++.dg/pr89242.C: New test.
---
 gcc/dce.c                      |  1 +
 gcc/testsuite/g++.dg/pr89242.C | 15 +++++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/pr89242.C



diff --git a/gcc/dce.c b/gcc/dce.c
index cb18e81592a..8fb109c7388 100644
--- a/gcc/dce.c
+++ b/gcc/dce.c
@@ -652,6 +652,7 @@ delete_unmarked_insns (void)
     {
       gcc_assert (can_alter_cfg);
       delete_unreachable_blocks ();
+      free_dominance_info (CDI_DOMINATORS);
     }
 }
 
diff --git a/gcc/testsuite/g++.dg/pr89242.C b/gcc/testsuite/g++.dg/pr89242.C
new file mode 100644
index 00000000000..a702fef4f31
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr89242.C
@@ -0,0 +1,15 @@
+// { dg-do compile }
+// { dg-options "-fno-rerun-cse-after-loop -ftrapv -fno-tree-loop-optimize -fdelete-dead-exceptions -fno-forward-propagate -fnon-call-exceptions -O2" }
+
+void bar (int n, char *p)
+{
+  try
+    {
+      n++;
+      for (int i = 0; i < n - 1; i++)
+	p[i];
+    }
+  catch (...)
+    {}
+}
+