From: Jakub Jelinek <jakub@redhat.com>
Date: Fri, 31 May 2019 07:53:48 +0000 (+0200)
Subject: re PR tree-optimization/90671 (ICE on valid code at -Os and above with -g enabled... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6992d6fbf2ffdb4a5c78604fbf33ae95956fffdd;p=gcc.git

re PR tree-optimization/90671 (ICE on valid code at -Os and above with -g enabled in gsi_split_seq_after, at gimple-iterator.c:345)

	PR tree-optimization/90671
	* tree-ssa-threadupdate.c (ssa_create_duplicates): If
	template_block used to be empty on the first call, don't use
	gsi_split_seq_after and gsi_insert_seq_after, but remember whole
	seq with bb_seq and set it with set_bb_seq.

	* gcc.dg/torture/pr90671.c: New test.

From-SVN: r271802
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e3792c6ee85..5283feda9d5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2019-05-31  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/90671
+	* tree-ssa-threadupdate.c (ssa_create_duplicates): If
+	template_block used to be empty on the first call, don't use
+	gsi_split_seq_after and gsi_insert_seq_after, but remember whole
+	seq with bb_seq and set it with set_bb_seq.
+
 2019-05-31  Iain Sandoe  <iain@sandoe.co.uk>
 
 	* config/i386/darwin.h (ASM_OUTPUT_MAX_SKIP_ALIGN): New.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 341dc4c4ecc..c081448df40 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-05-31  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/90671
+	* gcc.dg/torture/pr90671.c: New test.
+
 2019-05-31  Iain Sandoe  <iain@sandoe.co.uk>
 
 	* g++.dg/cpp0x/pr84497.C: Require alias support.
diff --git a/gcc/testsuite/gcc.dg/torture/pr90671.c b/gcc/testsuite/gcc.dg/torture/pr90671.c
new file mode 100644
index 00000000000..5a99b9d9a84
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr90671.c
@@ -0,0 +1,16 @@
+/* PR tree-optimization/90671 */
+/* { dg-do compile } */
+/* { dg-additional-options "-w -g" } */
+
+int a;
+
+int
+main ()
+{
+  int b, c;
+  for (c = 0; c < 2; c++)
+    while (a)
+      if (b)
+	break;
+  return 0;
+}
diff --git a/gcc/tree-ssa-threadupdate.c b/gcc/tree-ssa-threadupdate.c
index d6315431774..a56ccfbaa8c 100644
--- a/gcc/tree-ssa-threadupdate.c
+++ b/gcc/tree-ssa-threadupdate.c
@@ -1142,12 +1142,25 @@ ssa_create_duplicates (struct redirection_data **slot,
       gimple_seq seq = NULL;
       if (gsi_stmt (local_info->template_last_to_copy)
 	  != gsi_stmt (gsi_last_bb (local_info->template_block)))
-	seq = gsi_split_seq_after (local_info->template_last_to_copy);
+	{
+	  if (gsi_end_p (local_info->template_last_to_copy))
+	    {
+	      seq = bb_seq (local_info->template_block);
+	      set_bb_seq (local_info->template_block, NULL);
+	    }
+	  else
+	    seq = gsi_split_seq_after (local_info->template_last_to_copy);
+	}
       create_block_for_threading (local_info->template_block, rd, 0,
 				  &local_info->duplicate_blocks);
       if (seq)
-	gsi_insert_seq_after (&local_info->template_last_to_copy,
-			      seq, GSI_SAME_STMT);
+	{
+	  if (gsi_end_p (local_info->template_last_to_copy))
+	    set_bb_seq (local_info->template_block, seq);
+	  else
+	    gsi_insert_seq_after (&local_info->template_last_to_copy,
+				  seq, GSI_SAME_STMT);
+	}
 
       /* Go ahead and wire up outgoing edges and update PHIs for the duplicate
 	 block.   */