From: Richard Biener <rguenther@suse.de>
Date: Thu, 27 Nov 2014 09:57:13 +0000 (+0000)
Subject: re PR middle-end/64083 (ICE: in fix_loop_structure, at loop-init.c:252 compiling... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e311c2d89a3bb45fe65e384126699dbaa2f57fdf;p=gcc.git

re PR middle-end/64083 (ICE: in fix_loop_structure, at loop-init.c:252 compiling Linux Kernel)

2014-11-27  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/64083
	* tree-ssa-threadupdate.c (thread_through_all_blocks): Do not
	forcibly mark loop for removal the wrong way.

	* gcc.dg/torture/pr64083.c: New testcase.

From-SVN: r218115
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 999686f6ee1..71828c2299d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/64083
+	* tree-ssa-threadupdate.c (thread_through_all_blocks): Do not
+	forcibly mark loop for removal the wrong way.
+
 2014-11-27  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/63704
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5e671fa92fe..5fc10c2b794 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-11-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/64083
+	* gcc.dg/torture/pr64083.c: New testcase.
+
 2014-11-27  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/61634
diff --git a/gcc/testsuite/gcc.dg/torture/pr64083.c b/gcc/testsuite/gcc.dg/torture/pr64083.c
new file mode 100644
index 00000000000..3c3e5a6087a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr64083.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+
+int a, b;
+void
+fn1 ()
+{
+  int c = 0;
+  while (b)
+    {
+      switch (c)
+    case 1:
+	fn1 ();
+	if (a)
+	  c = 1;
+	b = 0;
+    }
+}
diff --git a/gcc/tree-ssa-threadupdate.c b/gcc/tree-ssa-threadupdate.c
index ca0b8bfdd4b..a8243aea68a 100644
--- a/gcc/tree-ssa-threadupdate.c
+++ b/gcc/tree-ssa-threadupdate.c
@@ -2428,16 +2428,8 @@ thread_through_all_blocks (bool may_peel_loop_headers)
 		/* Our path is still valid, thread it.  */
 	        if (e->aux)
 		  {
-		    struct loop *loop = (*path)[0]->e->dest->loop_father;
-
 		    if (thread_block ((*path)[0]->e->dest, false))
-		      {
-			/* This jump thread likely totally scrambled this loop.
-			   So arrange for it to be fixed up.  */
-			loop->header = NULL;
-			loop->latch = NULL;
-			e->aux = NULL;
-		      }
+		      e->aux = NULL;
 		    else
 		      {
 		        delete_jump_thread_path (path);