From: Richard Biener <rguenther@suse.de>
Date: Tue, 6 Oct 2015 12:34:15 +0000 (+0000)
Subject: re PR tree-optimization/67859 (ICE on valid code at -O2 and -O3 on x86_64-linux-gnu)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0580f6a1a8eba90a82c83b8341f94d25529b25e9;p=gcc.git

re PR tree-optimization/67859 (ICE on valid code at -O2 and -O3 on x86_64-linux-gnu)

2015-10-06  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/67859
	* tree-ssa-pre.c (create_expression_by_pieces): Properly
	discard not inserted stmts.

	* gcc.dg/torture/pr67859.c: New testcase.

From-SVN: r228519
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6afa6910260..eb02d8b6c1c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-06  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/67859
+	* tree-ssa-pre.c (create_expression_by_pieces): Properly
+	discard not inserted stmts.
+
 2015-10-06  Jonathan Wakely  <jwakely@redhat.com>
 
 	* doc/extend.texi (Template Instantiation): Reorder options and
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a931b24adc9..8b27d2ec97f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-10-06  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/67859
+	* gcc.dg/torture/pr67859.c: New testcase.
+
 2015-10-05  Kirill Yukhin  <kirill.yukhin@intel.com>
 
 	* gcc.target/i386/builtin_target.c: Add check for AES and PCLMUL.
diff --git a/gcc/testsuite/gcc.dg/torture/pr67859.c b/gcc/testsuite/gcc.dg/torture/pr67859.c
new file mode 100644
index 00000000000..259b3810f10
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr67859.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+
+int a, b, c;
+
+void
+fn1 ()
+{
+  b = c ? 0 : 1 << a;
+  b |= 0x9D7A5FD9;
+  for (;;)
+    {
+      int d = 1;
+      b &= (unsigned) d;
+    }
+}
diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c
index fb9ed02ec87..c5af63d8ca1 100644
--- a/gcc/tree-ssa-pre.c
+++ b/gcc/tree-ssa-pre.c
@@ -2897,11 +2897,16 @@ create_expression_by_pieces (basic_block block, pre_expr expr,
 
   folded = gimple_convert (&forced_stmts, exprtype, folded);
 
-  /* If everything simplified to an exisiting SSA name or constant just
-     return that.  */
-  if (gimple_seq_empty_p (forced_stmts)
-      || is_gimple_min_invariant (folded))
+  /* If there is nothing to insert, return the simplified result.  */
+  if (gimple_seq_empty_p (forced_stmts))
     return folded;
+  /* If we simplified to a constant return it and discard eventually
+     built stmts.  */
+  if (is_gimple_min_invariant (folded))
+    {
+      gimple_seq_discard (forced_stmts);
+      return folded;
+    }
 
   gcc_assert (TREE_CODE (folded) == SSA_NAME);