From: Richard Biener <rguenther@suse.de>
Date: Mon, 27 Mar 2017 12:52:13 +0000 (+0000)
Subject: re PR tree-optimization/80181 (ICE in set_lattice_value, at tree-ssa-ccp.c:505)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=819df7815634caf606a3d212ca4cba6a93acafd0;p=gcc.git

re PR tree-optimization/80181 (ICE in set_lattice_value, at tree-ssa-ccp.c:505)

2017-03-27  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/80181
	* tree-ssa-ccp.c (likely_value): UNDEFINED ^ X is UNDEFINED.

	* gcc.dg/torture/pr80181.c: New testcase.

From-SVN: r246500
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6296cdd33de..600d26476b8 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2017-03-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/80181
+	* tree-ssa-ccp.c (likely_value): UNDEFINED ^ X is UNDEFINED.
+
 2017-03-27  Claudiu Zissulescu  <claziss@synopsys.com>
 
 	* config/arc/predicates.md (move_double_src_operand): Replace the
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 184ccdb4712..bc302a8f757 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-03-27  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/80181
+	* gcc.dg/torture/pr80181.c: New testcase.
+
 2017-03-27  Claudiu Zissulescu  <claziss@synopsys.com>
 
 	* testsuite/gcc.target/arc/interrupt-4.c: New file.
diff --git a/gcc/testsuite/gcc.dg/torture/pr80181.c b/gcc/testsuite/gcc.dg/torture/pr80181.c
new file mode 100644
index 00000000000..896ca4fe0bd
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr80181.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+
+int
+nr (void)
+{
+}
+
+void
+it (int dl)
+{
+  int vp = 0;
+
+  for (;;)
+    {
+      dl = vp ^ nr ();
+      dl ^= vp;
+      vp = 1;
+    }
+}
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index cd238242c01..023018c8d33 100644
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -741,9 +741,11 @@ likely_value (gimple *stmt)
 	case PLUS_EXPR:
 	case MINUS_EXPR:
 	case POINTER_PLUS_EXPR:
+	case BIT_XOR_EXPR:
 	  /* Not MIN_EXPR, MAX_EXPR.  One VARYING operand may be selected.
 	     Not bitwise operators, one VARYING operand may specify the
-	     result completely.  Not logical operators for the same reason.
+	     result completely.
+	     Not logical operators for the same reason, apart from XOR.
 	     Not COMPLEX_EXPR as one VARYING operand makes the result partly
 	     not UNDEFINED.  Not *DIV_EXPR, comparisons and shifts because
 	     the undefined operand may be promoted.  */