re PR debug/42662 (invalid rtl sharing found in the insn)

	PR debug/42662
	* simplify-rtx.c (simplify_relational_operation_1): Avoid invalid rtx
	sharing when canonicalizing ({lt,ge}u (plus a b) b).

	* gcc.dg/pr42662.c: New test.

From-SVN: r155831

gcc/ChangeLog

 2010-01-12  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/42662
+	* simplify-rtx.c (simplify_relational_operation_1): Avoid invalid rtx
+	sharing when canonicalizing ({lt,ge}u (plus a b) b).
+
 	PR tree-optimization/42645
 	* tree-inline.c (processing_debug_stmt): Move earlier.  Make static.
 	(remap_ssa_name): If processing_debug_stmt and name wasn't found in

gcc/simplify-rtx.c

@@ -4046,7 +4046,8 @@ simplify_relational_operation_1 (enum rtx_code code, enum machine_mode mode,
       && rtx_equal_p (op1, XEXP (op0, 1))
       /* Don't recurse "infinitely" for (LTU/GEU (PLUS b b) b).  */
       && !rtx_equal_p (op1, XEXP (op0, 0)))
-    return simplify_gen_relational (code, mode, cmp_mode, op0, XEXP (op0, 0));
+    return simplify_gen_relational (code, mode, cmp_mode, op0,
+				    copy_rtx (XEXP (op0, 0)));
 
   if (op1 == const0_rtx)
     {

gcc/testsuite/ChangeLog

 2010-01-12  Jakub Jelinek  <jakub@redhat.com>
 
+	PR debug/42662
+	* gcc.dg/pr42662.c: New test.
+
 	PR tree-optimization/42645
 	* g++.dg/other/pr42645-1.C: New test.
 	* g++.dg/other/pr42645-2.C: New test.

gcc/testsuite/gcc.dg/pr42662.c

+/* PR debug/42662 */
+/* { dg-do compile } */
+/* { dg-options "-g -O2" } */
+
+struct S { unsigned long s[17]; };
+
+static inline void
+foo (struct S *r, struct S *a, unsigned n)
+{
+  unsigned b = n / 8;
+  r->s[0] = (b >= 1 ? : a->s[1 - b]);
+}
+
+static inline void
+bar (struct S *r, struct S *a)
+{
+  r->s[0] = a->s[0] << 1;
+}
+
+static inline void
+baz (struct S *r, struct S *a, struct S *b)
+{
+  unsigned c = 0;
+  int i;
+  for (i = 0; i < 3; ++i)
+    {
+      unsigned long d = a->s[i];
+      long e = d + b->s[i];
+      if (c)
+	++e == 0;
+      c = e < d;
+      r->s[i] = e;
+    }
+}
+
+void
+test (struct S *r, int s, int d)
+{
+  struct S u;
+  if (s)
+    {
+      bar (&u, r);
+      foo (r, r, 3);
+      baz (r, r, &u);
+    }
+  u.s[0] = d;
+  baz (r, r, &u);
+}