re PR rtl-optimization/65980 (-fcompare-debug failure building Linux kernel)

	PR rtl-optimization/65980
	* jump.c (rtx_renumbered_equal_p) <case LABEL_REF>: Use
	next_nonnote_nondebug_insn instead of next_real_insn and
	skip over CODE_LABELs too.

	* gcc.dg/pr65980.c: New test.

From-SVN: r231672

gcc/ChangeLog

+2015-12-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/65980
+	* jump.c (rtx_renumbered_equal_p) <case LABEL_REF>: Use
+	next_nonnote_nondebug_insn instead of next_real_insn and
+	skip over CODE_LABELs too.
+
 2015-12-10  Jan Hubicka  <hubicka@ucw.cz>
 
 	* symtab.c (symtab_node::fixup_same_cpp_alias_visibility):

gcc/jump.c

@@ -1802,8 +1802,16 @@ rtx_renumbered_equal_p (const_rtx x, const_rtx y)
 
       /* Two label-refs are equivalent if they point at labels
 	 in the same position in the instruction stream.  */
-      return (next_real_insn (LABEL_REF_LABEL (x))
-	      == next_real_insn (LABEL_REF_LABEL (y)));
+      else
+	{
+	  rtx_insn *xi = next_nonnote_nondebug_insn (LABEL_REF_LABEL (x));
+	  rtx_insn *yi = next_nonnote_nondebug_insn (LABEL_REF_LABEL (y));
+	  while (xi && LABEL_P (xi))
+	    xi = next_nonnote_nondebug_insn (xi);
+	  while (yi && LABEL_P (yi))
+	    yi = next_nonnote_nondebug_insn (yi);
+	  return xi == yi;
+	}
 
     case SYMBOL_REF:
       return XSTR (x, 0) == XSTR (y, 0);

gcc/testsuite/ChangeLog

+2015-12-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/65980
+	* gcc.dg/pr65980.c: New test.
+
 2015-12-15  Martin Sebor  <msebor@redhat.com>
 
 	c++/42121

gcc/testsuite/gcc.dg/pr65980.c

+/* PR rtl-optimization/65980 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -fcompare-debug" } */
+
+typedef struct { int b; } A;
+void (*a) (int);
+int b;
+
+int
+foo (A *v)
+{
+  asm goto ("" : : "m" (v->b) : : l);
+  return 0;
+l:
+  return 1;
+}
+
+int
+bar (void)
+{
+  if (b)
+    {
+      if (foo (0) && a)
+	a (0);
+      return 0;
+    }
+  if (foo (0) && a)
+    a (0);
+  return 0;
+}