re PR rtl-optimization/56847 ('-fpie' triggers - internal compiler error: in…

re PR rtl-optimization/56847 ('-fpie' triggers - internal compiler error: in gen_add2_insn, at optabs.c:4705)

2013-04-19  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/56847
	* lra-constraints.c (process_alt_operands): Discourage alternative
	with non-matche doffsettable memory constraint fro memory with
	known offset.

From-SVN: r198101

gcc/ChangeLog

+2013-04-19  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/56847
+	* lra-constraints.c (process_alt_operands): Discourage alternative
+	with non-matche doffsettable memory constraint fro memory with
+	known offset.
+
 2013-04-19  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/56982

gcc/lra-constraints.c

@@ -1978,8 +1978,15 @@ process_alt_operands (int only_alternative)
 			      (op, this_alternative) == NO_REGS))))
 		reject += LRA_MAX_REJECT;
 
-	      if (! ((const_to_mem && constmemok)
-		     || (MEM_P (op) && offmemok)))
+	      if (MEM_P (op) && offmemok)
+		{
+		  /* If we know offset and this non-offsetable memory,
+		     something wrong with this memory and it is better
+		     to try other memory possibilities.  */
+		  if (MEM_OFFSET_KNOWN_P (op))
+		    reject += LRA_MAX_REJECT;
+		}
+	      else if (! (const_to_mem && constmemok))
 		{
 		  /* We prefer to reload pseudos over reloading other
 		     things, since such reloads may be able to be

gcc/testsuite/ChangeLog

+2013-04-19  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/56847
+	* gcc.dg/pr56847.c: New test.
+
 2013-04-19  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/56982

gcc/testsuite/gcc.dg/pr56847.c

+/* PR rtl-optimization/56847 */
+/* { dg-do compile { target pie } } */
+/* { dg-options "-O2 -fpie" } */
+
+struct S { long int a, b; } e;
+__thread struct S s;
+
+void
+foo (void)
+{
+  s = e;
+}