Fix compile time warning caused by PIC_OFFSET_TABLE_REGNUM be INVALID_REGNUM

2014-09-23  Jiong Wang  <jiong.wang@arm.com>

gcc/
  * shrink-wrap.c (try_shrink_wrapping): Check PIC_OFFSET_TABLE_REGNUM not
    be INVALID_REGNUM.

From-SVN: r215533

gcc/ChangeLog

+2014-09-23  Jiong Wang  <jiong.wang@arm.com>
+
+	* shrink-wrap.c (try_shrink_wrapping): Check PIC_OFFSET_TABLE_REGNUM not
+	be INVALID_REGNUM.
+
 2014-09-23  Thomas Schwinge  <thomas@codesourcery.com>
 
 	* configure: Regenerate.

gcc/shrink-wrap.c

@@ -495,7 +495,7 @@ try_shrink_wrapping (edge *entry_edge, edge orig_entry_edge,
       if (frame_pointer_needed)
 	add_to_hard_reg_set (&set_up_by_prologue.set, Pmode,
 			     HARD_FRAME_POINTER_REGNUM);
-      if (pic_offset_table_rtx)
+      if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM)
 	add_to_hard_reg_set (&set_up_by_prologue.set, Pmode,
 			     PIC_OFFSET_TABLE_REGNUM);
       if (crtl->drap_reg)