re PR rtl-optimization/57968 (MODE_EXIT switches inserted too early)

        PR rtl-optimization/57968
        * mode-switching.c (create_pre_exit): Allow instructions that
        don't set a return register to need a non-exit mode.

From-SVN: r201225

gcc/ChangeLog

+2013-07-24  Joern Rennecke  <joern.rennecke@embecosm.com>
+
+	PR rtl-optimization/57968
+	* mode-switching.c (create_pre_exit): Allow instructions that
+	don't set a return register to need a non-exit mode.
+
 2013-07-24  Bill Schmidt  <wschmidt@vnet.linux.ibm.com>
 	    Anton Blanchard <anton@au1.ibm.com>
 

gcc/mode-switching.c

@@ -330,12 +330,10 @@ create_pre_exit (int n_entities, int *entity_map, const int *num_modes)
 			break;
 		      }
 		    if (!targetm.calls.function_value_regno_p (copy_start))
-		      {
-			last_insn = return_copy;
-			continue;
-		      }
-		    copy_num
-		      = hard_regno_nregs[copy_start][GET_MODE (copy_reg)];
+		      copy_num = 0;
+		    else
+		      copy_num
+			= hard_regno_nregs[copy_start][GET_MODE (copy_reg)];
 
 		    /* If the return register is not likely spilled, - as is
 		       the case for floating point on SH4 - then it might
@@ -372,6 +370,11 @@ create_pre_exit (int n_entities, int *entity_map, const int *num_modes)
 			  forced_late_switch = 1;
 			break;
 		      }
+		    if (copy_num == 0)
+		      {
+			last_insn = return_copy;
+			continue;
+		      }
 
 		    if (copy_start >= ret_start
 			&& copy_start + copy_num <= ret_end)