The problem is fixed by simply moving the code that skips insns that don't
set a part of the return value below the code that checks if the insn needs
a non-MODE_EXIT mode setting.
bootstrapped/regtested on i686-pc-linux-gnu
2013-07-24 Joern Rennecke <joern.renne...@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.
Index: mode-switching.c
===================================================================
--- mode-switching.c (revision 201202)
+++ mode-switching.c (working copy)
@@ -330,12 +330,10 @@ create_pre_exit (int n_entities, int *en
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 *en
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)
