🚀 go-pugleaf

A bug report from brennan@baker.ds.boeing.COM shows that, under
optimization, "switch (*p++)" may branch to the wrong case in the
switch.  Here is a patch.

----------------------------------------------------------------------------
Thu Apr  9 09:50:26 1992  Chip Salzenberg  (chip at tct.com)

	* stmt.c (expand_end_case): Before using index expression,
	  take care to call copy_to_reg() and protect_from_queue().

Index: stmt.c
*************** expand_end_case (orig_index)
*** 3582,3591 ****
  	    }
  
  	  emit_queue ();
  	  do_pending_stack_adjust ();
  
- 	  index = protect_from_queue (index, 0);
- 	  if (GET_CODE (index) == MEM)
- 	    index = copy_to_reg (index);
  	  if (GET_CODE (index) == CONST_INT
  	      || TREE_CODE (index_expr) == INTEGER_CST)
--- 3582,3591 ----
  	    }
  
+ 	  if (GET_CODE (index) == MEM)
+ 	    index = copy_to_reg (index);
+ 	  index = protect_from_queue (index, 0);
  	  emit_queue ();
  	  do_pending_stack_adjust ();
  
  	  if (GET_CODE (index) == CONST_INT
  	      || TREE_CODE (index_expr) == INTEGER_CST)
*************** expand_end_case (orig_index)
*** 3662,3667 ****
  				      index_expr);
  	      index = expand_expr (index_expr, 0, VOIDmode, 0);
! 	      emit_queue ();
  	      index = protect_from_queue (index, 0);
  	      do_pending_stack_adjust ();
  
--- 3662,3671 ----
  				      index_expr);
  	      index = expand_expr (index_expr, 0, VOIDmode, 0);
! 
! 
! 	      if (GET_CODE (index) == MEM)
! 		index = copy_to_reg (index);
  	      index = protect_from_queue (index, 0);
+ 	      emit_queue ();
  	      do_pending_stack_adjust ();
  
*************** expand_end_case (orig_index)
*** 3681,3686 ****
  	      index = expand_expr (index_expr, 0, VOIDmode, 0);
  	      index = convert_to_mode (Pmode, index, 1);
! 	      emit_queue ();
  	      index = protect_from_queue (index, 0);
  	      do_pending_stack_adjust ();
  
--- 3685,3693 ----
  	      index = expand_expr (index_expr, 0, VOIDmode, 0);
  	      index = convert_to_mode (Pmode, index, 1);
! 
! 	      if (GET_CODE (index) == MEM)
! 		index = copy_to_reg (index);
  	      index = protect_from_queue (index, 0);
+ 	      emit_queue ();
  	      do_pending_stack_adjust ();
  
-- 
Chip Salzenberg at Teltronics/TCT  <chip@tct.com>, <73717.366@compuserve.com>
      "Informix 4GL is not a 4G, and it's barely an L."  -- John Tombs