va_list: arc

[Richard Henderson]

I bet no one's seen one of these running in a coon's age.


r~


        * arc.h (EXPAND_BUILTIN_VA_START): New.
        (EXPAND_BUILTIN_VA_ARG): New.
        * arc.c (arc_setup_incoming_varargs): Set alias set of 
        varargs save area.
        (arc_va_start): New.
        (arc_va_arg): New.

Index: arc/arc.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/config/arc/arc.c,v
retrieving revision 1.6
diff -c -p -d -r1.6 arc.c
*** arc.c	1998/12/16 21:01:17	1.6
--- arc.c	1999/07/26 05:56:08
*************** arc_double_limm_p (value)
*** 751,757 ****
  
     We do things a little weird here.  We're supposed to only allocate space
     for the anonymous arguments.  However we need to keep the stack eight byte
!    aligned.  So we round the space up if necessary, and leave it to va-arc.h
     to compensate.  */
  
  void
--- 751,757 ----
  
     We do things a little weird here.  We're supposed to only allocate space
     for the anonymous arguments.  However we need to keep the stack eight byte
!    aligned.  So we round the space up if necessary, and leave it to va_start
     to compensate.  */
  
  void
*************** arc_setup_incoming_varargs (cum, mode, t
*** 789,794 ****
--- 789,796 ----
  			  plus_constant (arg_pointer_rtx,
  					 FIRST_PARM_OFFSET (0)
  					 + align_slop * UNITS_PER_WORD));
+       MEM_ALIAS_SET (regblock) = get_varargs_alias_set ();
+ 
        move_block_from_reg (first_reg_offset, regblock,
  			   MAX_ARC_PARM_REGS - first_reg_offset,
  			   ((MAX_ARC_PARM_REGS - first_reg_offset)
*************** arc_ccfsm_record_branch_deleted ()
*** 2200,2203 ****
--- 2202,2292 ----
       cc setter and user.  We need to undo the effect of calling record_cc_ref
       for the just deleted branch.  */
    current_insn_set_cc_p = last_insn_set_cc_p;
+ }
+ 
+ void
+ arc_va_start (stdarg_p, valist, nextarg)
+      int stdarg_p;
+      tree valist;
+      rtx nextarg;
+ {
+   /* See arc_setup_incoming_varargs for reasons for this oddity.  */
+   if (current_function_args_info < 8
+       && (current_function_args_info & 1))
+     nextarg = plus_constant (nextarg, UNITS_PER_WORD);
+ 
+   std_expand_builtin_va_start (stdarg_p, valist, nextarg);
+ }
+ 
+ rtx
+ arc_va_arg (valist, type)
+      tree valist, type;
+ {
+   rtx addr_rtx;
+   tree addr, incr;
+   tree type_ptr = build_pointer_type (type);
+ 
+   /* All aggregates are passed by reference.  All scalar types larger
+      than 8 bytes are passed by reference.  */
+ 
+   if (AGGREGATE_TYPE_P (type) || int_size_in_bytes (type) > 8)
+     {
+       tree type_ptr_ptr = build_pointer_type (type_ptr);
+ 
+       addr = build (INDIRECT_REF, type_ptr,
+ 		    build (NOP_EXPR, type_ptr_ptr, valist));
+ 
+       incr = build (PLUS_EXPR, TREE_TYPE (valist),
+ 		    valist, build_int_2 (UNITS_PER_WORD, 0));
+     }
+   else
+     {
+       HOST_WIDE_INT align, rounded_size;
+ 
+       /* Compute the rounded size of the type.  */
+       align = PARM_BOUNDARY / BITS_PER_UNIT;
+       rounded_size = (((TREE_INT_CST_LOW (TYPE_SIZE (type)) / BITS_PER_UNIT
+ 			+ align - 1) / align) * align);
+ 
+       /* Align 8 byte operands.  */
+       addr = valist;
+       if (TYPE_ALIGN (type) > BITS_PER_WORD)
+ 	{
+ 	  /* AP = (TYPE *)(((int)AP + 7) & -8)  */
+ 
+ 	  addr = build (NOP_EXPR, integer_type_node, valist);
+ 	  addr = fold (build (PLUS_EXPR, integer_type_node, addr,
+ 			      build_int_2 (7, 0)));
+ 	  addr = fold (build (BIT_AND_EXPR, integer_type_node, addr,
+ 			      build_int_2 (-8, 0)));
+ 	  addr = fold (build (NOP_EXPR, TREE_TYPE (valist), addr));
+ 	}
+ 
+       /* The increment is always rounded_size past the aligned pointer.  */
+       incr = fold (build (PLUS_EXPR, TREE_TYPE (addr), addr,
+ 			  build_int_2 (rounded_size, 0)));
+ 
+       /* Adjust the pointer in big-endian mode.  */
+       if (BYTES_BIG_ENDIAN)
+ 	{
+ 	  HOST_WIDE_INT adj;
+ 	  adj = TREE_INT_CST_LOW (TYPE_SIZE (type)) / BITS_PER_UNIT;
+ 	  if (rounded_size > align)
+ 	    adj = rounded_size;
+ 
+ 	  addr = fold (build (PLUS_EXPR, TREE_TYPE (addr), addr,
+ 			      build_int_2 (rounded_size - adj, 0)));
+ 	}
+     }
+ 
+   /* Evaluate the data address.  */
+   addr_rtx = expand_expr (addr, NULL_RTX, Pmode, EXPAND_NORMAL);
+   addr_rtx = copy_to_reg (addr_rtx);
+   
+   /* Compute new value for AP.  */
+   incr = build (MODIFY_EXPR, TREE_TYPE (valist), valist, incr);
+   TREE_SIDE_EFFECTS (incr) = 1;
+   expand_expr (incr, const0_rtx, VOIDmode, EXPAND_NORMAL);
+ 
+   return addr_rtx;
  }
Index: arc/arc.h
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/config/arc/arc.h,v
retrieving revision 1.11
diff -c -p -d -r1.11 arc.h
*** arc.h	1998/12/16 21:01:18	1.11
--- arc.h	1999/07/26 05:56:08
*************** enum arc_function_type {
*** 1640,1642 ****
--- 1640,1651 ----
  ((TYPE) == ARC_FUNCTION_ILINK1 || (TYPE) == ARC_FUNCTION_ILINK2)
  /* Compute the type of a function from its DECL.  */
  enum arc_function_type arc_compute_function_type ();
+ 
+ 
+ /* Implement `va_start' for varargs and stdarg.  */
+ #define EXPAND_BUILTIN_VA_START(stdarg, valist, nextarg) \
+   arc_va_start (stdarg, valist, nextarg)
+ 
+ /* Implement `va_arg'.  */
+ #define EXPAND_BUILTIN_VA_ARG(valist, type) \
+   arc_va_arg (valist, type)