Implement __builtin_return_address(0) for v850

[Nick Clifton]

Hi Richard,

: On Fri, Jan 05, 2001 at 04:00:03PM -0800, Nick Clifton wrote:
: > 	* config/v850/v850.c (struct machine_function): Define.
: > 	(v850_save_machine_status): New function.
: > 	(v850_restore_machine_status): New function.
: > 	(v850_return_addr): New function.
: > 	(v850_init_expanders): New function.
: 
: You really want init_machine_status and mark_machine_status.
: Moreover, you'll get gc errors without mark_machine_status.

Good point.

The patch below does this.

Cheers
	Nick


2001-01-08  Nick Clifton  <nickc@redhat.com>

	* config/v850/v850.c (ra_rtx): Delete.
        (v850_save_machine_status): Delete.
	(v850_restore_machine_status): Delete.
	(v850_init_machine_status): New function.
	(v850_mark_machine_status): New function.
	(v850_free_machine_status): New function.
	(v850_return_addr): Use ra_rtx field in machine structure.
	(v850_init_expanders): Use new functions.

Index: config/v850/v850.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/v850/v850.c,v
retrieving revision 1.36
diff -p -r1.36 v850.c
*** v850.c	2001/01/06 00:00:35	1.36
--- v850.c	2001/01/09 03:01:29
*************** Boston, MA 02111-1307, USA.  */
*** 47,60 ****
  #endif
  
  /* Function prototypes for stupid compilers:  */
! static void const_double_split
!   PARAMS ((rtx, HOST_WIDE_INT *, HOST_WIDE_INT *));
! static int  const_costs_int        PARAMS ((HOST_WIDE_INT, int));
! static void substitute_ep_register PARAMS ((rtx, rtx, int, int, rtx *, rtx *));
! static int  ep_memory_offset       PARAMS ((enum machine_mode, int));
! static void v850_set_data_area     PARAMS ((tree, v850_data_area));
! static void v850_save_machine_status    PARAMS ((struct function *));
! static void v850_restore_machine_status PARAMS ((struct function *));
  
  /* True if the current function has anonymous arguments.  */
  int current_function_anonymous_args;
--- 47,60 ----
  #endif
  
  /* Function prototypes for stupid compilers:  */
! static void const_double_split       PARAMS ((rtx, HOST_WIDE_INT *, HOST_WIDE_INT *));
! static int  const_costs_int          PARAMS ((HOST_WIDE_INT, int));
! static void substitute_ep_register   PARAMS ((rtx, rtx, int, int, rtx *, rtx *));
! static int  ep_memory_offset         PARAMS ((enum machine_mode, int));
! static void v850_set_data_area       PARAMS ((tree, v850_data_area));
! static void v850_init_machine_status PARAMS ((struct function *));
! static void v850_mark_machine_status PARAMS ((struct function *));
! static void v850_free_machine_status PARAMS ((struct function *));
  
  /* True if the current function has anonymous arguments.  */
  int current_function_anonymous_args;
*************** v850_va_arg (valist, type)
*** 2788,2796 ****
  }
  
  /* Functions to save and restore machine-specific function data.  */
- 
- static rtx ra_rtx;
- 
  struct machine_function
  {
    /* Records __builtin_return address.  */
--- 2788,2793 ----
*************** struct machine_function
*** 2798,2816 ****
  };
  
  static void
! v850_save_machine_status (p)
       struct function * p;
  {
    p->machine =
      (struct machine_function *) xcalloc (1, sizeof (struct machine_function));
!   p->machine->ra_rtx = ra_rtx;
  }
  
  static void
! v850_restore_machine_status (p)
       struct function * p;
  {
-   ra_rtx = p->machine->ra_rtx;
    free (p->machine);
    p->machine = NULL;
  }
--- 2795,2818 ----
  };
  
  static void
! v850_init_machine_status (p)
       struct function * p;
  {
    p->machine =
      (struct machine_function *) xcalloc (1, sizeof (struct machine_function));
! }
! 
! static void
! v850_mark_machine_status (p)
!      struct function * p;
! {
!   ggc_mark_rtx (p->machine->ra_rtx);
  }
  
  static void
! v850_free_machine_status (p)
       struct function * p;
  {
    free (p->machine);
    p->machine = NULL;
  }
*************** v850_return_addr (count)
*** 2825,2841 ****
    if (count != 0)
      return const0_rtx;
  
!   if (ra_rtx == NULL)
      {
        rtx init;
        
        /* No rtx yet.  Invent one, and initialize it for r31 (lp) in 
         the prologue.  */
!       ra_rtx = gen_reg_rtx (Pmode);
        
        init = gen_rtx_REG (Pmode, LINK_POINTER_REGNUM);
  
!       init = gen_rtx_SET (VOIDmode, ra_rtx, init);
  
        /* Emit the insn to the prologue with the other argument copies.  */
        push_topmost_sequence ();
--- 2827,2843 ----
    if (count != 0)
      return const0_rtx;
  
!   if (cfun->machine->ra_rtx == NULL)
      {
        rtx init;
        
        /* No rtx yet.  Invent one, and initialize it for r31 (lp) in 
         the prologue.  */
!       cfun->machine->ra_rtx = gen_reg_rtx (Pmode);
        
        init = gen_rtx_REG (Pmode, LINK_POINTER_REGNUM);
  
!       init = gen_rtx_SET (VOIDmode, cfun->machine->ra_rtx, init);
  
        /* Emit the insn to the prologue with the other argument copies.  */
        push_topmost_sequence ();
*************** v850_return_addr (count)
*** 2843,2850 ****
        pop_topmost_sequence ();
      }
  
!   debug_rtx (ra_rtx);
!   return ra_rtx;
  }
  
  /* Do anything needed before RTL is emitted for each function.  */
--- 2845,2851 ----
        pop_topmost_sequence ();
      }
  
!   return cfun->machine->ra_rtx;
  }
  
  /* Do anything needed before RTL is emitted for each function.  */
*************** v850_return_addr (count)
*** 2852,2859 ****
  void
  v850_init_expanders ()
  {
!   ra_rtx = NULL;
! 
!   save_machine_status    = v850_save_machine_status;
!   restore_machine_status = v850_restore_machine_status;
  }
--- 2853,2859 ----
  void
  v850_init_expanders ()
  {
!   init_machine_status = v850_init_machine_status;
!   mark_machine_status = v850_mark_machine_status;
!   free_machine_status = v850_free_machine_status;
  }