Minor tweak to SPARC back-end

[Eric Botcazou <ebotcazou at libertysurf dot fr>]

The patch renames SIBCALL_SLOT_EMPTY_P into LEAF_SIBCALL_SLOT_RESERVED_P 
(modulo a negation) and tweaks output_restore to let it accept a PATTERN 
instead of the whole INSN.

Bootstrapped/regtested on sparc64-sun-solaris2.9 and sparc-sun-solaris2.8.  
I also verified that there is no change in the gcc.c-torture/compile 
testsuite at -O2.

Applied to mainline.


2004-07-04  Eric Botcazou  <ebotcazou@libertysurf.fr>

	* config/sparc/sparc.c (SIBCALL_SLOT_EMPTY_P): Rename
	into LEAF_SIBCALL_SLOT_RESERVED_P after negation.
	(eligible_for_sibcall_delay): Adjust use of SIBCALL_SLOT_EMPTY_P.
	(output_restore): Change parameter from 'insn' to 'pat'.
	(output_return): Adjust call to output_restore.
	(output_sibcall): Adjust use of SIBCALL_SLOT_EMPTY_P.
	Adjust call to output_restore.


-- 
Eric Botcazou

Index: config/sparc/sparc.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/sparc/sparc.c,v
retrieving revision 1.307
diff -c -p -r1.307 sparc.c
*** config/sparc/sparc.c	30 Jun 2004 21:45:28 -0000	1.307
--- config/sparc/sparc.c	3 Jul 2004 07:21:00 -0000
*************** Boston, MA 02111-1307, USA.  */
*** 54,63 ****
     "or %o7,%g0,X; call Y; or X,%g0,%o7" always, so that it can be optimized.
     With sethi/jmp, neither 'as' nor 'ld' has an easy way how to find out if
     somebody does not branch between the sethi and jmp.  */
! #define SIBCALL_SLOT_EMPTY_P 0
  #else
! #define SIBCALL_SLOT_EMPTY_P \
!   ((TARGET_ARCH32 || TARGET_CM_MEDLOW) && ! flag_pic)
  #endif
  
  /* Global variables for machine-dependent things.  */
--- 54,63 ----
     "or %o7,%g0,X; call Y; or X,%g0,%o7" always, so that it can be optimized.
     With sethi/jmp, neither 'as' nor 'ld' has an easy way how to find out if
     somebody does not branch between the sethi and jmp.  */
! #define LEAF_SIBCALL_SLOT_RESERVED_P 1
  #else
! #define LEAF_SIBCALL_SLOT_RESERVED_P \
!   ((TARGET_ARCH64 && !TARGET_CM_MEDLOW) || flag_pic)
  #endif
  
  /* Global variables for machine-dependent things.  */
*************** eligible_for_sibcall_delay (rtx trial)
*** 2946,2952 ****
      {
        /* If the tail call is done using the call instruction,
  	 we have to restore %o7 in the delay slot.  */
!       if (! SIBCALL_SLOT_EMPTY_P)
  	return 0;
  
        /* %g1 is used to build the function address */
--- 2946,2952 ----
      {
        /* If the tail call is done using the call instruction,
  	 we have to restore %o7 in the delay slot.  */
!       if (LEAF_SIBCALL_SLOT_RESERVED_P)
  	return 0;
  
        /* %g1 is used to build the function address */
*************** sparc_asm_function_epilogue (FILE *file,
*** 4355,4371 ****
  /* Output a 'restore' instruction.  */
   
  static void
! output_restore (rtx insn)
  {
!   rtx operands[3], pat;
  
!   if (! insn)
      {
        fputs ("\t restore\n", asm_out_file);
        return;
      }
  
-   pat = PATTERN (insn);
    if (GET_CODE (pat) != SET)
      abort ();
  
--- 4355,4370 ----
  /* Output a 'restore' instruction.  */
   
  static void
! output_restore (rtx pat)
  {
!   rtx operands[3];
  
!   if (! pat)
      {
        fputs ("\t restore\n", asm_out_file);
        return;
      }
  
    if (GET_CODE (pat) != SET)
      abort ();
  
*************** output_return (rtx insn)
*** 4483,4489 ****
  	    {
  	      fprintf (asm_out_file, "\tjmp\t%%i7+%d\n",
  		       sparc_skip_caller_unimp ? 12 : 8);
! 	      output_restore (delay);
  	    }
  
  	  PATTERN (delay) = gen_blockage ();
--- 4482,4488 ----
  	    {
  	      fprintf (asm_out_file, "\tjmp\t%%i7+%d\n",
  		       sparc_skip_caller_unimp ? 12 : 8);
! 	      output_restore (pat);
  	    }
  
  	  PATTERN (delay) = gen_blockage ();
*************** output_sibcall (rtx insn, rtx call_opera
*** 4521,4527 ****
  	 register window.  We simply output the jump to the function and
  	 the insn in the delay slot (if any).  */
  
!       if (! SIBCALL_SLOT_EMPTY_P && delay_slot_filled_p)
  	abort();
  
        if (delay_slot_filled_p)
--- 4520,4526 ----
  	 register window.  We simply output the jump to the function and
  	 the insn in the delay slot (if any).  */
  
!       if (LEAF_SIBCALL_SLOT_RESERVED_P && delay_slot_filled_p)
  	abort();
  
        if (delay_slot_filled_p)
*************** output_sibcall (rtx insn, rtx call_opera
*** 4560,4572 ****
  	  if (! delay)
  	    abort ();
  
! 	  output_restore (delay);
  
  	  PATTERN (delay) = gen_blockage ();
  	  INSN_CODE (delay) = -1;
  	}
        else
! 	output_restore (0);
      }
  
    return "";
--- 4559,4571 ----
  	  if (! delay)
  	    abort ();
  
! 	  output_restore (PATTERN (delay));
  
  	  PATTERN (delay) = gen_blockage ();
  	  INSN_CODE (delay) = -1;
  	}
        else
! 	output_restore (NULL_RTX);
      }
  
    return "";