THe final localized spilling patches. See the ChangeLog for details.

From-SVN: r23374

gcc/ChangeLog

+Tue Oct 27 23:32:34 1998  Bernd Schmidt <crux@pool.informatik.rwth-aachen.de>
+
+	* reload.h (struct insn_chain): Add need_operand_change element.
+	* reload1.c (new_insn_chain): Clear it.
+	(calculate_needs_all_insns): Set it; don't overload need_reload.
+	(reload_as_needed): Use it.
+
+	* reload.c (find_reloads_address): Use BASE_REG_CLASS instead of
+	reload_address_base_reg_class throughout.  Similar for INDEX_REG_CLASS
+	and reload_address_index_reg_class.
+	(find_reloads_address_1): Likewise.
+	* reload.h (reload_address_base_reg_class,
+	reload_address_index_reg_class): Don't declare.
+	* reload1.c (reg_old_renumber, pseudo_previous_regs,
+	pseudo_forbidden_regs, bad_spill_regs_global): New static variables.
+	(used_spill_regs): Now static.
+	(reload_address_base_reg_class, reload_address_index_reg_class,
+	regs_explicitly_used, counted_for_groups, counted_for_nongroups,
+	basic_block_needs, max_needs, group_size, group_mode, max_groups,
+	max_nongroups, max_needs_insn, max_groups_insn, max_nongroups_insn,
+	forbidden_regs):
+	Deleted variables.
+	(init_reload): Delete code to compute base/index reg classes.
+	(reload): Delete variable J.
+	Delete code to manage basic_block_needs.
+	Don't compute regs_explicitly_used.
+	Allocate, initialize and free reg_old_renumber, pseudo_forbidden_regs,
+	pseudo_previous_regs.
+	Initialize bad_spill_regs_global.
+	Don't call order_regs_for_reload here.
+	Don't initialize spill_reg_order and n_spills.
+	Don't forbid explicitly used regs to be used for spill regs.
+	Change main loop to infinite loop, with explicit break statements.
+	Make SOMETHING_CHANGED variable local to that loop.
+	Don't initialize max_needs, max_groups, max_nongroups, max_needs_insn,
+	max_groups_insn, max_nongroups_insn, group_size, group_mode.
+	Make sure spilled_speudos is cleared before calling spill_hard_reg or
+	new_spill_reg.
+	Don't call dump_needs.
+	Delete code to reset potential_reload_regs.
+	Delete code to terminate loop conditional on the global needs variables
+	showing no further needs.
+	(calculate_needs_all_insns): Return void.  All callers changed.
+	Initialize somehing_needs_elimination here, not in reload.
+	Delete avoid_return_reg kludge.
+	(calculate_needs): Lose AVOID_RETURN_REG and GLOBAL args, return void.
+	All callers changed.
+	Initialize the group_mode and group_size elements of the arg CHAIN.
+	Delete code to manage basic_block_needs.
+	Operate on elements of CHAIN instead of global variables.
+	Delete avoid_return_reg kludge.
+	(find_tworeg_group): Lose GLOBAL arg, take CHAIN arg, return void.
+	All callers changed.
+	Operate on elements of CHAIN instead of global variables.
+	Delete special SMALL_REGISTER_CLASSES code.
+	Delete spill_failure code; now in new_spill_reg.
+	(find_group): Lose GLOBAL arg, take CHAIN arg, return void.
+	All callers changed.
+	Operate on elements of CHAIN instead of global variables.
+	(maybe_mark_pseudo_spilled): New static function.
+	(find_reload_regs): Lose GLOBAL arg, take CHAIN arg, return void.
+	All callers changed.
+	Operate on elements of CHAIN instead of global variables.
+	Call order_regs_for_reload here, not in reload.
+	Initialize spill_reg_order and n_spills.
+	Simplify test whether an asm insn is involved.
+	Delete spill_failure code; now in new_spill_reg.
+	Call maybe_mark_pseudo_spilled for everything marked as live in
+	CHAIN.  Merge CHAIN's used_spill_regs into the global variable
+	used_spill_regs.
+	(dump_needs): Take CHAIN arg.  No longer static, to prevent the
+	compiler from optimizing this function (now unused) away.
+	Operate on elements of CHAIN instead of global variables.
+	(possible_group_p): Lose MAX_GROUPS arg, take CHAIN arg.  All callers
+	changed.
+	Operate on elements of CHAIN instead of global variables.
+	(count_possible_groups): Lose GROUP_SIZE, GROUP_MODE, MAX_GROUPS args,
+	take CHAIN arg.  All callers changed.
+	Operate on elements of CHAIN instead of global variables.
+	(new_spill_reg): Lose MAX_NEEDS, MAX_NONGROUPS, GLOBAL args, take
+	CHAIN, NONGROUP args.  Return void.  All callers changed.
+	Verify caller isn't trying to spill a pseudo.
+	Simplify test for illegal reg, just use bad_spill_regs.
+	Generate better error messages.
+	Operate on elements of CHAIN instead of global variables.
+	Mark spilled register in CHAIN's used_spill_regs element.
+	Don't call spill_hard_reg.
+	(spill_hard_reg): Lose GLOBAL arg, return void.  All callers changed.
+	Mark spilled hard regs in bad_spill_regs_global.
+	Mark affected pseudos in spilled_pseudos, but don't spill them.
+	(ior_hard_reg_set): New static function.
+	(finish_spills): Return int.  All callers changed.
+	Compute spill_reg_order, n_spills and spill_regs here.  Also update
+	regs_ever_live for regs used as spills.
+	For every pseudo in spilled_pseudos, spill it and mark the previous
+	hard reg it had in pseudo_previous_regs.  Compute which hard regs
+	arseudo): New static function.
+	(order_regs_for_reload): Take CHAIN arg.  All callers changed.
+	Initialize bad_spill_regs from bad_spill_regs_global, then merge any
+	hard registers explicitly used across the current insn into the set.
+	Compute hard_reg_n_uses taking only pseudos live across this insn
+	into account.
+	Tweak sorting of potential_reload_regs.
+	(compare_spill_regs): Delete function.
+	(reload_as_needed): Don't sort the spill_regs array, it's computed
+	in proper order in finish_spills.
+	Delete avoid_return_reg kludge.
+	Delete code to manage basic_block_needs.
+	(allocate_reload_reg): Minor speed/readability tweaks.
+	Operate on elements of CHAIN instead of global variables.
+	(choose_reload_regs): Lose AVOID_RETURN_REG arg.  All callers changed.
+	Delete avoid_return_reg kludge.
+	Initialize reload_reg_used from CHAIN's used_spill_regs element.
+	Delete unused label FAIL.
+	(reload_combine): Replce reload_address_index_reg_class with
+	INDEX_REGS.
+	Don't use used_spill_regs to determine information about lifetime of
+	hard regs.
+
 Tue Oct 27 13:15:02 1998  Nick Clifton  <nickc@cygnus.com>
 	
 	* toplev.c (display_help): Ignore empty target specific

gcc/reload.c

@@ -4623,7 +4623,7 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 	return 0;
 
       /* If we do not have one of the cases above, we must do the reload.  */
-      push_reload (ad, NULL_RTX, loc, NULL_PTR, reload_address_base_reg_class,
+      push_reload (ad, NULL_RTX, loc, NULL_PTR, BASE_REG_CLASS,
 		   GET_MODE (ad), VOIDmode, 0, 0, opnum, type);
       return 1;
     }
@@ -4712,7 +4712,7 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 	  /* Must use TEM here, not AD, since it is the one that will
 	     have any subexpressions reloaded, if needed.  */
 	  push_reload (tem, NULL_RTX, loc, NULL_PTR,
-		       reload_address_base_reg_class, GET_MODE (tem),
+		       BASE_REG_CLASS, GET_MODE (tem),
 		       VOIDmode, 0,
 		       0, opnum, type);
 	  return 1;
@@ -4745,15 +4745,15 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 	  /* Reload the displacement into an index reg.
 	     We assume the frame pointer or arg pointer is a base reg.  */
 	  find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1),
-				     reload_address_index_reg_class,
-				     GET_MODE (ad), opnum, type, ind_levels);
+				     INDEX_REG_CLASS, GET_MODE (ad), opnum,
+				     type, ind_levels);
 	}
       else
 	{
 	  /* If the sum of two regs is not necessarily valid,
 	     reload the sum into a base reg.
 	     That will at least work.  */
-	  find_reloads_address_part (ad, loc, reload_address_base_reg_class,
+	  find_reloads_address_part (ad, loc, BASE_REG_CLASS,
 				     Pmode, opnum, type, ind_levels);
 	}
       return 1;
@@ -4804,8 +4804,7 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 				plus_constant (XEXP (XEXP (ad, 0), 0),
 					       INTVAL (XEXP (ad, 1))),
 			   XEXP (XEXP (ad, 0), 1));
-      find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0),
-				 reload_address_base_reg_class,
+      find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS,
 				 GET_MODE (ad), opnum, type, ind_levels);
       find_reloads_address_1 (mode, XEXP (ad, 1), 1, &XEXP (ad, 1), opnum,
 			      type, 0, insn);
@@ -4829,8 +4828,7 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 				XEXP (XEXP (ad, 0), 0),
 				plus_constant (XEXP (XEXP (ad, 0), 1),
 					       INTVAL (XEXP (ad, 1))));
-      find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1),
-				 reload_address_base_reg_class,
+      find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1), BASE_REG_CLASS,
 				 GET_MODE (ad), opnum, type, ind_levels);
       find_reloads_address_1 (mode, XEXP (ad, 0), 1, &XEXP (ad, 0), opnum,
 			      type, 0, insn);
@@ -4874,8 +4872,7 @@ find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels, insn)
 	  loc = &XEXP (*memrefloc, 0);
 	}
 
-      find_reloads_address_part (ad, loc, reload_address_base_reg_class,
-				 Pmode, opnum, type,
+      find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, opnum, type,
 				 ind_levels);
       return 1;
     }
@@ -5287,9 +5284,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 		  x = XEXP (x, 0);
 		  reloadnum
 		    = push_reload (x, x, loc, loc,
-				   (context
-				    ? reload_address_index_reg_class
-				    : reload_address_base_reg_class),
+				   (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 				    GET_MODE (x), GET_MODE (x), 0, 0,
 				    opnum, RELOAD_OTHER);
 		}
@@ -5297,9 +5292,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 		{
 		  reloadnum
 		    = push_reload (x, NULL_RTX, loc, NULL_PTR,
-				   (context
-				    ? reload_address_index_reg_class
-				    : reload_address_base_reg_class),
+				   (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 				   GET_MODE (x), GET_MODE (x), 0, 0,
 				   opnum, type);
 		  reload_inc[reloadnum]
@@ -5345,9 +5338,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 				opnum, type, ind_levels, insn);
 
 	  reloadnum = push_reload (x, NULL_RTX, loc, NULL_PTR,
-				   (context
-				    ? reload_address_index_reg_class
-				    : reload_address_base_reg_class),
+				   (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 				   GET_MODE (x), VOIDmode, 0, 0, opnum, type);
 	  reload_inc[reloadnum]
 	    = find_inc_amount (PATTERN (this_insn), XEXP (x, 0));
@@ -5376,8 +5367,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
       find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0),
 			    opnum, ADDR_TYPE (type), ind_levels, insn);
       push_reload (*loc, NULL_RTX, loc, NULL_PTR,
-		   (context ? reload_address_index_reg_class
-		    : reload_address_base_reg_class),
+		   (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 		   GET_MODE (x), VOIDmode, 0, 0, opnum, type);
       return 1;
 
@@ -5387,10 +5377,8 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 
 	if (reg_equiv_constant[regno] != 0)
 	  {
-	    find_reloads_address_part (reg_equiv_constant[regno], loc, 
-				       (context
-					? reload_address_index_reg_class
-					: reload_address_base_reg_class),
+	    find_reloads_address_part (reg_equiv_constant[regno], loc,
+				       (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 				       GET_MODE (x), opnum, type, ind_levels);
 	    return 1;
 	  }
@@ -5400,9 +5388,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 	if (reg_equiv_mem[regno] != 0)
 	  {
 	    push_reload (reg_equiv_mem[regno], NULL_RTX, loc, NULL_PTR,
-			 (context
-			  ? reload_address_index_reg_class
-			  : reload_address_base_reg_class),
+			 (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 			 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
 	    return 1;
 	  }
@@ -5430,9 +5416,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 		  : REGNO_MODE_OK_FOR_BASE_P (regno, mode))))
 	  {
 	    push_reload (x, NULL_RTX, loc, NULL_PTR,
-			 (context
-			  ? reload_address_index_reg_class
-			  : reload_address_base_reg_class),
+			 (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 			 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
 	    return 1;
 	  }
@@ -5444,9 +5428,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 	if (regno_clobbered_p (regno, this_insn))
 	  {
 	    push_reload (x, NULL_RTX, loc, NULL_PTR,
-			 (context
-			  ? reload_address_index_reg_class
-			  : reload_address_base_reg_class),
+			 (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 			 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
 	    return 1;
 	  }
@@ -5467,9 +5449,7 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 		     : REGNO_MODE_OK_FOR_BASE_P (regno, mode)))
 		{
 		  push_reload (x, NULL_RTX, loc, NULL_PTR,
-			       (context
-				? reload_address_index_reg_class
-				: reload_address_base_reg_class),
+			       (context ? INDEX_REG_CLASS : BASE_REG_CLASS),
 			       GET_MODE (x), VOIDmode, 0, 0, opnum, type);
 		  return 1;
 		}
@@ -5478,9 +5458,8 @@ find_reloads_address_1 (mode, x, context, loc, opnum, type, ind_levels, insn)
 	     is larger than the class size, then reload the whole SUBREG.  */
 	  else
 	    {
-	      enum reg_class class = (context
-				      ? reload_address_index_reg_class
-				      : reload_address_base_reg_class);
+	      enum reg_class class = (context ? INDEX_REG_CLASS
+				      : BASE_REG_CLASS);
 	      if (CLASS_MAX_NREGS (class, GET_MODE (SUBREG_REG (x)))
 		  > reg_class_size[class])
 		{

gcc/reload.h

@@ -50,8 +50,6 @@ extern int memory_move_secondary_cost PROTO ((enum machine_mode, enum reg_class,
 /* Maximum number of reloads we can need.  */
 #define MAX_RELOADS (2 * MAX_RECOG_OPERANDS * (MAX_REGS_PER_ADDRESS + 1))
 
-extern enum reg_class reload_address_base_reg_class;
-extern enum reg_class reload_address_index_reg_class;
 extern rtx reload_in[MAX_RELOADS];
 extern rtx reload_out[MAX_RELOADS];
 extern rtx reload_in_reg[MAX_RELOADS];
@@ -205,6 +203,9 @@ struct insn_chain
 
   /* Nonzero if find_reloads said the insn requires reloading.  */
   unsigned int need_reload:1;
+  /* Nonzero if find_reloads needs to be run during reload_as_needed to
+     perform modifications on any operands.  */
+  unsigned int need_operand_change:1;
   /* Nonzero if eliminate_regs_in_insn said it requires eliminations.  */
   unsigned int need_elim:1;
   /* Nonzero if this insn was inserted by perform_caller_saves.  */