[cleanup] remove label_value_list, fix a comment

[Steven Bosscher <stevenb at suse dot de>]

Hi,

label_value_list looks like a relic from olden days.  It is never
set now, so the patch below removes it.

I also saw that we talk about some flag in common.opt that does not
even exist.

If no-one objects, I'll commit this in the near future.

Gr.
Steven



	* basic-block.h (label_value_list): Remove extern decl.
	* cfgrtl.c (label_value_list): Remove.
	(can_delete_label_p): Don't look at it.
	* cfgcleanup.c (cleanup_cfg): Don't free it.

	* common.opt: Don't refer to non-existing flag_alias_check.
Index: basic-block.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/basic-block.h,v
retrieving revision 1.262
diff -u -3 -p -r1.262 basic-block.h
--- basic-block.h       3 Jun 2005 19:03:23 -0000       1.262
+++ basic-block.h       3 Jun 2005 23:25:27 -0000
@@ -446,10 +446,6 @@ extern bool rediscover_loops_after_threa
 #define FOR_ALL_BB_FN(BB, FN) \
   for (BB = ENTRY_BLOCK_PTR_FOR_FUNCTION (FN); BB; BB = BB->next_bb)

-/* Special labels found during CFG build.  */
-
-extern GTY(()) rtx label_value_list;
-
 extern bitmap_obstack reg_obstack;

 /* Indexed by n, gives number of basic block that  (REG n) is used in.
Index: cfgcleanup.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cfgcleanup.c,v
retrieving revision 1.145
diff -u -3 -p -r1.145 cfgcleanup.c
--- cfgcleanup.c        17 May 2005 06:48:17 -0000      1.145
+++ cfgcleanup.c        3 Jun 2005 23:25:27 -0000
@@ -2132,8 +2132,6 @@ cleanup_cfg (int mode)
       delete_dead_jumptables ();
     }

-  /* Kill the data we won't maintain.  */
-  free_EXPR_LIST_list (&label_value_list);
   timevar_pop (TV_CLEANUP_CFG);

   return changed;
Index: cfgrtl.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cfgrtl.c,v
retrieving revision 1.173
diff -u -3 -p -r1.173 cfgrtl.c
--- cfgrtl.c    26 May 2005 18:14:38 -0000      1.173
+++ cfgrtl.c    3 Jun 2005 23:25:27 -0000
@@ -59,11 +59,6 @@ Software Foundation, 59 Temple Place - S
 #include "target.h"
 #include "cfgloop.h"

-/* The labels mentioned in non-jump rtl.  Valid during find_basic_blocks.  */
-/* ??? Should probably be using LABEL_NUSES instead.  It would take a
-   bit of surgery to be able to use or co-opt the routines in jump.  */
-rtx label_value_list;
-
 static int can_delete_note_p (rtx);
 static int can_delete_label_p (rtx);
 static void commit_one_edge_insertion (edge, int);
@@ -103,8 +98,7 @@ can_delete_label_p (rtx label)
   return (!LABEL_PRESERVE_P (label)
          /* User declared labels must be preserved.  */
          && LABEL_NAME (label) == 0
-         && !in_expr_list_p (forced_labels, label)
-         && !in_expr_list_p (label_value_list, label));
+         && !in_expr_list_p (forced_labels, label));
 }

 /* Delete INSN by patching it out.  Return the next insn.  */
Index: common.opt
===================================================================
RCS file: /cvs/gcc/gcc/gcc/common.opt,v
retrieving revision 1.72
diff -u -3 -p -r1.72 common.opt
--- common.opt  1 Jun 2005 18:19:06 -0000       1.72
+++ common.opt  3 Jun 2005 23:25:27 -0000
@@ -234,7 +234,6 @@ Common RejectNegative Joined UInteger
 ;   global variables.
 ; 2 if pointer arguments may not alias each other and may not
 ;   alias global variables.  True in Fortran.
-;   The value is ignored if flag_alias_check is 0.
 fargument-alias
 Common Report Var(flag_argument_noalias,0)
 Specify that arguments may alias each other and globals