rtl.h (renumber_insns): New function.

* rtl.h (renumber_insns): New function.
	(remove_unnecessary_notes): Likewise.
	* emit-rtl.c (renumber_insns): Define.
	(remove_unncessary_notes): Likewise.
	* toplev.c (rest_of_compilation): Remove dead code.
	Use renumber_insns and remove_unncessary_notes.

From-SVN: r30385

gcc/ChangeLog

@@ -1,5 +1,12 @@
 Wed Nov  3 14:51:59 1999  Mark P. Mitchell  <mark@codesourcery.com>
 
+	* rtl.h (renumber_insns): New function.
+	(remove_unnecessary_notes): Likewise.
+	* emit-rtl.c (renumber_insns): Define.
+	(remove_unncessary_notes): Likewise.
+	* toplev.c (rest_of_compilation): Remove dead code.
+	Use renumber_insns and remove_unncessary_notes.
+
 	* gcse.c (struct null_pointer_info): New type.
 	(get_bitmap_width): New function.
 	(current_block): Remove.

gcc/emit-rtl.c

@@ -1897,6 +1897,23 @@ get_max_uid ()
 {
   return cur_insn_uid;
 }
+
+void
+renumber_insns ()
+{
+  rtx insn;
+  int old_max_uid = cur_insn_uid;
+
+  /* If there aren't that many instructions, then it's not really
+     worth renumbering them.  */
+  if (get_max_uid () < 25000)
+    return;
+
+  cur_insn_uid = 1;
+
+  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
+    INSN_UID (insn) = cur_insn_uid++;
+}
 
 /* Return the next insn.  If it is a SEQUENCE, return the first insn
    of the sequence.  */
@@ -2568,6 +2585,33 @@ reorder_insns_with_line_notes (from, to, after)
 			  NOTE_LINE_NUMBER (after_line),
 			  to);
 }
+
+/* Remove unncessary notes from the instruction stream.  */
+
+void
+remove_unncessary_notes ()
+{
+  rtx insn;
+  rtx next;
+  varray_type block_stack;
+
+  /* Remove NOTE_INSN_DELETED notes.  We must not remove the first
+     instruction in the function because the compiler depends on the
+     first instruction being a note.  */
+  for (insn = NEXT_INSN (get_insns ()); insn; insn = next)
+    {
+      /* Remember what's next.  */
+      next = NEXT_INSN (insn);
+
+      /* We're only interested in notes.  */
+      if (GET_CODE (insn) != NOTE)
+	continue;
+
+      if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED)
+	remove_insn (insn);
+    }
+}
+
 
 /* Emit an insn of given code and pattern
    at a specified place within the doubly-linked list.  */

gcc/toplev.c

@@ -3562,15 +3562,14 @@ rest_of_compilation (decl)
   register rtx insns;
   int start_time = get_run_time ();
   int tem;
-  /* Nonzero if we have saved the original DECL_INITIAL of the function,
-     to be restored after we finish compiling the function
-     (for use when compiling inline calls to this function).  */
-  tree saved_block_tree = 0;
-  /* Likewise, for DECL_ARGUMENTS.  */
-  tree saved_arguments = 0;
   int failure = 0;
   int rebuild_label_notes_after_reload;
 
+  /* First, remove any notes we don't need.  That will make iterating
+     over the instruction sequence faster, and allow the garbage
+     collector to reclaim the memory used by the notes.  */
+  remove_unncessary_notes ();
+
   /* If we are reconsidering an inline function
      at the end of compilation, skip the stuff for making it inline.  */
 
@@ -3792,6 +3791,13 @@ rest_of_compilation (decl)
   if (ggc_p)
     ggc_collect ();
 
+  /* Jump optimization, and the removal of NULL pointer checks, may
+     have reduced the number of instructions substantially.  CSE, and
+     future passes, allocate arrays whose dimensions involve the maximum
+     instruction UID, so if we can reduce the maximum UID we'll save big on
+     memory.  */
+  renumber_insns ();
+
   /* Perform common subexpression elimination.
      Nonzero value from `cse_main' means that jumps were simplified
      and some code may now be unreachable, so do
@@ -3834,6 +3840,10 @@ rest_of_compilation (decl)
 	  if (graph_dump_format != no_graph)
 	    print_rtl_graph_with_bb (dump_base_name, ".02.cse", insns);
 	}
+
+      /* The second pass of jump optimization is likely to have
+         removed a bunch more instructions.  */
+      renumber_insns ();
     }
 
   purge_addressof (insns);
@@ -4455,18 +4465,6 @@ rest_of_compilation (decl)
     sdbout_types (NULL_TREE);
 #endif
 
-  /* Put back the tree of subblocks and list of arguments
-     from before we copied them.
-     Code generation and the output of debugging info may have modified
-     the copy, but the original is unchanged.  */
-
-  if (saved_block_tree != 0)
-    {
-      DECL_INITIAL (decl) = saved_block_tree;
-      DECL_ARGUMENTS (decl) = saved_arguments;
-      DECL_ABSTRACT_ORIGIN (decl) = NULL_TREE;
-    }
-
   reload_completed = 0;
   flow2_completed = 0;
   no_new_pseudos = 0;