tree-ssa-operands.h (push_stmt_changes, [...]): Delete.

2009-05-24  Paolo Bonzini  <bonzini@gnu.org>

	* tree-ssa-operands.h (push_stmt_changes, pop_stmt_changes,
	discard_stmt_changes): Delete.
	* tree-ssa-operands.c (scb_stack): Delete.
	(init_ssa_operands): Do not initialize it.
	(fini_ssa_operands): Do not free it.
	(push_stmt_changes, pop_stmt_changes, discard_stmt_changes): Delete.

	* tree-cfg.c (replace_uses_by): Replace pop_stmt_changes with 
	update_stmt, remove the others.  Fix comments.
	* tree-dfa.c (optimize_stack_restore): Likewise.
	* tree-ssa-forwprop.c (forward_propagate_addr_expr): Likewise.
	* tree-ssa-loop-ivopts.c (rewrite_use): Likewise.
	* tree-ssa-dce.c (eliminate_unnecessary_stmts): Likewise.
	* tree-ssa-ccp.c (optimize_stack_restore, execute_fold_all_builtins):
	Likewise.
	* tree-ssa-propagate.c (substitute_and_fold): Likewise.
	* tree-ssa-dom.c (propagate_rhs_into_lhs): Likewise.
	(dom_opt_finalize_block): Likewise, adjusting access to stmts_to_rescan.
	(optimize_stmt): Likewise, adjusting access to stmts_to_rescan.
	(stmts_to_rescan): Change item type to gimple.
	(tree_ssa_dominator_optimize): Change type of stmts_to_rescan.

From-SVN: r147831

gcc/ChangeLog

+2009-05-24  Paolo Bonzini  <bonzini@gnu.org>
+
+	* tree-ssa-operands.h (push_stmt_changes, pop_stmt_changes,
+	discard_stmt_changes): Delete.
+	* tree-ssa-operands.c (scb_stack): Delete.
+	(init_ssa_operands): Do not initialize it.
+	(fini_ssa_operands): Do not free it.
+	(push_stmt_changes, pop_stmt_changes, discard_stmt_changes): Delete.
+
+	* tree-cfg.c (replace_uses_by): Replace pop_stmt_changes with 
+	update_stmt, remove the others.  Fix comments.
+	* tree-dfa.c (optimize_stack_restore): Likewise.
+	* tree-ssa-forwprop.c (forward_propagate_addr_expr): Likewise.
+	* tree-ssa-loop-ivopts.c (rewrite_use): Likewise.
+	* tree-ssa-dce.c (eliminate_unnecessary_stmts): Likewise.
+	* tree-ssa-ccp.c (optimize_stack_restore, execute_fold_all_builtins):
+	Likewise.
+	* tree-ssa-propagate.c (substitute_and_fold): Likewise.
+	* tree-ssa-dom.c (propagate_rhs_into_lhs): Likewise.
+	(dom_opt_finalize_block): Likewise, adjusting access to stmts_to_rescan.
+	(optimize_stmt): Likewise, adjusting access to stmts_to_rescan.
+	(stmts_to_rescan): Change item type to gimple.
+	(tree_ssa_dominator_optimize): Change type of stmts_to_rescan.
+
 2009-05-24  Ira Rosen  <irar@il.ibm.com>
 
 	* doc/passes.texi (Tree-SSA passes): Document SLP pass.

gcc/tree-cfg.c

@@ -1289,9 +1289,6 @@ replace_uses_by (tree name, tree val)
 
   FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
     {
-      if (gimple_code (stmt) != GIMPLE_PHI)
-	push_stmt_changes (&stmt);
-
       FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
         {
 	  replace_exp (use, val);
@@ -1318,7 +1315,7 @@ replace_uses_by (tree name, tree val)
 	  if (cfgcleanup_altered_bbs)
 	    bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
 
-	  /* FIXME.  This should go in pop_stmt_changes.  */
+	  /* FIXME.  This should go in update_stmt.  */
 	  for (i = 0; i < gimple_num_ops (stmt); i++)
 	    {
 	      tree op = gimple_op (stmt, i);
@@ -1330,8 +1327,7 @@ replace_uses_by (tree name, tree val)
 	    }
 
 	  maybe_clean_or_replace_eh_stmt (stmt, stmt);
-
-	  pop_stmt_changes (&stmt);
+	  update_stmt (stmt);
 	}
     }
 

gcc/tree-dfa.c

@@ -651,11 +651,7 @@ get_virtual_var (tree var)
   return var;
 }
 
-/* Mark all the naked symbols in STMT for SSA renaming.
-   
-   NOTE: This function should only be used for brand new statements.
-   If the caller is modifying an existing statement, it should use the
-   combination push_stmt_changes/pop_stmt_changes.  */
+/* Mark all the naked symbols in STMT for SSA renaming.  */
 
 void
 mark_symbols_for_renaming (gimple stmt)

gcc/tree-ssa-ccp.c

@@ -3023,14 +3023,9 @@ optimize_stack_restore (gimple_stmt_iterator i)
     return NULL_TREE;
 
   stack_save_gsi = gsi_for_stmt (stack_save);
-  push_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
   rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0);
   if (!update_call_from_tree (&stack_save_gsi, rhs))
-    {
-      discard_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
     return NULL_TREE;
-    }
-  pop_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
 
   /* No effect, so the statement will be deleted.  */
   return integer_zero_node;
@@ -3252,8 +3247,6 @@ execute_fold_all_builtins (void)
 	    }
 
           old_stmt = stmt;
-	  push_stmt_changes (gsi_stmt_ptr (&i));
-
           if (!update_call_from_tree (&i, result))
 	    {
 	      gimplify_and_update_call_from_tree (&i, result);
@@ -3261,7 +3254,7 @@ execute_fold_all_builtins (void)
 	    }
 
 	  stmt = gsi_stmt (i);
-	  pop_stmt_changes (gsi_stmt_ptr (&i));
+	  update_stmt (stmt);
 
 	  if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt)
 	      && gimple_purge_dead_eh_edges (bb))

gcc/tree-ssa-dce.c

@@ -983,10 +983,9 @@ eliminate_unnecessary_stmts (void)
 			  fprintf (dump_file, "\n");
 			}
 		      
-		      push_stmt_changes (gsi_stmt_ptr (&gsi));
 		      gimple_call_set_lhs (stmt, NULL_TREE);
 		      maybe_clean_or_replace_eh_stmt (stmt, stmt);
-		      pop_stmt_changes (gsi_stmt_ptr (&gsi));
+		      update_stmt (stmt);
 		      release_ssa_name (name);
 		    }
 		  notice_special_calls (stmt);

gcc/tree-ssa-dom.c

@@ -134,7 +134,7 @@ static VEC(expr_hash_elt_t,heap) *avail_exprs_stack;
    expressions are removed from AVAIL_EXPRS.  Else we may change the
    hash code for an expression and be unable to find/remove it from
    AVAIL_EXPRS.  */
-static VEC(gimple_p,heap) *stmts_to_rescan;
+static VEC(gimple,heap) *stmts_to_rescan;
 
 /* Structure for entries in the expression hash table.  */
 
@@ -626,7 +626,7 @@ tree_ssa_dominator_optimize (void)
   avail_exprs = htab_create (1024, real_avail_expr_hash, avail_expr_eq, free_expr_hash_elt);
   avail_exprs_stack = VEC_alloc (expr_hash_elt_t, heap, 20);
   const_and_copies_stack = VEC_alloc (tree, heap, 20);
-  stmts_to_rescan = VEC_alloc (gimple_p, heap, 20);
+  stmts_to_rescan = VEC_alloc (gimple, heap, 20);
   need_eh_cleanup = BITMAP_ALLOC (NULL);
 
   /* Setup callbacks for the generic dominator tree walker.  */
@@ -742,7 +742,7 @@ tree_ssa_dominator_optimize (void)
   
   VEC_free (expr_hash_elt_t, heap, avail_exprs_stack);
   VEC_free (tree, heap, const_and_copies_stack);
-  VEC_free (gimple_p, heap, stmts_to_rescan);
+  VEC_free (gimple, heap, stmts_to_rescan);
   
   /* Free the value-handle array.  */
   threadedge_finalize_values ();
@@ -1047,17 +1047,16 @@ dom_opt_finalize_block (struct dom_walk_data *walk_data, basic_block bb)
 
   /* If we queued any statements to rescan in this block, then
      go ahead and rescan them now.  */
-  while (VEC_length (gimple_p, stmts_to_rescan) > 0)
+  while (VEC_length (gimple, stmts_to_rescan) > 0)
     {
-      gimple *stmt_p = VEC_last (gimple_p, stmts_to_rescan);
-      gimple stmt = *stmt_p;
+      gimple stmt = VEC_last (gimple, stmts_to_rescan);
       basic_block stmt_bb = gimple_bb (stmt);
 
       if (stmt_bb != bb)
 	break;
 
-      VEC_pop (gimple_p, stmts_to_rescan);
-      pop_stmt_changes (stmt_p);
+      VEC_pop (gimple, stmts_to_rescan);
+      update_stmt (stmt);
     }
 }
 
@@ -2130,7 +2129,6 @@ optimize_stmt (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
   
   update_stmt_if_modified (stmt);
   opt_stats.num_stmts++;
-  push_stmt_changes (gsi_stmt_ptr (&si));
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     {
@@ -2253,21 +2251,12 @@ optimize_stmt (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
 	}
     }
 
-  if (may_have_exposed_new_symbols)
-    {
   /* Queue the statement to be re-scanned after all the
      AVAIL_EXPRS have been processed.  The change buffer stack for
      all the pushed statements will be processed when this queue
      is emptied.  */
-      VEC_safe_push (gimple_p, heap, stmts_to_rescan, gsi_stmt_ptr (&si));
-    }
-  else
-    {
-      /* Otherwise, just discard the recently pushed change buffer.  If
-	 not, the STMTS_TO_RESCAN queue will get out of synch with the
-	 change buffer stack.  */
-      discard_stmt_changes (gsi_stmt_ptr (&si));
-    }
+  if (may_have_exposed_new_symbols)
+    VEC_safe_push (gimple, heap, stmts_to_rescan, gsi_stmt (si));
 }
 
 /* Search for an existing instance of STMT in the AVAIL_EXPRS table.
@@ -2565,8 +2554,6 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name
 	      print_gimple_stmt (dump_file, use_stmt, 0, dump_flags);
 	    }
 
-	  push_stmt_changes (&use_stmt);
-
 	  /* Propagate the RHS into this use of the LHS.  */
 	  FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 	    propagate_value (use_p, rhs);
@@ -2601,7 +2588,6 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name
 		  bitmap_set_bit (interesting_names, SSA_NAME_VERSION (result));
 		}
 
-	      discard_stmt_changes (&use_stmt);
 	      continue;
 	    }
 
@@ -2618,9 +2604,8 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name
 	  fold_stmt_inplace (use_stmt);
 
 	  /* Sometimes propagation can expose new operands to the
-	     renamer.  Note this will call update_stmt at the 
-	     appropriate time.  */
-	  pop_stmt_changes (&use_stmt);
+	     renamer.  */
+	  update_stmt (use_stmt);
 
 	  /* Dump details.  */
 	  if (dump_file && (dump_flags & TDF_DETAILS))

gcc/tree-ssa-forwprop.c

@@ -951,19 +951,17 @@ forward_propagate_addr_expr (tree name, tree rhs)
 
       {
 	gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
-	push_stmt_changes (&use_stmt);
 	result = forward_propagate_addr_expr_1 (name, rhs, &gsi,
 						single_use_p);
 	/* If the use has moved to a different statement adjust
-	   the update machinery.  */
+	   the update machinery for the old statement too.  */
 	if (use_stmt != gsi_stmt (gsi))
 	  {
-	    pop_stmt_changes (&use_stmt);
-	    use_stmt = gsi_stmt (gsi);
 	    update_stmt (use_stmt);
+	    use_stmt = gsi_stmt (gsi);
 	  }
-	else
-	  pop_stmt_changes (&use_stmt);
+
+	update_stmt (use_stmt);
       }
       all &= result;
 

gcc/tree-ssa-loop-ivopts.c

@@ -5304,8 +5304,6 @@ rewrite_use_compare (struct ivopts_data *data,
 static void
 rewrite_use (struct ivopts_data *data, struct iv_use *use, struct iv_cand *cand)
 {
-  push_stmt_changes (&use->stmt);
-
   switch (use->type)
     {
       case USE_NONLINEAR_EXPR:
@@ -5324,7 +5322,7 @@ rewrite_use (struct ivopts_data *data, struct iv_use *use, struct iv_cand *cand)
 	gcc_unreachable ();
     }
   
-  pop_stmt_changes (&use->stmt);
+  update_stmt (use->stmt);
 }
 
 /* Rewrite the uses using the selected induction variables.  */

gcc/tree-ssa-operands.c

@@ -147,12 +147,6 @@ static void get_expr_operands (gimple, tree *, int);
 /* Number of functions with initialized ssa_operands.  */
 static int n_initialized = 0;
 
-/* Stack of statements to change.  Every call to
-   push_stmt_changes pushes the stmt onto the stack.  Calls to
-   pop_stmt_changes pop a stmt off of the stack and compute the set
-   of changes for the popped statement.  */
-static VEC(gimple_p,heap) *scb_stack;
-
 /* Return the DECL_UID of the base variable of T.  */
 
 static inline unsigned
@@ -231,7 +225,6 @@ init_ssa_operands (void)
       build_vuse = NULL_TREE;
       build_vdef = NULL_TREE;
       bitmap_obstack_initialize (&operands_bitmap_obstack);
-      scb_stack = VEC_alloc (gimple_p, heap, 20);
     }
 
   gcc_assert (gimple_ssa_operands (cfun)->operand_memory == NULL);
@@ -257,11 +250,6 @@ fini_ssa_operands (void)
       VEC_free (tree, heap, build_uses);
       build_vdef = NULL_TREE;
       build_vuse = NULL_TREE;
-
-      /* The change buffer stack had better be empty.  */
-      gcc_assert (VEC_length (gimple_p, scb_stack) == 0);
-      VEC_free (gimple_p, heap, scb_stack);
-      scb_stack = NULL;
     }
 
   gimple_ssa_operands (cfun)->free_defs = NULL;
@@ -1329,62 +1317,6 @@ debug_immediate_uses_for (tree var)
 }
 
 
-/* Push *STMT_P on the SCB_STACK.  This function is deprecated, do not
-   introduce new uses of it.  */
-
-void
-push_stmt_changes (gimple *stmt_p)
-{
-  gimple stmt = *stmt_p;
-
-  /* It makes no sense to keep track of PHI nodes.  */
-  if (gimple_code (stmt) == GIMPLE_PHI)
-    return;
-
-  VEC_safe_push (gimple_p, heap, scb_stack, stmt_p);
-}
-
-/* Pop the top stmt from SCB_STACK and act on the differences between
-   what was recorded by push_stmt_changes and the current state of
-   the statement.  This function is deprecated, do not introduce
-   new uses of it.  */
-
-void
-pop_stmt_changes (gimple *stmt_p)
-{
-  gimple *stmt2_p, stmt = *stmt_p;
-
-  /* It makes no sense to keep track of PHI nodes.  */
-  if (gimple_code (stmt) == GIMPLE_PHI)
-    return;
-
-  stmt2_p = VEC_pop (gimple_p, scb_stack);
-  gcc_assert (stmt_p == stmt2_p);
-
-  /* Force an operand re-scan on the statement and mark any newly
-     exposed variables.  This also will mark the virtual operand
-     for renaming if necessary.  */
-  update_stmt (stmt);
-}
-
-/* Discard the topmost stmt from SCB_STACK.  This is useful
-   when the caller realized that it did not actually modified the
-   statement.  It avoids the expensive operand re-scan.
-   This function is deprecated, do not introduce new uses of it.  */
-
-void
-discard_stmt_changes (gimple *stmt_p)
-{
-  gimple *stmt2_p, stmt = *stmt_p;
-  
-  /* It makes no sense to keep track of PHI nodes.  */
-  if (gimple_code (stmt) == GIMPLE_PHI)
-    return;
-
-  stmt2_p = VEC_pop (gimple_p, scb_stack);
-  gcc_assert (stmt_p == stmt2_p);
-}
-
 /* Unlink STMTs virtual definition from the IL by propagating its use.  */
 
 void

gcc/tree-ssa-operands.h

@@ -114,10 +114,6 @@ extern void debug_decl_set (bitmap);
 
 extern bool ssa_operands_active (void);
 
-extern void push_stmt_changes (gimple *);
-extern void pop_stmt_changes (gimple *);
-extern void discard_stmt_changes (gimple *);
-
 extern void unlink_stmt_vdef (gimple);
 
 enum ssa_op_iter_type {

gcc/tree-ssa-propagate.c

@@ -1109,9 +1109,6 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
 	      continue;
 	    }
 
-	  /* Record the state of the statement before replacements.  */
-	  push_stmt_changes (gsi_stmt_ptr (&i));
-
 	  /* Replace the statement with its folded version and mark it
 	     folded.  */
 	  did_replace = false;
@@ -1172,14 +1169,9 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
               }
 
 	      /* Determine what needs to be done to update the SSA form.  */
-	      pop_stmt_changes (gsi_stmt_ptr (&i));
+	      update_stmt (stmt);
 	      something_changed = true;
 	    }
-	  else
-	    {
-	      /* The statement was not modified, discard the change buffer.  */
-	      discard_stmt_changes (gsi_stmt_ptr (&i));
-	    }
 
 	  if (dump_file && (dump_flags & TDF_DETAILS))
 	    {