except.c (expand_start_java_handler): Push a new binding level.

2004-06-29  Andrew Haley  <aph@redhat.com>

        * except.c (expand_start_java_handler): Push a new binding level.
        Don't build a TRY_CATCH_EXPR now, we'll do it later.  Call
        register_exception_range() to register where we'll do it.
        (expand_end_java_handler): Remove old bogus code.  Replace with
        new logic that simply builds TRY_CATCH_EXPRs and inserts them at
        the top of the expression we're curently building.
        (maybe_end_try): Delete.
        * decl.c (binding_level.exception_range): New field.
        (clear_binding_level): Add field exception_range.  Reformat.
        (poplevel): Call expand_end_java_handler().
        (poplevel): Call java_add_stmt only if functionbody is false.
        (maybe_poplevels): Don't call maybe_end_try() from here.
        (end_java_method): Clear no longer used trees in function decl.
        (register_exception_range): New function.
        * java-tree.h (register_exception_range, struct eh_range): Declare.

From-SVN: r83857

gcc/java/ChangeLog

+2004-06-29  Andrew Haley  <aph@redhat.com>
+
+	* except.c (expand_start_java_handler): Push a new binding level.
+	Don't build a TRY_CATCH_EXPR now, we'll do it later.  Call
+	register_exception_range() to register where we'll do it.
+	(expand_end_java_handler): Remove old bogus code.  Replace with
+	new logic that simply builds TRY_CATCH_EXPRs and inserts them at
+	the top of the expression we're curently building.
+	(maybe_end_try): Delete.
+	* decl.c (binding_level.exception_range): New field.
+	(clear_binding_level): Add field exception_range.  Reformat.
+	(poplevel): Call expand_end_java_handler().
+	(poplevel): Call java_add_stmt only if functionbody is false.
+	(maybe_poplevels): Don't call maybe_end_try() from here.
+	(end_java_method): Clear no longer used trees in function decl.
+	(register_exception_range): New function.
+	* java-tree.h (register_exception_range, struct eh_range): Declare.
+
 2004-06-28  Bryce McKinlay  <mckinlay@redhat.com>
 
 	* jcf-write.c (get_classfile_modifiers): Formatting fixes.

gcc/java/decl.c

@@ -314,6 +314,9 @@ struct binding_level GTY(())
     /* The statements in this binding level.  */
     tree stmts;
 
+    /* An exception range associated with this binding level.  */
+    struct eh_range * GTY((skip (""))) exception_range;
+
     /* Binding depth at which this level began.  Used only for debugging.  */
     unsigned binding_depth;
   };
@@ -341,8 +344,18 @@ static GTY(()) struct binding_level *global_binding_level;
 /* Binding level structures are initialized by copying this one.  */
 
 static const struct binding_level clear_binding_level
-  = {NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE,
-     NULL_BINDING_LEVEL, LARGEST_PC, 0, NULL_TREE, 0};
+= {
+    NULL_TREE, /* names */
+    NULL_TREE, /* shadowed */
+    NULL_TREE, /* blocks */
+    NULL_TREE, /* this_lock */
+    NULL_BINDING_LEVEL, /* level_chain */
+    LARGEST_PC, /* end_pc */
+    0, /* start_pc */
+    NULL, /* stmts */
+    NULL, /* exception_range */
+    0, /* binding_depth */
+  };
 
 #if 0
 /* A list (chain of TREE_LIST nodes) of all LABEL_DECLs in the function
@@ -1316,6 +1329,9 @@ poplevel (int keep, int reverse, int functionbody)
       TREE_TYPE (block) = void_type_node;
     }
 
+  if (current_binding_level->exception_range)
+    expand_end_java_handler (current_binding_level->exception_range);
+
   if (block != 0)
     {
       /* If any statements have been generated at this level, create a
@@ -1341,7 +1357,6 @@ poplevel (int keep, int reverse, int functionbody)
 	    
 	  bind =  build (BIND_EXPR, TREE_TYPE (block), BLOCK_VARS (block), 
 			 BLOCK_EXPR_BODY (block), block);
-
 	  BIND_EXPR_BODY (bind) = current_binding_level->stmts;
 	  
 	  if (BIND_EXPR_BODY (bind)
@@ -1448,7 +1463,9 @@ poplevel (int keep, int reverse, int functionbody)
       DECL_INITIAL (current_function_decl) = block;
       DECL_SAVED_TREE (current_function_decl) = bind;
     }
-  else if (block)
+  else 
+    {
+      if (block)
 	{
 	  if (!block_previously_created)
 	    current_binding_level->blocks
@@ -1465,6 +1482,7 @@ poplevel (int keep, int reverse, int functionbody)
 
       if (bind)
 	java_add_stmt (bind);
+    }
 
   if (block)
     TREE_USED (block) = 1;
@@ -1521,11 +1539,7 @@ maybe_poplevels (int pc)
 #endif
 
   while (current_binding_level->end_pc <= pc)
-    {
-      maybe_end_try (current_binding_level->start_pc, pc);
     poplevel (1, 0, 0);
-    }
-  maybe_end_try (0, pc);
 }
 
 /* Terminate any binding which began during the range beginning at
@@ -1781,6 +1795,14 @@ end_java_method (void)
   flag_unit_at_a_time = 0;
   finish_method (fndecl);
 
+  if (! flag_unit_at_a_time)
+    {
+      /* Nulling these fields when we no longer need them saves
+	 memory.  */
+      DECL_SAVED_TREE (fndecl) = NULL;
+      DECL_STRUCT_FUNCTION (fndecl) = NULL;
+      DECL_INITIAL (fndecl) = NULL_TREE;
+    }
   current_function_decl = NULL_TREE;
 }
 
@@ -1929,5 +1951,19 @@ get_stmts (void)
   return &current_binding_level->stmts;
 }
 
+/* Register an exception range as belonging to the current binding
+   level.  There may only be one: if there are more, we'll create more
+   binding levels.  However, each range can have multiple handlers,
+   and these are expanded when we call expand_end_java_handler().  */
+
+void
+register_exception_range (struct eh_range *range, int pc, int end_pc)
+{
+  if (current_binding_level->exception_range)
+    abort ();
+  current_binding_level->exception_range = range;
+  current_binding_level->end_pc = end_pc;
+  current_binding_level->start_pc = pc;      
+}
 
 #include "gt-java-decl.h"

gcc/java/except.c

@@ -40,7 +40,6 @@ The Free Software Foundation is independent of Sun Microsystems, Inc.  */
 #include "toplev.h"
 
 static void expand_start_java_handler (struct eh_range *);
-static void expand_end_java_handler (struct eh_range *);
 static struct eh_range *find_handler_in_range (int, struct eh_range *,
 					       struct eh_range *);
 static void link_handler (struct eh_range *, struct eh_range *);
@@ -305,13 +304,8 @@ expand_start_java_handler (struct eh_range *range)
   fprintf (stderr, "expand start handler pc %d --> %d\n",
 	   current_pc, range->end_pc);
 #endif /* defined(DEBUG_JAVA_BINDING_LEVELS) */
-  {
-    tree new = build (TRY_CATCH_EXPR, void_type_node, NULL, NULL);
-    TREE_SIDE_EFFECTS (new) = 1;
-    java_add_stmt (build_java_empty_stmt ());
-    range->stmt = java_add_stmt (new);
-  }
-		     
+  pushlevel (0);
+  register_exception_range (range,  range->start_pc, range->end_pc);
   range->expanded = 1;
 }
 
@@ -428,13 +422,11 @@ build_exception_object_ref (tree type)
 
 /* If there are any handlers for this range, isssue end of range,
    and then all handler blocks */
-static void
+void
 expand_end_java_handler (struct eh_range *range)
 {  
   tree handler = range->handlers;
-  tree compound = NULL;
 
-  force_poplevels (range->start_pc);  
   for ( ; handler != NULL_TREE; handler = TREE_CHAIN (handler))
     {
       /* For bytecode we treat exceptions a little unusually.  A
@@ -444,54 +436,17 @@ expand_end_java_handler (struct eh_range *range)
 	 extra (and difficult) work to get this to look like a
 	 gcc-style finally clause.  */
       tree type = TREE_PURPOSE (handler);
-
       if (type == NULL)
 	type = throwable_type_node;
-
       type = prepare_eh_table_type (type);
 
-      if (compound)
       {
-	  /* If we already have a COMPOUND there is more than one
-	     catch handler for this try block.  Wrap the
-	     TRY_CATCH_EXPR in operand 1 of COMPOUND with another
-	     TRY_CATCH_EXPR.  */
-	  tree inner_try_expr = TREE_OPERAND (compound, 1);
 	tree catch_expr 
 	  = build (CATCH_EXPR, void_type_node, type,
 		   build (GOTO_EXPR, void_type_node, TREE_VALUE (handler)));
-	  tree try_expr
-	    = build (TRY_CATCH_EXPR, void_type_node,
-		     inner_try_expr, catch_expr);
-	  TREE_OPERAND (compound, 1) = try_expr;
-	}
-      else
-	{
-	  tree *stmts = get_stmts ();
-	  tree outer;
-	  tree try_expr;
-	  compound = range->stmt;
-	  outer = TREE_OPERAND (compound, 0);
-	  try_expr = TREE_OPERAND (compound, 1);
-	  /* On the left of COMPOUND is the expresion to be evaluated
-	     before the try handler is entered; on the right is a
-	     TRY_FINALLY_EXPR with no operands as yet.  In the current
-	     statement list is an expression that we're going to move
-	     inside the try handler.  We'll create a new COMPOUND_EXPR
-	     with the outer context on the left and the TRY_FINALLY_EXPR
-	     on the right, then nullify both operands of COMPOUND, which
-	     becomes the final expression in OUTER.  This new compound
-	     expression replaces the current statement list.  */
-	  TREE_OPERAND (try_expr, 0) = *stmts;
-	  TREE_OPERAND (try_expr, 1)
-	    = build (CATCH_EXPR, void_type_node, type,
-		     build (GOTO_EXPR, void_type_node, TREE_VALUE (handler)));
-	  TREE_SIDE_EFFECTS (try_expr) = 1;
-	  TREE_OPERAND (compound, 0) = build_java_empty_stmt ();
-	  TREE_OPERAND (compound, 1) = build_java_empty_stmt ();
-	  compound 
-	    = build (COMPOUND_EXPR, TREE_TYPE (try_expr), outer, try_expr);
-	  *stmts = compound;
+	tree try_catch_expr = build (TRY_CATCH_EXPR, void_type_node,
+				     *get_stmts (), catch_expr);	
+	*get_stmts () = try_catch_expr;
       }
     }
 #if defined(DEBUG_JAVA_BINDING_LEVELS)
@@ -536,19 +491,3 @@ maybe_start_try (int start_pc, int end_pc)
   check_start_handlers (range, start_pc);
 }
 
-/* Emit any end-of-try-range ending at end_pc and starting before
-   start_pc. */
-
-void
-maybe_end_try (int start_pc, int end_pc)
-{
-  if (! doing_eh (1))
-    return;
-
-  while (current_range != NULL_EH_RANGE && current_range->end_pc <= end_pc
-	 && current_range->start_pc >= start_pc)
-    {
-      expand_end_java_handler (current_range);
-      current_range = current_range->outer;
-    }
-}

gcc/java/java-except.h

@@ -68,3 +68,4 @@ extern void maybe_end_try (int, int);
 extern void add_handler (int, int, tree, tree);
 extern void handle_nested_ranges (void);
 extern void expand_resume_after_catch (void);
+extern void expand_end_java_handler (struct eh_range *);

gcc/java/java-tree.h

@@ -1117,6 +1117,9 @@ struct lang_type GTY(())
 #define SEARCH_SUPER          2
 #define SEARCH_VISIBLE        4
 
+/* Defined in java-except.h  */
+struct eh_range;
+
 extern void java_parse_file (int);
 extern bool java_mark_addressable (tree);
 extern tree java_type_for_mode (enum machine_mode, int);
@@ -1345,6 +1348,7 @@ extern tree add_stmt_to_compound (tree, tree, tree);
 extern tree java_add_stmt (tree);
 extern tree java_add_local_var (tree decl);
 extern tree *get_stmts (void);
+extern void register_exception_range(struct eh_range *, int, int);
 
 extern void finish_method (tree);
 extern void java_expand_body (tree);