[gcjx] Patch: FYI: wrap LABEL_DECLs

[Tom Tromey <tromey at redhat dot com>]

I'm checking this in on the gcjx branch.

You have to wrap a LABEL_DECL in a LABEL_EXPR in order to use it as a
statement.  I don't really get the rationale for this, but I comply.

I forgot to address the bytecode-lowering part of this problem.  The
bytecode lowering code hasn't really gotten much attention yet.  In
case it isn't obvious all of the tree-lowering code is alpha quality,
I basically wrote it all out and now I'm fixing bugs piecemeal.

Tom

# 
# patch "gcc/gcc/java/ChangeLog"
#  from [58e071fa98227b7f3d0ab3d00f4164858575f025]
#    to [35289bee2f06c4edb8cf706f38989eda28165595]
# 
# patch "gcc/gcc/java/tree.cc"
#  from [b845207e88959825c85c52cff2bba67992049336]
#    to [37e70463907e099df2c599ac8228aa5ba5ef1fae]
# 
--- gcc/gcc/java/ChangeLog
+++ gcc/gcc/java/ChangeLog
@@ -1,5 +1,14 @@
 2005-02-08  Tom Tromey  <tromey@redhat.com>
 
+	* tree.cc (visit_for): Use LABEL_EXPRs as statements.  Set
+	DECL_CONTEXT on labels.
+	(visit_do): Set DECL_CONTEXT on labels.
+	(visit_for_enhanced): Likewise.
+	(visit_for): Likewise.
+	(visit_label): Likewise.
+	(visit_switch_block): Likewise.
+	(visit_while): Likewise.
+
 	* tree.cc (build_array_reference): Correctly handle array's type.
 	* builtins.cc (map_type): Don't set TYPE_NAME for array types.
 	(lay_out_class): Correctly set type of "data" field of array
--- gcc/gcc/java/tree.cc
+++ gcc/gcc/java/tree.cc
@@ -461,7 +461,9 @@
 {
   // Some labels which we'll use later.
   tree test = build0 (LABEL_DECL, NULL_TREE);
+  DECL_CONTEXT (test) = current_block;
   tree done = build0 (LABEL_DECL, NULL_TREE);
+  DECL_CONTEXT (done) = current_block;
   target_map[dstmt] = std::make_pair (test, done);
 
   // Generate code for the expression and the body.
@@ -518,7 +520,9 @@
 				    const ref_variable_decl &var)
 {
   tree update_tree = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
+  DECL_CONTEXT (update_tree) = current_block;
   tree done_tree = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
+  DECL_CONTEXT (done_tree) = current_block;
   target_map[fstmt] = std::make_pair (update_tree, done_tree);
 
   tree body_tree = alloc_stmt_list ();
@@ -544,7 +548,9 @@
 			   const ref_stmt &update)
 {
   tree update_tree = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
+  DECL_CONTEXT (update_tree) = current_block;
   tree done_tree = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
+  DECL_CONTEXT (done_tree) = current_block;
   target_map[fstmt] = std::make_pair (update_tree, done_tree);
 
   save_tree saver (current_block, make_node (BLOCK));
@@ -570,14 +576,16 @@
   body->visit (this);
   tsi_link_after (&out, current, TSI_CONTINUE_LINKING);
 
-  tsi_link_after (&out, update_tree, TSI_CONTINUE_LINKING);
+  tsi_link_after (&out, build1 (LABEL_EXPR, void_type_node, update_tree),
+		  TSI_CONTINUE_LINKING);
   if (update)
     {
       update->visit (this);
       tsi_link_after (&out, current, TSI_CONTINUE_LINKING);
     }
 
-  tsi_link_after (&out, done_tree, TSI_CONTINUE_LINKING);
+  tsi_link_after (&out, build1 (LABEL_EXPR, void_type_node, done_tree),
+		  TSI_CONTINUE_LINKING);
 
   current = build3 (BIND_EXPR, void_type_node,
 		    BLOCK_VARS (current_block),
@@ -613,6 +621,7 @@
   if (label->get_break_target () == NULL)
     {
       tree brk = build0 (LABEL_DECL, NULL_TREE);
+      DECL_CONTEXT (brk) = current_block;
       target_map[label] = std::make_pair (NULL_TREE, brk);
 
       tree body_tree = alloc_stmt_list ();
@@ -689,6 +698,7 @@
   tree_stmt_iterator out = tsi_start (body_tree);
 
   tree label = build0 (LABEL_DECL, NULL_TREE);
+  DECL_CONTEXT (label) = current_block;
 
   std::list<ref_expression> labels = swblock->get_labels ();
   for (std::list<ref_expression>::const_iterator i = labels.begin ();
@@ -836,7 +846,9 @@
 			     const ref_stmt &body)
 {
   tree again = build0 (LABEL_DECL, NULL_TREE);
+  DECL_CONTEXT (again) = current_block;
   tree done = build0 (LABEL_DECL, NULL_TREE);
+  DECL_CONTEXT (done) = current_block;
   target_map[wstmt] = std::make_pair (again, done);
 
   // Create the body of the loop: first the 'again' label, then the