2005-01-03 Daniel Berlin <dberlin@dberlin.org>

	Fix PR debug/17924
	Fix PR debug/19191
	* dwarf2out.c (block_ultimate_origin): Follow decl origin if origin
	is a decl.
	* gimple-low.c (mark_blocks_with_used_vars): New function.
	(mark_blocks_with_used_subblocks): Ditto.
	(mark_used_blocks): Ditto.
	(pass_mark_used_blocks): New pass.
	* tree-inline.c: Include debug.h.
	(expand_call_inline): Call outlining_inline_function here.
	* tree-optimize.c (init_tree_optimization_passes): Add
	pass_mark_used_blocks.
	* tree-pass.h (pass_mark_used_blocks): New.
	* Makefile.in (tree-inline.o): Add debug.h dependency.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@92882 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 84 insertions, 0 deletions

diff --git a/gcc/gimple-low.c b/gcc/gimple-low.c
index c6f6f7611e2..ee57d9beda0 100644
--- a/gcc/gimple-low.c
+++ b/gcc/gimple-low.c
@@ -540,3 +540,87 @@ struct tree_opt_pass pass_remove_useless_vars =
   TODO_dump_func,			/* todo_flags_finish */
   0					/* letter */
 };
+
+/* Mark BLOCK used if it has a used variable in it, then recurse over it's
+   subblocks.  */
+
+static void
+mark_blocks_with_used_vars (tree block)
+{
+  tree var;
+  tree subblock;
+
+  if (!TREE_USED (block))
+    {
+      for (var = BLOCK_VARS (block);
+	   var;
+	   var = TREE_CHAIN (var))
+	{
+	  if (TREE_USED (var))
+	    {
+	      TREE_USED (block) = true;
+	      break;
+	    }
+	}
+    }
+  for (subblock = BLOCK_SUBBLOCKS (block);
+       subblock;
+       subblock = BLOCK_CHAIN (subblock))
+    mark_blocks_with_used_vars (subblock);
+}
+
+/* Mark BLOCK used if any of it's subblocks have the USED bit set, or it's
+   abstract origin is used.  */
+
+static bool
+mark_blocks_with_used_subblocks (tree block)
+{
+  tree subblock;
+ 
+  /* The block may have no variables, but still be used, if it's abstract
+     origin is used.  This occurs when we inline functions with no parameters
+     that call functions with no parameters or local vars (such as
+     dwarf2/dwarf-die7.c).  You end up with a block that has an abstract
+     origin, no variables, and nothing in the subblocks is used.  However, the
+     block is really used, because it's abstract origin was used.  */
+
+  if (BLOCK_ABSTRACT_ORIGIN (block))
+    {
+      if (TREE_USED (BLOCK_ABSTRACT_ORIGIN (block)))
+	TREE_USED (block) = true;
+    }
+
+  for (subblock = BLOCK_SUBBLOCKS (block);
+       subblock;
+       subblock = BLOCK_CHAIN (subblock))
+    TREE_USED (block) |= mark_blocks_with_used_subblocks (subblock);
+  return TREE_USED (block);
+}
+
+/* Mark the used attribute on blocks correctly.  */
+  
+static void
+mark_used_blocks (void)
+{
+  
+  mark_blocks_with_used_vars (DECL_INITIAL (current_function_decl));
+  mark_blocks_with_used_subblocks (DECL_INITIAL (current_function_decl));
+}
+
+
+struct tree_opt_pass pass_mark_used_blocks = 
+{
+  "blocks",				/* name */
+  NULL,					/* gate */
+  mark_used_blocks,			/* execute */
+  NULL,					/* sub */
+  NULL,					/* next */
+  0,					/* static_pass_number */
+  0,					/* tv_id */
+  0,					/* properties_required */
+  0,					/* properties_provided */
+  0,					/* properties_destroyed */
+  0,					/* todo_flags_start */
+  TODO_dump_func,			/* todo_flags_finish */
+  0					/* letter */
+};