Re: [C++ patch] Move FINAL flag to middle-end trees.

[Jan Hubicka <hubicka at ucw dot cz>]

> On 08/24/2013 05:18 AM, Jan Hubicka wrote:
> >In the next step I would like to introduce the DECL_CPP_CONSTRUCTOR/DESTRUCTOR macro.
> >The catch I run into is that these flags are tested on TEMPLATE_DECL so the middle-end
> >macro bombs on type checking.  I wonder what is best approach here.
> 
> I think fix the front end to use STRIP_TEMPLATE to make sure we're
> checking/setting the flag on a FUNCTION_DECL.

Thank you!
I did not know the FUNCTION_DECLs are already there.  The following patch seems
to work.  Of course if it seems cleaner, I can update the users of the CPP
macros into the expanded variants.  I want to have CPP in name in middle-end to
signify that we actually understand language specific properties of these
functions (so constructors/destructors in other languages probably don't
want to do that).

Bootstrapped/regtested ppc64-linux, OK?

	* tree.h (tree_decl_with_vis): Add cpp_constructor and cpp_destructor.
	(DECL_CPP_CONSTRUCTOR_P, DECL_CPP_DESTRUCTOR_P): New macros.

	* cp-tree.h (DECL_CONSTRUCTOR_P, DECL_DESTRUCTOR_P): Change to
	strip templates and set the middle-end flag.
Index: tree.h
===================================================================
--- tree.h	(revision 201977)
+++ tree.h	(working copy)
@@ -3232,8 +3232,12 @@ struct GTY(()) tree_decl_with_vis {
  /* Used by C++ only.  Might become a generic decl flag.  */
  unsigned shadowed_for_var_p : 1;
  /* Belong to FUNCTION_DECL exclusively.  */
+ unsigned cpp_constructor : 1;
+ /* Belong to FUNCTION_DECL exclusively.  */
+ unsigned cpp_destructor : 1;
+ /* Belong to FUNCTION_DECL exclusively.  */
  unsigned final : 1;
- /* 13 unused bits. */
+ /* 11 unused bits. */
 };
 
 extern tree decl_debug_expr_lookup (tree);
@@ -3483,6 +3487,18 @@ extern vec<tree, va_gc> **decl_debug_arg
 #define DECL_FUNCTION_VERSIONED(NODE)\
    (FUNCTION_DECL_CHECK (NODE)->function_decl.versioned_function)
 
+/* In FUNCTION_DECL, this is set if this function is a C++ constructor.
+   Devirtualization machinery uses this knowledge for determing type of the
+   object constructed.  Also we assume that constructor address is not
+   important.  */
+#define DECL_CPP_CONSTRUCTOR_P(NODE)\
+   (FUNCTION_DECL_CHECK (NODE)->decl_with_vis.cpp_constructor)
+
+/* In FUNCTION_DECL, this is set if this function is a C++ destructor.
+   Devirtualization machinery uses this to track types in destruction.  */
+#define DECL_CPP_DESTRUCTOR_P(NODE)\
+   (FUNCTION_DECL_CHECK (NODE)->decl_with_vis.cpp_destructor)
+
 /* In FUNCTION_DECL that represent an virtual method this is set when
    the method is final.  */
 #define DECL_FINAL_P(NODE)\
Index: cp/cp-tree.h
===================================================================
--- cp/cp-tree.h	(revision 201977)
+++ cp/cp-tree.h	(working copy)
@@ -2121,9 +2121,10 @@ struct GTY((variable_size)) lang_decl {
 #define SET_DECL_LANGUAGE(NODE, LANGUAGE) \
   (DECL_LANG_SPECIFIC (NODE)->u.base.language = (LANGUAGE))
 
-/* For FUNCTION_DECLs: nonzero means that this function is a constructor.  */
+/* For FUNCTION_DECLs and TEMPLATE_DECLs: nonzero means that this function
+   is a constructor.  */
 #define DECL_CONSTRUCTOR_P(NODE) \
-  (LANG_DECL_FN_CHECK (NODE)->constructor_attr)
+  DECL_CPP_CONSTRUCTOR_P (STRIP_TEMPLATE (NODE))
 
 /* Nonzero if NODE (a FUNCTION_DECL) is a constructor for a complete
    object.  */
@@ -2152,9 +2153,10 @@ struct GTY((variable_size)) lang_decl {
 #define DECL_MOVE_CONSTRUCTOR_P(NODE) \
   (DECL_CONSTRUCTOR_P (NODE) && move_fn_p (NODE))
 
-/* Nonzero if NODE is a destructor.  */
+/* Nonzero if NODE (a FUNCTION_DECL or TEMPLATE_DECL)
+   is a destructor.  */
 #define DECL_DESTRUCTOR_P(NODE)				\
-  (LANG_DECL_FN_CHECK (NODE)->destructor_attr)
+  DECL_CPP_DESTRUCTOR_P (STRIP_TEMPLATE (NODE))
 
 /* Nonzero if NODE (a FUNCTION_DECL) is a destructor, but not the
    specialized in-charge constructor, in-charge deleting constructor,