Re: [RFC, PATCH 2/n] IPA C++ refactoring

[Jan Hubicka <hubicka at ucw dot cz>]

> 
> Bootstrapped/regtested x86_64-linux
> 
> Ready for trunk?
> 
> gcc/ChangeLog:
> 2014-07-17  Martin Liska  <mliska@suse.cz>
> 
>   * cgraph.h (varpool_node):
>   (availability get_availability (void)):
>     created from cgraph_variable_initializer_availability
>   (inline varpool_node *ultimate_alias_target (availability *availability = NULL)
>     creted from: cgraph_variable_initializer_availability
>   (inline varpool_node *get_alias_target (void)): created from varpool_alias_target
>   (void finalize_named_section_flags (void)):
>     created from varpool_finalize_named_section_flags
>   (bool assemble_decl (void)): created from varpool_assemble_decl
>   (void analyze (void)): created from varpool_analyze_node
>   (bool call_for_node_and_aliases (bool (*callback) (varpool_node *, void *),
>     void *data, bool include_overwritable)): created fromvarpool_for_node_and_aliases
>   (void remove_initializer (void)): created from varpool_remove_initializer
>   (tree get_constructor (void)): created from varpool_get_constructor
>   (bool externally_visible_p (void)): created from varpool_externally_visible_p
>   (bool ctor_useable_for_folding_p (void)): created from varpool_ctor_useable_for_folding_p
>   (inline bool all_refs_explicit_p ()): created from varpool_all_refs_explicit_p
>   (inline bool can_remove_if_no_refs_p (void)): created from varpool_can_remove_if_no_refs
>   (static inline varpool_node *get (const_tree decl)): created from varpool_get_node
>   (static void finalize_decl (tree decl)): created from varpool_finalize_decl
>   (static bool output_variables (void)): created from varpool_output_variables
>   (static varpool_node * extra_name_alias (tree alias, tree decl)):
>     created from varpool_extra_name_alias
>   (static varpool_node * create_alias (tree, tree)): created from varpool_create_variable_alias
>   (static void dump_varpool (FILE *f)): created from dump_varpool
>   (static void DEBUG_FUNCTION debug_varpool (void)): created from debug_varpool
>   (static varpool_node *create_empty (void)): created from varpool_create_empty_node
>   (static varpool_node *symbol_for_decl (tree decl)): created from varpool_node_for_decl
>   (static varpool_node *symbol_for_asmname (tree asmname)): created from varpool_node_for_asm
>   (void assemble_aliases (void)): created from assemble_aliases
> 

> +  /* Dump given varpool node to F.  */
> +  void dump (FILE *f);
> +
> +  /* Dump given varpool node to stderr.  */
> +  void DEBUG_FUNCTION debug (void);
> +
> +  /* Remove variable from symbol table.  */
> +  void remove (void);
> +
> +  /* Return variable availability.  */
> +  availability get_availability (void);
> +
> +  /* For given variable pool node, walk the alias chain to return the function
> +     the variable is alias of. Do not walk through thunks.
> +     When AVAILABILITY is non-NULL, get minimal availability in the chain.  */
> +  inline varpool_node *ultimate_alias_target
> +    (availability *availability = NULL);
> +
> +  /* Return node that alias is aliasing.  */
> +  inline varpool_node *get_alias_target (void);
> +
> +  /* For variables in named sections make sure get_variable_section
> +     is called before we switch to those sections.  Then section
> +     conflicts between read-only and read-only requiring relocations
> +     sections can be resolved.  */
> +  void finalize_named_section_flags (void);

Quite special, so it should go bellow the other declarations.
> +
> +  /* Output one variable, if necessary.  Return whether we output it.  */
> +  bool assemble_decl (void);
> +
> +  void analyze (void);
> +
> +  /* Call calback on varpool symbol and aliases associated to varpool symbol.
> +     When INCLUDE_OVERWRITABLE is false, overwritable aliases and thunks are
> +     skipped. */
> +  bool call_for_node_and_aliases (bool (*callback) (varpool_node *, void *),
> +				  void *data,
> +				   bool include_overwritable);
> +
> +  /* Remove node initializer when it is no longer needed.  */
> +  void remove_initializer (void);
> +
> +  /* When doing LTO, read variable's constructor from disk if
> +     it is not already present.  */
> +  tree get_constructor (void);
> +
> +  /* Return true when variable should be considered externally visible.  */
> +  bool externally_visible_p (void);

We have flag and this helper function to set it.  Probably the comment should
mention that this is not to be used except for varpool maintenance code.
> +
> +  /* Return true if variable has constructor that can be used for folding.  */
> +  bool ctor_useable_for_folding_p (void);

Group it with get_constructor and move earlier in the list (probably basic manipulation
first, constructor next, aliases and random predicates last)
> +
> +  /* Return true when all references to variable must be visible
> +     in ipa_ref_list.
> +     i.e. if the variable is not externally visible or not used in some magic
> +     way (asm statement or such).
> +     The magic uses are all summarized in force_output flag.  */
> +  inline bool all_refs_explicit_p ();
> +
> +  /* Return true when variable can be removed from variable pool
> +     if all direct calls are eliminated.  */
> +  inline bool can_remove_if_no_refs_p (void);
> +
> +  /* Return varpool node for given symbol and check it is a function. */
> +  static inline varpool_node *get (const_tree decl);
> +
> +  /* Mark DECL as finalized.  By finalizing the declaration, frontend instruct
> +     the middle end to output the variable to asm file, if needed or externally
> +     visible.  */
> +  static void finalize_decl (tree decl);
> +
> +  /* Output all variables enqueued to be assembled.  */
> +  static bool output_variables (void);
> +
> +  /* Attempt to mark ALIAS as an alias to DECL.  Return TRUE if successful.
> +     Extra name aliases are output whenever DECL is output.  */
> +  static varpool_node * extra_name_alias (tree alias, tree decl);
create_extra_name_alias
> +
> +  /* Attempt to mark ALIAS as an alias to DECL.  Return TRUE if successful.
> +     Extra name aliases are output whenever DECL is output.  */
> +  static varpool_node * create_alias (tree, tree);
> +
> +  /* Dump the variable pool to F.  */
> +  static void dump_varpool (FILE *f);
> +
> +  /* Dump the variable pool to stderr.  */
> +  static void DEBUG_FUNCTION debug_varpool (void);
> +
> +  /* Allocate new callgraph node and insert it into basic data structures.  */
> +  static varpool_node *create_empty (void);
> +
> +  /* Return varpool node assigned to DECL.  Create new one when needed.  */
> +  static varpool_node *symbol_for_decl (tree decl);

This is equivalent of get_create in cgraph, so lets call it the same way.
> +
> +  /* Given an assembler name, lookup node.  */
> +  static varpool_node *symbol_for_asmname (tree asmname);

Also please double heck it match the cgraph equivalent.

OK with those changes.
Honza