Re: [patch] Merge dwarf4 branch

[Cary Coutant <ccoutant at google dot com>]

Here's the updated patch with all changes we discussed except for the
hashing of member function linkage names. If grandfathering this patch
in under Stage 1 is still OK, would it be OK if we bring that change
in later as a bug fix in stage 3? I'd still like to give that a bit
more thought.

I added two new functions for outputting a signature: print_signature
and output_signature; changed is_symbol_die to call
is_declaration_die; and added checksum code for dw_val_class_data8.
The big change was in attr_checksum_ordered and die_checksum_ordered
-- your suggestion did make it much cleaner (thanks!).

Bootstrapped OK; testing is underway. Some testing by hand shows that
nothing is functionally different.

-cary


        Add support for comdat type sections for DWARF v4.  Merge from dwarf4
        branch.
        * dwarf2out.c (DWARF_TYPE_SIGNATURE_SIZE): New constant.
        (dw_die_ref): Define vector type.
        (enum dw_val_class): Add dw_val_class_data8.
        (struct dw_val_struct): Add v.val_data8.
        (comdat_type_node_ref): New type.
        (struct die_struct): Move die_symbol into a union; add new field
        die_type_node.  Change all uses.
        (comdat_type_node): New type.
        (skeleton_chain_node): New type.
        (DWARF_COMDAT_TYPE_UNIT_HEADER_SIZE): New constant.
        (comdat_type_list): New variable.
        (dwarf_tag_name): Add DW_TAG_type_unit.
        (dwarf_attr_name): Add DW_AT_signature.
        (add_AT_data8): New function.
        (replace_child): New function.
        (move_all_children): New function.
        (print_signature): New function.
        (print_die): Print signature information; add dw_val_class_data8.
        (attr_checksum): Support dw_val_class_data8.
        (CHECKSUM_STRING): Redefine for DWARF-4 to include
        trailing NULL byte.
        (CHECKSUM_SLEB128, CHECKSUM_ULEB128): New macros.
        (checksum_sleb128, checksum_uleb128): New functions.
        (checksum_die_context): New function.
        (loc_checksum_ordered): New function.
        (attr_checksum_ordered): New function.
        (struct checksum_attributes): New structure.
        (collect_checksum_attributes): New function.
        (die_checksum_ordered): New function.
        (generate_type_signature): New function.
        (same_dw_val_p): Add dw_val_class_data8.
        (is_symbol_die): Use new is_declaration_die function.
        (is_declaration_die): New function.
        (should_move_die_to_comdat): New function.
        (clone_die): New function.
        (clone_tree): New function.
        (clone_as_declaration): New function.
        (copy_declaration_context): New function.
        (generate_skeleton_ancestor_tree): New function.
        (generate_skeleton_bottom_up): New function.
        (generate_skeleton): New function.
        (remove_child_or_replace_with_skeleton): New function.
        (break_out_comdat_types): New function.
        (struct decl_table_entry): New type.
        (htab_decl_hash): New function.
        (htab_decl_eq): New function.
        (htab_decl_del): New function.
        (copy_ancestor_tree): New function.
        (copy_decls_walk): New function.
        (copy_decls_for_unworthy_types): New function.
        (build_abbrev_table): Don't assert on missing die_symbol when doing
        comdat type sections.
        (size_of_die): Use DW_FORM_sig8 for external references; Add
        dw_val_class_data8.
        (unmark_dies): Don't assert for unmarked dies when doing comdat
        type sections.
        (value_format): Support DW_FORM_sig8 and dw_val_class_data8.
        (output_signature): New function.
        (output_die): Likewise.
        (output_compilation_unit_header): Mark output as DWARF version 3
        even if generating DWARF 4.
        (output_comdat_type_unit): New function.
        (output_line_info): Mark output as DWARF version 3 even if generating
        DWARF 4.
        (dwarf2out_start_source_file): Don't do eliminate_dwarf2_dups with
        DWARF-4.
        (dwarf2out_end_source_file): Likewise.
        (prune_unused_types_walk_attribs): Don't follow references into
        comdat type sections.
        (prune_unused_types_mark): When generating type units, do not mark
        children of non-defining declarations of types; do mark children of
        type entries.
        (prune_unused_types): Process comdat type sections.
        (htab_ct_hash): New function.
        (htab_ct_eq): New function.
        (dwarf2out_finish): Move types to comdat sections when using DWARF-4.
        Add a pointer to the line table from type unit entries so
        DW_AT_decl_file has meaning.
        * varasm.c (default_elf_asm_named_section): Use identifier name as
        comdat key instead of lang hook.

Attachment: dwarf4-merge-patch-2.txt
Description: Text document