Function gc_build_histogram

src/ast/ast_gc_report.cpp:77–89

    }

    static void gc_build_histogram ( const gc_root & root, Histogram & histo ) {
        for ( auto node = root.gc_first; node; node = node->gc_next ) {
            uint16_t tag = node->gc_type_tag();
            const LineInfo * li = gc_node_at(node);
            string key;
            uint32_t line = 0;
            if ( li && li->fileInfo ) { key = li->fileInfo->name; line = li->line; }
            else { key = "<no source>"; }
            auto & fb = histo[key];
            fb.total.add(tag);
            fb.byLine[line].add(tag);
        }
    }

    // "[Expr 1200, TypeDecl 900]" — nonzero tags, descending by count.
    static void gc_format_breakdown ( const TagCounts & c, TextWriter & out ) {