source: src/CodeGen/LinkOnce.cc@ 5384793

//
// Cforall Version 1.0.0 Copyright (C) 2021 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// LinkOnce.cc -- Translate the cfa_linkonce attribute.
//
// Author           : Andrew Beach
// Created On       : Thur May 13 10:10:00 2021
// Last Modified By : Andrew Beach
// Last Modified On : Thur May 13 14:39:00 2021
// Update Count     : 0
//

#include "LinkOnce.h"

#include <algorithm>

#include "Common/PassVisitor.h"       // for PassVisitor, WithShortCircuiting

namespace CodeGen {

static bool is_cfa_linkonce( Attribute const * attr ) {
        return std::string("cfa_linkonce") == attr->name;
}

static bool is_section_attribute( Attribute const * attr ) {
        return std::string("section") == attr->name;
}

class LinkOnceVisitorCore : public WithShortCircuiting {
public:
        void previsit( Declaration * ) {
                visit_children = false;
        }

        void previsit( DeclarationWithType * decl ) {
                std::list< Attribute * > & attributes = decl->attributes;
                // See if we can find the element:
                auto found = std::find_if(attributes.begin(), attributes.end(), is_cfa_linkonce );
                if ( attributes.end() != found ) {
                        // Remove any other sections:
                        attributes.remove_if( is_section_attribute );
                        // Iterator to the cfa_linkonce attribute should still be valid.
                        Attribute * attribute = *found;
                        assert( attribute->parameters.empty() );
                        assert( !decl->mangleName.empty() );
                        // Overwrite the attribute in place.
                        const std::string section_name = ".gnu.linkonce." + decl->mangleName;
                        attribute->name = "section";
                        attribute->parameters.push_back(
                                new ConstantExpr( Constant::from_string( section_name ) )
                        );

                        // Unconditionnaly add "visibility(default)" to anything with gnu.linkonce
                        // visibility is a mess otherwise
                        attributes.push_back(new Attribute("visibility", {new ConstantExpr( Constant::from_string( "default" ) )}));

                }
                visit_children = false;
        }
};

void translateLinkOnce( std::list< Declaration *> & translationUnit ) {
        PassVisitor<LinkOnceVisitorCore> translator;
        acceptAll( translationUnit, translator );
}

}