source: translator/CodeGen/CodeGenerator2.cc @ c11e31c

#include <algorithm>
#include <iostream>
#include <cassert>
#include <list>

#include "SynTree/Type.h"
#include "SynTree/Declaration.h"
#include "SynTree/Statement.h"
#include "SynTree/Expression.h"
#include "SynTree/Initializer.h"

#include "utility.h"
#include "UnimplementedError.h"

#include "CodeGenerator2.h"
#include "OperatorTable.h"
#include "GenType.h"

using namespace std;

namespace CodeGen {
    int CodeGenerator2::tabsize = 4;

    CodeGenerator2::CodeGenerator2( std::ostream &os ) : cur_indent( 0 ), insideFunction( false ), before( os ), after() { }

    CodeGenerator2::CodeGenerator2( std::ostream &os, std::string init, int indent, bool infunp )
        : cur_indent( indent ), insideFunction( infunp ), before( os )
    {
        //before << std::string( init );
    }

    CodeGenerator2::CodeGenerator2( std::ostream &os, char *init, int indent, bool infunp )
        : cur_indent( indent ), insideFunction( infunp ), before( os )
    {
        //before << std::string( init );
    }

    string mangleName( DeclarationWithType *decl ) {
        if ( decl->get_mangleName() != "" ) {
            return decl->get_mangleName();
        } else {
            return decl->get_name();
        } // if
    }
  
    //*** Declarations
    void CodeGenerator2::visit( FunctionDecl *functionDecl ) {
        handleStorageClass( functionDecl );
        before << genType( functionDecl->get_functionType(), mangleName( functionDecl ) );

        // how to get this to the Functype?
        std::list< Declaration * > olds = functionDecl->get_oldDecls();
        if ( ! olds.empty() ) {
            before << " /* function has old declaration */";
        } // if

        // acceptAll( functionDecl->get_oldDecls(), *this );
        if ( functionDecl->get_statements() ) {
            functionDecl->get_statements()->accept(*this );
        } // if
    }

    void CodeGenerator2::visit( ObjectDecl *objectDecl ) {
        handleStorageClass( objectDecl );
        before << genType( objectDecl->get_type(), mangleName( objectDecl ) );
    
        if ( objectDecl->get_init() ) {
            before << " = ";
            objectDecl->get_init()->accept( *this );
        } // if
        if ( objectDecl->get_bitfieldWidth() ) {
            before << ":";
            objectDecl->get_bitfieldWidth()->accept( *this );
        } // if
    }

    void CodeGenerator2::handleAggregate( AggregateDecl *aggDecl ) {
        if ( aggDecl->get_name() != "" )
            before << aggDecl->get_name();
    
        std::list< Declaration * > &memb = aggDecl->get_members();

        if ( ! memb.empty() ) {
            before << endl << string( cur_indent, ' ' ) << "{" << endl;

            cur_indent += CodeGenerator2::tabsize; 
            for ( std::list< Declaration* >::iterator i = memb.begin(); i != memb.end();  i++) {
                before << string( cur_indent, ' ' ); 
                (*i)->accept(*this );
                before << ";" << endl;
            }

            cur_indent -= CodeGenerator2::tabsize; 

            before << string( cur_indent, ' ' ) << "}";
        } // if
    }

    void CodeGenerator2::visit( StructDecl *structDecl ) {
        before << "struct ";
        handleAggregate( structDecl );
    }

    void CodeGenerator2::visit( UnionDecl *aggregateDecl ) {
        before << "union ";
        handleAggregate( aggregateDecl );
    }
  
    void CodeGenerator2::visit( EnumDecl *aggDecl ) {
        before << "enum ";

        if ( aggDecl->get_name() != "" )
            before << aggDecl->get_name();
    
        std::list< Declaration* > &memb = aggDecl->get_members();

        if ( ! memb.empty() ) {
            before << endl << "{" << endl;

            cur_indent += CodeGenerator2::tabsize; 
            for ( std::list< Declaration* >::iterator i = memb.begin(); i != memb.end();  i++) {
                ObjectDecl *obj = dynamic_cast< ObjectDecl* >( *i );
                assert( obj );
                before << string( cur_indent, ' ' ) << mangleName( obj ); 
                if ( obj->get_init() ) {
                    before << " = ";
                    obj->get_init()->accept(*this );
                } // if
                before << "," << endl;
            }

            cur_indent -= CodeGenerator2::tabsize; 

            before << "}" << endl;
        } // if
    }
  
    void CodeGenerator2::visit( ContextDecl *aggregateDecl ) {}
  
    void CodeGenerator2::visit( TypedefDecl *typeDecl ) {
        before << "typedef ";
        before << genType( typeDecl->get_base(), typeDecl->get_name() );
    }
  
    void CodeGenerator2::visit( TypeDecl *typeDecl ) {
        // really, we should mutate this into something that isn't a TypeDecl but that requires large-scale changes,
        // still to be done
        before << "extern unsigned long " << typeDecl->get_name();
        if ( typeDecl->get_base() ) {
            before << " = sizeof( " << genType( typeDecl->get_base(), "" ) << " )";
        } // if
    }

    void CodeGenerator2::visit( SingleInit *init ) {
        init->get_value()->accept( *this );
    }

    void CodeGenerator2::visit( ListInit *init ) {
        before << "{ ";
        genCommaList( init->begin_initializers(), init->end_initializers() );
        before << " }";
    }

    void CodeGenerator2::visit( Constant *constant ) { 
        before << constant->get_value() ;
    }

    //*** Expressions
    void CodeGenerator2::visit( ApplicationExpr *applicationExpr ) {
        if ( VariableExpr *varExpr = dynamic_cast< VariableExpr* >( applicationExpr->get_function() ) ) {
            OperatorInfo opInfo;
            if ( varExpr->get_var()->get_linkage() == LinkageSpec::Intrinsic && operatorLookup( varExpr->get_var()->get_name(), opInfo ) ) {
                std::list< Expression* >::iterator arg = applicationExpr->get_args().begin();
                switch ( opInfo.type ) {
                  case OT_PREFIXASSIGN:
                  case OT_POSTFIXASSIGN:
                  case OT_INFIXASSIGN:
                    {
                        assert( arg != applicationExpr->get_args().end() );
                        if ( AddressExpr *addrExpr = dynamic_cast< AddressExpr * >( *arg ) ) {
            
                            *arg = addrExpr->get_arg();
                        } else {
                            UntypedExpr *newExpr = new UntypedExpr( new NameExpr( "*?" ) );
                            newExpr->get_args().push_back( *arg );
                            *arg = newExpr;
                        } // if
                        break;
                    }
          
                  default:
                    // do nothing
                    ;
                }
        
                switch ( opInfo.type ) {
                  case OT_INDEX:
                    assert( applicationExpr->get_args().size() == 2 );
                    (*arg++)->accept( *this );
                    before << "[";
                    (*arg)->accept( *this );
                    before << "]";
                    break;
          
                  case OT_CALL:
                    // there are no intrinsic definitions of the function call operator
                    assert( false );
                    break;
          
                  case OT_PREFIX:
                  case OT_PREFIXASSIGN:
                    assert( applicationExpr->get_args().size() == 1 );
                    before << "(";
                    before << opInfo.symbol;
                    (*arg)->accept( *this );
                    before << ")";
                    break;
          
                  case OT_POSTFIX:
                  case OT_POSTFIXASSIGN:
                    assert( applicationExpr->get_args().size() == 1 );
                    (*arg)->accept( *this );
                    before << opInfo.symbol;
                    break;

                  case OT_INFIX:
                  case OT_INFIXASSIGN:
                    assert( applicationExpr->get_args().size() == 2 );
                    before << "(";
                    (*arg++)->accept( *this );
                    before << opInfo.symbol;
                    (*arg)->accept( *this );
                    before << ")";
                    break;
          
                  case OT_CONSTANT:
                    // there are no intrinsic definitions of 0 or 1 as functions
                    assert( false );
                }
            } else {
                varExpr->accept( *this );
                before << "(";
                genCommaList( applicationExpr->get_args().begin(), applicationExpr->get_args().end() );
                before << ")";
            } // if
        } else {
            applicationExpr->get_function()->accept( *this );
            before << "(";
            genCommaList( applicationExpr->get_args().begin(), applicationExpr->get_args().end() );
            before << ")";
        } // if
    }
  
    void CodeGenerator2::visit( UntypedExpr *untypedExpr ) {
        if ( NameExpr *nameExpr = dynamic_cast< NameExpr* >( untypedExpr->get_function() ) ) {
            OperatorInfo opInfo;
            if ( operatorLookup( nameExpr->get_name(), opInfo ) ) {
                std::list< Expression* >::iterator arg = untypedExpr->get_args().begin();
                switch ( opInfo.type ) {
                  case OT_INDEX:
                    assert( untypedExpr->get_args().size() == 2 );
                    (*arg++)->accept( *this );
                    before << "[";
                    (*arg)->accept( *this );
                    before << "]";
                    break;
          
                  case OT_CALL:
                    assert( false );
                    break;
          
                  case OT_PREFIX:
                  case OT_PREFIXASSIGN:
                    assert( untypedExpr->get_args().size() == 1 );
                    before << "(";
                    before << opInfo.symbol;
                    (*arg)->accept( *this );
                    before << ")";
                    break;
          
                  case OT_POSTFIX:
                  case OT_POSTFIXASSIGN:
                    assert( untypedExpr->get_args().size() == 1 );
                    (*arg)->accept( *this );
                    before << opInfo.symbol;
                    break;
  
                  case OT_INFIX:
                  case OT_INFIXASSIGN:
                    assert( untypedExpr->get_args().size() == 2 );
                    before << "(";
                    (*arg++)->accept( *this );
                    before << opInfo.symbol;
                    (*arg)->accept( *this );
                    before << ")";
                    break;
          
                  case OT_CONSTANT:
                    // there are no intrinsic definitions of 0 or 1 as functions
                    assert( false );
                }
            } else {
                nameExpr->accept( *this );
                before << "(";
                genCommaList( untypedExpr->get_args().begin(), untypedExpr->get_args().end() );
                before << ")";
            } // if
        } else {
            untypedExpr->get_function()->accept( *this );
            before << "(";
            genCommaList( untypedExpr->get_args().begin(), untypedExpr->get_args().end() );
            before << ")";
        } // if
    }
  
    void CodeGenerator2::visit( NameExpr *nameExpr ) {
        OperatorInfo opInfo;
        if ( operatorLookup( nameExpr->get_name(), opInfo ) ) {
            assert( opInfo.type == OT_CONSTANT );
            before << opInfo.symbol;
        } else {
            before << nameExpr->get_name();
        } // if
    }
  
    void CodeGenerator2::visit( AddressExpr *addressExpr ) {
        before << "(&";
        // this hack makes sure that we don't convert "constant_zero" to "0" if we're taking its address
        if ( VariableExpr *variableExpr = dynamic_cast< VariableExpr* >( addressExpr->get_arg() ) ) {
            before << mangleName( variableExpr->get_var() );
        } else {
            addressExpr->get_arg()->accept( *this );
        } // if
        before << ")";
    }

    void CodeGenerator2::visit( CastExpr *castExpr ) {
        before << "((";
        if ( castExpr->get_results().empty() ) {
            before << "void" ;
        } else {
            before << genType( castExpr->get_results().front(), "" );
        } // if
        before << ")";
        castExpr->get_arg()->accept( *this );
        before << ")";
    }
  
    void CodeGenerator2::visit( UntypedMemberExpr *memberExpr ) {
        assert( false );
    }
  
    void CodeGenerator2::visit( MemberExpr *memberExpr ) {
        memberExpr->get_aggregate()->accept( *this );
        before << "." << mangleName( memberExpr->get_member() );
    }
  
    void CodeGenerator2::visit( VariableExpr *variableExpr ) {
        OperatorInfo opInfo;
        if ( variableExpr->get_var()->get_linkage() == LinkageSpec::Intrinsic && operatorLookup( variableExpr->get_var()->get_name(), opInfo ) && opInfo.type == OT_CONSTANT ) {
            before << opInfo.symbol;
        } else {
            before << mangleName( variableExpr->get_var() );
        } // if
    }
  
    void CodeGenerator2::visit( ConstantExpr *constantExpr ) {
        assert( constantExpr->get_constant() );
        constantExpr->get_constant()->accept( *this );
    }
  
    void CodeGenerator2::visit( SizeofExpr *sizeofExpr ) {
        before << "sizeof(";
        if ( sizeofExpr->get_isType() ) {
            before << genType( sizeofExpr->get_type(), "" );
        } else {
            sizeofExpr->get_expr()->accept( *this );
        } // if
        before << ")";
    }
  
    void CodeGenerator2::visit( LogicalExpr *logicalExpr ) {
        before << "(";
        logicalExpr->get_arg1()->accept( *this );
        if ( logicalExpr->get_isAnd() ) {
            before << " && ";
        } else {
            before << " || ";
        } // if
        logicalExpr->get_arg2()->accept( *this );
        before << ")";
    }
  
    void CodeGenerator2::visit( ConditionalExpr *conditionalExpr ) {
        before << "(";
        conditionalExpr->get_arg1()->accept( *this );
        before << " ? ";
        conditionalExpr->get_arg2()->accept( *this );
        before << " : ";
        conditionalExpr->get_arg3()->accept( *this );
        before << ")";
    }
  
    void CodeGenerator2::visit( CommaExpr *commaExpr ) {
        before << "(";
        commaExpr->get_arg1()->accept( *this );
        before << " , ";
        commaExpr->get_arg2()->accept( *this );
        before << ")";
    }
  
    void CodeGenerator2::visit( TupleExpr *tupleExpr ) {}
  
    void CodeGenerator2::visit( TypeExpr *typeExpr ) {}
  
  
    //*** Statements
    void CodeGenerator2::visit( CompoundStmt *compoundStmt ) {
        std::list<Statement*> ks = compoundStmt->get_kids();

        before << endl << string( cur_indent, ' ' ) << "{" << endl;

        cur_indent += CodeGenerator2::tabsize; 

        for ( std::list<Statement *>::iterator i = ks.begin(); i != ks.end();  i++) {
            before << string( cur_indent, ' ' ) << printLabels( (*i)->get_labels() )  ;
            (*i)->accept(*this );
            shift_left();
            before << endl;
        }
        cur_indent -= CodeGenerator2::tabsize; 

        before << string( cur_indent, ' ' ) << "}" << endl;
    }

    void CodeGenerator2::visit( ExprStmt *exprStmt ) {
        if ( exprStmt != 0 ) {
            exprStmt->get_expr()->accept( *this );
            shift_left();
            before << ";" ;
        } // if
    }

    void CodeGenerator2::visit( IfStmt *ifStmt ) {
        before << "if (";
        ifStmt->get_condition()->accept(*this );
        after += ")\n";
        shift_left(); 

        cur_indent += CodeGenerator2::tabsize;
        before << string( cur_indent, ' ' );
        ifStmt->get_thenPart()->accept(*this );
        cur_indent -= CodeGenerator2::tabsize; 
        shift_left(); before << endl;

        if ( ifStmt->get_elsePart() != 0) {
            before << string( cur_indent, ' ' ) << " else " << endl ;

            cur_indent += CodeGenerator2::tabsize; 
            ifStmt->get_elsePart()->accept(*this );
            cur_indent -= CodeGenerator2::tabsize; 
        } // if
    }

    void CodeGenerator2::visit( SwitchStmt *switchStmt ) {
        //before << /* "\r" << */ string( cur_indent, ' ' ) << CodeGenerator2::printLabels( switchStmt->get_labels() ) 
        before << "switch (" ;
        switchStmt->get_condition()->accept(*this );
        after += ")\n";
        shift_left();

        before << string( cur_indent, ' ' ) << "{" << std::endl;
        cur_indent += CodeGenerator2::tabsize;

        std::list< Statement * > stmts = switchStmt->get_branches();
        bool lastBreak = false; 

        // horrible, horrible hack
        if ( dynamic_cast<BranchStmt *>( stmts.back() ) != 0 ) {
            lastBreak = true;
            stmts.pop_back();
        } // if
        acceptAll( stmts, *this );
        if ( lastBreak ) {
            Statement *st = switchStmt->get_branches().back();
            before << CodeGenerator2::printLabels( st->get_labels());
            st->accept( *this );
        } // if
      
        cur_indent -= CodeGenerator2::tabsize; 

        before << /* "\r" << */ string( cur_indent, ' ' ) << "}" << endl ;
    }

    void CodeGenerator2::visit( CaseStmt *caseStmt ) {
        before << string( cur_indent, ' ' );
        if ( caseStmt->isDefault()) 
            before << "default "  ;
        else {
            before << "case "  ;
            caseStmt->get_condition()->accept(*this );
        } // if
        after += ":\n";
        shift_left();

        std::list<Statement *> sts = caseStmt->get_statements();

        cur_indent += CodeGenerator2::tabsize;
        for ( std::list<Statement *>::iterator i = sts.begin(); i != sts.end();  i++) {
            before << /* "\r" << */ string( cur_indent, ' ' ) << printLabels( (*i)->get_labels() )  ;
            (*i)->accept(*this );
            shift_left();
            before << ";" << endl;
        }
        cur_indent -= CodeGenerator2::tabsize;
    }

    void CodeGenerator2::visit( BranchStmt *branchStmt ) {
        switch ( branchStmt->get_type()) {
          case BranchStmt::Goto:
            if ( ! branchStmt->get_target().empty() )
                before << "goto " << branchStmt->get_target();
            else { 
                if ( branchStmt->get_computedTarget() != 0 ) {
                    before << "goto *";
                    branchStmt->get_computedTarget()->accept( *this );
                } // if
            } // if
            break;
          case BranchStmt::Break:
            before << "break";
            break;
          case BranchStmt::Continue:
            before << "continue";
            break;
        }
        before << ";";
    }


    void CodeGenerator2::visit( ReturnStmt *returnStmt ) {
        before << "return ";

        // xxx -- check for null expression;
        if ( returnStmt->get_expr() ) {
            returnStmt->get_expr()->accept( *this );
        } // if
        after += ";";
    }

    void CodeGenerator2::visit( WhileStmt *whileStmt ) {
        if ( whileStmt->get_isDoWhile() )
            before << "do" ;
        else {
            before << "while(" ;
            whileStmt->get_condition()->accept(*this );
            after += ")";
        } // if
        after += "{\n";
        shift_left();

        whileStmt->get_body()->accept( *this );

        before << /* "\r" << */ string( cur_indent, ' ' ) << "}" ;

        if ( whileStmt->get_isDoWhile() ) {
            before << " while(" ;
            whileStmt->get_condition()->accept(*this );
            after += ");";
        } // if

        after += "\n";
    }

    void CodeGenerator2::visit( ForStmt *forStmt ) {
        before << "for (";

        if ( forStmt->get_initialization() != 0 )
            forStmt->get_initialization()->accept( *this );
        else
            before << ";";
        shift_left();

        if ( forStmt->get_condition() != 0 )
            forStmt->get_condition()->accept( *this );
        shift_left(); before << ";";

        if ( forStmt->get_increment() != 0 )
            forStmt->get_increment()->accept( *this );
        shift_left(); before << ")" << endl;

        if ( forStmt->get_body() != 0 ) {
            cur_indent += CodeGenerator2::tabsize; 
            before << string( cur_indent, ' ' ) << CodeGenerator2::printLabels( forStmt->get_body()->get_labels() );
            forStmt->get_body()->accept( *this );
            cur_indent -= CodeGenerator2::tabsize; 
        } // if
    }

    void CodeGenerator2::visit( NullStmt *nullStmt ) {
        //before << /* "\r" << */ string( cur_indent, ' ' ) << CodeGenerator2::printLabels( nullStmt->get_labels() );
        before << "/* null statement */ ;";
    }

    void CodeGenerator2::visit( DeclStmt *declStmt ) {
        declStmt->get_decl()->accept( *this );
    
        if ( doSemicolon( declStmt->get_decl() ) ) {
            after += ";";
        } // if
        shift_left();
    }

    std::string CodeGenerator2::printLabels( std::list< Label > &l ) {
        std::string str( "" );
        l.unique();

        for ( std::list< Label >::iterator i = l.begin(); i != l.end(); i++ )
            str += *i + ": ";

        return str;
    }

    void CodeGenerator2::shift_left() {
        before << after;
        after = "";
    }

    void CodeGenerator2::handleStorageClass( Declaration *decl ) {
        switch ( decl->get_storageClass() ) {
          case Declaration::NoStorageClass:
            break;
          case Declaration::Extern:
            before << "extern ";
            break;
          case Declaration::Static:
            before << "static ";
            break;
          case Declaration::Auto:
            // silently drop storage class
            break;
          case Declaration::Register:
            before << "register ";
            break;
          case Declaration::Inline:
            before << "inline ";
            break;
          case Declaration::Fortran:
            before << "fortran ";
            break;
        }
    }
} // namespace CodeGen