source: src/Parser/StatementNode.cc @ 436bbe5

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// StatementNode.cc --
//
// Author           : Rodolfo G. Esteves
// Created On       : Sat May 16 14:59:41 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Wed Feb  2 09:45:28 2022
// Update Count     : 415
//

#include <cassert>                 // for assert, strict_dynamic_cast, assertf
#include <list>                    // for list
#include <memory>                  // for unique_ptr
#include <string>                  // for string

#include "Common/SemanticError.h"  // for SemanticError
#include "Common/utility.h"        // for maybeMoveBuild, maybeBuild
#include "ParseNode.h"             // for StatementNode, ExpressionNode, bui...
#include "SynTree/Expression.h"    // for Expression, ConstantExpr
#include "SynTree/Label.h"         // for Label, noLabels
#include "SynTree/Declaration.h"
#include "SynTree/Statement.h"     // for Statement, BranchStmt, CaseStmt
#include "parserutility.h"         // for notZeroExpr

class Declaration;

using namespace std;


StatementNode::StatementNode( DeclarationNode * decl ) {
        assert( decl );
        DeclarationNode * agg = decl->extractAggregate();
        if ( agg ) {
                StatementNode * nextStmt = new StatementNode( new DeclStmt( maybeBuild< Declaration >( decl ) ) );
                set_next( nextStmt );
                if ( decl->get_next() ) {
                        get_next()->set_next( new StatementNode( dynamic_cast< DeclarationNode * >(decl->get_next()) ) );
                        decl->set_next( 0 );
                } // if
        } else {
                if ( decl->get_next() ) {
                        set_next( new StatementNode( dynamic_cast< DeclarationNode * >( decl->get_next() ) ) );
                        decl->set_next( 0 );
                } // if
                agg = decl;
        } // if
        stmt.reset( new DeclStmt( maybeMoveBuild< Declaration >(agg) ) );
} // StatementNode::StatementNode

StatementNode * StatementNode::append_last_case( StatementNode * stmt ) {
        StatementNode * prev = this;
        // find end of list and maintain previous pointer
        for ( StatementNode * curr = prev; curr != nullptr; curr = (StatementNode *)curr->get_next() ) {
                StatementNode * node = strict_dynamic_cast< StatementNode * >(curr);
                assert( dynamic_cast< CaseStmt * >(node->stmt.get()) );
                prev = curr;
        } // for
        // convert from StatementNode list to Statement list
        StatementNode * node = dynamic_cast< StatementNode * >(prev);
        list< Statement * > stmts;
        buildMoveList( stmt, stmts );
        // splice any new Statements to end of current Statements
        CaseStmt * caseStmt = dynamic_cast< CaseStmt * >(node->stmt.get());
        caseStmt->get_statements().splice( caseStmt->get_statements().end(), stmts );
        return this;
} // StatementNode::append_last_case

Statement * build_expr( ExpressionNode * ctl ) {
        Expression * e = maybeMoveBuild< Expression >( ctl );

        if ( e ) return new ExprStmt( e );
        else return new NullStmt();
} // build_expr

Expression * build_if_control( CondCtl * ctl, list< Statement * > & init ) {
        if ( ctl->init != 0 ) {
                buildMoveList( ctl->init, init );
        } // if

        Expression * cond = nullptr;
        if ( ctl->condition ) {
                // compare the provided condition against 0
                cond = notZeroExpr( maybeMoveBuild< Expression >(ctl->condition) );
        } else {
                for ( Statement * stmt : init ) {
                        // build the && of all of the declared variables compared against 0
                        DeclStmt * declStmt = strict_dynamic_cast< DeclStmt * >( stmt );
                        DeclarationWithType * dwt = strict_dynamic_cast< DeclarationWithType * >( declStmt->decl );
                        Expression * nze = notZeroExpr( new VariableExpr( dwt ) );
                        cond = cond ? new LogicalExpr( cond, nze, true ) : nze;
                }
        }
        delete ctl;
        return cond;
} // build_if_control

Statement * build_if( CondCtl * ctl, StatementNode * then, StatementNode * else_ ) {
        list< Statement * > astinit;                                            // maybe empty
        Expression * astcond = build_if_control( ctl, astinit ); // ctl deleted, cond/init set

        Statement * astthen, * astelse = nullptr;
        list< Statement * > aststmt;
        buildMoveList< Statement, StatementNode >( then, aststmt );
        assert( aststmt.size() == 1 );
        astthen = aststmt.front();

        if ( else_ ) {
                list< Statement * > aststmt;
                buildMoveList< Statement, StatementNode >( else_, aststmt );
                assert( aststmt.size() == 1 );
                astelse = aststmt.front();
        } // if

        return new IfStmt( astcond, astthen, astelse, astinit );
} // build_if

Statement * build_switch( bool isSwitch, ExpressionNode * ctl, StatementNode * stmt ) {
        list< Statement * > aststmt;
        buildMoveList< Statement, StatementNode >( stmt, aststmt );
        if ( ! isSwitch ) {                                                                     // choose statement
                for ( Statement * stmt : aststmt ) {
                        CaseStmt * caseStmt = strict_dynamic_cast< CaseStmt * >( stmt );
                        if ( ! caseStmt->stmts.empty() ) {                      // code after "case" => end of case list
                                CompoundStmt * block = strict_dynamic_cast< CompoundStmt * >( caseStmt->stmts.front() );
                                block->kids.push_back( new BranchStmt( "", BranchStmt::Break ) );
                        } // if
                } // for
        } // if
        // aststmt.size() == 0 for switch (...) {}, i.e., no declaration or statements
        return new SwitchStmt( maybeMoveBuild< Expression >(ctl), aststmt );
} // build_switch

Statement * build_case( ExpressionNode * ctl ) {
        return new CaseStmt( maybeMoveBuild< Expression >(ctl), list< Statement * >{} );
} // build_case

Statement * build_default() {
        return new CaseStmt( nullptr, list< Statement * >{}, true );
} // build_default

Statement * build_while( CondCtl * ctl, StatementNode * stmt, StatementNode * else_ ) {
        list< Statement * > astinit;                                            // maybe empty
        Expression * astcond = build_if_control( ctl, astinit ); // ctl deleted, cond/init set

        list< Statement * > aststmt;                                            // loop body, compound created if empty
        buildMoveList< Statement, StatementNode >( stmt, aststmt );
        assert( aststmt.size() == 1 );

        list< Statement * > astelse;                                            // else clause, maybe empty
        buildMoveList< Statement, StatementNode >( else_, astelse );

        return new WhileDoStmt( astcond, aststmt.front(), astelse.front(), astinit, false );
} // build_while

Statement * build_do_while( ExpressionNode * ctl, StatementNode * stmt, StatementNode * else_ ) {
        // do-while cannot have declarations in the contitional, so always empty
        list< Statement * > astinit;

        list< Statement * > aststmt;                                            // loop body, compound created if empty
        buildMoveList< Statement, StatementNode >( stmt, aststmt );
        assert( aststmt.size() == 1 );                                          // compound created if empty

        list< Statement * > astelse;                                            // else clause, maybe empty
        buildMoveList< Statement, StatementNode >( else_, astelse );

        return new WhileDoStmt( notZeroExpr( maybeMoveBuild< Expression >(ctl) ), aststmt.front(), astelse.front(), astinit, true );
} // build_do_while

Statement * build_for( ForCtrl * forctl, StatementNode * stmt, StatementNode * else_ ) {
        list< Statement * > astinit;                                            // maybe empty
        buildMoveList( forctl->init, astinit );

        Expression * astcond = nullptr;                                         // maybe empty
        astcond = notZeroExpr( maybeMoveBuild< Expression >(forctl->condition) );

        Expression * astincr = nullptr;                                         // maybe empty
        astincr = maybeMoveBuild< Expression >(forctl->change);
        delete forctl;

        list< Statement * > aststmt;                                            // loop body, compound created if empty
        buildMoveList< Statement, StatementNode >( stmt, aststmt );
        assert( aststmt.size() == 1 );

        list< Statement * > astelse;                                            // else clause, maybe empty
        buildMoveList< Statement, StatementNode >( else_, astelse );

        return new ForStmt( astinit, astcond, astincr, aststmt.front(), astelse.front() );
} // build_for

Statement * build_branch( BranchStmt::Type kind ) {
        Statement * ret = new BranchStmt( "", kind );
        return ret;
} // build_branch

Statement * build_branch( string * identifier, BranchStmt::Type kind ) {
        Statement * ret = new BranchStmt( * identifier, kind );
        delete identifier;                                                                      // allocated by lexer
        return ret;
} // build_branch

Statement * build_computedgoto( ExpressionNode * ctl ) {
        return new BranchStmt( maybeMoveBuild< Expression >(ctl), BranchStmt::Goto );
} // build_computedgoto

Statement * build_return( ExpressionNode * ctl ) {
        list< Expression * > exps;
        buildMoveList( ctl, exps );
        return new ReturnStmt( exps.size() > 0 ? exps.back() : nullptr );
} // build_return

Statement * build_throw( ExpressionNode * ctl ) {
        list< Expression * > exps;
        buildMoveList( ctl, exps );
        assertf( exps.size() < 2, "CFA internal error: leaking memory" );
        return new ThrowStmt( ThrowStmt::Terminate, !exps.empty() ? exps.back() : nullptr );
} // build_throw

Statement * build_resume( ExpressionNode * ctl ) {
        list< Expression * > exps;
        buildMoveList( ctl, exps );
        assertf( exps.size() < 2, "CFA internal error: leaking memory" );
        return new ThrowStmt( ThrowStmt::Resume, !exps.empty() ? exps.back() : nullptr );
} // build_resume

Statement * build_resume_at( ExpressionNode * ctl, ExpressionNode * target ) {
        (void)ctl;
        (void)target;
        assertf( false, "resume at (non-local throw) is not yet supported," );
} // build_resume_at

Statement * build_try( StatementNode * try_, StatementNode * catch_, StatementNode * finally_ ) {
        list< CatchStmt * > aststmt;
        buildMoveList< CatchStmt, StatementNode >( catch_, aststmt );
        CompoundStmt * tryBlock = strict_dynamic_cast< CompoundStmt * >(maybeMoveBuild< Statement >(try_));
        FinallyStmt * finallyBlock = dynamic_cast< FinallyStmt * >(maybeMoveBuild< Statement >(finally_) );
        return new TryStmt( tryBlock, aststmt, finallyBlock );
} // build_try

Statement * build_catch( CatchStmt::Kind kind, DeclarationNode * decl, ExpressionNode * cond, StatementNode * body ) {
        list< Statement * > aststmt;
        buildMoveList< Statement, StatementNode >( body, aststmt );
        assert( aststmt.size() == 1 );
        return new CatchStmt( kind, maybeMoveBuild< Declaration >(decl), maybeMoveBuild< Expression >(cond), aststmt.front() );
} // build_catch

Statement * build_finally( StatementNode * stmt ) {
        list< Statement * > aststmt;
        buildMoveList< Statement, StatementNode >( stmt, aststmt );
        assert( aststmt.size() == 1 );
        return new FinallyStmt( dynamic_cast< CompoundStmt * >( aststmt.front() ) );
} // build_finally

SuspendStmt * build_suspend( StatementNode * then, SuspendStmt::Type type ) {
        auto node = new SuspendStmt();

        node->type = type;

        list< Statement * > stmts;
        buildMoveList< Statement, StatementNode >( then, stmts );
        if(!stmts.empty()) {
                assert( stmts.size() == 1 );
                node->then = dynamic_cast< CompoundStmt * >( stmts.front() );
        }

        return node;
}

WaitForStmt * build_waitfor( ExpressionNode * targetExpr, StatementNode * stmt, ExpressionNode * when ) {
        auto node = new WaitForStmt();

        WaitForStmt::Target target;
        target.function = maybeBuild<Expression>( targetExpr );

        ExpressionNode * next = dynamic_cast<ExpressionNode *>( targetExpr->get_next() );
        targetExpr->set_next( nullptr );
        buildMoveList< Expression >( next, target.arguments );

        delete targetExpr;

        node->clauses.push_back( WaitForStmt::Clause{
                target,
                maybeMoveBuild<Statement >( stmt ),
                notZeroExpr( maybeMoveBuild<Expression>( when ) )
        });

        return node;
} // build_waitfor

WaitForStmt * build_waitfor( ExpressionNode * targetExpr, StatementNode * stmt, ExpressionNode * when, WaitForStmt * node ) {
        WaitForStmt::Target target;
        target.function = maybeBuild<Expression>( targetExpr );

        ExpressionNode * next = dynamic_cast<ExpressionNode *>( targetExpr->get_next() );
        targetExpr->set_next( nullptr );
        buildMoveList< Expression >( next, target.arguments );

        delete targetExpr;

        node->clauses.insert( node->clauses.begin(), WaitForStmt::Clause{
                std::move( target ),
                maybeMoveBuild<Statement >( stmt ),
                notZeroExpr( maybeMoveBuild<Expression>( when ) )
        });

        return node;
} // build_waitfor

WaitForStmt * build_waitfor_timeout( ExpressionNode * timeout, StatementNode * stmt, ExpressionNode * when ) {
        auto node = new WaitForStmt();

        if( timeout ) {
                node->timeout.time      = maybeMoveBuild<Expression>( timeout );
                node->timeout.statement = maybeMoveBuild<Statement >( stmt    );
                node->timeout.condition = notZeroExpr( maybeMoveBuild<Expression>( when ) );
        } else {
                node->orelse.statement  = maybeMoveBuild<Statement >( stmt );
                node->orelse.condition  = notZeroExpr( maybeMoveBuild<Expression>( when ) );
        } // if

        return node;
} // build_waitfor_timeout

WaitForStmt * build_waitfor_timeout( ExpressionNode * timeout, StatementNode * stmt, ExpressionNode * when,  StatementNode * else_, ExpressionNode * else_when ) {
        auto node = new WaitForStmt();

        node->timeout.time      = maybeMoveBuild<Expression>( timeout );
        node->timeout.statement = maybeMoveBuild<Statement >( stmt    );
        node->timeout.condition = notZeroExpr( maybeMoveBuild<Expression>( when ) );

        node->orelse.statement  = maybeMoveBuild<Statement >( else_ );
        node->orelse.condition  = notZeroExpr( maybeMoveBuild<Expression>( else_when ) );

        return node;
} // build_waitfor_timeout

Statement * build_with( ExpressionNode * exprs, StatementNode * stmt ) {
        list< Expression * > e;
        buildMoveList( exprs, e );
        Statement * s = maybeMoveBuild<Statement>( stmt );
        return new DeclStmt( new WithStmt( e, s ) );
} // build_with

Statement * build_compound( StatementNode * first ) {
        CompoundStmt * cs = new CompoundStmt();
        buildMoveList( first, cs->get_kids() );
        return cs;
} // build_compound

// A single statement in a control structure is always converted to a compound statement so subsequent generated code
// can be placed within this compound statement. Otherwise, code generation has to constantly check for a single
// statement and wrap it into a compound statement to insert additional code. Hence, all control structures have a
// conical form for code generation.
StatementNode * maybe_build_compound( StatementNode * first ) {
        // Optimization: if the control-structure statement is a compound statement, do not wrap it.
        // e.g., if (...) {...} do not wrap the existing compound statement.
        if ( ! dynamic_cast<CompoundStmt *>( first->stmt.get() ) ) { // unique_ptr
                CompoundStmt * cs = new CompoundStmt();
                buildMoveList( first, cs->get_kids() );
                return new StatementNode( cs );
        } // if
        return first;
} // maybe_build_compound

Statement * build_asm( bool voltile, Expression * instruction, ExpressionNode * output, ExpressionNode * input, ExpressionNode * clobber, LabelNode * gotolabels ) {
        list< Expression * > out, in;
        list< ConstantExpr * > clob;

        buildMoveList( output, out );
        buildMoveList( input, in );
        buildMoveList( clobber, clob );
        return new AsmStmt( voltile, instruction, out, in, clob, gotolabels ? gotolabels->labels : noLabels );
} // build_asm

Statement * build_directive( string * directive ) {
        return new DirectiveStmt( *directive );
} // build_directive

Statement * build_mutex( ExpressionNode * exprs, StatementNode * stmt ) {
        list< Expression * > expList;
        buildMoveList( exprs, expList );
        Statement * body = maybeMoveBuild<Statement>( stmt );
        return new MutexStmt( body, expList );
} // build_mutex

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //