C-Breeze C Compiler Infrastructure [ Project home page]

ternarynode.cc Go to the documentation of this file. // $Id: ternarynode.cc,v 1.3 2003/08/07 23:13:14 pnav Exp $ // ---------------------------------------------------------------------- // // C-Breeze // C Compiler Framework // // Copyright (c) 2000 University of Texas at Austin // // Samuel Z. Guyer // Daniel A. Jimenez // Calvin Lin // // Permission is hereby granted, free of charge, to any person // obtaining a copy of this software and associated documentation // files (the "Software"), to deal in the Software without // restriction, including without limitation the rights to use, copy, // modify, merge, publish, distribute, sublicense, and/or sell copies // of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be // included in all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND // NONINFRINGEMENT. IN NO EVENT SHALL THE UNIVERSITY OF TEXAS AT // AUSTIN BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF // OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. // // We acknowledge the C-to-C Translator from MIT Laboratory for // Computer Science for inspiring parts of the C-Breeze design. // // ---------------------------------------------------------------------- #include "c_breeze.h" // -------------------------------------------------------------------- // Constructors // -------------------------------------------------------------------- ternaryNode::ternaryNode(exprNode * cond, exprNode * true_br, exprNode * false_br, const Coord qmark_coord, const Coord colon_coord) : exprNode(Ternary, 0, qmark_coord), _cond(cond), _true_br(true_br), _false_br(false_br), _colon_coord(colon_coord) {} // ------------------------------------------------------------ // Operator precedence // ------------------------------------------------------------ int ternaryNode::precedence(Assoc & assoc) { assoc = Right; return 3; } // ------------------------------------------------------------ // Expression evaluator // ------------------------------------------------------------ void ternaryNode::eval() { // -- Eval the subexpressions cond()->eval(); true_br()->eval(); false_br()->eval(); // -- Test if the condition can be evaluated if ( ! cond()->value().no_val() ) if (cond()->value().Boolean()) value(true_br()->value()); else value(false_br()->value()); else value(constant()); } // ------------------------------------------------------------ // Walker // ------------------------------------------------------------ void ternaryNode::visit(Visitor * the_visitor) { the_visitor->at_ternary(this); } void ternaryNode::walk(Walker & the_walker) { Walker::Order ord = the_walker.order(); if (ord == Walker::Preorder || ord == Walker::Both) the_walker.at_ternary(this, Walker::Preorder); if (the_walker.depth() == Walker::Subtree) { // -- Visit the children if (cond()) cond()->walk(the_walker); if (true_br()) true_br()->walk(the_walker); if (false_br()) false_br()->walk(the_walker); if (type()) type()->walk(the_walker); } if (ord == Walker::Postorder || ord == Walker::Both) the_walker.at_ternary(this, Walker::Postorder); } // ------------------------------------------------------------ // Dataflow // ------------------------------------------------------------ void ternaryNode::dataflow(FlowVal * v, FlowProblem & fp) { if (fp.forward()) { fp.flow_ternary(v, this, FlowProblem::Entry); if (cond()) cond()->dataflow(v, fp); FlowVal * fv = v->clone(); if (true_br()) true_br()->dataflow(v, fp); if (false_br()) false_br()->dataflow(fv, fp); v->meet(fv); delete fv; fp.flow_ternary(v, this, FlowProblem::Exit); } else { fp.flow_ternary(v, this, FlowProblem::Exit); FlowVal * fv = v->clone(); if (true_br()) true_br()->dataflow(v, fp); if (false_br()) false_br()->dataflow(fv, fp); v->meet(fv); delete fv; if (cond()) cond()->dataflow(v, fp); fp.flow_ternary(v, this, FlowProblem::Entry); } } // ------------------------------------------------------------ // Output // ------------------------------------------------------------ void ternaryNode::output_expr(output_context & ct, Node * parent, int prec, Assoc assoc) { bool par = parens(prec, assoc); int myprec; Assoc myassoc; myprec = precedence(myassoc); if (par) ct << '('; cond()->output_expr(ct, this, myprec, Left); ct << " ? "; true_br()->output_expr(ct, this, myprec, Right); ct << " : "; false_br()->output_expr(ct, this, myprec, Right); if (par) ct << ')'; } // ------------------------------------------------------------ // Changer // ------------------------------------------------------------ Node * ternaryNode::change(Changer & the_changer, bool redispatch) { Changer::Order ord = the_changer.order(); ternaryNode * the_ternary = this; if ((ord == Changer::Preorder || ord == Changer::Both) && ! redispatch) the_ternary = (ternaryNode *) the_changer.at_ternary(the_ternary, Changer::Preorder); if (the_ternary) { if (the_ternary != this) return the_ternary->change(the_changer, true); exprNode * old_cond = the_ternary->cond(); if (old_cond) { exprNode * new_cond = (exprNode *) old_cond->change(the_changer); if (old_cond != new_cond) { //if (the_changer.delete_old()) //delete old_cond; the_ternary->cond(new_cond); } } exprNode * old_true_br = the_ternary->true_br(); if (old_true_br) { exprNode * new_true_br = (exprNode *) old_true_br->change(the_changer); if (old_true_br != new_true_br) { //if (the_changer.delete_old()) //delete old_true_br; the_ternary->true_br(new_true_br); } } exprNode * old_false_br = the_ternary->false_br(); if (old_false_br) { exprNode * new_false_br = (exprNode *) old_false_br->change(the_changer); if (old_false_br != new_false_br) { //if (the_changer.delete_old()) //delete old_false_br; the_ternary->false_br(new_false_br); } } typeNode * old_type = the_ternary->type(); if (old_type) { typeNode * new_type = (typeNode *) old_type->change(the_changer); if (old_type != new_type) { //if (the_changer.delete_old()) //delete old_type; the_ternary->type(new_type); } } } if ((ord == Changer::Postorder || ord == Changer::Both) && ! redispatch) the_ternary = (ternaryNode *) the_changer.at_ternary(the_ternary, Changer::Postorder); return the_ternary; } // ------------------------------------------------------------ // Destructor // ------------------------------------------------------------ ternaryNode::~ternaryNode() { //delete _cond; //delete _true_br; //delete _false_br; }

Generated on August 27, 2003
Back to the C-Breeze home page