bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/planning/items/GenericPrePlanItem.java

   1 package org.simantics.scl.compiler.elaboration.chr.planning.items;
   2
   3 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
   4 import org.simantics.scl.compiler.elaboration.chr.CHRLiteral;
   5 import org.simantics.scl.compiler.elaboration.chr.CHRRelation;
   6 import org.simantics.scl.compiler.elaboration.chr.plan.CheckOp;
   7 import org.simantics.scl.compiler.elaboration.chr.plan.IterateConstraintOp;
   8 import org.simantics.scl.compiler.elaboration.chr.plan.IterateRelationOp;
   9 import org.simantics.scl.compiler.elaboration.chr.planning.PrePlanItem;
  10 import org.simantics.scl.compiler.elaboration.chr.planning.QueryPlanningContext;
  11 import org.simantics.scl.compiler.elaboration.chr.relations.CHRConstraint;
  12 import org.simantics.scl.compiler.elaboration.chr.relations.ExternalCHRRelation;
  13 import org.simantics.scl.compiler.elaboration.expressions.EApply;
  14 import org.simantics.scl.compiler.elaboration.expressions.EConstant;
  15 import org.simantics.scl.compiler.elaboration.expressions.EVariable;
  16 import org.simantics.scl.compiler.elaboration.expressions.Expression;
  17 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  18 import org.simantics.scl.compiler.elaboration.java.Builtins;
  19 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
  20
  21 import gnu.trove.set.hash.THashSet;
  22 import gnu.trove.set.hash.TIntHashSet;
  23
  24 public class GenericPrePlanItem extends PrePlanItem {
  25     public CHRLiteral literal;
  26     public CHRRelation relation;
  27     public Expression[] expressions;
  28     public TIntHashSet[] variableSets;
  29     TIntHashSet allVars;
  30
  31     public GenericPrePlanItem(CHRLiteral literal, CHRRelation relation, Expression[] expressions,
  32             TIntHashSet[] variableSets, int secondaryPriority) {
  33         super(secondaryPriority);
  34         this.literal = literal;
  35         this.relation = relation;
  36         this.expressions = expressions;
  37         this.variableSets = variableSets;
  38         allVars = new TIntHashSet();
  39         for(TIntHashSet variableSet : variableSets)
  40             allVars.addAll(variableSet);
  41         updatePrimaryPriority();
  42     }
  43
  44     private void updatePrimaryPriority() {
  45         int boundCount = 0;
  46         int boundMask = 0;
  47         for(int i=0;i<variableSets.length;++i)
  48             if(variableSets[i].isEmpty()) {
  49                 ++boundCount;
  50                 boundMask |= 1 << i;
  51             }
  52         if(boundCount == variableSets.length)
  53             primaryPriority = 0;
  54         else {
  55             if(relation instanceof ExternalCHRRelation) {
  56                 SCLRelation sclRelation = ((ExternalCHRRelation)relation).relation;
  57                 double selectivity = sclRelation.getSelectivity(boundMask);
  58                 if(selectivity == Double.POSITIVE_INFINITY)
  59                     primaryPriority = Double.POSITIVE_INFINITY;
  60                 else if(selectivity < 1.0)
  61                     primaryPriority = 0.0;
  62                 else if(selectivity == 1.0)
  63                     primaryPriority = 1.0;
  64                 else
  65                     primaryPriority = 3.0 - ((double)boundCount) / variableSets.length;
  66             }
  67             else
  68                 primaryPriority = 3.0 - ((double)boundCount) / variableSets.length;
  69         }
  70     }
  71
  72     @Override
  73     public void initializeListeners(QueryPlanningContext context) {
  74         context.listen(allVars, this);
  75     }
  76
  77     @Override
  78     public void variableSolved(QueryPlanningContext context, int variableId) {
  79         for(TIntHashSet variableSet : variableSets)
  80             variableSet.remove(variableId);
  81         allVars.remove(variableId);
  82         updatePrimaryPriority();
  83         context.priorityQueue.adjust(this);
  84     }
  85
  86     @Override
  87     public void generate(QueryPlanningContext context) {
  88         int boundMask = 0;
  89         Expression[] boundExpressions = new Expression[expressions.length];
  90         Variable[] freeVariables = new Variable[expressions.length];
  91         int freeVariableCount = 0;
  92         for(int i=0;i<expressions.length;++i)
  93             if(variableSets[i].isEmpty()) {
  94                 boundExpressions[i] = expressions[i];
  95                 boundMask |= 1 << i;
  96             }
  97             else {
  98                 freeVariables[i] = ((EVariable)expressions[i]).getVariable();
  99                 ++freeVariableCount;
 100             }
 101         if(relation instanceof CHRConstraint)
 102             context.addPlanOp(new IterateConstraintOp(location, (CHRConstraint)relation, freeVariables, boundExpressions, boundMask,
 103                     killAfterMatch(), literal.passive));
 104         else if(relation instanceof ExternalCHRRelation)
 105             context.addPlanOp(new IterateRelationOp(location, ((ExternalCHRRelation)relation).relation,
 106                     freeVariables, boundExpressions, literal.typeConstraintEvidenceParameters, boundMask));
 107         else
 108             throw new InternalCompilerError();
 109         if(freeVariableCount > 1) {
 110             THashSet<Variable> usedVariables = new THashSet<Variable>(freeVariableCount);
 111             for(int i=0;i<freeVariables.length;++i) {
 112                 Variable variable = freeVariables[i];
 113                 if(variable == null)
 114                     continue;
 115                 if(!usedVariables.add(variable)) {
 116                     Variable auxiliary = new Variable(variable.getName(), variable.getType());
 117                     freeVariables[i] = auxiliary;
 118                     context.addPlanOp(new CheckOp(location, new EApply(location, new EConstant(Builtins.EQUALS, variable.getType()), new EVariable(auxiliary), new EVariable(variable))));
 119                 }
 120             }
 121         }
 122         context.bind(allVars);
 123     }
 124
 125     private boolean killAfterMatch() {
 126         return literal.killAfterMatch && relation instanceof CHRConstraint;
 127     }
 128 }