bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/relations/LocalRelation.java

   1 package org.simantics.scl.compiler.elaboration.relations;
   2
   3 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.*;
   4
   5 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
   6 import org.simantics.scl.compiler.common.names.Name;
   7 import org.simantics.scl.compiler.elaboration.expressions.ERuleset;
   8 import org.simantics.scl.compiler.elaboration.expressions.EVariable;
   9 import org.simantics.scl.compiler.elaboration.expressions.Expressions;
  10 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  11 import org.simantics.scl.compiler.elaboration.query.compilation.QueryCompilationContext;
  12 import org.simantics.scl.compiler.types.TVar;
  13 import org.simantics.scl.compiler.types.Type;
  14 import org.simantics.scl.compiler.types.Types;
  15 import org.simantics.scl.compiler.types.kinds.Kinds;
  16
  17 public class LocalRelation extends AbstractRelation {
  18     String name;
  19     Type[] parameterTypes;
  20     public Variable table;
  21
  22     public LocalRelation(String name, int arity) {
  23         this.name = name;
  24         this.parameterTypes = new Type[arity];
  25         for(int i=0;i<arity;++i)
  26             parameterTypes[i] = Types.metaVar(Kinds.STAR);
  27         createTable();
  28     }
  29
  30     public LocalRelation(String name, Type[] parameterTypes) {
  31         this.name = name;
  32         this.parameterTypes = parameterTypes;
  33         createTable();
  34     }
  35
  36     private void createTable() {
  37         this.table = newVar("table" + name,
  38                 Types.apply(ERuleset.MSet, Types.tuple(parameterTypes)));
  39     }
  40
  41     public int getArity() {
  42         return parameterTypes.length;
  43     }
  44
  45     public String getName() {
  46         return name;
  47     }
  48
  49     @Override
  50     public TVar[] getTypeVariables() {
  51         return TVar.EMPTY_ARRAY;
  52     }
  53
  54     @Override
  55     public Type[] getParameterTypes() {
  56         return parameterTypes;
  57     }
  58
  59     @Override
  60     public double getSelectivity(int boundVariabes) {
  61         double s = 0.95;
  62         for(int i=0;i<parameterTypes.length;++i,boundVariabes>>=1)
  63             if( (boundVariabes&1) == 0 )
  64                 s *= 10.0;
  65         return s;
  66     }
  67
  68     @Override
  69     public int getRequiredVariablesMask() {
  70         return 0;
  71     }
  72
  73     private static final Name MSet_contains = Name.create("MSet", "contains");
  74     private static final Name EQ = Name.create("Prelude", "==");
  75     @Override
  76     public void generate(long location,
  77             QueryCompilationContext context,
  78             Type[] typeParameters, Variable[] parameters, int boundVariables) {
  79         if(table == null)
  80             throw new InternalCompilerError(location, "Variable table is undefined.");
  81         if(boundVariables + 1 == 1 << parameters.length)
  82             context.condition(apply(context, Types.PROC,
  83                     MSet_contains, Types.tuple(parameterTypes),
  84                     var(table),
  85                     tuple(vars(parameters))
  86                     ));
  87         else {
  88             Variable[] aux = new Variable[parameters.length];
  89             for(int i=0;i<parameters.length;++i)
  90                 if(((boundVariables>>i)&1) == 1)
  91                     aux[i] = new Variable("aux_" + parameters[i].getName(), parameters[i].getType());
  92                 else
  93                     aux[i] = parameters[i];
  94             Variable row = new Variable("row", Types.tuple(parameterTypes));
  95             for(int i=0;i<parameters.length;++i)
  96                 if(((boundVariables>>i)&1) == 1)
  97                     context.condition(apply(context, Types.NO_EFFECTS,
  98                             EQ, parameterTypes[i],
  99                             context.getEvidence(location, Types.pred(Types.EQ, parameterTypes[i])),
 100                             var(aux[i]),
 101                             var(parameters[i])
 102                             ));
 103             context.match(Expressions.tuple(Expressions.vars(aux)), new EVariable(row), false);
 104             context.iterateMSet(row, new EVariable(table));
 105         }
 106     }
 107
 108     @Override
 109     public String toString() {
 110         return name;
 111     }
 112 }