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.apply;
   4 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.newVar;
   5 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.tuple;
   6 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.var;
   7 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.vars;
   8
   9 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
  10 import org.simantics.scl.compiler.common.names.Name;
  11 import org.simantics.scl.compiler.elaboration.expressions.ERuleset;
  12 import org.simantics.scl.compiler.elaboration.expressions.EVariable;
  13 import org.simantics.scl.compiler.elaboration.expressions.Expressions;
  14 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  15 import org.simantics.scl.compiler.elaboration.query.compilation.QueryCompilationContext;
  16 import org.simantics.scl.compiler.types.TVar;
  17 import org.simantics.scl.compiler.types.Type;
  18 import org.simantics.scl.compiler.types.Types;
  19 import org.simantics.scl.compiler.types.kinds.Kinds;
  20
  21 public class LocalRelation extends AbstractRelation {
  22     String name;
  23     Type[] parameterTypes;
  24     public Variable table;
  25
  26     public LocalRelation(String name, int arity) {
  27         this.name = name;
  28         this.parameterTypes = new Type[arity];
  29         for(int i=0;i<arity;++i)
  30             parameterTypes[i] = Types.metaVar(Kinds.STAR);
  31         createTable();
  32     }
  33
  34     public LocalRelation(String name, Type[] parameterTypes) {
  35         this.name = name;
  36         this.parameterTypes = parameterTypes;
  37         createTable();
  38     }
  39
  40     private void createTable() {
  41         this.table = newVar("table" + name,
  42                 Types.apply(ERuleset.MSet, Types.tuple(parameterTypes)));
  43     }
  44
  45     public int getArity() {
  46         return parameterTypes.length;
  47     }
  48
  49     public String getName() {
  50         return name;
  51     }
  52
  53     @Override
  54     public TVar[] getTypeVariables() {
  55         return TVar.EMPTY_ARRAY;
  56     }
  57
  58     @Override
  59     public Type[] getParameterTypes() {
  60         return parameterTypes;
  61     }
  62
  63     @Override
  64     public double getSelectivity(int boundVariabes) {
  65         double s = 0.95;
  66         for(int i=0;i<parameterTypes.length;++i,boundVariabes>>=1)
  67             if( (boundVariabes&1) == 0 )
  68                 s *= 10.0;
  69         return s;
  70     }
  71
  72     @Override
  73     public int getRequiredVariablesMask() {
  74         return 0;
  75     }
  76
  77     private static final Name MSet_contains = Name.create("MSet", "contains");
  78     private static final Name EQ = Name.create("Prelude", "==");
  79     @Override
  80     public void generate(long location,
  81             QueryCompilationContext context,
  82             Type[] typeParameters, Variable[] parameters, int boundVariables) {
  83         if(table == null)
  84             throw new InternalCompilerError(location, "Variable table is undefined.");
  85         if(boundVariables + 1 == 1 << parameters.length)
  86             context.condition(apply(context, Types.PROC,
  87                     MSet_contains, Types.tuple(parameterTypes),
  88                     var(table),
  89                     tuple(vars(parameters))
  90                     ));
  91         else {
  92             Variable[] aux = new Variable[parameters.length];
  93             for(int i=0;i<parameters.length;++i)
  94                 if(((boundVariables>>i)&1) == 1)
  95                     aux[i] = new Variable("aux_" + parameters[i].getName(), parameters[i].getType());
  96                 else
  97                     aux[i] = parameters[i];
  98             Variable row = new Variable("row", Types.tuple(parameterTypes));
  99             for(int i=0;i<parameters.length;++i)
 100                 if(((boundVariables>>i)&1) == 1)
 101                     context.condition(apply(context, Types.NO_EFFECTS,
 102                             EQ, parameterTypes[i],
 103                             context.getEvidence(location, Types.pred(Types.EQ, parameterTypes[i])),
 104                             var(aux[i]),
 105                             var(parameters[i])
 106                             ));
 107             context.match(Expressions.tuple(Expressions.vars(aux)), new EVariable(row), false);
 108             context.iterateMSet(row, new EVariable(table));
 109         }
 110     }
 111
 112     @Override
 113     public String toString() {
 114         return name;
 115     }
 116 }