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