bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/elaboration/constraints2/ConstraintStore.java

   1 package org.simantics.scl.compiler.internal.elaboration.constraints2;
   2
   3 import java.util.ArrayList;
   4
   5 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
   6 import org.simantics.scl.compiler.elaboration.modules.TypeClass;
   7 import org.simantics.scl.compiler.types.TCon;
   8 import org.simantics.scl.compiler.types.TPred;
   9 import org.simantics.scl.compiler.types.TVar;
  10 import org.simantics.scl.compiler.types.Type;
  11 import org.simantics.scl.compiler.types.Types;
  12 import org.simantics.scl.compiler.types.util.TypeUnparsingContext;
  13
  14 import gnu.trove.map.hash.THashMap;
  15 import gnu.trove.procedure.TObjectProcedure;
  16
  17 class ConstraintStore {
  18
  19     private final ConstraintSolver solver;
  20     private final TypeClass typeClass;
  21     private final THashMap<Type, ArrayList<ConstraintHandle>> constraintsByHead =
  22             new THashMap<Type, ArrayList<ConstraintHandle>>();
  23     private final ArrayList<ConstraintHandle> constraintsWithoutHead =
  24             new ArrayList<ConstraintHandle>();
  25
  26     public ConstraintStore(ConstraintSolver solver, TCon typeClassCon) {
  27         this.solver = solver;
  28         this.typeClass = solver.environment.getTypeClass(typeClassCon);
  29         if(this.typeClass == null)
  30             throw new InternalCompilerError("Didn't find type class " + typeClassCon + ".");
  31     }
  32
  33     private ArrayList<ConstraintHandle> getConstraintListFor(TPred pred) {
  34         Type head = head(pred);
  35         if(head instanceof TCon || head instanceof TVar) {
  36             ArrayList<ConstraintHandle> result = constraintsByHead.get(head);
  37             if(result == null) {
  38                 result = new ArrayList<ConstraintHandle>(2);
  39                 constraintsByHead.put(head, result);
  40             }
  41             return result;
  42         }
  43         else
  44             return constraintsWithoutHead;
  45     }
  46
  47     public ConstraintHandle addConstraint(TPred pred, long demandLocation) {
  48         // Try to find an existing ConstraintHandle for the predicate
  49         ArrayList<ConstraintHandle> handles = getConstraintListFor(pred);
  50         for(ConstraintHandle handle : handles)
  51             if(equals(pred.parameters, handle.constraint.parameters))
  52                 return handle;
  53
  54         // Create a new ConstraintHandle
  55         ConstraintHandle handle = new ConstraintHandle(pred, demandLocation);
  56         handles.add(handle);
  57         addSuperDemands(handle);
  58         return handle;
  59     }
  60
  61     private void addSuperDemands(ConstraintHandle handle) {
  62         for(int i=0;i<typeClass.context.length;++i) {
  63             TPred superPred = (TPred)
  64                     typeClass.context[i].replace(typeClass.parameters, handle.constraint.parameters);
  65             ConstraintHandle superHandle = solver.addDemand(superPred, handle.demandLocation);
  66             superHandle.setResolution(new ConstraintResolution(
  67                     typeClass.superGenerators[i],  handle.constraint.parameters,
  68                     new ConstraintHandle[] {handle}, ConstraintResolution.SUPERCLASS_PRIORITY));
  69         }
  70     }
  71
  72     private static Type head(TPred pred) {
  73         return pred.parameters[0].head();
  74     }
  75
  76     private static boolean equals(Type[] a, Type[] b) {
  77         for(int i=0;i<a.length;++i)
  78             if(!Types.equals(a[i], b[i]))
  79                 return false;
  80         return true;
  81     }
  82
  83     public void print(final TypeUnparsingContext tuc) {
  84         constraintsByHead.forEachValue(new TObjectProcedure<ArrayList<ConstraintHandle>>() {
  85             @Override
  86             public boolean execute(ArrayList<ConstraintHandle> constraintHandles) {
  87                 for(ConstraintHandle constraintHandle : constraintHandles)
  88                     System.out.println(constraintHandle.toString(tuc));
  89                 return true;
  90             }
  91         });
  92         for(ConstraintHandle constraintHandle : constraintsWithoutHead)
  93             System.out.println(constraintHandle.toString(tuc));
  94     }
  95
  96 }