bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Expression.java

   1 package org.simantics.scl.compiler.elaboration.expressions;\r
   2 \r
   3 import gnu.trove.map.hash.TObjectIntHashMap;\r
   4 import gnu.trove.set.hash.THashSet;\r
   5 import gnu.trove.set.hash.TIntHashSet;\r
   6 \r
   7 import java.util.ArrayList;\r
   8 \r
   9 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;\r
  10 import org.simantics.scl.compiler.common.precedence.Precedence;\r
  11 import org.simantics.scl.compiler.elaboration.contexts.ReplaceContext;\r
  12 import org.simantics.scl.compiler.elaboration.contexts.SimplificationContext;\r
  13 import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;\r
  14 import org.simantics.scl.compiler.elaboration.contexts.TypingContext;\r
  15 import org.simantics.scl.compiler.elaboration.errors.NotPatternException;\r
  16 import org.simantics.scl.compiler.elaboration.expressions.lhstype.LhsType;\r
  17 import org.simantics.scl.compiler.elaboration.expressions.lhstype.PatternMatchingLhs;\r
  18 import org.simantics.scl.compiler.elaboration.expressions.printing.ExpressionToStringVisitor;\r
  19 import org.simantics.scl.compiler.elaboration.query.QAtom;\r
  20 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;\r
  21 import org.simantics.scl.compiler.environment.Environment;\r
  22 import org.simantics.scl.compiler.internal.codegen.references.IVal;\r
  23 import org.simantics.scl.compiler.internal.codegen.writer.CodeWriter;\r
  24 import org.simantics.scl.compiler.internal.elaboration.decomposed.DecomposedExpression;\r
  25 import org.simantics.scl.compiler.internal.elaboration.utils.ExpressionDecorator;\r
  26 import org.simantics.scl.compiler.internal.interpreted.IExpression;\r
  27 import org.simantics.scl.compiler.internal.parsing.Symbol;\r
  28 import org.simantics.scl.compiler.top.ExpressionInterpretationContext;\r
  29 import org.simantics.scl.compiler.types.TForAll;\r
  30 import org.simantics.scl.compiler.types.TFun;\r
  31 import org.simantics.scl.compiler.types.TPred;\r
  32 import org.simantics.scl.compiler.types.TVar;\r
  33 import org.simantics.scl.compiler.types.Type;\r
  34 import org.simantics.scl.compiler.types.Types;\r
  35 import org.simantics.scl.compiler.types.exceptions.MatchException;\r
  36 import org.simantics.scl.compiler.types.kinds.Kinds;\r
  37 import org.simantics.scl.compiler.types.util.Typed;\r
  38 \r
  39 public abstract class Expression extends Symbol implements Typed {\r
  40     public static final Expression[] EMPTY_ARRAY = new Expression[0];\r
  41     \r
  42     transient\r
  43     private Type type;\r
  44     \r
  45     public Expression() {\r
  46     }\r
  47     \r
  48     public Expression(long loc) {\r
  49         this.location = loc;\r
  50     }\r
  51         \r
  52     @Override\r
  53     public Type getType() {\r
  54         if(type == null) {\r
  55             try {\r
  56                 updateType();\r
  57             } catch (MatchException e) {\r
  58                 throw new InternalCompilerError(e);\r
  59             }\r
  60             if(type == null)\r
  61                 throw new InternalCompilerError(getClass().getSimpleName() + \r
  62                         ".updateType couldn't compute its type.");\r
  63         }\r
  64         return type;\r
  65     }\r
  66 \r
  67     public void setType(Type type) {\r
  68         if(type == null)\r
  69             throw new NullPointerException();\r
  70         this.type = type;\r
  71     }\r
  72         \r
  73         /**\r
  74          * Infers the type of the expression without any context. Adds type\r
  75      * applications and lambdas if needed.       \r
  76          */\r
  77     public Expression inferType(TypingContext context) {\r
  78         return checkBasicType(context, Types.metaVar(Kinds.STAR));\r
  79     }\r
  80         \r
  81         public Expression checkBasicType(TypingContext context, Type requiredType) {\r
  82             return context.subsume(inferType(context), requiredType);\r
  83         }\r
  84         \r
  85         /**\r
  86          * Checks the type of the expression against the given type. Adds type\r
  87          * applications and lambdas if needed.\r
  88          */\r
  89         public final Expression checkType(TypingContext context, Type requiredType) {\r
  90             //System.out.println("checkType: " + this + " :: " + requiredType);\r
  91             if(!context.isInPattern()) {\r
  92                 requiredType = Types.weakCanonical(requiredType);\r
  93             if(requiredType instanceof TForAll) {\r
  94                 TForAll forAll = (TForAll)requiredType;\r
  95                 TVar var = forAll.var;\r
  96                 TVar newVar = Types.var(var.getKind());\r
  97                 requiredType = Types.canonical(forAll.type).replace(var, newVar);\r
  98                 return new ELambdaType(new TVar[] {newVar}, checkType(context, requiredType));\r
  99             }\r
 100             while(requiredType instanceof TFun) {\r
 101                 TFun fun = (TFun)requiredType;\r
 102                 if(fun.domain instanceof TPred) { // No need to canonicalize\r
 103                     ArrayList<Variable> constraints = new ArrayList<Variable>(2);\r
 104                     while(true) {\r
 105                         constraints.add(new Variable("constraint", fun.domain));\r
 106                         requiredType = Types.canonical(fun.range);\r
 107                         if(!(requiredType instanceof TFun))\r
 108                             break;\r
 109                         fun = (TFun)requiredType;\r
 110                         if(!(fun.domain instanceof TPred))\r
 111                             break;\r
 112                     }\r
 113                     context.pushConstraintFrame(constraints.toArray(new Variable[constraints.size()]));\r
 114                     Expression expression = checkType(context, requiredType);\r
 115                     context.popConstraintFrame();\r
 116                     for(int i=constraints.size()-1;i>=0;--i)\r
 117                         expression = new ESimpleLambda(constraints.get(i), expression);\r
 118                     return expression;\r
 119                 }\r
 120                 else if(fun.domain == Types.PUNIT) {\r
 121                     context.pushEffectUpperBound(location, fun.effect);\r
 122                     Expression expr = checkType(context, fun.range);\r
 123                     context.popEffectUpperBound();       \r
 124                     \r
 125                     // Wrap\r
 126                     Variable var = new Variable("punit", Types.PUNIT);\r
 127                     return new ESimpleLambda(location, var, fun.effect, expr);\r
 128                 }\r
 129                 else\r
 130                     break;\r
 131             }\r
 132             }\r
 133             return checkBasicType(context, requiredType); \r
 134         }\r
 135 \r
 136         public abstract void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs);\r
 137         public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);\r
 138         public abstract void forVariables(VariableProcedure procedure);\r
 139         \r
 140         public Expression decomposeMatching() {\r
 141         return this;\r
 142     }\r
 143 \r
 144         public String toString() {\r
 145             StringBuilder b = new StringBuilder();\r
 146             ExpressionToStringVisitor visitor = new ExpressionToStringVisitor(b);\r
 147             accept(visitor);\r
 148             return b.toString();\r
 149     }\r
 150 \r
 151         protected abstract void updateType() throws MatchException;\r
 152         \r
 153         public static class TypeValidationException extends Exception {\r
 154         private static final long serialVersionUID = 3181298127162041248L;  \r
 155         \r
 156         long loc;\r
 157 \r
 158         public TypeValidationException(long loc) {\r
 159             this.loc = loc;\r
 160         }\r
 161         \r
 162         public long getLoc() {\r
 163             return loc;\r
 164         }\r
 165 \r
 166         public TypeValidationException(long loc, Throwable cause) {\r
 167             super(cause);\r
 168             this.loc = loc;\r
 169         }\r
 170     }\r
 171     \r
 172     public static void assertEquals(long loc, Type a, Type b) throws TypeValidationException {\r
 173         if(!Types.equals(a, b))\r
 174             throw new TypeValidationException(loc);\r
 175     }\r
 176 \r
 177         public abstract IVal toVal(Environment env, CodeWriter w);\r
 178                 \r
 179         public Expression closure(TVar ... vars) {\r
 180             if(vars.length == 0)\r
 181             return this;\r
 182         return new ELambdaType(vars, this);\r
 183         }\r
 184     \r
 185     public abstract void collectFreeVariables(THashSet<Variable> vars);\r
 186     \r
 187     public Expression simplify(SimplificationContext context) {\r
 188         System.out.println("#############################");\r
 189         System.out.println(this);\r
 190         throw new InternalCompilerError(location, getClass().getSimpleName() + " does not support simplify method.");\r
 191     }\r
 192 \r
 193     public abstract Expression resolve(TranslationContext context);\r
 194     \r
 195     /**\r
 196      * Returns head of the pattern.\r
 197      */\r
 198     public EVar getPatternHead() throws NotPatternException {\r
 199         throw new NotPatternException(this);\r
 200     }\r
 201     \r
 202     public LhsType getLhsType() throws NotPatternException {\r
 203         throw new NotPatternException(this);\r
 204     }\r
 205 \r
 206     protected void collectVariableNames(PatternMatchingLhs lhsType) throws NotPatternException {\r
 207         throw new NotPatternException(this);\r
 208     }\r
 209 \r
 210     public void getParameters(TranslationContext translationContext,\r
 211             ArrayList<Expression> parameters) {\r
 212         throw new InternalCompilerError("Class " + getClass().getSimpleName() + " does not support getParameters.");        \r
 213     }\r
 214 \r
 215     public Expression resolveAsPattern(TranslationContext context) {\r
 216         context.getErrorLog().log(location, "Pattern was expected here.");\r
 217         return new EError();\r
 218     }\r
 219 \r
 220     public void removeFreeVariables(THashSet<Variable> vars) {\r
 221         throw new InternalCompilerError(getClass().getSimpleName() + " is not a pattern.");\r
 222     }\r
 223     \r
 224     public Expression checkTypeAsPattern(TypingContext context, Type requiredType) {\r
 225         if(context.isInPattern())\r
 226             throw new InternalCompilerError("Already in a pattern.");\r
 227         context.setInPattern(true);\r
 228         Expression expression = checkType(context, requiredType);\r
 229         context.setInPattern(false);\r
 230         return expression;\r
 231     }\r
 232 \r
 233     public THashSet<Variable> getFreeVariables() {\r
 234         THashSet<Variable> result = new THashSet<Variable>();\r
 235         collectFreeVariables(result);\r
 236         return result;\r
 237     }    \r
 238 \r
 239     public static Expression[] concat(Expression[] a, Expression[] b) {\r
 240         if(a.length == 0)\r
 241             return b;\r
 242         if(b.length == 0)\r
 243             return a;\r
 244         Expression[] result = new Expression[a.length + b.length];\r
 245         for(int i=0;i<a.length;++i)\r
 246             result[i] = a[i];\r
 247         for(int i=0;i<b.length;++i)\r
 248             result[i+a.length] = b[i];\r
 249         return result;\r
 250     }\r
 251 \r
 252     public Expression replace(ReplaceContext context) {\r
 253         throw new InternalCompilerError(getClass().getSimpleName() + " does not support replace.");\r
 254     }\r
 255     \r
 256     public static Expression[] replace(ReplaceContext context, Expression[] expressions) {\r
 257         Expression[] result = new Expression[expressions.length];\r
 258         for(int i=0;i<expressions.length;++i)\r
 259             result[i] = expressions[i].replace(context);\r
 260         return result;\r
 261     }\r
 262     \r
 263     public Expression copy() {\r
 264         return replace(new ReplaceContext(null));\r
 265     }\r
 266     \r
 267     public Expression copy(TypingContext typingContext) {\r
 268         return replace(new ReplaceContext(typingContext));\r
 269     }\r
 270 \r
 271     public abstract void setLocationDeep(long loc);\r
 272 \r
 273     public Expression replaceInPattern(ReplaceContext context) {\r
 274         context.inPattern = true;\r
 275         Expression result = replace(context);\r
 276         context.inPattern = false;\r
 277         return result;\r
 278     }\r
 279 \r
 280     public int getFunctionDefinitionArity() throws NotPatternException {\r
 281         throw new NotPatternException(this);\r
 282     }\r
 283     \r
 284     public IVal lambdaToVal(Environment env, CodeWriter w) {\r
 285         DecomposedExpression decomposed = DecomposedExpression.decompose(this);\r
 286         CodeWriter newW = w.createFunction(decomposed.typeParameters, decomposed.effect, decomposed.returnType, decomposed.parameterTypes);\r
 287         IVal[] parameters = newW.getParameters();\r
 288         IVal functionVal = newW.getFunction().getTarget();\r
 289         for(int i=0;i<parameters.length;++i)\r
 290             decomposed.parameters[i].setVal(parameters[i]);\r
 291         newW.return_(decomposed.body.toVal(env, newW));\r
 292         return functionVal;\r
 293     }\r
 294     \r
 295     public IExpression toIExpression(ExpressionInterpretationContext context) {\r
 296         throw new UnsupportedOperationException();\r
 297     }\r
 298     \r
 299     public static IExpression[] toIExpressions(ExpressionInterpretationContext target, Expression[] expressions) {\r
 300         IExpression[] result = new IExpression[expressions.length];\r
 301         for(int i=0;i<expressions.length;++i)\r
 302             result[i] = expressions[i].toIExpression(target);\r
 303         return result;\r
 304     }\r
 305     \r
 306     public Expression applyType(Type type) {\r
 307         return new EApplyType(location, this, type);\r
 308     }\r
 309     \r
 310     public abstract Expression decorate(ExpressionDecorator decorator);\r
 311 \r
 312         public boolean isEffectful() {\r
 313                 return true;\r
 314         }\r
 315 \r
 316     public boolean isFunctionPattern() {\r
 317         return false;\r
 318     }\r
 319 \r
 320     public boolean isConstructorApplication() {\r
 321         return false;\r
 322     }\r
 323     \r
 324     public abstract void collectEffects(THashSet<Type> effects);\r
 325     \r
 326     public Type getEffect() {\r
 327         THashSet<Type> effects = new THashSet<Type>();\r
 328         collectEffects(effects);\r
 329         return Types.union(effects.toArray(new Type[effects.size()]));\r
 330     }\r
 331     \r
 332     public abstract void accept(ExpressionVisitor visitor);\r
 333     \r
 334     public void collectRelationRefs(\r
 335             final TObjectIntHashMap<SCLRelation> allRefs, final TIntHashSet refs) {\r
 336         accept(new StandardExpressionVisitor() {\r
 337             @Override\r
 338             public void visit(QAtom query) {\r
 339                 int id = allRefs.get(query.relation);\r
 340                 if(id >= 0)\r
 341                     refs.add(id);\r
 342             }\r
 343         });\r
 344     }\r
 345 \r
 346     public boolean isFunctionDefinitionLhs() {\r
 347         return false;\r
 348     }\r
 349 \r
 350     public Precedence getPrecedence() {\r
 351         return Precedence.DEFAULT;\r
 352     }\r
 353 \r
 354     public boolean isPattern(int arity) {\r
 355         return false;\r
 356     }\r
 357     \r
 358     public abstract Expression accept(ExpressionTransformer transformer);\r
 359 }\r