gerrit.simantics Code Review - simantics/platform.git/blob

   1 package org.simantics.scl.compiler.elaboration.expressions;
   2
   3 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.Just;
   4 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.addInteger;
   5 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.apply;
   6 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.as;
   7 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.if_;
   8 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.integer;
   9 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.isZeroInteger;
  10 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.lambda;
  11 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.let;
  12 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.letRec;
  13 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.matchWithDefault;
  14 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.newVar;
  15 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.seq;
  16 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.tuple;
  17 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.var;
  18 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.vars;
  19
  20 import java.util.ArrayList;
  21 import java.util.Set;
  22
  23 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
  24 import org.simantics.scl.compiler.common.names.Names;
  25 import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
  26 import org.simantics.scl.compiler.elaboration.contexts.TypingContext;
  27 import org.simantics.scl.compiler.elaboration.expressions.printing.ExpressionToStringVisitor;
  28 import org.simantics.scl.compiler.elaboration.query.Query;
  29 import org.simantics.scl.compiler.elaboration.query.Query.Diff;
  30 import org.simantics.scl.compiler.elaboration.query.Query.Diffable;
  31 import org.simantics.scl.compiler.elaboration.query.compilation.DerivateException;
  32 import org.simantics.scl.compiler.elaboration.relations.LocalRelation;
  33 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
  34 import org.simantics.scl.compiler.errors.Locations;
  35 import org.simantics.scl.compiler.internal.elaboration.utils.ForcedClosure;
  36 import org.simantics.scl.compiler.internal.elaboration.utils.StronglyConnectedComponents;
  37 import org.simantics.scl.compiler.top.SCLCompilerConfiguration;
  38 import org.simantics.scl.compiler.types.Type;
  39 import org.simantics.scl.compiler.types.Types;
  40 import org.simantics.scl.compiler.types.exceptions.MatchException;
  41 import org.simantics.scl.compiler.types.kinds.Kinds;
  42
  43 import gnu.trove.impl.Constants;
  44 import gnu.trove.map.hash.THashMap;
  45 import gnu.trove.map.hash.TObjectIntHashMap;
  46 import gnu.trove.set.hash.THashSet;
  47 import gnu.trove.set.hash.TIntHashSet;
  48
  49 public class ERuleset extends SimplifiableExpression {
  50     LocalRelation[] relations;
  51     DatalogRule[] rules;
  52     Expression in;
  53
  54     public ERuleset(LocalRelation[] relations, DatalogRule[] rules, Expression in) {
  55         this.relations = relations;
  56         this.rules = rules;
  57         this.in = in;
  58     }
  59
  60     public static class DatalogRule {
  61         public long location;
  62         public LocalRelation headRelation;
  63         public Expression[] headParameters;
  64         public Query body;
  65         public Variable[] variables;
  66
  67         public DatalogRule(LocalRelation headRelation, Expression[] headParameters,
  68                 Query body) {
  69             this.headRelation = headRelation;
  70             this.headParameters = headParameters;
  71             this.body = body;
  72         }
  73
  74         public DatalogRule(long location, LocalRelation headRelation, Expression[] headParameters,
  75                 Query body, Variable[] variables) {
  76             this.location = location;
  77             this.headRelation = headRelation;
  78             this.headParameters = headParameters;
  79             this.body = body;
  80             this.variables = variables;
  81         }
  82
  83         public void setLocationDeep(long loc) {
  84             this.location = loc;
  85             for(Expression parameter : headParameters)
  86                 parameter.setLocationDeep(loc);
  87             body.setLocationDeep(loc);
  88         }
  89
  90         @Override
  91         public String toString() {
  92             StringBuilder b = new StringBuilder();
  93             ExpressionToStringVisitor visitor = new ExpressionToStringVisitor(b);
  94             visitor.visit(this);
  95             return b.toString();
  96         }
  97     }
  98
  99     private void checkRuleTypes(TypingContext context) {
 100         // Create relation variables
 101         for(DatalogRule rule : rules) {
 102             Type[] parameterTypes =  rule.headRelation.getParameterTypes();
 103             Expression[] parameters = rule.headParameters;
 104             for(Variable variable : rule.variables)
 105                 variable.setType(Types.metaVar(Kinds.STAR));
 106             for(int i=0;i<parameters.length;++i)
 107                 parameters[i] = parameters[i].checkType(context, parameterTypes[i]);
 108             rule.body.checkType(context);
 109         }
 110     }
 111
 112     @Override
 113     public Expression checkBasicType(TypingContext context, Type requiredType) {
 114         checkRuleTypes(context);
 115         in = in.checkBasicType(context, requiredType);
 116         return compile(context);
 117     }
 118
 119     @Override
 120     public Expression inferType(TypingContext context) {
 121         checkRuleTypes(context);
 122         in = in.inferType(context);
 123         return compile(context);
 124     }
 125
 126     @Override
 127     public Expression checkIgnoredType(TypingContext context) {
 128         checkRuleTypes(context);
 129         in = in.checkIgnoredType(context);
 130         return compile(context);
 131     }
 132
 133     @Override
 134     public void collectFreeVariables(THashSet<Variable> vars) {
 135         for(DatalogRule rule : rules) {
 136             for(Expression parameter : rule.headParameters)
 137                 parameter.collectFreeVariables(vars);
 138             rule.body.collectFreeVariables(vars);
 139             for(Variable var : rule.variables)
 140                 vars.remove(var);
 141         }
 142         in.collectFreeVariables(vars);
 143     }
 144
 145     @Override
 146     public void collectVars(TObjectIntHashMap<Variable> allVars,
 147             TIntHashSet vars) {
 148         for(DatalogRule rule : rules) {
 149             for(Expression parameter : rule.headParameters)
 150                 parameter.collectVars(allVars, vars);
 151             rule.body.collectVars(allVars, vars);
 152         }
 153         in.collectVars(allVars, vars);
 154     }
 155
 156     @Override
 157     public Expression resolve(TranslationContext context) {
 158         throw new InternalCompilerError();
 159     }
 160
 161     static class LocalRelationAux {
 162         Variable handleFunc;
 163     }
 164
 165     public Expression compile(TypingContext context) {
 166         // Create a map from relations to their ids
 167         TObjectIntHashMap<SCLRelation> relationsToIds = new TObjectIntHashMap<SCLRelation>(relations.length,
 168                 Constants.DEFAULT_LOAD_FACTOR, -1);
 169         for(int i=0;i<relations.length;++i)
 170             relationsToIds.put(relations[i], i);
 171
 172         // Create a table from relations to the other relations they depend on
 173         TIntHashSet[] refsSets = new TIntHashSet[relations.length];
 174         int setCapacity = Math.min(Constants.DEFAULT_CAPACITY, relations.length);
 175         for(int i=0;i<relations.length;++i)
 176             refsSets[i] = new TIntHashSet(setCapacity);
 177
 178         for(DatalogRule rule : rules) {
 179             int headRelationId = relationsToIds.get(rule.headRelation);
 180             TIntHashSet refsSet = refsSets[headRelationId];
 181             rule.body.collectRelationRefs(relationsToIds, refsSet);
 182             for(Expression parameter : rule.headParameters)
 183                 parameter.collectRelationRefs(relationsToIds, refsSet);
 184         }
 185
 186         // Convert refsSets to an array
 187         final int[][] refs = new int[relations.length][];
 188         for(int i=0;i<relations.length;++i)
 189             refs[i] = refsSets[i].toArray();
 190
 191         // Find strongly connected components of the function refs
 192         final ArrayList<int[]> components = new ArrayList<int[]>();
 193
 194         new StronglyConnectedComponents(relations.length) {
 195             @Override
 196             protected void reportComponent(int[] component) {
 197                 components.add(component);
 198             }
 199
 200             @Override
 201             protected int[] findDependencies(int u) {
 202                 return refs[u];
 203             }
 204         }.findComponents();
 205
 206         // If there is just one component, compile it
 207         if(components.size() == 1) {
 208             return compileStratified(context);
 209         }
 210
 211         // Inverse of components array
 212         int[] strataPerRelation = new int[relations.length];
 213         for(int i=0;i<components.size();++i)
 214             for(int k : components.get(i))
 215                 strataPerRelation[k] = i;
 216
 217         // Collects rules belonging to each strata
 218         @SuppressWarnings("unchecked")
 219         ArrayList<DatalogRule>[] rulesPerStrata = new ArrayList[components.size()];
 220         for(int i=0;i<components.size();++i)
 221             rulesPerStrata[i] = new ArrayList<DatalogRule>();
 222         for(DatalogRule rule : rules) {
 223             int stratum = strataPerRelation[relationsToIds.get(rule.headRelation)];
 224             rulesPerStrata[stratum].add(rule);
 225         }
 226
 227         // Create stratified system
 228         Expression cur = this.in;
 229         for(int stratum=components.size()-1;stratum >= 0;--stratum) {
 230             int[] cs = components.get(stratum);
 231             LocalRelation[] curRelations = new LocalRelation[cs.length];
 232             for(int i=0;i<cs.length;++i)
 233                 curRelations[i] = relations[cs[i]];
 234             ArrayList<DatalogRule> curRules = rulesPerStrata[stratum];
 235             cur = new ERuleset(curRelations, curRules.toArray(new DatalogRule[curRules.size()]), cur).compileStratified(context);
 236         }
 237         return cur;
 238     }
 239
 240     private Expression compileStratified(TypingContext context) {
 241         Expression continuation = Expressions.tuple();
 242
 243         // Create stacks
 244         Variable[] stacks = new Variable[relations.length];
 245         for(int i=0;i<relations.length;++i) {
 246             LocalRelation relation = relations[i];
 247             Type[] parameterTypes = relation.getParameterTypes();
 248             stacks[i] = newVar("stack" + relation.getName(),
 249                     Types.apply(Names.MList_T, Types.tuple(parameterTypes))
 250                     );
 251         }
 252
 253         // Simplify subexpressions and collect derivatives
 254         THashMap<LocalRelation, Diffable> diffables = new THashMap<LocalRelation, Diffable>(relations.length);
 255         for(int i=0;i<relations.length;++i) {
 256             LocalRelation relation = relations[i];
 257             Type[] parameterTypes = relation.getParameterTypes();
 258             Variable[] parameters = new Variable[parameterTypes.length];
 259             for(int j=0;j<parameterTypes.length;++j)
 260                 parameters[j] = new Variable("p" + j, parameterTypes[j]);
 261             diffables.put(relations[i], new Diffable(i, relation, parameters));
 262         }
 263         @SuppressWarnings("unchecked")
 264         ArrayList<Expression>[] updateExpressions = (ArrayList<Expression>[])new ArrayList[relations.length];
 265         for(int i=0;i<relations.length;++i)
 266             updateExpressions[i] = new ArrayList<Expression>(2);
 267         ArrayList<Expression> seedExpressions = new ArrayList<Expression>();
 268         for(DatalogRule rule : rules) {
 269             int id = diffables.get(rule.headRelation).id;
 270             Expression appendExp = apply(context.getCompilationContext(), Types.PROC, Names.MList_add, Types.tuple(rule.headRelation.getParameterTypes()),
 271                     var(stacks[id]),
 272                     tuple(rule.headParameters)
 273                     );
 274             Diff[] diffs;
 275             try {
 276                 diffs = rule.body.derivate(diffables);
 277             } catch(DerivateException e) {
 278                 context.getErrorLog().log(e.location, "Recursion must not contain negations or aggragates.");
 279                 return new EError();
 280             }
 281             for(Diff diff : diffs)
 282                 updateExpressions[diff.id].add(((EWhen)new EWhen(rule.location, diff.query, appendExp, rule.variables).copy(context)).compile(context));
 283             if(diffs.length == 0)
 284                 seedExpressions.add(((EWhen)new EWhen(rule.location, rule.body, appendExp, rule.variables).copy(context)).compile(context));
 285             else {
 286                 Query query = rule.body.removeRelations((Set<SCLRelation>)(Set)diffables.keySet());
 287                 if(query != Query.EMPTY_QUERY)
 288                     seedExpressions.add(((EWhen)new EWhen(location, query, appendExp, rule.variables).copy(context)).compile(context));
 289             }
 290         }
 291
 292         // Iterative solving of relations
 293
 294         Variable[] loops = new Variable[relations.length];
 295         for(int i=0;i<loops.length;++i)
 296             loops[i] = newVar("loop" + relations[i].getName(), Types.functionE(Types.INTEGER, Types.PROC, Types.UNIT));
 297         continuation = seq(apply(Types.PROC, var(loops[0]), integer(relations.length-1)), continuation);
 298
 299         Expression[] loopDefs = new Expression[relations.length];
 300         for(int i=0;i<relations.length;++i) {
 301             LocalRelation relation = relations[i];
 302             Type[] parameterTypes = relation.getParameterTypes();
 303             Variable[] parameters = diffables.get(relation).parameters;
 304
 305             Variable counter = newVar("counter", Types.INTEGER);
 306
 307             Type rowType = Types.tuple(parameterTypes);
 308             Variable row = newVar("row", rowType);
 309
 310             Expression handleRow = tuple();
 311             for(Expression updateExpression : updateExpressions[i])
 312                 handleRow = seq(updateExpression, handleRow);
 313             handleRow = if_(
 314                     apply(context.getCompilationContext(), Types.PROC, Names.MSet_add, rowType,
 315                             var(relation.table), var(row)),
 316                     handleRow,
 317                     tuple()
 318                     );
 319             handleRow = seq(handleRow, apply(Types.PROC, var(loops[i]), integer(relations.length-1)));
 320             Expression failure =
 321                     if_(isZeroInteger(var(counter)),
 322                         tuple(),
 323                         apply(Types.PROC, var(loops[(i+1)%relations.length]), addInteger(var(counter), integer(-1)))
 324                        );
 325             Expression body = matchWithDefault(
 326                     apply(context.getCompilationContext(), Types.PROC, Names.MList_removeLast, rowType, var(stacks[i])),
 327                     Just(as(row, tuple(vars(parameters)))), handleRow,
 328                     failure);
 329
 330             loopDefs[i] = lambda(Types.PROC, counter, body);
 331         }
 332         continuation = letRec(loops, loopDefs, continuation);
 333
 334         // Seed relations
 335         for(Expression seedExpression : seedExpressions)
 336             continuation = seq(seedExpression, continuation);
 337
 338         // Create stacks
 339         for(int i=0;i<stacks.length;++i)
 340             continuation = let(stacks[i],
 341                     apply(context.getCompilationContext(), Types.PROC, Names.MList_create, Types.tuple(relations[i].getParameterTypes()), tuple()),
 342                     continuation);
 343
 344         continuation = ForcedClosure.forceClosure(continuation, SCLCompilerConfiguration.EVERY_DATALOG_STRATUM_IN_SEPARATE_METHOD);
 345
 346         // Create relations
 347         for(LocalRelation relation : relations)
 348             continuation = let(relation.table,
 349                     apply(context.getCompilationContext(), Types.PROC, Names.MSet_create, Types.tuple(relation.getParameterTypes()), tuple()),
 350                     continuation);
 351
 352         return seq(continuation, in);
 353     }
 354
 355     @Override
 356     protected void updateType() throws MatchException {
 357         setType(in.getType());
 358     }
 359
 360     @Override
 361     public void setLocationDeep(long loc) {
 362         if(location == Locations.NO_LOCATION) {
 363             location = loc;
 364             for(DatalogRule rule : rules)
 365                 rule.setLocationDeep(loc);
 366         }
 367     }
 368
 369     @Override
 370     public void accept(ExpressionVisitor visitor) {
 371         visitor.visit(this);
 372     }
 373
 374     public DatalogRule[] getRules() {
 375         return rules;
 376     }
 377
 378     public Expression getIn() {
 379         return in;
 380     }
 381
 382     @Override
 383     public Expression accept(ExpressionTransformer transformer) {
 384         return transformer.transform(this);
 385     }
 386
 387 }