400x faster with linear hashing of the hash map entries (#8425)

Fixes #5233 by removing `EconomicMap` & co. and using plain old good _linear hashing_. Fixes #8090 by introducing `StorageEntry.removed()` rather than copying the builder on each removal.

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/meta/HashCodeNode.java

@@ -55,6 +55,8 @@ import org.enso.interpreter.runtime.scope.ModuleScope;
 import org.enso.interpreter.runtime.state.State;
 import org.enso.polyglot.common_utils.Core_Text_Utils;
 
+import com.oracle.truffle.api.dsl.Fallback;
+
 /**
  * Implements {@code hash_code} functionality.
  *
@@ -630,6 +632,11 @@ public abstract class HashCodeNode extends Node {
     return hashCodeNode.execute(interop.toDisplayString(hostFunction));
   }
 
+  @Fallback
+  long fallbackConstant(Object any) {
+    return 5343210;
+  }
+
   static boolean isAtom(Object object) {
     return object instanceof Atom;
   }

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/EnsoHashMap.java

@@ -2,6 +2,7 @@ package org.enso.interpreter.runtime.data.hash;
 
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.dsl.Cached;
+import com.oracle.truffle.api.dsl.Cached.Shared;
 import com.oracle.truffle.api.interop.InteropLibrary;
 import com.oracle.truffle.api.interop.UnknownKeyException;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
@@ -16,7 +17,9 @@ import org.enso.interpreter.runtime.EnsoContext;
 import org.enso.interpreter.runtime.data.EnsoObject;
 import org.enso.interpreter.runtime.data.Type;
 import org.enso.interpreter.runtime.data.hash.EnsoHashMapBuilder.StorageEntry;
+import org.enso.interpreter.runtime.data.text.Text;
 import org.enso.interpreter.runtime.data.vector.ArrayLikeHelpers;
+import org.enso.interpreter.runtime.error.PanicException;
 import org.enso.interpreter.runtime.library.dispatch.TypesLibrary;
 
 /**
@@ -34,36 +37,32 @@ import org.enso.interpreter.runtime.library.dispatch.TypesLibrary;
 @Builtin(stdlibName = "Standard.Base.Data.Map.Map", name = "Map")
 public final class EnsoHashMap implements EnsoObject {
   private final EnsoHashMapBuilder mapBuilder;
-  /**
-   * Size of this Map. Basically an index into {@link EnsoHashMapBuilder}'s storage. See {@link
-   * #isEntryInThisMap(StorageEntry)}.
-   */
-  private final int snapshotSize;
-  /**
-   * True iff {@code insert} method was already called. If insert was already called, and we are
-   * calling {@code insert} again, the {@link #mapBuilder} should be duplicated for the newly
-   * created Map.
-   */
-  private boolean insertCalled;
+  private final int generation;
+  private final int size;
 
   private Object cachedVectorRepresentation;
 
-  private EnsoHashMap(EnsoHashMapBuilder mapBuilder, int snapshotSize) {
+  private EnsoHashMap(EnsoHashMapBuilder mapBuilder) {
     this.mapBuilder = mapBuilder;
-    this.snapshotSize = snapshotSize;
-    assert snapshotSize <= mapBuilder.getSize();
+    this.generation = mapBuilder.generation();
+    this.size = mapBuilder.size();
   }
 
-  static EnsoHashMap createWithBuilder(EnsoHashMapBuilder mapBuilder, int snapshotSize) {
-    return new EnsoHashMap(mapBuilder, snapshotSize);
+  static EnsoHashMap createWithBuilder(EnsoHashMapBuilder mapBuilder) {
+    return new EnsoHashMap(mapBuilder);
   }
 
-  static EnsoHashMap createEmpty(HashCodeNode hashCodeNode, EqualsNode equalsNode) {
-    return new EnsoHashMap(EnsoHashMapBuilder.create(hashCodeNode, equalsNode), 0);
+  static EnsoHashMap createEmpty() {
+    return new EnsoHashMap(EnsoHashMapBuilder.create());
   }
 
-  EnsoHashMapBuilder getMapBuilder() {
-    return mapBuilder;
+  EnsoHashMapBuilder getMapBuilder(
+      boolean readOnly, HashCodeNode hashCodeNode, EqualsNode equalsNode) {
+    if (readOnly) {
+      return mapBuilder;
+    } else {
+      return mapBuilder.asModifiable(generation, hashCodeNode, equalsNode);
+    }
   }
 
   Object getCachedVectorRepresentation() {
@@ -72,37 +71,24 @@ public final class EnsoHashMap implements EnsoObject {
 
   Object getCachedVectorRepresentation(ConditionProfile isNotCachedProfile) {
     if (isNotCachedProfile.profile(cachedVectorRepresentation == null)) {
-      Object[] keys = new Object[snapshotSize];
-      Object[] values = new Object[snapshotSize];
-      int arrIdx = 0;
-      for (StorageEntry entry : mapBuilder.getStorage().getValues()) {
-        if (entry.index() < snapshotSize) {
-          keys[arrIdx] = entry.key();
-          values[arrIdx] = entry.value();
-          arrIdx++;
-        }
+      var keys = new Object[size];
+      var values = new Object[size];
+      var at = 0;
+      for (var entry : mapBuilder.getEntries(generation, size)) {
+        keys[at] = entry.key();
+        values[at] = entry.value();
+        at++;
       }
-      cachedVectorRepresentation =
-          ArrayLikeHelpers.asVectorFromArray(
-              HashEntriesVector.createFromKeysAndValues(keys, values));
+      var pairs = HashEntriesVector.createFromKeysAndValues(keys, values);
+      cachedVectorRepresentation = ArrayLikeHelpers.asVectorFromArray(pairs);
     }
     return cachedVectorRepresentation;
   }
 
-  public boolean isInsertCalled() {
-    return insertCalled;
-  }
-
-  public void setInsertCalled() {
-    assert !insertCalled : "setInsertCalled should be called at most once";
-    insertCalled = true;
-  }
-
   @Builtin.Method
   @Builtin.Specialize
-  public static EnsoHashMap empty(
-      @Cached HashCodeNode hashCodeNode, @Cached EqualsNode equalsNode) {
-    return createEmpty(hashCodeNode, equalsNode);
+  public static EnsoHashMap empty() {
+    return createEmpty();
   }
 
   @ExportMessage
@@ -112,23 +98,34 @@ public final class EnsoHashMap implements EnsoObject {
 
   @ExportMessage
   int getHashSize() {
-    return snapshotSize;
+    return size;
   }
 
   @ExportMessage
-  boolean isHashEntryExisting(Object key) {
-    return isEntryInThisMap(mapBuilder.get(key));
+  boolean isHashEntryExisting(
+      Object key,
+      @Shared("hash") @Cached HashCodeNode hashCodeNode,
+      @Shared("equals") @Cached EqualsNode equalsNode) {
+    var entry = mapBuilder.get(key, generation, hashCodeNode, equalsNode);
+    return entry != null;
   }
 
   @ExportMessage
-  boolean isHashEntryReadable(Object key) {
-    return isHashEntryExisting(key);
+  boolean isHashEntryReadable(
+      Object key,
+      @Shared("hash") @Cached HashCodeNode hashCodeNode,
+      @Shared("equals") @Cached EqualsNode equalsNode) {
+    return isHashEntryExisting(key, hashCodeNode, equalsNode);
   }
 
   @ExportMessage
-  Object readHashValue(Object key) throws UnknownKeyException {
-    StorageEntry entry = mapBuilder.get(key);
-    if (isEntryInThisMap(entry)) {
+  Object readHashValue(
+      Object key,
+      @Shared("hash") @Cached HashCodeNode hashCodeNode,
+      @Shared("equals") @Cached EqualsNode equalsNode)
+      throws UnknownKeyException {
+    StorageEntry entry = mapBuilder.get(key, generation, hashCodeNode, equalsNode);
+    if (entry != null) {
       return entry.value();
     } else {
       throw UnknownKeyException.create(key);
@@ -140,7 +137,7 @@ public final class EnsoHashMap implements EnsoObject {
     try {
       return interop.getIterator(getCachedVectorRepresentation());
     } catch (UnsupportedMessageException e) {
-      throw new IllegalStateException(e);
+      throw new PanicException(Text.create(e.getMessage()), interop);
     }
   }
 
@@ -181,11 +178,9 @@ public final class EnsoHashMap implements EnsoObject {
     var sb = new StringBuilder();
     sb.append("{");
     boolean empty = true;
-    for (StorageEntry entry : mapBuilder.getStorage().getValues()) {
-      if (isEntryInThisMap(entry)) {
-        empty = false;
-        sb.append(entryToString(entry, useInterop)).append(", ");
-      }
+    for (StorageEntry entry : mapBuilder.getEntries(generation, size)) {
+      empty = false;
+      sb.append(entryToString(entry, useInterop)).append(", ");
     }
     if (!empty) {
       // Delete last comma
@@ -204,7 +199,7 @@ public final class EnsoHashMap implements EnsoObject {
         keyStr = interop.asString(interop.toDisplayString(entry.key()));
         valStr = interop.asString(interop.toDisplayString(entry.value()));
       } catch (UnsupportedMessageException e) {
-        throw new IllegalStateException("Unreachable", e);
+        throw new PanicException(Text.create(e.getMessage()), interop);
       }
     } else {
       keyStr = entry.key().toString();
@@ -212,8 +207,4 @@ public final class EnsoHashMap implements EnsoObject {
     }
     return keyStr + "=" + valStr;
   }
-
-  private boolean isEntryInThisMap(StorageEntry entry) {
-    return entry != null && entry.index() < snapshotSize;
-  }
 }

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/EnsoHashMapBuilder.java

@@ -1,193 +1,264 @@
 package org.enso.interpreter.runtime.data.hash;
 
-import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.Arrays;
+
 import org.enso.interpreter.node.expression.builtin.meta.EqualsNode;
 import org.enso.interpreter.node.expression.builtin.meta.HashCodeNode;
-import org.graalvm.collections.EconomicMap;
-import org.graalvm.collections.Equivalence;
+
+import com.oracle.truffle.api.CompilerDirectives;
 
 /**
- * A storage for a {@link EnsoHashMap}. For one builder, there may be many snapshots ({@link
- * EnsoHashMap}). There should be at most one snapshot for a given size. All the snapshots should
- * have size smaller than this builder size.
+ * A storage for a {@link EnsoHashMap}. For one builder, there may be many
+ * {@link EnsoHashMap} instances that serve as a snapshot.
+ *
+ * There should be at most one snapshot for a given generation. All the snapshots should
+ have generation smaller than this builder generation.
  */
-public final class EnsoHashMapBuilder {
-  private final EconomicMap<Object, StorageEntry> storage;
-  /** All entries stored by their sequential index. */
-  private final List<StorageEntry> sequentialEntries;
+final class EnsoHashMapBuilder {
+  /**
+  * Array of entries. It is only being added into. Both {@code put} and {@code remove}
+  * operations just add new entries into it using <em>linear hashing</em>.
+  */
+  private final StorageEntry[] byHash;
+/** number of entries in the {@code byHash} array. With every change to the builder,
+  * the generation increases by one. Once the generation reaches 75% of {@code byHash.length}
+  * it is time to <em>rehash</em> into new builder.
+  */
+  private int generation;
+  /** the actual number of entries in the builder at the latest {@code generation}.
+   * <ul>
+   *   <li>{@code put} of new key increases it</li>
+   *   <li>{@code put} over existing key doesn't change it</li>
+   *   <li>{@code remove} of a key decreases it</li>
+   * </ul>
+  */
+  private int actualSize;
 
-  private final HashCodeNode hashCodeNode;
-  private final EqualsNode equalsNode;
-  private int size;
-
-  private EnsoHashMapBuilder(HashCodeNode hashCodeNode, EqualsNode equalsNode) {
-    this.storage = EconomicMap.create(new StorageStrategy(equalsNode, hashCodeNode));
-    this.sequentialEntries = new ArrayList<>();
-    this.hashCodeNode = hashCodeNode;
-    this.equalsNode = equalsNode;
-  }
-
-  private EnsoHashMapBuilder(EnsoHashMapBuilder other, int numEntries) {
-    assert 0 < numEntries && numEntries <= other.size;
-    this.storage = EconomicMap.create(new StorageStrategy(other.equalsNode, other.hashCodeNode));
-    var entriesToBeDuplicated = other.sequentialEntries.subList(0, numEntries);
-    this.sequentialEntries = new ArrayList<>(entriesToBeDuplicated);
-    entriesToBeDuplicated.forEach(entry -> this.storage.put(entry.key, entry));
-    this.hashCodeNode = other.hashCodeNode;
-    this.equalsNode = other.equalsNode;
-    this.size = numEntries;
-  }
-
-  private EnsoHashMapBuilder(EnsoHashMapBuilder other) {
-    this.storage =
-        EconomicMap.create(
-            new StorageStrategy(other.equalsNode, other.hashCodeNode), other.storage);
-    this.sequentialEntries = new ArrayList<>(other.sequentialEntries);
-    this.hashCodeNode = other.hashCodeNode;
-    this.equalsNode = other.equalsNode;
-    this.size = other.size;
+  /** Creates an empty builder with given capacity. The capacity specifies
+   * the size of array of {@link StorageEntry} instances. The {@code put}
+   * and {@code remove} operations add entries into the array until it is
+   * 75% full.
+   */
+  private EnsoHashMapBuilder(int initialCapacity) {
+    this.byHash = new StorageEntry[initialCapacity];
   }
 
   /**
-   * Create a new builder with stored nodes.
-   *
-   * @param hashCodeNode Node that will be stored in the storage for invoking `hash_code` on keys.
-   * @param equalsNode Node that will be stored in the storage for invoking `==` on keys.
+   * Create a new builder with default size being {@code 11}.
    */
-  public static EnsoHashMapBuilder create(HashCodeNode hashCodeNode, EqualsNode equalsNode) {
-    return new EnsoHashMapBuilder(hashCodeNode, equalsNode);
+  public static EnsoHashMapBuilder create() {
+    return new EnsoHashMapBuilder(11);
   }
 
   /** Returns count of elements in the storage. */
-  public int getSize() {
-    return size;
+  public int generation() {
+    return generation;
   }
 
-  public EconomicMap<Object, StorageEntry> getStorage() {
-    return storage;
+  /** Returns the actual number of visible elements in current generation. */
+  public int size() {
+    return actualSize;
   }
 
-  /**
-   * Duplicates the MapBuilder with just first {@code numEntries} number of entries.
-   *
-   * @param numEntries Number of entries to take from this MapBuilder.
+  /** Provides access to all {@code StorageEntry} in this builder
+   * at given {@code atGeneration}.
+   * Classical usage is to {@code for (var e : this) if (e.isVisible(atGeneration) operation(e))}.
    */
-  public EnsoHashMapBuilder duplicatePartial(int numEntries) {
-    return new EnsoHashMapBuilder(this, numEntries);
-  }
-
-  /** Duplicates this builder with all its entries. */
-  @TruffleBoundary
-  public EnsoHashMapBuilder duplicate() {
-    return new EnsoHashMapBuilder(this);
-  }
-
-  /** Adds a key-value mapping, overriding any existing value. */
-  @TruffleBoundary(allowInlining = true)
-  public void add(Object key, Object value) {
-    var oldEntry = storage.get(key);
-    int newEntryIndex = oldEntry != null ? oldEntry.index : size;
-    var newEntry = new StorageEntry(key, value, newEntryIndex);
-    storage.put(key, newEntry);
-    if (oldEntry == null) {
-      assert newEntry.index == size;
-      sequentialEntries.add(newEntry);
-      size++;
-    } else {
-      sequentialEntries.set(newEntryIndex, newEntry);
-    }
-  }
-
-  @TruffleBoundary(allowInlining = true)
-  public StorageEntry get(Object key) {
-    return storage.get(key);
-  }
-
-  /**
-   * Removes an entry denoted by the given key.
-   *
-   * @return true if the removal was successful, i.e., the key was in the map and was removed, false
-   *     otherwise.
-   */
-  @TruffleBoundary
-  public boolean remove(Object key) {
-    var oldEntry = storage.removeKey(key);
-    if (oldEntry == null) {
-      return false;
-    } else {
-      sequentialEntries.remove(oldEntry.index);
-      // Rewrite rest of the sequentialEntries list and repair indexes in storage
-      for (int i = oldEntry.index; i < sequentialEntries.size(); i++) {
-        var entry = sequentialEntries.get(i);
-        StorageEntry newEntry = new StorageEntry(entry.key, entry.value, i);
-        sequentialEntries.set(i, newEntry);
-        storage.put(newEntry.key, newEntry);
+  public StorageEntry[] getEntries(int atGeneration, int size) {
+    var arr = new StorageEntry[size];
+    var at = 0;
+    for (var i = 0; i < byHash.length; i++) {
+      var e = byHash[i];
+      if (e != null && e.isVisible(atGeneration)) {
+        arr[at++] = e;
       }
-      size--;
-      return true;
+    }
+    if (at != arr.length) {
+      return Arrays.copyOf(arr, at);
+    } else {
+      return arr;
     }
   }
 
-  @TruffleBoundary(allowInlining = true)
-  public boolean containsKey(Object key) {
-    return storage.containsKey(key);
+  /**
+   * Prepares a builder ready for modification at given generation.
+   * It may return {@code this} if the {@code atGeneration == this.generation}
+   * and the {@code byHash} array is less than 75% full. Otherwise
+   * it may return new builder suitable for additions.
+   */
+  public EnsoHashMapBuilder asModifiable(int atGeneration, HashCodeNode hashCodeNode, EqualsNode equalsNode) {
+    if (atGeneration != generation || generation * 4 > byHash.length * 3) {
+      var newSize = Math.max(actualSize * 2, byHash.length);
+      return rehash(newSize, atGeneration, hashCodeNode, equalsNode);
+    } else {
+      return this;
+    }
   }
 
+  /** Adds a key-value mapping. Uses {@code hashCodeNode} to compute
+   * hash and based on it location in the array. Then it searches for
+   * first empty slot after the identified location. If it finds an
+   * equal key, it marks it as removed, if it hasn't been removed yet.
+   * Once it finds an empty slot, it puts there a new entry with
+   * the next generation.
+   */
+  public void put(
+    Object key, Object value,
+    HashCodeNode hashCodeNode, EqualsNode equalsNode
+  ) {
+    var at = findWhereToStart(key, hashCodeNode);
+    var nextGeneration = ++generation;
+    var replacingExistingKey = false;
+    for (var i = 0; i < byHash.length; i++) {
+      if (byHash[at] == null) {
+        if (!replacingExistingKey) {
+          actualSize++;
+        }
+        byHash[at] = new StorageEntry(key, value, nextGeneration);
+        return;
+      }
+      if (compare(equalsNode, byHash[at].key(), key)) {
+        var invalidatedEntry = byHash[at].markRemoved(nextGeneration);
+        if (invalidatedEntry != byHash[at]) {
+          byHash[at] = invalidatedEntry;
+          replacingExistingKey = true;
+        }
+      }
+      if (++at == byHash.length) {
+        at = 0;
+      }
+    }
+    throw CompilerDirectives.shouldNotReachHere("byHash array is full!");
+  }
+
+  /** Finds storage entry for given key or {@code null}.
+   * Searches only entries that are visible for given {@code generation}.
+   */
+  public StorageEntry get(
+    Object key, int generation,
+    HashCodeNode hashCodeNode, EqualsNode equalsNode
+  ) {
+    var at = findWhereToStart(key, hashCodeNode);
+    for (var i = 0; i < byHash.length; i++) {
+      if (byHash[at] == null) {
+        return null;
+      }
+      if (byHash[at].isVisible(generation)) {
+        if (compare(equalsNode, key, byHash[at].key())) {
+          return byHash[at];
+        }
+      }
+      if (++at == byHash.length) {
+        at = 0;
+      }
+    }
+    throw CompilerDirectives.shouldNotReachHere("byHash array is full!");
+  }
+
+  private int findWhereToStart(Object key, HashCodeNode hashCodeNode) {
+    var hash = Math.abs(hashCodeNode.execute(key));
+    var at = (int) (hash % byHash.length);
+    return at;
+  }
+
+  /**
+   * Removes an entry denoted by the given key. Removal is "non-destrutive" - the
+   * "removed" entry stays in the array - only its {@link StorageEntry#removed()}
+   * value is set to the next generation.
+   *
+   * @return true if the removal was successful false otherwise.
+   */
+  public boolean remove(
+    Object key,
+    HashCodeNode hashCodeNode, EqualsNode equalsNode
+  ) {
+    var at = findWhereToStart(key, hashCodeNode);
+    var nextGeneration = ++generation;
+    for (var i = 0; i < byHash.length; i++) {
+      if (byHash[at] == null) {
+        return false;
+      }
+      if (compare(equalsNode, key, byHash[at].key())) {
+        var invalidatedEntry = byHash[at].markRemoved(nextGeneration);
+        if (invalidatedEntry != byHash[at]) {
+          byHash[at] = invalidatedEntry;
+          actualSize--;
+          return true;
+        }
+      }
+      if (++at == byHash.length) {
+        at = 0;
+      }
+    }
+    throw CompilerDirectives.shouldNotReachHere("byHash array is full!");
+  }
+
+  /** Builds a new builder with given array size and puts into it all entries
+   * that are valid {@code atGeneration}.
+   */
+  private EnsoHashMapBuilder rehash(int size, int atGeneration, HashCodeNode hashCodeNode, EqualsNode equalsNode) {
+    var newBuilder = new EnsoHashMapBuilder(size);
+    for (var i = 0; i < byHash.length; i++) {
+      var entry = byHash[i];
+      if (entry != null && entry.isVisible(atGeneration)) {
+        newBuilder.put(entry.key(), entry.value(), hashCodeNode, equalsNode);
+      }
+    }
+    return newBuilder;
+  }
+
+
   /**
    * Creates a snapshot with the current size. The created snapshot contains all the entries that
    * are in the storage as of this moment, i.e., all the entries with their indexes lesser than
-   * {@code size}.
+   * {@code generation}.
    *
-   * <p>Should be called at most once for a particular {@code size}.
+   * <p>Should be called where most once for a particular {@code generation}.
    *
    * @return A new hash map snapshot.
    */
   public EnsoHashMap build() {
-    return EnsoHashMap.createWithBuilder(this, size);
+    return EnsoHashMap.createWithBuilder(this);
   }
 
   @Override
   public String toString() {
-    return "EnsoHashMapBuilder{size = " + size + ", storage = " + storage + "}";
+    return "EnsoHashMapBuilder{size = " + generation + ", storage = " + Arrays.toString(byHash) + "}";
+  }
+
+  private static boolean compare(EqualsNode equalsNode, Object a, Object b) {
+    if (a instanceof Double aDbl && b instanceof Double bDbl && aDbl.isNaN() && bDbl.isNaN()) {
+      return true;
+    } else {
+      return equalsNode.execute(a, b);
+    }
   }
 
   record StorageEntry(
-      Object key,
-      Object value,
-      /**
-       * A sequential index of the entry within this map. {@link EnsoHashMap} uses it for checking
-       * whether a certain key belongs in that map.
-       */
-      int index) {}
-
-  /**
-   * Custom {@link Equivalence} used for the {@link EconomicMap} that delegates {@code equals} to
-   * {@link EqualsNode} and {@code hash_code} to {@link HashCodeNode}.
-   */
-  private static final class StorageStrategy extends Equivalence {
-    private final EqualsNode equalsNode;
-    private final HashCodeNode hashCodeNode;
-
-    private StorageStrategy(EqualsNode equalsNode, HashCodeNode hashCodeNode) {
-      this.equalsNode = equalsNode;
-      this.hashCodeNode = hashCodeNode;
+    Object key,
+    Object value,
+    /**
+    * A generation the entry got into this map. {@link EnsoHashMap} uses it for checking
+    * whether a certain key belongs in that map.
+    */
+    int added,
+    /** Remove at a generation. */
+    int removed
+  ) {
+    StorageEntry(Object key, Object value, int added) {
+      this(key, value, added, Integer.MAX_VALUE);
     }
 
-    @Override
-    public boolean equals(Object a, Object b) {
-      // Special handling for NaN added as a key inside a map.
-      if (a instanceof Double aDbl && b instanceof Double bDbl && aDbl.isNaN() && bDbl.isNaN()) {
-        return true;
+    boolean isVisible(int generation) {
+      return added() <= generation && generation < removed();
+    }
+
+    StorageEntry markRemoved(int when) {
+      if (removed() <= when) {
+        return this;
       } else {
-        return Boolean.TRUE.equals(equalsNode.execute(a, b));
+        return new StorageEntry(key(), value(), added(), when);
       }
     }
-
-    @Override
-    public int hashCode(Object o) {
-      return (int) hashCodeNode.execute(o);
-    }
   }
 }

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapGetNode.java

@@ -11,10 +11,13 @@ import com.oracle.truffle.api.interop.UnknownKeyException;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
+
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode.TailStatus;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
+import org.enso.interpreter.runtime.data.text.Text;
+import org.enso.interpreter.runtime.error.PanicException;
 import org.enso.interpreter.runtime.state.State;
 
 @BuiltinMethod(
@@ -37,19 +40,18 @@ public abstract class HashMapGetNode extends Node {
 
   @Specialization(guards = "interop.hasHashEntries(self)", limit = "3")
   Object hashMapGet(
-      VirtualFrame frame,
-      State state, Object self, Object key, Object defaultValue,
-      @CachedLibrary("self") InteropLibrary interop,
-      @Shared @Cached("build()") ThunkExecutorNode thunkExecutorNode) {
-    if (interop.isHashEntryReadable(self, key)) {
+    VirtualFrame frame,
+    State state, Object self, Object key, Object defaultValue,
+    @CachedLibrary("self") InteropLibrary interop,
+    @Shared @Cached("build()") ThunkExecutorNode thunkExecutorNode
+  ) {
       try {
         return interop.readHashValue(self, key);
-      } catch (UnsupportedMessageException | UnknownKeyException e) {
-        throw new IllegalStateException(e);
+      } catch (UnknownKeyException e) {
+        return thunkExecutorNode.executeThunk(frame, defaultValue, state, TailStatus.NOT_TAIL);
+      } catch (UnsupportedMessageException e) {
+        throw new PanicException(Text.create(e.getMessage()), this);
       }
-    } else {
-      return thunkExecutorNode.executeThunk(frame, defaultValue, state, TailStatus.NOT_TAIL);
-    }
   }
 
   @Fallback

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapInsertNode.java

@@ -1,7 +1,14 @@
 package org.enso.interpreter.runtime.data.hash;
 
-import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
+import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.node.expression.builtin.meta.EqualsNode;
+import org.enso.interpreter.node.expression.builtin.meta.HashCodeNode;
+import org.enso.interpreter.runtime.data.text.Text;
+import org.enso.interpreter.runtime.error.PanicException;
+
+import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.dsl.Cached;
+import com.oracle.truffle.api.dsl.Cached.Shared;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.interop.InteropLibrary;
 import com.oracle.truffle.api.interop.InvalidArrayIndexException;
@@ -9,9 +16,6 @@ import com.oracle.truffle.api.interop.StopIterationException;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
-import org.enso.interpreter.dsl.BuiltinMethod;
-import org.enso.interpreter.node.expression.builtin.meta.EqualsNode;
-import org.enso.interpreter.node.expression.builtin.meta.HashCodeNode;
 
 @BuiltinMethod(
     type = "Map",
@@ -30,27 +34,15 @@ public abstract class HashMapInsertNode extends Node {
   public abstract EnsoHashMap execute(Object self, Object key, Object value);
 
   @Specialization
-  @TruffleBoundary
-  EnsoHashMap doEnsoHashMap(EnsoHashMap hashMap, Object key, Object value) {
-    EnsoHashMapBuilder mapBuilder = hashMap.getMapBuilder();
-    boolean containsKey = mapBuilder.get(key) != null;
-    boolean insertCalledOnMap = hashMap.isInsertCalled();
-    if (insertCalledOnMap || containsKey) {
-      // insert was already called on this map => We need to duplicate MapBuilder
-      // If a key is already contained in the Map there is no way telling whether there is another
-      // binding pointing to the Map, and we do not want to mutate this older binding.
-      var newMapBuilder = hashMap.getHashSize() < mapBuilder.getSize() ?
-          mapBuilder.duplicatePartial(hashMap.getHashSize()) :
-          mapBuilder.duplicate();
-      newMapBuilder.add(key, value);
-      return newMapBuilder.build();
-    } else {
-      // Do not duplicate the builder, just create a snapshot.
-      mapBuilder.add(key, value);
-      var newMap = mapBuilder.build();
-      hashMap.setInsertCalled();
-      return newMap;
-    }
+  EnsoHashMap doEnsoHashMap(
+    EnsoHashMap hashMap, Object key, Object value,
+    @Shared("hash") @Cached HashCodeNode hashCodeNode,
+    @Shared("equals") @Cached EqualsNode equalsNode
+  ) {
+    var mapBuilder = hashMap.getMapBuilder(false, hashCodeNode, equalsNode);
+    mapBuilder.put(key, value, hashCodeNode, equalsNode);
+    var newMap = mapBuilder.build();
+    return newMap;
   }
 
   /**
@@ -61,24 +53,25 @@ public abstract class HashMapInsertNode extends Node {
   EnsoHashMap doForeign(Object foreignMap, Object keyToInsert, Object valueToInsert,
       @CachedLibrary("foreignMap") InteropLibrary mapInterop,
       @CachedLibrary(limit = "3") InteropLibrary iteratorInterop,
-      @Cached HashCodeNode hashCodeNode,
-      @Cached EqualsNode equalsNode) {
-    var mapBuilder = EnsoHashMapBuilder.create(hashCodeNode, equalsNode);
+      @Shared("hash") @Cached HashCodeNode hashCodeNode,
+      @Shared("equals") @Cached EqualsNode equalsNode) {
+    var mapBuilder = EnsoHashMapBuilder.create();
     try {
       Object entriesIterator = mapInterop.getHashEntriesIterator(foreignMap);
       while (iteratorInterop.hasIteratorNextElement(entriesIterator)) {
         Object keyValueArr = iteratorInterop.getIteratorNextElement(entriesIterator);
         Object key = iteratorInterop.readArrayElement(keyValueArr, 0);
         Object value = iteratorInterop.readArrayElement(keyValueArr, 1);
-        mapBuilder.add(key, value);
+        mapBuilder = mapBuilder.asModifiable(mapBuilder.generation(), hashCodeNode, equalsNode);
+        mapBuilder.put(key, value, hashCodeNode, equalsNode);
       }
     } catch (UnsupportedMessageException | StopIterationException | InvalidArrayIndexException e) {
-      throw new IllegalStateException(
-          "Polyglot hash map " + foreignMap + " has wrongly specified Interop API (hash entries iterator)",
-          e
-      );
+      CompilerDirectives.transferToInterpreter();
+      var msg = "Polyglot hash map " + foreignMap + " has wrongly specified Interop API (hash entries iterator)";
+      throw new PanicException(Text.create(msg), this);
     }
-    mapBuilder.add(keyToInsert, valueToInsert);
-    return EnsoHashMap.createWithBuilder(mapBuilder, mapBuilder.getSize());
+    mapBuilder = mapBuilder.asModifiable(mapBuilder.generation(), hashCodeNode, equalsNode);
+    mapBuilder.put(keyToInsert, valueToInsert, hashCodeNode, equalsNode);
+    return EnsoHashMap.createWithBuilder(mapBuilder);
   }
 }

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapRemoveNode.java

@@ -1,7 +1,15 @@
 package org.enso.interpreter.runtime.data.hash;
 
+import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.node.expression.builtin.meta.EqualsNode;
+import org.enso.interpreter.node.expression.builtin.meta.HashCodeNode;
+import org.enso.interpreter.runtime.data.text.Text;
+import org.enso.interpreter.runtime.error.DataflowError;
+import org.enso.interpreter.runtime.error.PanicException;
+
 import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.dsl.Cached;
+import com.oracle.truffle.api.dsl.Cached.Shared;
 import com.oracle.truffle.api.dsl.GenerateUncached;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.interop.InteropLibrary;
@@ -10,10 +18,6 @@ import com.oracle.truffle.api.interop.StopIterationException;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
-import org.enso.interpreter.dsl.BuiltinMethod;
-import org.enso.interpreter.node.expression.builtin.meta.EqualsNode;
-import org.enso.interpreter.node.expression.builtin.meta.HashCodeNode;
-import org.enso.interpreter.runtime.error.DataflowError;
 
 @BuiltinMethod(
     type = "Map",
@@ -31,16 +35,16 @@ public abstract class HashMapRemoveNode extends Node {
   public abstract EnsoHashMap execute(Object self, Object key);
 
   @Specialization
-  EnsoHashMap removeFromEnsoMap(EnsoHashMap ensoMap, Object key) {
-    var oldEntry = ensoMap.getMapBuilder().get(key);
-    if (oldEntry == null) {
-      throw DataflowError.withoutTrace("No such key", null);
+  EnsoHashMap removeFromEnsoMap(
+    EnsoHashMap ensoMap, Object key,
+    @Shared("hash") @Cached HashCodeNode hashCodeNode,
+    @Shared("equals") @Cached EqualsNode equalsNode
+  ) {
+    var mapBuilder = ensoMap.getMapBuilder(false, hashCodeNode, equalsNode);
+    if (mapBuilder.remove(key, hashCodeNode, equalsNode)) {
+      return mapBuilder.build();
     } else {
-      var newBuilder = ensoMap.getMapBuilder().duplicate();
-      if (!newBuilder.remove(key)) {
-        throw new IllegalStateException("Key '" + key + "' should be in the map");
-      }
-      return EnsoHashMap.createWithBuilder(newBuilder, newBuilder.getSize());
+      throw DataflowError.withoutTrace("No such key", null);
     }
   }
 
@@ -49,13 +53,13 @@ public abstract class HashMapRemoveNode extends Node {
   )
   EnsoHashMap removeFromInteropMap(Object map, Object keyToRemove,
       @CachedLibrary(limit = "5") InteropLibrary interop,
-      @Cached HashCodeNode hashCodeNode,
-      @Cached EqualsNode equalsNode) {
+      @Shared("hash") @Cached HashCodeNode hashCodeNode,
+      @Shared("equals") @Cached EqualsNode equalsNode) {
     // We cannot simply call interop.isHashEntryExisting, because it would, most likely
     // use the default `hashCode` and `equals` Java methods. But we need to use our
     // EqualsNode, so we do the check for non-existing key inside the while loop.
     boolean keyToRemoveFound = false;
-    var mapBuilder = EnsoHashMapBuilder.create(hashCodeNode, equalsNode);
+    var mapBuilder = EnsoHashMapBuilder.create();
     try {
       Object entriesIterator = interop.getHashEntriesIterator(map);
       while (interop.hasIteratorNextElement(entriesIterator)) {
@@ -63,23 +67,24 @@ public abstract class HashMapRemoveNode extends Node {
         Object key = interop.readArrayElement(keyValueArr, 0);
         if ((boolean) equalsNode.execute(keyToRemove, key)) {
           if (keyToRemoveFound) {
-            throw new IllegalStateException("Key " + key + " found twice");
+            CompilerDirectives.transferToInterpreter();
+            throw new PanicException(Text.create("Key " + key + " found twice"), this);
           } else {
             keyToRemoveFound = true;
           }
         } else {
           Object value = interop.readArrayElement(keyValueArr, 1);
-          mapBuilder.add(key, value);
+          mapBuilder = mapBuilder.asModifiable(mapBuilder.generation(), hashCodeNode, equalsNode);
+          mapBuilder.put(key, value, hashCodeNode, equalsNode);
         }
       }
     } catch (UnsupportedMessageException | StopIterationException | InvalidArrayIndexException e) {
-      throw new IllegalStateException(
-          "Polyglot hash map " + map + " has wrongly specified Interop API (hash entries iterator)",
-          e
-      );
+      CompilerDirectives.transferToInterpreter();
+      var msg = "Polyglot hash map " + map + " has wrongly specified Interop API (hash entries iterator)";
+      throw new PanicException(Text.create(msg), this);
     }
     if (keyToRemoveFound) {
-      return EnsoHashMap.createWithBuilder(mapBuilder, mapBuilder.getSize());
+      return EnsoHashMap.createWithBuilder(mapBuilder);
     } else {
       CompilerDirectives.transferToInterpreter();
       throw DataflowError.withoutTrace("No such key " + keyToRemove, interop);

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapSizeNode.java

@@ -8,6 +8,8 @@ import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.runtime.data.text.Text;
+import org.enso.interpreter.runtime.error.PanicException;
 
 @BuiltinMethod(
     type = "Map",
@@ -28,7 +30,7 @@ public abstract class HashMapSizeNode extends Node {
     try {
       return interop.getHashSize(hashMap);
     } catch (UnsupportedMessageException e) {
-      throw new IllegalStateException(e);
+      throw new PanicException(Text.create(e.getMessage()), this);
     }
   }
 

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapToTextNode.java

@@ -8,7 +8,12 @@ import com.oracle.truffle.api.interop.StopIterationException;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
+
 import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.runtime.data.text.Text;
+import org.enso.interpreter.runtime.error.PanicException;
+
+import com.oracle.truffle.api.CompilerDirectives;
 
 @BuiltinMethod(
     type = "Map",
@@ -45,10 +50,9 @@ public abstract class HashMapToTextNode extends Node {
         sb.delete(sb.length() - 2, sb.length());
       }
     } catch (UnsupportedMessageException | StopIterationException | InvalidArrayIndexException e) {
-      throw new IllegalStateException(
-          "hashMap " + hashMap + " probably implements interop API incorrectly",
-          e
-      );
+      CompilerDirectives.transferToInterpreter();
+      var msg = "hashMap " + hashMap + " probably implements interop API incorrectly";
+      throw new PanicException(Text.create(msg), this);
     }
     sb.append("}");
     return sb.toString();

engine/runtime/src/main/java/org/enso/interpreter/runtime/data/hash/HashMapToVectorNode.java

@@ -1,8 +1,11 @@
 package org.enso.interpreter.runtime.data.hash;
 
 import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.runtime.data.text.Text;
 import org.enso.interpreter.runtime.data.vector.ArrayLikeHelpers;
+import org.enso.interpreter.runtime.error.PanicException;
 
+import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.dsl.Cached;
 import com.oracle.truffle.api.dsl.Fallback;
 import com.oracle.truffle.api.dsl.GenerateUncached;
@@ -71,7 +74,9 @@ public abstract class HashMapToVectorNode extends Node {
           HashEntriesVector.createFromKeysAndValues(keys, values)
       );
     } catch (UnsupportedMessageException | StopIterationException | InvalidArrayIndexException e) {
-      throw new IllegalStateException("hashMap: " + hashMap + " has probably wrong hash interop API", e);
+      CompilerDirectives.transferToInterpreter();
+      var msg = "hashMap: " + hashMap + " has probably wrong hash interop API";
+      throw new PanicException(Text.create(msg), mapInterop);
     }
   }
 

test/Table_Tests/src/Common_Table_Operations/Select_Columns_Spec.enso

@@ -425,7 +425,7 @@ spec setup =
             t2.should_fail_with Ambiguous_Column_Rename
             err = t2.catch
             err.column_name . should_equal "alpha"
-            err.new_names . should_equal ["StartsWithA", "EndsWithA"]
+            err.new_names . sort . should_equal ["EndsWithA", "StartsWithA"]
 
             t3 = table_builder [["aaa", [1]], ["bbb", [2]]]
             ## The rename patterns are deliberately prepared so that both will
@@ -459,7 +459,7 @@ spec setup =
         Test.specify "should correctly handle problems: duplicate names" <|
             map = ["Test", "Test", "Test", "Test"]
             action = table.rename_columns map on_problems=_
-            tester = expect_column_names ["Test", "Test 1", "Test 2", "Test 3"]
+            tester = expect_column_names ["Test 1", "Test 2", "Test 3", "Test"]
             problems = [Duplicate_Output_Column_Names.Error ["Test", "Test", "Test"]]
             Problems.test_problem_handling action problems tester
 

test/Tests/src/Data/Map_Spec.enso

@@ -264,7 +264,7 @@ spec =
 
         Test.specify "should convert the whole map to a vector" <|
             m = Map.empty . insert 0 0 . insert 3 -5 . insert 1 2
-            m.to_vector.should_equal [[0, 0], [3, -5], [1, 2]]
+            m.to_vector.sort on=_.first . should_equal [[0, 0], [1, 2], [3, -5]]
 
         Test.specify "should allow building the map from two vectors" <|
             expected = Map.empty . insert 0 0 . insert 3 -5 . insert 1 2
@@ -300,7 +300,9 @@ spec =
 
         Test.specify "should define a well-defined text conversion" <|
             m = Map.empty . insert 0 0 . insert 3 -5 . insert 1 2
-            m.to_text . should_equal "{0=0, 3=-5, 1=2}"
+            m.to_text . should_contain "0=0"
+            m.to_text . should_contain "3=-5"
+            m.to_text . should_contain "1=2"
 
         Test.specify "should define structural equality" <|
             map_1 = Map.empty . insert "1" 2 . insert "2" "1"
@@ -564,7 +566,7 @@ spec =
             js_dict = js_dict_from_vec ["A", 1, "B", 2]
             map = js_dict.insert "C" 3
             js_dict.to_vector.should_equal [["A", 1], ["B", 2]]
-            map.to_vector.should_equal [["A", 1], ["B", 2], ["C", 3]]
+            map.to_vector.sort on=_.first . should_equal [["A", 1], ["B", 2], ["C", 3]]
 
         Test.specify "should treat Java Map as Enso map" <|
             sort_by_keys vec = vec.sort by=x-> y-> Ordering.compare x.first y.first

test/Visualization_Tests/src/Scatter_Plot_Spec.enso

@@ -107,7 +107,7 @@ spec =
             data = json.get 'data'
             data.should_be_a Vector
             data.length . should_equal 10
-            (data.take (First 3)).to_text . should_equal '[{"x":0,"y":225}, {"x":29,"y":196}, {"x":15,"y":0}]'
+            (data.take (First 3) . sort on=(_.get "x")).to_text . should_equal '[{"x":0,"y":225}, {"x":15,"y":0}, {"x":29,"y":196}]'
 
         Test.specify "filter the elements" <|
             vector = [0,10,20,30]