frontend: Add alias resource type splitting (#510)

* frontend: Add alias resource type splitting

* frontend: Improve alias resource type splitting

* frontend: Fixing write value

---------

Co-authored-by: Johannes Zottele <official@johannes-zottele.at>

Author: flofriday

vadl/main/vadl/ast/BehaviorLowering.java

@@ -245,15 +245,20 @@ private ExpressionNode buildConstraintDontMatchCheck(List<ExpressionNode> indice
         : or(constChecks);
   }
 
+  /**
+   * The function returned represents how the read from the acutal resource will be transformed
+   * to the value the alias read actually returns.
+   *
+   * @param definition of the alias definition for which the read function will be generated.
+   * @return the mapping function.
+   */
   Function getRegisterAliasReadFunc(AliasDefinition definition) {
     var graph = new Graph("%s Read Behavior".formatted(definition.viamId));
     graph.setSourceLocation(definition.location());
     currentGraph = graph;
 
     final var identifier =
         viamLowering.generateIdentifier(definition.viamId + "::read", definition.loc);
-    final var regFileDef = (RegisterDefinition) Objects.requireNonNull(definition.computedTarget);
-    final var zeroConst = definition.getAnnotation("zero", ZeroConstraintAnnotation.class);
 
     DataType resultType;
     // Initially the indices are all fixed arguments specified in the alias definition.
@@ -275,21 +280,23 @@ Function getRegisterAliasReadFunc(AliasDefinition definition) {
           0);
       params.add(param);
       indices.add(new FuncParamNode(param));
-      resultType = relType.resultType().asDataType();
+      resultType = getViamType(relType.resultType()).asDataType();
     } else {
-      resultType = definition.type().asDataType();
+      resultType = getViamType(definition.type()).asDataType();
     }
 
+    final var regFileDef = (RegisterDefinition) Objects.requireNonNull(definition.computedTarget);
     var reg = (RegisterTensor) viamLowering.fetch(regFileDef).orElseThrow();
     var regReadType = regFileDef.type() instanceof ConcreteRelationType relType
-        ? relType.resultType().asDataType() : resultType.asDataType();
+        ? relType.resultType().asDataType() : resultType;
     ExpressionNode regAccess = new ReadRegTensorNode(
         reg,
         indices,
         regReadType,
         null
     );
 
+    final var zeroConst = definition.getAnnotation("zero", ZeroConstraintAnnotation.class);
     if (zeroConst != null) {
       // Wrap the register read in a conditional read, depending on the indices values.
       // Compatibility was already checked by the annotation itself during type checking.
@@ -314,7 +321,7 @@ Function getRegisterAliasReadFunc(AliasDefinition definition) {
     return new Function(
         identifier,
         params.toArray(vadl.viam.Parameter[]::new),
-        getViamType(resultType),
+        resultType,
         graph
     );
   }
@@ -349,16 +356,16 @@ Procedure getRegisterAliasWriteProc(AliasDefinition definition) {
           0);
       params.add(param);
       indices.add(new FuncParamNode(param));
-      resultType = relType.resultType().asDataType();
+      resultType = getViamType(relType.resultType()).asDataType();
     } else {
-      resultType = definition.type().asDataType();
+      resultType = getViamType(definition.type()).asDataType();
     }
 
     var valueParam = new vadl.viam.Parameter(
         viamLowering.generateIdentifier(
             identifier.name() + "::value",
             identifier.location()),
-        getViamType(resultType),
+        resultType,
         1);
     params.add(valueParam);
 
@@ -1167,7 +1174,7 @@ private ExpressionNode sliceWriteValue(ExpressionNode value,
       consumed += part.size();
     }
 
-    var mask = slice.mask().castTo(Type.bits(entireRead.type().bitWidth())).toNode();
+    var mask = slice.mask().castTo(Type.bits(entireRead.type().bitWidth())).not().toNode();
     var clearedResource = BuiltInCall.of(BuiltInTable.AND, entireRead, mask);
     return BuiltInCall.of(BuiltInTable.OR, clearedResource, Objects.requireNonNull(injected));
   }

vadl/main/vadl/ast/Expr.java

@@ -1405,6 +1405,15 @@ public TypeLiteral(Type type, SourceLocation loc) {
       this.baseType = new Identifier(formatType.format.identifier().name,
           SourceLocation.INVALID_SOURCE_LOCATION);
       this.sizeIndices = List.of();
+    } else if (type instanceof TensorType tensortype) {
+      var innerLiteral = new TypeLiteral(tensortype.innerType(), loc);
+      this.baseType = innerLiteral.baseType;
+      var indices = new ArrayList<Expr>();
+      for (var i : tensortype.indexDims()) {
+        indices.add(new IntegerLiteral(Integer.toString(i), loc));
+      }
+      indices.addAll(innerLiteral.sizeIndices);
+      this.sizeIndices = indices;
     } else {
       throw new IllegalStateException("Unsupported type " + type.getClass().getSimpleName());
     }

vadl/main/vadl/ast/TypeChecker.java

@@ -1008,8 +1008,21 @@ public Void visit(AliasDefinition definition) {
 
       var valType = definition.value.type();
       if (definition.aliasType != null) {
-        definition.type = check(definition.aliasType);
-        definition.value = tryWrapImplicitCast(definition.value, definition.type);
+        var aliasType = check(definition.aliasType);
+        definition.type = aliasType;
+
+        // We have special casting rules here.
+        // They aren't as strict as implicit casting and not as lax as explicit casting.
+        // FIXME: Should we allow same rules as explicit casts here?
+        if (canImplicitCast(valType, aliasType)) {
+          definition.value = tryWrapImplicitCast(definition.value, definition.type);
+        } else if (aliasType instanceof DataType aliasDataType
+            && valType instanceof DataType valDataType
+            && aliasDataType.bitWidth() == valDataType.bitWidth()) {
+          definition.value = new CastExpr(definition.value, aliasType);
+        } else {
+          throw typeMismatchError(definition.value, aliasType, valType);
+        }
       } else {
         definition.type = valType;
       }