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/* * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.oracle.truffle.dsl.processor.expression; import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Objects; import java.util.Set; import javax.lang.model.element.ElementKind; import javax.lang.model.element.ExecutableElement; import javax.lang.model.element.VariableElement; import javax.lang.model.type.TypeMirror; import org.antlr.v4.runtime.BaseErrorListener; import org.antlr.v4.runtime.CharStreams; import org.antlr.v4.runtime.CommonTokenStream; import org.antlr.v4.runtime.RecognitionException; import org.antlr.v4.runtime.Recognizer; import org.antlr.v4.runtime.TokenStream; import com.oracle.truffle.dsl.processor.generator.DSLExpressionGenerator; import com.oracle.truffle.dsl.processor.java.model.CodeTree; public abstract class DSLExpression { private TypeMirror resolvedTargetType; private DSLExpression() { } private static final class DSLErrorListener extends BaseErrorListener { static DSLErrorListener INSTANCE = new DSLErrorListener(); @Override public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line, int charPositionInLine, String msg, RecognitionException e) { throw new InvalidExpressionException("line " + line + ":" + charPositionInLine + " " + msg); } } public static DSLExpression parse(String input) { ExpressionLexer lexer = new ExpressionLexer(CharStreams.fromString(input)); TokenStream tokens = new CommonTokenStream(lexer); ExpressionParser parser = new ExpressionParser(tokens); lexer.removeErrorListeners(); parser.removeErrorListeners(); lexer.addErrorListener(DSLErrorListener.INSTANCE); parser.addErrorListener(DSLErrorListener.INSTANCE); try { return parser.expression().result; } catch (RecognitionException e) { throw new InvalidExpressionException(e.getMessage()); } } public final Set<VariableElement> findBoundVariableElements() { final Set<VariableElement> variables = new HashSet<>(); this.accept(new AbstractDSLExpressionVisitor() { @Override public void visitVariable(Variable variable) { if (variable.getReceiver() == null) { variables.add(variable.getResolvedVariable()); } } }); return variables; } public final Set<Variable> findBoundVariables() { final Set<Variable> variables = new HashSet<>(); this.accept(new AbstractDSLExpressionVisitor() { @Override public void visitVariable(Variable variable) { if (variable.getReceiver() == null) { variables.add(variable); } } }); return variables; } public Object resolveConstant() { return null; } public void setResolvedTargetType(TypeMirror resolvedTargetType) { this.resolvedTargetType = resolvedTargetType; } public TypeMirror getResolvedTargetType() { return resolvedTargetType; } public String asString() { CodeTree tree = DSLExpressionGenerator.write(this, null, new HashMap<>()); return tree.toString(); } public abstract TypeMirror getResolvedType(); public abstract void accept(DSLExpressionVisitor visitor); public abstract DSLExpression reduce(DSLExpressionReducer visitor); private DSLExpression reduceImpl(DSLExpressionReducer reducer) { DSLExpression expression = reduce(reducer); if (expression == null) { return this; } return expression; } public static final class Negate extends DSLExpression { private final DSLExpression receiver; public Negate(DSLExpression receiver) { this.receiver = receiver; } @Override public void accept(DSLExpressionVisitor visitor) { receiver.accept(visitor); visitor.visitNegate(this); } @Override public DSLExpression reduce(DSLExpressionReducer visitor) { DSLExpression newReceiver = receiver.reduceImpl(visitor); DSLExpression negate = this; if (newReceiver != receiver) { negate = new Negate(newReceiver); negate.setResolvedTargetType(getResolvedTargetType()); } return negate; } public DSLExpression getReceiver() { return receiver; } @Override public Object resolveConstant() { Object constant = receiver.resolveConstant(); if (constant instanceof Integer) { return -(int) constant; } return super.resolveConstant(); } @Override public TypeMirror getResolvedType() { return receiver.getResolvedType(); } @Override public boolean equals(Object obj) { if (obj instanceof Negate) { return receiver.equals(((Negate) obj).receiver); } return false; } @Override public int hashCode() { return receiver.hashCode(); } } public static final class Binary extends DSLExpression { private final String operator; private final DSLExpression left; private final DSLExpression right; private TypeMirror resolvedType; public Binary(String operator, DSLExpression left, DSLExpression right) { this.operator = operator; this.left = left; this.right = right; } public boolean isComparison() { return DSLExpressionResolver.COMPARABLE_OPERATORS.contains(operator) || DSLExpressionResolver.IDENTITY_OPERATORS.contains(operator); } @Override public boolean equals(Object obj) { if (obj instanceof Binary) { Binary other = (Binary) obj; return operator.equals(other.operator) && left.equals(other.left) && right.equals(other.right); } return false; } @Override public int hashCode() { return Objects.hash(operator, left, right); } public String getOperator() { return operator; } public DSLExpression getLeft() { return left; } public DSLExpression getRight() { return right; } @Override public void accept(DSLExpressionVisitor visitor) { left.accept(visitor); right.accept(visitor); visitor.visitBinary(this); } @Override public DSLExpression reduce(DSLExpressionReducer reducer) { DSLExpression newLeft = left.reduceImpl(reducer); DSLExpression newRight = right.reduceImpl(reducer); Binary b = this; if (newLeft != left || newRight != right) { b = new Binary(getOperator(), newLeft, newRight); b.setResolvedTargetType(getResolvedTargetType()); b.setResolvedType(getResolvedType()); } return reducer.visitBinary(b); } @Override public TypeMirror getResolvedType() { return resolvedType; } public void setResolvedType(TypeMirror resolvedType) { this.resolvedType = resolvedType; } @Override public String toString() { return "Binary [left=" + left + ", operator=" + operator + ", right=" + right + ", resolvedType=" + resolvedType + "]"; } } public static final class Call extends DSLExpression { private final DSLExpression receiver; private final String name; private final List<DSLExpression> parameters; private ExecutableElement resolvedMethod; public Call(DSLExpression receiver, String name, List<DSLExpression> parameters) { this.receiver = receiver; this.name = name; this.parameters = parameters; } @Override public boolean equals(Object obj) { if (obj instanceof Call) { Call other = (Call) obj; return Objects.equals(receiver, other.receiver) && name.equals(other.name) && parameters.equals(other.parameters); } return false; } @Override public int hashCode() { return Objects.hash(receiver, name, parameters); } public DSLExpression getReceiver() { return receiver; } public String getName() { return name; } public List<DSLExpression> getParameters() { return parameters; } @Override public void accept(DSLExpressionVisitor visitor) { if (receiver != null) { receiver.accept(visitor); } for (DSLExpression parameter : getParameters()) { parameter.accept(visitor); } visitor.visitCall(this); } @Override public DSLExpression reduce(DSLExpressionReducer reducer) { DSLExpression newReceiver = null; if (receiver != null) { newReceiver = receiver.reduceImpl(reducer); } boolean parameterChanged = false; List<DSLExpression> newParameters = new ArrayList<>(); for (DSLExpression param : getParameters()) { DSLExpression newParam = param.reduceImpl(reducer); if (newParam != param) { parameterChanged = true; newParameters.add(newParam); } else { newParameters.add(param); } } Call c = this; if (newReceiver != receiver || parameterChanged) { c = new Call(newReceiver, getName(), newParameters); c.setResolvedMethod(getResolvedMethod()); c.setResolvedTargetType(getResolvedTargetType()); } return reducer.visitCall(c); } @Override public TypeMirror getResolvedType() { if (resolvedMethod == null) { return null; } if (resolvedMethod.getKind() == ElementKind.CONSTRUCTOR) { return resolvedMethod.getEnclosingElement().asType(); } else { return resolvedMethod.getReturnType(); } } public ExecutableElement getResolvedMethod() { return resolvedMethod; } public void setResolvedMethod(ExecutableElement resolvedMethod) { this.resolvedMethod = resolvedMethod; } @Override public String toString() { return "Call [receiver=" + receiver + ", name=" + name + ", parameters=" + parameters + ", resolvedMethod=" + resolvedMethod + "]"; } } public static final class Variable extends DSLExpression { private final DSLExpression receiver; private final String name; private VariableElement resolvedVariable; public Variable(DSLExpression receiver, String name) { this.receiver = receiver; this.name = name; } @Override public boolean equals(Object obj) { if (obj instanceof Variable) { Variable other = (Variable) obj; return Objects.equals(receiver, other.receiver) && name.equals(other.name); } return false; } @Override public int hashCode() { return Objects.hash(receiver, name); } public DSLExpression getReceiver() { return receiver; } public String getName() { return name; } @Override public void accept(DSLExpressionVisitor visitor) { if (receiver != null) { receiver.accept(visitor); } visitor.visitVariable(this); } @Override public DSLExpression reduce(DSLExpressionReducer reducer) { DSLExpression newReceiver = null; if (receiver != null) { newReceiver = receiver.reduceImpl(reducer); } Variable c = this; if (newReceiver != receiver) { c = new Variable(newReceiver, getName()); c.setResolvedTargetType(getResolvedTargetType()); c.setResolvedVariable(getResolvedVariable()); } return reducer.visitVariable(c); } @Override public TypeMirror getResolvedType() { return resolvedVariable != null ? resolvedVariable.asType() : null; } public void setResolvedVariable(VariableElement resolvedVariable) { this.resolvedVariable = resolvedVariable; } public VariableElement getResolvedVariable() { return resolvedVariable; } @Override public String toString() { return "Variable [receiver=" + receiver + ", name=" + name + ", resolvedVariable=" + resolvedVariable + "]"; } } public static final class IntLiteral extends DSLExpression { private final String literal; private int resolvedValueInt; private TypeMirror resolvedType; public IntLiteral(String literal) { this.literal = literal; } @Override public boolean equals(Object obj) { if (obj instanceof IntLiteral) { IntLiteral other = (IntLiteral) obj; return resolvedValueInt == other.resolvedValueInt; } return false; } @Override public Object resolveConstant() { return resolvedValueInt; } @Override public int hashCode() { return resolvedValueInt; } public String getLiteral() { return literal; } public int getResolvedValueInt() { return resolvedValueInt; } public void setResolvedValueInt(int resolved) { this.resolvedValueInt = resolved; } @Override public TypeMirror getResolvedType() { return resolvedType; } public void setResolvedType(TypeMirror resolvedType) { this.resolvedType = resolvedType; } @Override public void accept(DSLExpressionVisitor visitor) { visitor.visitIntLiteral(this); } @Override public DSLExpression reduce(DSLExpressionReducer reducer) { return this; } @Override public String toString() { return "IntLiteral [literal=" + literal + ", resolvedValueInt=" + resolvedValueInt + ", resolvedType=" + resolvedType + "]"; } } public static final class BooleanLiteral extends DSLExpression { private final boolean literal; private TypeMirror resolvedType; public BooleanLiteral(boolean literal) { this.literal = literal; } @Override public boolean equals(Object obj) { if (obj instanceof BooleanLiteral) { BooleanLiteral other = (BooleanLiteral) obj; return literal == other.literal; } return false; } @Override public Object resolveConstant() { return literal; } @Override public int hashCode() { return Boolean.hashCode(literal); } public boolean getLiteral() { return literal; } @Override public TypeMirror getResolvedType() { return resolvedType; } public void setResolvedType(TypeMirror resolvedType) { this.resolvedType = resolvedType; } @Override public void accept(DSLExpressionVisitor visitor) { visitor.visitBooleanLiteral(this); } @Override public DSLExpression reduce(DSLExpressionReducer reducer) { return this; } @Override public String toString() { return "BooleanLiteral [literal=" + literal + ", resolvedType=" + resolvedType + "]"; } } public abstract class AbstractDSLExpressionVisitor implements DSLExpressionVisitor { @Override public void visitBinary(Binary binary) { } @Override public void visitCall(Call binary) { } @Override public void visitIntLiteral(IntLiteral binary) { } @Override public void visitNegate(Negate negate) { } @Override public void visitVariable(Variable binary) { } public void visitBooleanLiteral(BooleanLiteral binary) { } } public interface DSLExpressionVisitor { void visitBinary(Binary binary); void visitNegate(Negate negate); void visitCall(Call binary); void visitVariable(Variable binary); void visitIntLiteral(IntLiteral binary); void visitBooleanLiteral(BooleanLiteral binary); } public abstract static class AbstractDSLExpressionReducer implements DSLExpressionReducer { @Override public DSLExpression visitBinary(Binary binary) { return binary; } @Override public DSLExpression visitCall(Call binary) { return binary; } @Override public DSLExpression visitNegate(Negate negate) { return negate; } @Override public DSLExpression visitVariable(Variable binary) { return binary; } } public interface DSLExpressionReducer { DSLExpression visitBinary(Binary binary); DSLExpression visitNegate(Negate negate); DSLExpression visitCall(Call binary); DSLExpression visitVariable(Variable binary); } }