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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.
*
* 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.
*
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package com.oracle.truffle.dsl.processor.generator;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Map;
import javax.lang.model.element.Element;
import javax.lang.model.element.ElementKind;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.Modifier;
import javax.lang.model.element.VariableElement;
import javax.lang.model.type.TypeKind;
import com.oracle.truffle.dsl.processor.expression.DSLExpression;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.Binary;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.BooleanLiteral;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.Call;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.DSLExpressionVisitor;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.IntLiteral;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.Negate;
import com.oracle.truffle.dsl.processor.expression.DSLExpression.Variable;
import com.oracle.truffle.dsl.processor.java.model.CodeTree;
import com.oracle.truffle.dsl.processor.java.model.CodeTreeBuilder;
public class DSLExpressionGenerator implements DSLExpressionVisitor {
private final Map<Variable, CodeTree> bindings;
private final CodeTree root;
private final Deque<CodeTree> stack = new ArrayDeque<>();
public DSLExpressionGenerator(CodeTree root, Map<Variable, CodeTree> bindings) {
this.bindings = bindings;
this.root = root;
}
public void visitBinary(Binary binary) {
CodeTree right = stack.pop();
CodeTree left = stack.pop();
stack.push(combine(left, string(" " + binary.getOperator() + " "), right));
}
public void visitCall(Call call) {
ExecutableElement method = call.getResolvedMethod();
CodeTree[] parameters = new CodeTree[method.getParameters().size()];
for (int i = 0; i < parameters.length; i++) {
parameters[parameters.length - i - 1] = pop();
}
CodeTreeBuilder builder = CodeTreeBuilder.createBuilder();
if (call.getResolvedMethod().getKind() == ElementKind.CONSTRUCTOR) {
builder.startNew(call.getResolvedType());
} else if (call.getReceiver() == null) {
if (isStatic(method)) {
builder.startStaticCall(method);
} else {
if (root != null) {
builder.tree(root).string(".");
}
builder.startCall(method.getSimpleName().toString());
}
} else {
if (isStatic(method)) {
throw new AssertionError("Static calls must not have receivers.");
}
builder.startCall(pop(), method.getSimpleName().toString());
}
for (CodeTree parameter : parameters) {
builder.tree(parameter);
}
builder.end();
push(builder.build());
}
public void visitIntLiteral(IntLiteral binary) {
push(string(binary.getLiteral()));
}
public void visitBooleanLiteral(BooleanLiteral binary) {
push(string(binary.getLiteral() ? "true" : "false"));
}
public void visitNegate(Negate negate) {
push(combine(string("!"), combine(string("("), pop(), string(")"))));
}
public void visitVariable(Variable variable) {
VariableElement resolvedVariable = variable.getResolvedVariable();
CodeTree tree;
if (variable.getResolvedType().getKind() == TypeKind.NULL) {
tree = CodeTreeBuilder.singleString("null");
} else if (variable.getReceiver() == null) {
if (isStatic(resolvedVariable)) {
tree = staticReference(resolvedVariable);
} else {
tree = bindings.get(variable);
boolean bound = true;
if (tree == null) {
tree = string(resolvedVariable.getSimpleName().toString());
bound = false;
}
if (root != null && !bound) {
tree = combine(root, string("."), tree);
}
}
} else {
if (isStatic(resolvedVariable)) {
throw new AssertionError("Static variables cannot have receivers.");
}
tree = combine(pop(), string("."), string(resolvedVariable.getSimpleName().toString()));
}
push(tree);
}
private static boolean isStatic(Element element) {
return element.getModifiers().contains(Modifier.STATIC);
}
private static CodeTree combine(CodeTree tree1, CodeTree tree2) {
return new CodeTreeBuilder(null).startGroup().tree(tree1).tree(tree2).end().build();
}
private static CodeTree combine(CodeTree tree1, CodeTree tree2, CodeTree tree3) {
return new CodeTreeBuilder(null).startGroup().tree(tree1).tree(tree2).tree(tree3).end().build();
}
private static CodeTree string(String s) {
return CodeTreeBuilder.singleString(s);
}
private static CodeTree staticReference(VariableElement var) {
return CodeTreeBuilder.createBuilder().staticReference(var.getEnclosingElement().asType(), var.getSimpleName().toString()).build();
}
private void push(CodeTree tree) {
stack.push(tree);
}
private CodeTree pop() {
return stack.pop();
}
public static CodeTree write(DSLExpression expression, CodeTree root, Map<Variable, CodeTree> bindings) {
DSLExpressionGenerator writer = new DSLExpressionGenerator(root, bindings);
expression.accept(writer);
return combine(string("("), writer.pop(), string(")"));
}
}