| /* |
| * Copyright 2008 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| * use this file except in compliance with the License. You may obtain a copy of |
| * the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package com.google.gwt.dev.jjs.impl; |
| |
| import com.google.gwt.dev.jjs.SourceInfo; |
| import com.google.gwt.dev.jjs.ast.Context; |
| import com.google.gwt.dev.jjs.ast.JArrayRef; |
| import com.google.gwt.dev.jjs.ast.JArrayType; |
| import com.google.gwt.dev.jjs.ast.JBinaryOperation; |
| import com.google.gwt.dev.jjs.ast.JBinaryOperator; |
| import com.google.gwt.dev.jjs.ast.JCastOperation; |
| import com.google.gwt.dev.jjs.ast.JCharLiteral; |
| import com.google.gwt.dev.jjs.ast.JClassType; |
| import com.google.gwt.dev.jjs.ast.JExpression; |
| import com.google.gwt.dev.jjs.ast.JInstanceOf; |
| import com.google.gwt.dev.jjs.ast.JIntLiteral; |
| import com.google.gwt.dev.jjs.ast.JMethod; |
| import com.google.gwt.dev.jjs.ast.JMethodCall; |
| import com.google.gwt.dev.jjs.ast.JModVisitor; |
| import com.google.gwt.dev.jjs.ast.JNullLiteral; |
| import com.google.gwt.dev.jjs.ast.JNullType; |
| import com.google.gwt.dev.jjs.ast.JPrimitiveType; |
| import com.google.gwt.dev.jjs.ast.JProgram; |
| import com.google.gwt.dev.jjs.ast.JReferenceType; |
| import com.google.gwt.dev.jjs.ast.JType; |
| import com.google.gwt.dev.jjs.ast.JTypeOracle; |
| import com.google.gwt.dev.jjs.ast.JVisitor; |
| import com.google.gwt.dev.jjs.ast.js.JsonObject; |
| import com.google.gwt.dev.jjs.ast.js.JsonObject.JsonPropInit; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.IdentityHashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * Replace cast and instanceof operations with calls to the Cast class. Depends |
| * on {@link CatchBlockNormalizer}, {@link CompoundAssignmentNormalizer}, |
| * {@link JsoDevirtualizer}, and {@link LongCastNormalizer} having already run. |
| * |
| * <p> |
| * Object and String always get a queryId of 0 and 1, respectively. The 0 |
| * queryId always means "always succeeds". In practice, we never generate an |
| * explicit cast with a queryId of 0; it is only used for array store checking, |
| * where the 0 queryId means that anything can be stored into an Object[]. |
| * </p> |
| * <p> |
| * JavaScriptObject has a queryId of -1, which again is only used for array store |
| * checking, to ensure that a non-JSO is not stored into a JavaScriptObject[]. |
| * </p> |
| */ |
| public class CastNormalizer { |
| private class AssignTypeCastabilityVisitor extends JVisitor { |
| |
| Set<JReferenceType> alreadyRan = new HashSet<JReferenceType>(); |
| private IdentityHashMap<JReferenceType, JsonObject> |
| castableTypeMaps = new IdentityHashMap<JReferenceType, JsonObject>(); |
| private final List<JArrayType> instantiatedArrayTypes = |
| new ArrayList<JArrayType>(); |
| private int nextQueryId = 0; |
| private Map<JReferenceType, Set<JReferenceType>> queriedTypes = |
| new IdentityHashMap<JReferenceType, Set<JReferenceType>>(); |
| |
| { |
| JTypeOracle typeOracle = program.typeOracle; |
| for (JArrayType arrayType : program.getAllArrayTypes()) { |
| if (typeOracle.isInstantiatedType(arrayType)) { |
| instantiatedArrayTypes.add(arrayType); |
| } |
| } |
| |
| // Reserve query id 0 for java.lang.Object (for array stores on JSOs). |
| recordCastInternal(program.getTypeJavaLangObject(), |
| program.getTypeJavaLangObject()); |
| |
| // Reserve query id 1 for java.lang.String to facilitate the mashup case. |
| // Also, facilitates detecting an object as a Java String (see Cast.java) |
| // Multiple GWT modules need to modify String's prototype the same way. |
| recordCastInternal(program.getTypeJavaLangString(), |
| program.getTypeJavaLangObject()); |
| } |
| |
| public void computeTypeCastabilityMaps() { |
| |
| // do String first (which will pull in Object also, it's superclass). |
| computeSourceType(program.getTypeJavaLangString()); |
| assert (castableTypeMaps.size() == 2); |
| |
| /* |
| * Compute the list of classes than can successfully satisfy cast |
| * requests, along with the set of types they can be successfully cast to. |
| * Do it in super type order. |
| */ |
| for (JReferenceType type : program.getDeclaredTypes()) { |
| if (type instanceof JClassType) { |
| computeSourceType(type); |
| } |
| } |
| |
| for (JArrayType type : program.getAllArrayTypes()) { |
| computeSourceType(type); |
| } |
| |
| // pass our info to JProgram |
| program.initTypeInfo(castableTypeMaps); |
| |
| // JSO's marker queryId is -1 (used for array stores). |
| JClassType jsoType = program.getJavaScriptObject(); |
| if (jsoType != null) { |
| queryIds.put(jsoType, -1); |
| } |
| program.recordQueryIds(queryIds); |
| } |
| |
| /* |
| * If this expression could possibly generate an ArrayStoreException, we |
| * must record a query on the element type being assigned to. |
| */ |
| @Override |
| public void endVisit(JBinaryOperation x, Context ctx) { |
| if (x.getOp().isAssignment() && x.getLhs() instanceof JArrayRef) { |
| |
| // first, calculate the transitive closure of all possible runtime types |
| // the lhs could be |
| JArrayRef lhsArrayRef = (JArrayRef) x.getLhs(); |
| JType elementType = lhsArrayRef.getType(); |
| if (elementType instanceof JNullType) { |
| // will generate a null pointer exception instead |
| return; |
| } |
| |
| // primitives are statically correct |
| if (!(elementType instanceof JReferenceType)) { |
| return; |
| } |
| |
| // element type being final means the assignment is statically correct |
| if (((JReferenceType) elementType).isFinal()) { |
| return; |
| } |
| |
| /* |
| * For every instantiated array type that could -in theory- be the |
| * runtime type of the lhs, we must record a cast from the rhs to the |
| * prospective element type of the lhs. |
| */ |
| JTypeOracle typeOracle = program.typeOracle; |
| JType rhsType = x.getRhs().getType(); |
| assert (rhsType instanceof JReferenceType); |
| |
| JArrayType lhsArrayType = lhsArrayRef.getArrayType(); |
| for (JArrayType arrayType : instantiatedArrayTypes) { |
| if (typeOracle.canTheoreticallyCast(arrayType, lhsArrayType)) { |
| JType itElementType = arrayType.getElementType(); |
| if (itElementType instanceof JReferenceType) { |
| recordCast(itElementType, x.getRhs()); |
| } |
| } |
| } |
| } |
| } |
| |
| @Override |
| public void endVisit(JCastOperation x, Context ctx) { |
| if (disableCastChecking) { |
| return; |
| } |
| if (x.getCastType() != program.getTypeNull()) { |
| recordCast(x.getCastType(), x.getExpr()); |
| } |
| } |
| |
| @Override |
| public void endVisit(JInstanceOf x, Context ctx) { |
| assert (x.getTestType() != program.getTypeNull()); |
| recordCast(x.getTestType(), x.getExpr()); |
| } |
| |
| /** |
| * Create the data for JSON table to capture the mapping from a class to its |
| * query types. |
| */ |
| private void computeSourceType(JReferenceType type) { |
| if (type == null || alreadyRan.contains(type)) { |
| return; |
| } |
| assert (type == program.getRunTimeType(type)); |
| |
| alreadyRan.add(type); |
| |
| // Visit super type. |
| computeSourceType(type.getSuperClass()); |
| |
| if (!program.typeOracle.isInstantiatedType(type) |
| || program.isJavaScriptObject(type)) { |
| return; |
| } |
| |
| // Find all possible query types which I can satisfy |
| Set<JReferenceType> yesSet = null; |
| |
| // NOTE: non-deterministic iteration over HashSet and HashMap. This is |
| // okay here because we're just adding things to another HashSet. |
| for (JReferenceType qType : queriedTypes.keySet()) { |
| |
| Set<JReferenceType> querySet = queriedTypes.get(qType); |
| if (program.typeOracle.canTriviallyCast(type, qType)) { |
| |
| for (JReferenceType argType : querySet) { |
| |
| if (program.typeOracle.canTriviallyCast(type, argType)) { |
| if (yesSet == null) { |
| yesSet = new HashSet<JReferenceType>(); |
| } |
| yesSet.add(qType); |
| break; |
| } |
| } |
| } |
| } |
| |
| // Use a sparse array to sort my yes set. |
| JReferenceType[] yesArray = new JReferenceType[nextQueryId]; |
| if (yesSet != null) { |
| for (JReferenceType yesType : yesSet) { |
| yesArray[queryIds.get(yesType)] = yesType; |
| } |
| } |
| |
| // Create a sparse lookup object. |
| SourceInfo sourceInfo = program.createSourceInfoSynthetic( |
| AssignTypeCastabilityVisitor.class, "typeinfo lookup"); |
| JsonObject jsonObject = new JsonObject(sourceInfo, |
| program.getJavaScriptObject()); |
| // Start at 1; 0 is Object and always true. |
| for (int i = 1; i < nextQueryId; ++i) { |
| if (yesArray[i] != null) { |
| JIntLiteral labelExpr = program.getLiteralInt(i); |
| JIntLiteral valueExpr = program.getLiteralInt(1); |
| jsonObject.propInits.add(new JsonPropInit(sourceInfo, labelExpr, |
| valueExpr)); |
| } |
| } |
| |
| /* |
| * Don't add an entry for empty answer sets, except for Object and String |
| * which require entries. |
| */ |
| if (jsonObject.propInits.isEmpty() |
| && type != program.getTypeJavaLangObject() |
| && type != program.getTypeJavaLangString()) { |
| return; |
| } |
| |
| // add an entry for me |
| castableTypeMaps.put(type,jsonObject); |
| } |
| |
| private void recordCast(JType targetType, JExpression rhs) { |
| if (targetType instanceof JReferenceType) { |
| targetType = program.getRunTimeType((JReferenceType) targetType); |
| // unconditional cast b/c it would've been a semantic error earlier |
| JReferenceType rhsType = program.getRunTimeType((JReferenceType) rhs.getType()); |
| // don't record a type for trivial casts that won't generate code |
| if (program.typeOracle.canTriviallyCast(rhsType, |
| (JReferenceType) targetType)) { |
| return; |
| } |
| |
| // If the target type is a JavaScriptObject, don't record an id. |
| if (program.isJavaScriptObject(targetType)) { |
| return; |
| } |
| |
| recordCastInternal((JReferenceType) targetType, rhsType); |
| } |
| } |
| |
| private void recordCastInternal(JReferenceType toType, |
| JReferenceType rhsType) { |
| toType = program.getRunTimeType(toType); |
| rhsType = program.getRunTimeType(rhsType); |
| Set<JReferenceType> querySet = queriedTypes.get(toType); |
| if (querySet == null) { |
| queryIds.put(toType, nextQueryId++); |
| querySet = new HashSet<JReferenceType>(); |
| queriedTypes.put(toType, querySet); |
| } |
| querySet.add(rhsType); |
| } |
| } |
| |
| /** |
| * Explicitly convert any char or long type expressions within a concat |
| * operation into strings because normal JavaScript conversion does not work |
| * correctly. |
| */ |
| private class ConcatVisitor extends JModVisitor { |
| |
| @Override |
| public void endVisit(JBinaryOperation x, Context ctx) { |
| if (x.getOp() == JBinaryOperator.CONCAT) { |
| JExpression newLhs = convertString(x.getLhs()); |
| JExpression newRhs = convertString(x.getRhs()); |
| if (newLhs != x.getLhs() || newRhs != x.getRhs()) { |
| JBinaryOperation newExpr = new JBinaryOperation(x.getSourceInfo(), |
| program.getTypeJavaLangString(), JBinaryOperator.CONCAT, newLhs, |
| newRhs); |
| ctx.replaceMe(newExpr); |
| } |
| } else if (x.getOp() == JBinaryOperator.ASG_CONCAT) { |
| JExpression newRhs = convertString(x.getRhs()); |
| if (newRhs != x.getRhs()) { |
| JBinaryOperation newExpr = new JBinaryOperation(x.getSourceInfo(), |
| program.getTypeJavaLangString(), JBinaryOperator.ASG_CONCAT, |
| x.getLhs(), newRhs); |
| ctx.replaceMe(newExpr); |
| } |
| } |
| } |
| |
| private JExpression convertString(JExpression expr) { |
| JPrimitiveType charType = program.getTypePrimitiveChar(); |
| if (expr.getType() == charType) { |
| if (expr instanceof JCharLiteral) { |
| JCharLiteral charLit = (JCharLiteral) expr; |
| return program.getLiteralString(expr.getSourceInfo(), |
| new char[] {charLit.getValue()}); |
| } else { |
| // Replace with Cast.charToString(c) |
| JMethodCall call = new JMethodCall(expr.getSourceInfo(), null, |
| program.getIndexedMethod("Cast.charToString")); |
| call.addArg(expr); |
| return call; |
| } |
| } else if (expr.getType() == program.getTypePrimitiveLong()) { |
| // Replace with LongLib.toString(l) |
| JMethodCall call = new JMethodCall(expr.getSourceInfo(), null, |
| program.getIndexedMethod("LongLib.toString")); |
| call.addArg(expr); |
| return call; |
| } |
| return expr; |
| } |
| } |
| |
| /** |
| * Handle integral divide operations which may have floating point results. |
| */ |
| private class DivVisitor extends JModVisitor { |
| |
| @Override |
| public void endVisit(JBinaryOperation x, Context ctx) { |
| JType type = x.getType(); |
| if (x.getOp() == JBinaryOperator.DIV |
| && type != program.getTypePrimitiveFloat() |
| && type != program.getTypePrimitiveDouble()) { |
| /* |
| * If the numerator was already in range, we can assume the output is |
| * also in range. Therefore, we don't need to do the full conversion, |
| * but rather a narrowing int conversion instead. |
| */ |
| String methodName = "Cast.narrow_" + type.getName(); |
| JMethod castMethod = program.getIndexedMethod(methodName); |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, castMethod, |
| type); |
| x.setType(program.getTypePrimitiveDouble()); |
| call.addArg(x); |
| ctx.replaceMe(call); |
| } |
| } |
| } |
| |
| /** |
| * Replaces all casts and instanceof operations with calls to implementation |
| * methods. |
| */ |
| private class ReplaceTypeChecksVisitor extends JModVisitor { |
| |
| @Override |
| public void endVisit(JCastOperation x, Context ctx) { |
| JExpression replaceExpr; |
| JType toType = x.getCastType(); |
| JExpression expr = x.getExpr(); |
| if (disableCastChecking && toType instanceof JReferenceType) { |
| ctx.replaceMe(expr); |
| return; |
| } |
| if (toType instanceof JNullType) { |
| /* |
| * Magic: a null type cast means the user tried a cast that couldn't |
| * possibly work. Typically this means either the statically resolvable |
| * arg type is incompatible with the target type, or the target type was |
| * globally uninstantiable. We handle this cast by throwing a |
| * ClassCastException, unless the argument is null. |
| */ |
| JMethod method = program.getIndexedMethod("Cast.throwClassCastExceptionUnlessNull"); |
| /* |
| * Override the type of the magic method with the null type. |
| */ |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, method, |
| program.getTypeNull()); |
| call.addArg(expr); |
| replaceExpr = call; |
| } else if (toType instanceof JReferenceType) { |
| JExpression curExpr = expr; |
| JReferenceType refType = program.getRunTimeType((JReferenceType) toType); |
| JReferenceType argType = (JReferenceType) expr.getType(); |
| if (program.typeOracle.canTriviallyCast(argType, refType)) { |
| // just remove the cast |
| replaceExpr = curExpr; |
| } else { |
| |
| JMethod method; |
| boolean isJsoCast = program.isJavaScriptObject(refType); |
| if (isJsoCast) { |
| // A cast to a concrete JSO subtype |
| method = program.getIndexedMethod("Cast.dynamicCastJso"); |
| } else if (program.typeOracle.isDualJsoInterface(refType)) { |
| // An interface that should succeed when the object is a JSO |
| method = program.getIndexedMethod("Cast.dynamicCastAllowJso"); |
| } else { |
| // A regular cast |
| method = program.getIndexedMethod("Cast.dynamicCast"); |
| } |
| // override the type of the called method with the target cast type |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, method, |
| toType); |
| call.addArg(curExpr); |
| if (!isJsoCast) { |
| JIntLiteral qId = program.getLiteralInt(queryIds.get(refType)); |
| call.addArg(qId); |
| } |
| replaceExpr = call; |
| } |
| } else { |
| /* |
| * See JLS 5.1.3: if a cast narrows from one type to another, we must |
| * call a narrowing conversion function. EXCEPTION: we currently have no |
| * way to narrow double to float, so don't bother. |
| */ |
| JPrimitiveType tByte = program.getTypePrimitiveByte(); |
| JPrimitiveType tChar = program.getTypePrimitiveChar(); |
| JPrimitiveType tShort = program.getTypePrimitiveShort(); |
| JPrimitiveType tInt = program.getTypePrimitiveInt(); |
| JPrimitiveType tLong = program.getTypePrimitiveLong(); |
| JPrimitiveType tFloat = program.getTypePrimitiveFloat(); |
| JPrimitiveType tDouble = program.getTypePrimitiveDouble(); |
| JType fromType = expr.getType(); |
| |
| String methodName = null; |
| |
| if (tLong == fromType && tLong != toType) { |
| if (tByte == toType || tShort == toType || tChar == toType) { |
| /* |
| * We need a double call here, one to convert long->int, and another |
| * one to narrow. Construct the inner call here and fall through to |
| * do the narrowing conversion. |
| */ |
| JMethod castMethod = program.getIndexedMethod("LongLib.toInt"); |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, |
| castMethod); |
| call.addArg(expr); |
| expr = call; |
| fromType = tInt; |
| } else if (tInt == toType) { |
| methodName = "LongLib.toInt"; |
| } else if (tFloat == toType || tDouble == toType) { |
| methodName = "LongLib.toDouble"; |
| } |
| } |
| |
| if (toType == tLong && fromType != tLong) { |
| // Longs get special treatment. |
| if (tByte == fromType || tShort == fromType || tChar == fromType |
| || tInt == fromType) { |
| methodName = "LongLib.fromInt"; |
| } else if (tFloat == fromType || tDouble == fromType) { |
| methodName = "LongLib.fromDouble"; |
| } |
| } else if (tByte == fromType) { |
| if (tChar == toType) { |
| methodName = "Cast.narrow_" + toType.getName(); |
| } |
| } else if (tShort == fromType) { |
| if (tByte == toType || tChar == toType) { |
| methodName = "Cast.narrow_" + toType.getName(); |
| } |
| } else if (tChar == fromType) { |
| if (tByte == toType || tShort == toType) { |
| methodName = "Cast.narrow_" + toType.getName(); |
| } |
| } else if (tInt == fromType) { |
| if (tByte == toType || tShort == toType || tChar == toType) { |
| methodName = "Cast.narrow_" + toType.getName(); |
| } |
| } else if (tFloat == fromType || tDouble == fromType) { |
| if (tByte == toType || tShort == toType || tChar == toType |
| || tInt == toType) { |
| methodName = "Cast.round_" + toType.getName(); |
| } |
| } |
| |
| if (methodName != null) { |
| JMethod castMethod = program.getIndexedMethod(methodName); |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, |
| castMethod, toType); |
| call.addArg(expr); |
| replaceExpr = call; |
| } else { |
| // Just remove the cast |
| replaceExpr = expr; |
| } |
| } |
| ctx.replaceMe(replaceExpr); |
| } |
| |
| @Override |
| public void endVisit(JInstanceOf x, Context ctx) { |
| JReferenceType argType = (JReferenceType) x.getExpr().getType(); |
| JReferenceType toType = x.getTestType(); |
| // Only tests on run-time types are supported |
| assert (toType == program.getRunTimeType(toType)); |
| if (program.typeOracle.canTriviallyCast(argType, toType)) { |
| // trivially true if non-null; replace with a null test |
| JNullLiteral nullLit = program.getLiteralNull(); |
| JBinaryOperation eq = new JBinaryOperation(x.getSourceInfo(), |
| program.getTypePrimitiveBoolean(), JBinaryOperator.NEQ, |
| x.getExpr(), nullLit); |
| ctx.replaceMe(eq); |
| } else { |
| JMethod method; |
| boolean isJsoCast = false; |
| if (program.typeOracle.getSingleJsoImpl(toType) != null) { |
| method = program.getIndexedMethod("Cast.instanceOfOrJso"); |
| } else if (program.isJavaScriptObject(toType)) { |
| isJsoCast = true; |
| method = program.getIndexedMethod("Cast.instanceOfJso"); |
| } else { |
| method = program.getIndexedMethod("Cast.instanceOf"); |
| } |
| JMethodCall call = new JMethodCall(x.getSourceInfo(), null, method); |
| call.addArg(x.getExpr()); |
| if (!isJsoCast) { |
| JIntLiteral qId = program.getLiteralInt(queryIds.get(toType)); |
| call.addArg(qId); |
| } |
| ctx.replaceMe(call); |
| } |
| } |
| } |
| |
| public static void exec(JProgram program, boolean disableCastChecking) { |
| new CastNormalizer(program, disableCastChecking).execImpl(); |
| } |
| |
| private final boolean disableCastChecking; |
| |
| private final JProgram program; |
| |
| private Map<JReferenceType, Integer> queryIds = new IdentityHashMap<JReferenceType, Integer>(); |
| |
| private CastNormalizer(JProgram program, boolean disableCastChecking) { |
| this.program = program; |
| this.disableCastChecking = disableCastChecking; |
| } |
| |
| private void execImpl() { |
| { |
| ConcatVisitor visitor = new ConcatVisitor(); |
| visitor.accept(program); |
| } |
| { |
| DivVisitor visitor = new DivVisitor(); |
| visitor.accept(program); |
| } |
| { |
| AssignTypeCastabilityVisitor assigner = new AssignTypeCastabilityVisitor(); |
| assigner.accept(program); |
| assigner.computeTypeCastabilityMaps(); |
| } |
| { |
| ReplaceTypeChecksVisitor replacer = new ReplaceTypeChecksVisitor(); |
| replacer.accept(program); |
| } |
| } |
| |
| } |