mirror of
https://github.com/Eaglercraft-TeaVM-Fork/eagler-teavm.git
synced 2024-12-22 16:14:10 -08:00
Add nullness checker
This commit is contained in:
Alexey Andreev
Alexey Andreev
parent
0b4629d959
commit
2894c541f7
|
|
@ -60,6 +60,11 @@ public class Program implements ProgramReader {
|
|||
return basicBlocks.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<BasicBlock> getBasicBlocks() {
|
||||
return basicBlocks;
|
||||
}
|
||||
|
||||
public void deleteVariable(int index) {
|
||||
Variable variable = variables.get(index);
|
||||
if (variable == null) {
|
||||
|
|
|
|||
|
|
@ -15,15 +15,13 @@
|
|||
*/
|
||||
package org.teavm.model;
|
||||
|
||||
/**
|
||||
*
|
||||
* @author Alexey Andreev
|
||||
*/
|
||||
public interface ProgramReader {
|
||||
int basicBlockCount();
|
||||
|
||||
BasicBlockReader basicBlockAt(int index);
|
||||
|
||||
Iterable<? extends BasicBlockReader> getBasicBlocks();
|
||||
|
||||
int variableCount();
|
||||
|
||||
VariableReader variableAt(int index);
|
||||
|
|
|
|||
289
core/src/main/java/org/teavm/model/analysis/NullnessChecker.java
Normal file
289
core/src/main/java/org/teavm/model/analysis/NullnessChecker.java
Normal file
|
|
@ -0,0 +1,289 @@
|
|||
/*
|
||||
* Copyright 2016 Alexey Andreev.
|
||||
*
|
||||
* 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 org.teavm.model.analysis;
|
||||
|
||||
import java.util.ArrayDeque;
|
||||
import java.util.HashSet;
|
||||
import java.util.List;
|
||||
import java.util.Queue;
|
||||
import java.util.Set;
|
||||
import org.teavm.common.DominatorTree;
|
||||
import org.teavm.common.Graph;
|
||||
import org.teavm.common.GraphBuilder;
|
||||
import org.teavm.common.GraphUtils;
|
||||
import org.teavm.model.BasicBlock;
|
||||
import org.teavm.model.BasicBlockReader;
|
||||
import org.teavm.model.FieldReference;
|
||||
import org.teavm.model.Incoming;
|
||||
import org.teavm.model.MethodReference;
|
||||
import org.teavm.model.Phi;
|
||||
import org.teavm.model.Program;
|
||||
import org.teavm.model.ValueType;
|
||||
import org.teavm.model.VariableReader;
|
||||
import org.teavm.model.instructions.AbstractInstructionReader;
|
||||
import org.teavm.model.instructions.ArrayElementType;
|
||||
import org.teavm.model.instructions.BinaryBranchingCondition;
|
||||
import org.teavm.model.instructions.BranchingCondition;
|
||||
import org.teavm.model.instructions.InvocationType;
|
||||
import org.teavm.model.util.ProgramUtils;
|
||||
|
||||
public class NullnessChecker {
|
||||
Set<Incoming> notNullIncomings;
|
||||
List<List<Incoming>> phiOutputs;
|
||||
boolean[] notNull;
|
||||
boolean[] nullLiteral;
|
||||
GraphBuilder graphBuilder;
|
||||
|
||||
public boolean[] check(Program program) {
|
||||
notNullIncomings = new HashSet<>();
|
||||
notNull = new boolean[program.variableCount()];
|
||||
nullLiteral = new boolean[program.variableCount()];
|
||||
phiOutputs = ProgramUtils.getPhiOutputs(program);
|
||||
graphBuilder = new GraphBuilder(program.variableCount());
|
||||
|
||||
Graph cfg = ProgramUtils.buildControlFlowGraph(program);
|
||||
DominatorTree dom = GraphUtils.buildDominatorTree(cfg);
|
||||
Graph domGraph = GraphUtils.buildDominatorGraph(dom, cfg.size());
|
||||
|
||||
Step[] stack = new Step[cfg.size() * 2];
|
||||
int head = 0;
|
||||
stack[head++] = new Step(0, notNull.clone());
|
||||
|
||||
while (head > 0) {
|
||||
Step step = stack[--head];
|
||||
int node = step.node;
|
||||
|
||||
BasicBlock block = program.basicBlockAt(node);
|
||||
InstructionReaderImpl reader = new InstructionReaderImpl(step.nonNull);
|
||||
block.readAllInstructions(reader);
|
||||
|
||||
for (Phi phi : block.getPhis()) {
|
||||
for (Incoming incoming : phi.getIncomings()) {
|
||||
graphBuilder.addEdge(incoming.getValue().getIndex(), phi.getReceiver().getIndex());
|
||||
}
|
||||
}
|
||||
|
||||
for (int successor : domGraph.outgoingEdges(node)) {
|
||||
boolean[] nextNonNull = step.nonNull.clone();
|
||||
if (successor == reader.notNullTarget && reader.notNullVariable >= 0) {
|
||||
nextNonNull[reader.notNullVariable] = true;
|
||||
}
|
||||
stack[head++] = new Step(successor, nextNonNull);
|
||||
}
|
||||
}
|
||||
|
||||
propagateNullness(graphBuilder.build());
|
||||
|
||||
boolean[] result = notNull;
|
||||
|
||||
notNullIncomings = null;
|
||||
notNull = null;
|
||||
nullLiteral = null;
|
||||
phiOutputs = null;
|
||||
graphBuilder = null;
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
private void propagateNullness(Graph graph) {
|
||||
Queue<Integer> worklist = new ArrayDeque<>();
|
||||
for (int i = 0; i < notNull.length; ++i) {
|
||||
if (notNull[i] && graph.outgoingEdgesCount(i) > 0) {
|
||||
for (int j : graph.outgoingEdges(i)) {
|
||||
if (!notNull[j]) {
|
||||
worklist.add(j);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
while (!worklist.isEmpty()) {
|
||||
int node = worklist.remove();
|
||||
if (notNull[node]) {
|
||||
continue;
|
||||
}
|
||||
notNull[node] = true;
|
||||
for (int next : graph.outgoingEdges(node)) {
|
||||
if (!notNull[next]) {
|
||||
worklist.add(next);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
class InstructionReaderImpl extends AbstractInstructionReader {
|
||||
boolean[] currentNotNull;
|
||||
int notNullTarget;
|
||||
int notNullVariable = -1;
|
||||
|
||||
public InstructionReaderImpl(boolean[] currentNotNull) {
|
||||
this.currentNotNull = currentNotNull;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void nullConstant(VariableReader receiver) {
|
||||
nullLiteral[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void classConstant(VariableReader receiver, ValueType cst) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void stringConstant(VariableReader receiver, String cst) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void assign(VariableReader receiver, VariableReader assignee) {
|
||||
if (currentNotNull[assignee.getIndex()]) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
graphBuilder.addEdge(assignee.getIndex(), receiver.getIndex());
|
||||
}
|
||||
|
||||
@Override
|
||||
public void invoke(VariableReader receiver, VariableReader instance, MethodReference method,
|
||||
List<? extends VariableReader> arguments, InvocationType type) {
|
||||
if (instance != null) {
|
||||
markAsCurrentNotNull(instance);
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public void getField(VariableReader receiver, VariableReader instance, FieldReference field,
|
||||
ValueType fieldType) {
|
||||
if (instance != null) {
|
||||
markAsCurrentNotNull(instance);
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public void putField(VariableReader instance, FieldReference field, VariableReader value, ValueType fieldType) {
|
||||
if (instance != null) {
|
||||
markAsCurrentNotNull(instance);
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public void getElement(VariableReader receiver, VariableReader array, VariableReader index,
|
||||
ArrayElementType elementType) {
|
||||
markAsCurrentNotNull(array);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void putElement(VariableReader array, VariableReader index, VariableReader value,
|
||||
ArrayElementType elementType) {
|
||||
markAsCurrentNotNull(array);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void create(VariableReader receiver, String type) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void createArray(VariableReader receiver, ValueType itemType,
|
||||
List<? extends VariableReader> dimensions) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void createArray(VariableReader receiver, ValueType itemType, VariableReader size) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void arrayLength(VariableReader receiver, VariableReader array) {
|
||||
markAsCurrentNotNull(array);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void unwrapArray(VariableReader receiver, VariableReader array, ArrayElementType elementType) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void nullCheck(VariableReader receiver, VariableReader value) {
|
||||
notNull[receiver.getIndex()] = true;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void jumpIf(BranchingCondition cond, VariableReader operand, BasicBlockReader consequent,
|
||||
BasicBlockReader alternative) {
|
||||
switch (cond) {
|
||||
case NULL:
|
||||
notNullVariable = operand.getIndex();
|
||||
notNullTarget = alternative.getIndex();
|
||||
break;
|
||||
case NOT_NULL:
|
||||
notNullVariable = operand.getIndex();
|
||||
notNullTarget = consequent.getIndex();
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public void jumpIf(BinaryBranchingCondition cond, VariableReader first, VariableReader second,
|
||||
BasicBlockReader consequent, BasicBlockReader alternative) {
|
||||
switch (cond) {
|
||||
case REFERENCE_EQUAL:
|
||||
if (nullLiteral[first.getIndex()]) {
|
||||
notNullVariable = second.getIndex();
|
||||
} else if (nullLiteral[second.getIndex()]) {
|
||||
notNullVariable = first.getIndex();
|
||||
}
|
||||
notNullTarget = alternative.getIndex();
|
||||
break;
|
||||
case REFERENCE_NOT_EQUAL:
|
||||
if (nullLiteral[first.getIndex()]) {
|
||||
notNullVariable = second.getIndex();
|
||||
} else if (nullLiteral[second.getIndex()]) {
|
||||
notNullVariable = first.getIndex();
|
||||
}
|
||||
notNullTarget = consequent.getIndex();
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
private void markAsCurrentNotNull(VariableReader variable) {
|
||||
if (!currentNotNull[variable.getIndex()]) {
|
||||
currentNotNull[variable.getIndex()] = true;
|
||||
List<Incoming> outputs = phiOutputs.get(variable.getIndex());
|
||||
if (outputs != null) {
|
||||
for (Incoming output : outputs) {
|
||||
notNullIncomings.add(output);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static class Step {
|
||||
int node;
|
||||
boolean[] nonNull;
|
||||
|
||||
public Step(int node, boolean[] nonNull) {
|
||||
this.node = node;
|
||||
this.nonNull = nonNull;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -15,10 +15,6 @@
|
|||
*/
|
||||
package org.teavm.model.instructions;
|
||||
|
||||
/**
|
||||
*
|
||||
* @author Alexey Andreev
|
||||
*/
|
||||
public enum BinaryBranchingCondition {
|
||||
EQUAL,
|
||||
NOT_EQUAL,
|
||||
|
|
|
|||
|
|
@ -15,10 +15,6 @@
|
|||
*/
|
||||
package org.teavm.model.instructions;
|
||||
|
||||
/**
|
||||
*
|
||||
* @author Alexey Andreev
|
||||
*/
|
||||
public enum BranchingCondition {
|
||||
EQUAL,
|
||||
NOT_EQUAL,
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user