Merge "Redundant const number removal"
diff --git a/src/main/java/com/android/tools/r8/ir/analysis/type/TypeLatticeElement.java b/src/main/java/com/android/tools/r8/ir/analysis/type/TypeLatticeElement.java
index 1544570..9c3bcc3 100644
--- a/src/main/java/com/android/tools/r8/ir/analysis/type/TypeLatticeElement.java
+++ b/src/main/java/com/android/tools/r8/ir/analysis/type/TypeLatticeElement.java
@@ -107,7 +107,6 @@
throw new Unreachable("unless a new type lattice is introduced.");
}
-
public static TypeLatticeElement join(
Iterable<TypeLatticeElement> typeLattices, AppInfo appInfo) {
TypeLatticeElement result = BOTTOM;
diff --git a/src/main/java/com/android/tools/r8/ir/code/If.java b/src/main/java/com/android/tools/r8/ir/code/If.java
index 2979039..25d1fc4 100644
--- a/src/main/java/com/android/tools/r8/ir/code/If.java
+++ b/src/main/java/com/android/tools/r8/ir/code/If.java
@@ -142,6 +142,7 @@
return super.toString()
+ " "
+ type
+ + (isZeroTest() ? "Z" : " ")
+ " block "
+ getTrueTarget().getNumberAsString()
+ " (fallthrough "
diff --git a/src/main/java/com/android/tools/r8/ir/code/Value.java b/src/main/java/com/android/tools/r8/ir/code/Value.java
index f95b988..374acd5 100644
--- a/src/main/java/com/android/tools/r8/ir/code/Value.java
+++ b/src/main/java/com/android/tools/r8/ir/code/Value.java
@@ -797,7 +797,17 @@
}
public boolean knownToBeBoolean() {
- return knownToBeBoolean;
+ if (knownToBeBoolean) {
+ return true;
+ }
+ if (getTypeLattice().isInt()) {
+ Value aliasedValue = getAliasedValue();
+ if (!aliasedValue.isPhi() && aliasedValue.definition.isConstNumber()) {
+ ConstNumber definition = aliasedValue.definition.asConstNumber();
+ return definition.isZero() || definition.getRawValue() == 1;
+ }
+ }
+ return false;
}
public void markAsThis(boolean receiverCanBeNull) {
diff --git a/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java b/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
index b1ea3f9..7b55543 100644
--- a/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
+++ b/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
@@ -997,6 +997,7 @@
codeRewriter.rewriteSwitch(code);
codeRewriter.processMethodsNeverReturningNormally(code);
codeRewriter.simplifyIf(code);
+ codeRewriter.redundantConstNumberRemoval(code);
new RedundantFieldLoadElimination(appInfo, code, enableWholeProgramOptimizations).run();
if (options.testing.invertConditionals) {
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/CodeRewriter.java b/src/main/java/com/android/tools/r8/ir/optimize/CodeRewriter.java
index 7447f76..3227d45 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/CodeRewriter.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/CodeRewriter.java
@@ -26,6 +26,7 @@
import com.android.tools.r8.graph.DexEncodedMethod.TrivialInitializer.TrivialInstanceInitializer;
import com.android.tools.r8.graph.DexField;
import com.android.tools.r8.graph.DexItemFactory;
+import com.android.tools.r8.graph.DexItemFactory.ThrowableMethods;
import com.android.tools.r8.graph.DexMethod;
import com.android.tools.r8.graph.DexProto;
import com.android.tools.r8.graph.DexString;
@@ -120,6 +121,8 @@
import it.unimi.dsi.fastutil.ints.IntArrayList;
import it.unimi.dsi.fastutil.ints.IntIterator;
import it.unimi.dsi.fastutil.ints.IntList;
+import it.unimi.dsi.fastutil.longs.Long2ReferenceMap;
+import it.unimi.dsi.fastutil.longs.Long2ReferenceOpenHashMap;
import it.unimi.dsi.fastutil.objects.Object2IntLinkedOpenHashMap;
import it.unimi.dsi.fastutil.objects.Object2IntMap;
import it.unimi.dsi.fastutil.objects.Reference2IntMap;
@@ -3144,6 +3147,210 @@
simplifyIfWithKnownCondition(code, block, theIf, theIf.targetFromCondition(cond));
}
+ /**
+ * This optimization exploits that we can sometimes learn the constant value of an SSA value that
+ * flows into an if-eq of if-neq instruction.
+ *
+ * <p>Consider the following example:
+ *
+ * <pre>
+ * 1. if (obj != null) {
+ * 2. return doStuff();
+ * 3. }
+ * 4. return null;
+ * </pre>
+ *
+ * <p>Since we know that `obj` is null in all blocks that are dominated by the false-target of the
+ * if-instruction in line 1, we can safely replace the null-constant in line 4 by `obj`, and
+ * thereby save a const-number instruction.
+ */
+ public void redundantConstNumberRemoval(IRCode code) {
+ Supplier<Long2ReferenceMap<List<ConstNumber>>> constantsByValue =
+ Suppliers.memoize(() -> getConstantsByValue(code));
+ Supplier<DominatorTree> dominatorTree = Suppliers.memoize(() -> new DominatorTree(code));
+
+ boolean changed = false;
+ for (BasicBlock block : code.blocks) {
+ Instruction lastInstruction = block.getInstructions().getLast();
+ if (!lastInstruction.isIf()) {
+ continue;
+ }
+
+ If ifInstruction = lastInstruction.asIf();
+ Type type = ifInstruction.getType();
+
+ Value lhs = ifInstruction.inValues().get(0);
+ Value rhs = !ifInstruction.isZeroTest() ? ifInstruction.inValues().get(1) : null;
+
+ if (!ifInstruction.isZeroTest() && !lhs.isConstNumber() && !rhs.isConstNumber()) {
+ // We can only conclude anything from an if-instruction if it is a zero-test or if one of
+ // the two operands is a constant.
+ continue;
+ }
+
+ // If the type is neither EQ nor NE, we cannot conclude anything about any of the in-values
+ // of the if-instruction from the outcome of the if-instruction.
+ if (type != Type.EQ && type != Type.NE) {
+ continue;
+ }
+
+ BasicBlock trueTarget, falseTarget;
+ if (type == Type.EQ) {
+ trueTarget = ifInstruction.getTrueTarget();
+ falseTarget = ifInstruction.fallthroughBlock();
+ } else {
+ falseTarget = ifInstruction.getTrueTarget();
+ trueTarget = ifInstruction.fallthroughBlock();
+ }
+
+ if (ifInstruction.isZeroTest()) {
+ changed |=
+ replaceDominatedConstNumbers(0, lhs, trueTarget, constantsByValue, dominatorTree);
+ if (lhs.knownToBeBoolean()) {
+ changed |=
+ replaceDominatedConstNumbers(1, lhs, falseTarget, constantsByValue, dominatorTree);
+ }
+ } else {
+ assert rhs != null;
+ if (lhs.isConstNumber()) {
+ ConstNumber lhsAsNumber = lhs.getConstInstruction().asConstNumber();
+ changed |=
+ replaceDominatedConstNumbers(
+ lhsAsNumber.getRawValue(), rhs, trueTarget, constantsByValue, dominatorTree);
+ if (lhs.knownToBeBoolean() && rhs.knownToBeBoolean()) {
+ changed |=
+ replaceDominatedConstNumbers(
+ negateBoolean(lhsAsNumber), rhs, falseTarget, constantsByValue, dominatorTree);
+ }
+ } else {
+ assert rhs.isConstNumber();
+ ConstNumber rhsAsNumber = rhs.getConstInstruction().asConstNumber();
+ changed |=
+ replaceDominatedConstNumbers(
+ rhsAsNumber.getRawValue(), lhs, trueTarget, constantsByValue, dominatorTree);
+ if (lhs.knownToBeBoolean() && rhs.knownToBeBoolean()) {
+ changed |=
+ replaceDominatedConstNumbers(
+ negateBoolean(rhsAsNumber), lhs, falseTarget, constantsByValue, dominatorTree);
+ }
+ }
+ }
+
+ if (constantsByValue.get().isEmpty()) {
+ break;
+ }
+ }
+
+ if (changed) {
+ code.removeAllTrivialPhis();
+ }
+ assert code.isConsistentSSA();
+ }
+
+ private static Long2ReferenceMap<List<ConstNumber>> getConstantsByValue(IRCode code) {
+ // A map from the raw value of constants in `code` to the const number instructions that define
+ // the given raw value (irrespective of the type of the raw value).
+ Long2ReferenceMap<List<ConstNumber>> constantsByValue = new Long2ReferenceOpenHashMap<>();
+
+ // Initialize `constantsByValue`.
+ Iterable<Instruction> instructions = code::instructionIterator;
+ for (Instruction instruction : instructions) {
+ if (instruction.isConstNumber()) {
+ ConstNumber constNumber = instruction.asConstNumber();
+ if (constNumber.outValue().hasLocalInfo()) {
+ // Not necessarily constant, because it could be changed in the debugger.
+ continue;
+ }
+ long rawValue = constNumber.getRawValue();
+ if (constantsByValue.containsKey(rawValue)) {
+ constantsByValue.get(rawValue).add(constNumber);
+ } else {
+ List<ConstNumber> list = new ArrayList<>();
+ list.add(constNumber);
+ constantsByValue.put(rawValue, list);
+ }
+ }
+ }
+ return constantsByValue;
+ }
+
+ private static int negateBoolean(ConstNumber number) {
+ assert number.outValue().knownToBeBoolean();
+ return number.getRawValue() == 0 ? 1 : 0;
+ }
+
+ private boolean replaceDominatedConstNumbers(
+ long withValue,
+ Value newValue,
+ BasicBlock dominator,
+ Supplier<Long2ReferenceMap<List<ConstNumber>>> constantsByValueSupplier,
+ Supplier<DominatorTree> dominatorTree) {
+ if (newValue.hasLocalInfo()) {
+ // We cannot replace a constant with a value that has local info, because that could change
+ // debugging behavior.
+ return false;
+ }
+
+ Long2ReferenceMap<List<ConstNumber>> constantsByValue = constantsByValueSupplier.get();
+ List<ConstNumber> constantsWithValue = constantsByValue.get(withValue);
+ if (constantsWithValue == null || constantsWithValue.isEmpty()) {
+ return false;
+ }
+
+ boolean changed = false;
+
+ ListIterator<ConstNumber> constantWithValueIterator = constantsWithValue.listIterator();
+ while (constantWithValueIterator.hasNext()) {
+ ConstNumber constNumber = constantWithValueIterator.next();
+ Value value = constNumber.outValue();
+ assert !value.hasLocalInfo();
+ assert constNumber.getRawValue() == withValue;
+
+ BasicBlock block = constNumber.getBlock();
+
+ // If the following condition does not hold, then the if-instruction does not dominate the
+ // block containing the constant, although the true or false target does.
+ if (block == dominator && block.getPredecessors().size() != 1) {
+ // This should generally not happen, but it is possible to write bytecode where it does.
+ assert false;
+ continue;
+ }
+
+ if (value.knownToBeBoolean() && !newValue.knownToBeBoolean()) {
+ // We cannot replace a boolean by a none-boolean since that can lead to verification
+ // errors. For example, the following code fails with "register v1 has type Imprecise
+ // Constant: 127 but expected Boolean return-1nr".
+ //
+ // public boolean convertIntToBoolean(int v1) {
+ // const/4 v0, 0x1
+ // if-eq v1, v0, :eq_true
+ // const/4 v1, 0x0
+ // :eq_true
+ // return v1
+ // }
+ continue;
+ }
+
+ if (dominatorTree.get().dominatedBy(block, dominator)) {
+ if (newValue.getTypeLattice().lessThanOrEqual(value.getTypeLattice(), appInfo)) {
+ value.replaceUsers(newValue);
+ block.listIterator(constNumber).removeOrReplaceByDebugLocalRead();
+ constantWithValueIterator.remove();
+ changed = true;
+ } else if (value.getTypeLattice().isNullType()) {
+ // TODO(b/120257211): Need a mechanism to determine if `newValue` can be used at all of
+ // the use sites of `value` without introducing a type error.
+ }
+ }
+ }
+
+ if (constantsWithValue.isEmpty()) {
+ constantsByValue.remove(withValue);
+ }
+
+ return changed;
+ }
+
// Find all method invocations that never returns normally, split the block
// after each such invoke instruction and follow it with a block throwing a
// null value (which should result in NPE). Note that this throw is not
@@ -3439,7 +3646,7 @@
// Note that addSuppressed() and getSuppressed() methods are final in
// Throwable, so these changes don't have to worry about overrides.
public void rewriteThrowableAddAndGetSuppressed(IRCode code) {
- DexItemFactory.ThrowableMethods throwableMethods = dexItemFactory.throwableMethods;
+ ThrowableMethods throwableMethods = dexItemFactory.throwableMethods;
for (BasicBlock block : code.blocks) {
InstructionListIterator iterator = block.listIterator();
@@ -3579,7 +3786,7 @@
} else {
// Insert "if (argument != null) ...".
successor = block.unlinkSingleSuccessor();
- If theIf = new If(If.Type.NE, argument);
+ If theIf = new If(Type.NE, argument);
theIf.setPosition(position);
BasicBlock ifBlock = BasicBlock.createIfBlock(code.blocks.size(), theIf);
code.blocks.add(ifBlock);
diff --git a/src/test/java/com/android/tools/r8/TestRunResult.java b/src/test/java/com/android/tools/r8/TestRunResult.java
index 65a57e6..a032fd6 100644
--- a/src/test/java/com/android/tools/r8/TestRunResult.java
+++ b/src/test/java/com/android/tools/r8/TestRunResult.java
@@ -29,6 +29,10 @@
abstract RR self();
+ public AndroidApp app() {
+ return app;
+ }
+
public String getStdOut() {
return result.stdout;
}
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java b/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
index c140610..798f1b0 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
@@ -10,10 +10,12 @@
import static com.android.tools.r8.ir.analysis.type.TypeLatticeElement.LONG;
import static org.junit.Assert.assertEquals;
+import com.android.tools.r8.NeverInline;
import com.android.tools.r8.ir.analysis.AnalysisTestBase;
import com.android.tools.r8.ir.code.ConstNumber;
import com.android.tools.r8.ir.code.IRCode;
import com.android.tools.r8.ir.code.Instruction;
+import com.android.tools.r8.utils.StringUtils;
import com.google.common.collect.Streams;
import java.util.function.Consumer;
import org.junit.Test;
@@ -25,6 +27,21 @@
}
@Test
+ public void testOutput() throws Exception {
+ String expectedOutput =
+ StringUtils.lines("1", "2", "3", "1.0", "1.0", "2.0", "1", "1", "2", "1.0", "1.0", "2.0");
+
+ testForJvm().addTestClasspath().run(TestClass.class).assertSuccessWithOutput(expectedOutput);
+
+ testForR8(Backend.DEX)
+ .addInnerClasses(ConstrainedPrimitiveTypeTest.class)
+ .addKeepMainRule(TestClass.class)
+ .enableInliningAnnotations()
+ .run(TestClass.class)
+ .assertSuccessWithOutput(expectedOutput);
+ }
+
+ @Test
public void testIntWithInvokeUser() throws Exception {
buildAndCheckIR("intWithInvokeUserTest", testInspector(INT, 1));
}
@@ -83,26 +100,47 @@
static class TestClass {
- public static void intWithInvokeUserTest() {
- int x = 1;
- Integer.toString(x);
+ public static void main(String[] args) {
+ boolean unknownButTrue = args.length >= 0;
+ boolean unknownButFalse = args.length < 0;
+ intWithInvokeUserTest();
+ intWithIndirectInvokeUserTest(unknownButTrue);
+ intWithIndirectInvokeUserTest(unknownButFalse);
+ floatWithInvokeUserTest();
+ floatWithIndirectInvokeUserTest(unknownButTrue);
+ floatWithIndirectInvokeUserTest(unknownButFalse);
+ longWithInvokeUserTest();
+ longWithIndirectInvokeUserTest(unknownButTrue);
+ longWithIndirectInvokeUserTest(unknownButFalse);
+ doubleWithInvokeUserTest();
+ doubleWithIndirectInvokeUserTest(unknownButTrue);
+ doubleWithIndirectInvokeUserTest(unknownButFalse);
}
+ @NeverInline
+ public static void intWithInvokeUserTest() {
+ int x = 1;
+ System.out.println(Integer.toString(x));
+ }
+
+ @NeverInline
public static void intWithIndirectInvokeUserTest(boolean unknown) {
int x;
if (unknown) {
- x = 1;
- } else {
x = 2;
+ } else {
+ x = 3;
}
- Integer.toString(x);
+ System.out.println(Integer.toString(x));
}
+ @NeverInline
public static void floatWithInvokeUserTest() {
float x = 1f;
- Float.toString(x);
+ System.out.println(Float.toString(x));
}
+ @NeverInline
public static void floatWithIndirectInvokeUserTest(boolean unknown) {
float x;
if (unknown) {
@@ -110,14 +148,16 @@
} else {
x = 2f;
}
- Float.toString(x);
+ System.out.println(Float.toString(x));
}
+ @NeverInline
public static void longWithInvokeUserTest() {
long x = 1L;
- Long.toString(x);
+ System.out.println(Long.toString(x));
}
+ @NeverInline
public static void longWithIndirectInvokeUserTest(boolean unknown) {
long x;
if (unknown) {
@@ -125,14 +165,16 @@
} else {
x = 2L;
}
- Long.toString(x);
+ System.out.println(Long.toString(x));
}
+ @NeverInline
public static void doubleWithInvokeUserTest() {
double x = 1.0;
- Double.toString(x);
+ System.out.println(Double.toString(x));
}
+ @NeverInline
public static void doubleWithIndirectInvokeUserTest(boolean unknown) {
double x;
if (unknown) {
@@ -140,7 +182,7 @@
} else {
x = 2f;
}
- Double.toString(x);
+ System.out.println(Double.toString(x));
}
}
}
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java b/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java
new file mode 100644
index 0000000..fc382ee
--- /dev/null
+++ b/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java
@@ -0,0 +1,248 @@
+// Copyright (c) 2019, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.ir.optimize;
+
+import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import com.android.tools.r8.NeverInline;
+import com.android.tools.r8.R8TestRunResult;
+import com.android.tools.r8.TestBase;
+import com.android.tools.r8.ir.code.BasicBlock;
+import com.android.tools.r8.ir.code.IRCode;
+import com.android.tools.r8.ir.code.Instruction;
+import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.google.common.collect.Streams;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
+
+@RunWith(Parameterized.class)
+public class RedundantConstNumberRemovalTest extends TestBase {
+
+ private final Backend backend;
+
+ @Parameters(name = "Backend: {0}")
+ public static Backend[] data() {
+ return Backend.values();
+ }
+
+ public RedundantConstNumberRemovalTest(Backend backend) {
+ this.backend = backend;
+ }
+
+ @Test
+ public void test() throws Exception {
+ String expectedOutput =
+ StringUtils.lines(
+ "true", "true", "true", "true", "true", "true", "true", "true", "true", "true", "true",
+ "true", "true", "true", "true", "true");
+
+ if (backend == Backend.CF) {
+ testForJvm().addTestClasspath().run(TestClass.class).assertSuccessWithOutput(expectedOutput);
+ }
+
+ R8TestRunResult result =
+ testForR8(backend)
+ .addInnerClasses(RedundantConstNumberRemovalTest.class)
+ .addKeepMainRule(TestClass.class)
+ .enableInliningAnnotations()
+ .run(TestClass.class)
+ .assertSuccessWithOutput(expectedOutput);
+
+ ClassSubject classSubject = result.inspector().clazz(TestClass.class);
+ verifyBooleanCheckTest(classSubject.uniqueMethodWithName("booleanCheckTest"));
+ verifyBooleanCheckTest(classSubject.uniqueMethodWithName("negateBooleanCheckTest"));
+ verifyIntCheckTest(classSubject.uniqueMethodWithName("intCheckTest"));
+ verifyIntCheckTest(classSubject.uniqueMethodWithName("negateIntCheckTest"));
+ verifyNullCheckTest(classSubject.uniqueMethodWithName("nullCheckTest"));
+ verifyNullCheckTest(classSubject.uniqueMethodWithName("invertedNullCheckTest"));
+ verifyNullCheckTest(classSubject.uniqueMethodWithName("nonNullCheckTest"));
+ verifyNullCheckWithWrongTypeTest(
+ classSubject.uniqueMethodWithName("nullCheckWithWrongTypeTest"));
+ }
+
+ private void verifyBooleanCheckTest(MethodSubject methodSubject) {
+ assertThat(methodSubject, isPresent());
+
+ if (backend == Backend.DEX) {
+ // Check that the generated code for booleanCheckTest() only has a return instruction.
+ assertEquals(1, methodSubject.streamInstructions().count());
+ assertTrue(methodSubject.iterateInstructions().next().isReturn());
+ } else {
+ assert backend == Backend.CF;
+ // Check that the generated code for booleanCheckTest() only has return instructions that
+ // return the argument.
+ // TODO(christofferqa): CF backend does not share identical prefix of successors.
+ IRCode code = methodSubject.buildIR();
+ assertTrue(
+ Streams.stream(code.instructionIterator())
+ .filter(Instruction::isReturn)
+ .allMatch(
+ instruction -> instruction.asReturn().returnValue().definition.isArgument()));
+ }
+ }
+
+ private void verifyIntCheckTest(MethodSubject methodSubject) {
+ assertThat(methodSubject, isPresent());
+ IRCode code = methodSubject.buildIR();
+
+ if (backend == Backend.DEX) {
+ // Only a single basic block.
+ assertEquals(1, code.blocks.size());
+ // The block only has three instructions.
+ BasicBlock entryBlock = code.blocks.get(0);
+ assertEquals(3, entryBlock.getInstructions().size());
+ // The first one is the `argument` instruction.
+ Instruction argument = entryBlock.getInstructions().getFirst();
+ assertTrue(argument.isArgument());
+ // The next one is a `const-number` instruction is not used for anything.
+ // TODO(christofferqa): D8 should be able to get rid of the unused const-number instruction.
+ Instruction unused = entryBlock.getInstructions().get(1);
+ assertTrue(unused.isConstNumber());
+ assertEquals(0, unused.outValue().numberOfAllUsers());
+ // The `return` instruction returns the argument.
+ Instruction ret = entryBlock.getInstructions().getLast();
+ assertTrue(ret.isReturn());
+ assertTrue(ret.asReturn().returnValue().definition.isArgument());
+ } else {
+ // Check that the generated code for intCheckTest() only has return instructions that
+ // return the argument.
+ // TODO(christofferqa): CF backend does not share identical prefix of successors.
+ assertTrue(
+ Streams.stream(code.instructionIterator())
+ .filter(Instruction::isReturn)
+ .allMatch(
+ instruction -> instruction.asReturn().returnValue().definition.isArgument()));
+ }
+ }
+
+ private void verifyNullCheckTest(MethodSubject methodSubject) {
+ // Check that the generated code for nullCheckTest() only has a single `const-null` instruction.
+ assertThat(methodSubject, isPresent());
+ assertEquals(
+ 1, methodSubject.streamInstructions().filter(InstructionSubject::isConstNull).count());
+
+ // Also check that one of the return instructions actually returns the argument.
+ IRCode code = methodSubject.buildIR();
+ assertEquals(1, code.collectArguments().size());
+ // TODO(b/120257211): D8 should replace `return null` by `return arg`.
+ assertFalse(
+ code.collectArguments().get(0).uniqueUsers().stream().anyMatch(Instruction::isReturn));
+ }
+
+ private void verifyNullCheckWithWrongTypeTest(MethodSubject methodSubject) {
+ // Check that the generated code for nullCheckWithWrongTypeTest() still has a `return null`
+ // instruction.
+ assertThat(methodSubject, isPresent());
+ IRCode code = methodSubject.buildIR();
+
+ // Check that the code returns null.
+ assertTrue(
+ Streams.stream(code.instructionIterator())
+ .anyMatch(
+ instruction ->
+ instruction.isReturn()
+ && instruction.asReturn().returnValue().definition.isConstNumber()));
+
+ // Also check that none of the return instructions actually returns the argument.
+ assertEquals(1, code.collectArguments().size());
+ assertTrue(
+ code.collectArguments().get(0).uniqueUsers().stream().noneMatch(Instruction::isReturn));
+ }
+
+ static class TestClass {
+
+ public static void main(String[] args) {
+ System.out.println(booleanCheckTest(true) == true);
+ System.out.println(booleanCheckTest(false) == false);
+ System.out.println(negateBooleanCheckTest(true) == true);
+ System.out.println(negateBooleanCheckTest(false) == false);
+ System.out.println(intCheckTest(0) == 0);
+ System.out.println(intCheckTest(42) == 42);
+ System.out.println(negateIntCheckTest(0) == 0);
+ System.out.println(negateIntCheckTest(42) == 42);
+ System.out.println(nullCheckTest(new Object()) != null);
+ System.out.println(nullCheckTest(null) == null);
+ System.out.println(invertedNullCheckTest(new Object()) != null);
+ System.out.println(invertedNullCheckTest(null) == null);
+ System.out.println(nonNullCheckTest(new Object()) != null);
+ System.out.println(nonNullCheckTest(null) == null);
+ System.out.println(nullCheckWithWrongTypeTest(new Object()) != null);
+ System.out.println(nullCheckWithWrongTypeTest(null) == null);
+ }
+
+ @NeverInline
+ private static boolean booleanCheckTest(boolean x) {
+ if (x) {
+ return true; // should be replaced by `x`.
+ }
+ return false; // should be replaced by `x`.
+ }
+
+ @NeverInline
+ private static boolean negateBooleanCheckTest(boolean x) {
+ if (!x) {
+ return false; // should be replaced by `x`
+ }
+ return true; // should be replaced by `x`
+ }
+
+ @NeverInline
+ private static int intCheckTest(int x) {
+ if (x == 42) {
+ return 42; // should be replaced by `x`.
+ }
+ return x;
+ }
+
+ @NeverInline
+ private static int negateIntCheckTest(int x) {
+ if (x != 42) {
+ return x;
+ }
+ return 42; // should be replaced by `x`
+ }
+
+ @NeverInline
+ private static Object nullCheckTest(Object x) {
+ if (x != null) {
+ return new Object();
+ }
+ return null; // should be replaced by `x`.
+ }
+
+ @NeverInline
+ private static Object invertedNullCheckTest(Object x) {
+ if (null == x) {
+ return null; // should be replaced by `x`.
+ }
+ return new Object();
+ }
+
+ @NeverInline
+ private static Object nonNullCheckTest(Object x) {
+ if (x == null) {
+ return null; // should be replaced by `x`
+ }
+ return new Object();
+ }
+
+ @NeverInline
+ private static Throwable nullCheckWithWrongTypeTest(Object x) {
+ if (x != null) {
+ return new Throwable();
+ }
+ return null; // cannot be replaced by `x` because Object is not a subtype of Throwable.
+ }
+ }
+}
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/AbsentMethodSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/AbsentMethodSubject.java
index c2ced01..8e24088 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/AbsentMethodSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/AbsentMethodSubject.java
@@ -6,12 +6,18 @@
import com.android.tools.r8.errors.Unreachable;
import com.android.tools.r8.graph.DexEncodedMethod;
+import com.android.tools.r8.ir.code.IRCode;
import com.android.tools.r8.naming.MemberNaming.MethodSignature;
import com.android.tools.r8.naming.MemberNaming.Signature;
public class AbsentMethodSubject extends MethodSubject {
@Override
+ public IRCode buildIR() {
+ throw new Unreachable("Cannot build IR for an absent method");
+ }
+
+ @Override
public boolean isPresent() {
return false;
}
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/CfInstructionSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/CfInstructionSubject.java
index 924ec2d..ee2155e 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/CfInstructionSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/CfInstructionSubject.java
@@ -4,7 +4,6 @@
package com.android.tools.r8.utils.codeinspector;
-import static org.junit.Assert.assertTrue;
import com.android.tools.r8.cf.code.CfArithmeticBinop;
import com.android.tools.r8.cf.code.CfCheckCast;
@@ -31,7 +30,6 @@
import com.android.tools.r8.cf.code.CfStackInstruction;
import com.android.tools.r8.cf.code.CfSwitch;
import com.android.tools.r8.cf.code.CfThrow;
-import com.android.tools.r8.graph.CfCode;
import com.android.tools.r8.graph.DexField;
import com.android.tools.r8.graph.DexMethod;
import com.android.tools.r8.ir.code.Monitor.Type;
@@ -167,6 +165,11 @@
}
@Override
+ public boolean isReturn() {
+ return instruction instanceof CfReturn;
+ }
+
+ @Override
public boolean isReturnVoid() {
return instruction instanceof CfReturnVoid;
}
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
index 1f520ff..9983320 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
@@ -58,7 +58,7 @@
public class CodeInspector {
- private final DexApplication application;
+ final DexApplication application;
final DexItemFactory dexItemFactory;
private final ClassNameMapper mapping;
final Map<String, String> originalToObfuscatedMapping;
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/DexInstructionSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/DexInstructionSubject.java
index 6d463da..7051226 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/DexInstructionSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/DexInstructionSubject.java
@@ -70,6 +70,7 @@
import com.android.tools.r8.code.NewInstance;
import com.android.tools.r8.code.Nop;
import com.android.tools.r8.code.PackedSwitch;
+import com.android.tools.r8.code.Return;
import com.android.tools.r8.code.ReturnObject;
import com.android.tools.r8.code.ReturnVoid;
import com.android.tools.r8.code.Sget;
@@ -275,6 +276,11 @@
}
@Override
+ public boolean isReturn() {
+ return instruction instanceof Return;
+ }
+
+ @Override
public boolean isReturnVoid() {
return instruction instanceof ReturnVoid;
}
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
index 6c23162..796532d 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
@@ -9,6 +9,7 @@
import com.android.tools.r8.code.Instruction;
import com.android.tools.r8.errors.Unimplemented;
import com.android.tools.r8.errors.Unreachable;
+import com.android.tools.r8.graph.AppInfo;
import com.android.tools.r8.graph.CfCode;
import com.android.tools.r8.graph.Code;
import com.android.tools.r8.graph.DexCode;
@@ -17,10 +18,14 @@
import com.android.tools.r8.graph.DexDebugPositionState;
import com.android.tools.r8.graph.DexEncodedMethod;
import com.android.tools.r8.graph.DexString;
+import com.android.tools.r8.graph.GraphLense;
import com.android.tools.r8.graph.JarCode;
+import com.android.tools.r8.ir.code.IRCode;
import com.android.tools.r8.naming.MemberNaming;
import com.android.tools.r8.naming.MemberNaming.MethodSignature;
import com.android.tools.r8.naming.signature.GenericSignatureParser;
+import com.android.tools.r8.origin.Origin;
+import com.android.tools.r8.utils.InternalOptions;
import it.unimi.dsi.fastutil.objects.Reference2IntMap;
import it.unimi.dsi.fastutil.objects.Reference2IntOpenHashMap;
import java.util.Arrays;
@@ -41,6 +46,19 @@
}
@Override
+ public IRCode buildIR() {
+ DexEncodedMethod method = getMethod();
+ return method
+ .getCode()
+ .buildIR(
+ method,
+ new AppInfo(codeInspector.application),
+ GraphLense.getIdentityLense(),
+ new InternalOptions(),
+ Origin.unknown());
+ }
+
+ @Override
public boolean isPresent() {
return true;
}
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/InstructionSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/InstructionSubject.java
index 6abeacf..294cc8c 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/InstructionSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/InstructionSubject.java
@@ -58,6 +58,8 @@
boolean isIfEqz();
+ boolean isReturn();
+
boolean isReturnVoid();
boolean isReturnObject();
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/MethodSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/MethodSubject.java
index b0d2c9b..8fb4001 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/MethodSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/MethodSubject.java
@@ -5,6 +5,7 @@
package com.android.tools.r8.utils.codeinspector;
import com.android.tools.r8.graph.DexEncodedMethod;
+import com.android.tools.r8.ir.code.IRCode;
import com.android.tools.r8.naming.MemberNaming.MethodSignature;
import com.google.common.collect.Streams;
import java.util.Iterator;
@@ -13,6 +14,8 @@
public abstract class MethodSubject extends MemberSubject {
+ public abstract IRCode buildIR();
+
public abstract boolean isAbstract();
public abstract boolean isBridge();
