blob: a2f872ebd4a792544315a4d2e0eb6a564367dfd9 [file] [log] [blame]
// Copyright (c) 2017, 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.code;
import com.android.tools.r8.cf.LoadStoreHelper;
import com.android.tools.r8.cf.code.CfStackInstruction;
import com.android.tools.r8.errors.Unreachable;
import com.android.tools.r8.graph.AppView;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.ir.conversion.CfBuilder;
import com.android.tools.r8.ir.conversion.DexBuilder;
import com.android.tools.r8.ir.optimize.DeadCodeRemover.DeadInstructionResult;
import com.android.tools.r8.ir.optimize.Inliner.ConstraintWithTarget;
import com.android.tools.r8.ir.optimize.InliningConstraints;
public class Pop extends Instruction {
public Pop(Value src) {
super(null, src);
assert src.isValueOnStack();
}
@Override
public int opcode() {
return Opcodes.POP;
}
@Override
public <T> T accept(InstructionVisitor<T> visitor) {
return visitor.visit(this);
}
@Override
protected void addInValue(Value value) {
if (value.hasUsersInfo()) {
super.addInValue(value);
} else {
// Overriding IR addInValue since userinfo is cleared.
inValues.add(value);
}
}
@Override
public boolean isPop() {
return true;
}
@Override
public Pop asPop() {
return this;
}
@Override
public boolean identicalNonValueNonPositionParts(Instruction other) {
return other.isPop();
}
@Override
public int maxInValueRegister() {
throw new Unreachable();
}
@Override
public int maxOutValueRegister() {
throw new Unreachable();
}
@Override
public ConstraintWithTarget inliningConstraint(
InliningConstraints inliningConstraints, ProgramMethod context) {
return inliningConstraints.forPop();
}
@Override
public void buildDex(DexBuilder builder) {
throw new Unreachable("This classfile-specific IR should not be inserted in the Dex backend.");
}
@Override
public void buildCf(CfBuilder builder) {
builder.add(CfStackInstruction.popType(inValues.get(0).outType()));
}
@Override
public void insertLoadAndStores(InstructionListIterator it, LoadStoreHelper helper) {
throw new Unreachable("This IR must not be inserted before load and store insertion.");
}
@Override
public boolean hasInvariantOutType() {
return true;
}
@Override
public DeadInstructionResult canBeDeadCode(AppView<?> appView, IRCode code) {
// Pop cannot be dead code as it modifies the stack height.
return DeadInstructionResult.notDead();
}
@Override
public boolean instructionMayTriggerMethodInvocation(AppView<?> appView, ProgramMethod context) {
return false;
}
}