src/main/java/com/android/tools/r8/ir/code/AbstractValueSupplier.java

// Copyright (c) 2023, 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.graph.AppView;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.ir.analysis.value.AbstractValue;

public interface AbstractValueSupplier {

  AbstractValueSupplier UNKNOWN = (value, appView, context) -> AbstractValue.unknown();
  AbstractValueSupplier SHALLOW =
      (value, appView, context) -> value.getAbstractValue(appView, context, unknown());

  AbstractValue getAbstractValue(Value value, AppView<?> appView, ProgramMethod context);

  /**
   * Returns an {@link AbstractValueSupplier} that supplies UNKNOWN in the recursive call to {@link
   * Value#getAbstractValue}, so that a shallow value is computed. This is to prevent that computing
   * the abstract value can end up evaluating large arithmetic expressions, which should ideally
   * only be done during constant propagation.
   */
  static AbstractValueSupplier shallow() {
    return SHALLOW;
  }

  static AbstractValueSupplier unknown() {
    return UNKNOWN;
  }
}