Cleanup memory location states

base/src/main/java/proguard/analysis/cpa/jvm/domain/memory/JvmMemoryLocationTransferRelation.java

@@ -39,7 +39,6 @@
 import proguard.analysis.cpa.bam.ExpandOperator;
 import proguard.analysis.cpa.bam.ReduceOperator;
 import proguard.analysis.cpa.defaults.LatticeAbstractState;
-import proguard.analysis.cpa.defaults.MemoryLocation;
 import proguard.analysis.cpa.defaults.ProgramLocationDependentReachedSet;
 import proguard.analysis.cpa.defaults.SetAbstractState;
 import proguard.analysis.cpa.interfaces.AbstractState;
@@ -85,7 +84,7 @@
 /**
  * The {@link JvmMemoryLocationTransferRelation} computes the backward successors of an {@link
  * JvmMemoryLocationAbstractState} for a given instruction. A backward successor is a memory
- * location which may have contributed to the value of the current {@link MemoryLocation}.
+ * location which may have contributed to the value of the current {@link JvmMemoryLocation}.
  *
  * <p>The transfer relation uses a {@link BamCache} containing the results of an analysis in order
  * to calculate the successors {@link JvmMemoryLocationAbstractState}:

base/src/main/java/proguard/analysis/cpa/jvm/state/JvmAbstractState.java

@@ -32,7 +32,9 @@
  * The {@link JvmAbstractState} consists of the method frame {@link JvmFrameAbstractState} and the
  * heap {@link JvmHeapAbstractState}.
  *
- * @author Dmitry Ivanov
+ * @param <StateT> The type of the states contained in the JVM state. e.g., for taint analysis this
+ *     would be a {@link proguard.analysis.cpa.defaults.SetAbstractState} containing the taints and
+ *     for value analysis a {@link proguard.analysis.cpa.jvm.domain.value.ValueAbstractState}.
  */
 public class JvmAbstractState<StateT extends LatticeAbstractState<StateT>>
     implements LatticeAbstractState<JvmAbstractState<StateT>>,

base/src/main/java/proguard/analysis/cpa/jvm/witness/JvmHeapLocation.java

@@ -26,11 +26,7 @@
 import proguard.analysis.cpa.jvm.domain.reference.Reference;
 import proguard.analysis.cpa.jvm.state.JvmAbstractState;
 
-/**
- * The {@link JvmHeapLocation} is a memory location corresponding to a dynamic memory entity.
- *
- * @author Dmitry Ivanov
- */
+/** The {@link JvmHeapLocation} is a memory location corresponding to a dynamic memory entity. */
 public class JvmHeapLocation extends JvmMemoryLocation {
 
   public final SetAbstractState<Reference> reference;
@@ -49,9 +45,9 @@ public JvmHeapLocation(SetAbstractState<Reference> reference, String field) {
   // implementations for MemoryLocation
 
   @Override
-  public <T extends LatticeAbstractState> T extractValueOrDefault(
-      JvmAbstractState abstractState, T defaultValue) {
-    return (T) abstractState.getHeap().getFieldOrDefault(reference, field, defaultValue);
+  public <T extends LatticeAbstractState<T>> T extractValueOrDefault(
+      JvmAbstractState<T> jvmState, T defaultValue) {
+    return jvmState.getHeap().getFieldOrDefault(reference, field, defaultValue);
   }
 
   // implementations for Object

base/src/main/java/proguard/analysis/cpa/jvm/witness/JvmLocalVariableLocation.java

@@ -22,11 +22,7 @@
 import proguard.analysis.cpa.defaults.LatticeAbstractState;
 import proguard.analysis.cpa.jvm.state.JvmAbstractState;
 
-/**
- * The {@link JvmLocalVariableLocation} is a memory location at the local variable array.
- *
- * @author Dmitry Ivanov
- */
+/** The {@link JvmLocalVariableLocation} is a memory location at the local variable array. */
 public class JvmLocalVariableLocation extends JvmMemoryLocation {
 
   public final int index;
@@ -43,9 +39,9 @@ public JvmLocalVariableLocation(int index) {
   // implementations for MemoryLocation
 
   @Override
-  public <T extends LatticeAbstractState> T extractValueOrDefault(
-      JvmAbstractState abstractState, T defaultValue) {
-    return (T) abstractState.getVariableOrDefault(index, defaultValue);
+  public <T extends LatticeAbstractState<T>> T extractValueOrDefault(
+      JvmAbstractState<T> jvmState, T defaultValue) {
+    return jvmState.getVariableOrDefault(index, defaultValue);
   }
 
   // implementations for Object

base/src/main/java/proguard/analysis/cpa/jvm/witness/JvmMemoryLocation.java

@@ -19,17 +19,37 @@
 package proguard.analysis.cpa.jvm.witness;
 
 import proguard.analysis.cpa.defaults.LatticeAbstractState;
-import proguard.analysis.cpa.defaults.MemoryLocation;
-import proguard.analysis.cpa.jvm.cfa.edges.JvmCfaEdge;
-import proguard.analysis.cpa.jvm.cfa.nodes.JvmCfaNode;
 import proguard.analysis.cpa.jvm.state.JvmAbstractState;
-import proguard.classfile.MethodSignature;
 
 /**
- * A {@link JvmMemoryLocation} is a {@link MemoryLocation} specific to JVM.
- *
- * @author Dmitry Ivanov
+ * A {@link JvmMemoryLocation} points at a specific location in a certain state of the Jvm. For
+ * example a {@link JvmStackLocation} with index 0 indicates the top of the stack.
  */
-public abstract class JvmMemoryLocation
-    extends MemoryLocation<
-        JvmCfaNode, JvmCfaEdge, MethodSignature, LatticeAbstractState, JvmAbstractState> {}
+public abstract class JvmMemoryLocation {
+
+  /**
+   * Given a JVM state, extract its content in the position represented by this {@link
+   * JvmMemoryLocation}.
+   *
+   * @param jvmState The state from which the value is extracted.
+   * @param defaultValue The value returned if it's not possible to extract the value.
+   * @return The value from the JVM abstract state for the memory location represented by this
+   *     object. Or default value if not possible.
+   * @param <T> The type of the states contained in the JVM state. e.g., for taint analysis this
+   *     would be a {@link proguard.analysis.cpa.defaults.SetAbstractState} containing the taints
+   *     and for value analysis a {@link proguard.analysis.cpa.jvm.domain.value.ValueAbstractState}.
+   */
+  public abstract <T extends LatticeAbstractState<T>> T extractValueOrDefault(
+      JvmAbstractState<T> jvmState, T defaultValue);
+
+  // implementations for Object
+
+  @Override
+  public abstract boolean equals(Object obj);
+
+  @Override
+  public abstract int hashCode();
+
+  @Override
+  public abstract String toString();
+}

base/src/main/java/proguard/analysis/cpa/jvm/witness/JvmStackLocation.java

@@ -25,8 +25,6 @@
 /**
  * The {@link JvmStackLocation} is a memory location at the operand stack. Indexing starts from the
  * top of the stack.
- *
- * @author Dmitry Ivanov
  */
 public class JvmStackLocation extends JvmMemoryLocation {
 
@@ -44,9 +42,9 @@ public JvmStackLocation(int index) {
   // implementations for MemoryLocation
 
   @Override
-  public <T extends LatticeAbstractState> T extractValueOrDefault(
-      JvmAbstractState abstractState, T defaultValue) {
-    return (T) abstractState.peekOrDefault(index, defaultValue);
+  public <T extends LatticeAbstractState<T>> T extractValueOrDefault(
+      JvmAbstractState<T> jvmState, T defaultValue) {
+    return jvmState.peekOrDefault(index, defaultValue);
   }
 
   /** Returns the stack index from the top. */

base/src/main/java/proguard/analysis/cpa/jvm/witness/JvmStaticFieldLocation.java

@@ -23,8 +23,6 @@
 
 /**
  * The {@link JvmStaticFieldLocation} is a memory location corresponding to a public static field.
- *
- * @author Dmitry Ivanov
  */
 public class JvmStaticFieldLocation extends JvmMemoryLocation {
 
@@ -42,9 +40,9 @@ public JvmStaticFieldLocation(String fqn) {
   // implementations for MemoryLocation
 
   @Override
-  public <T extends LatticeAbstractState> T extractValueOrDefault(
-      JvmAbstractState abstractState, T defaultValue) {
-    return (T) abstractState.getStaticOrDefault(fqn, defaultValue);
+  public <T extends LatticeAbstractState<T>> T extractValueOrDefault(
+      JvmAbstractState<T> jvmState, T defaultValue) {
+    return jvmState.getStaticOrDefault(fqn, defaultValue);
   }
 
   // implementations for Object

docs/md/releasenotes.md

@@ -21,6 +21,12 @@
 - Move classes related to `Model` to the `proguard.evaluation.value.object.model` package.
 - `StringSharer` now uses a string pool to share strings, instead of traversing references.
 
+### API changes for the dataflow analysis code
+There are several changes to the dataflow analysis code with the objective of eliminating unnecessary abstraction and 
+make its usage easier. This includes:
+- Remove `MemoryLocation`, use `JvmMemoryLocation` instead.
+- Make `JvmMemoryLocation` independent of the type of value contained in the analysis' state. The type of the value now needs only to be provided when calling `extractValueOrDefault`. 
+
 ## Version 9.1.6
 
 ### Java support