[java-dfa] Properly balance stack when increment/decrement variable is unresolved

Found by property tests

GitOrigin-RevId: 581bc8d7a12cc43037a3936126a68cdf3678e884

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/java/ControlFlowAnalyzer.java

@@ -2172,6 +2172,8 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
     }
     PsiPrimitiveType unboxedType = PsiPrimitiveType.getOptionallyUnboxedType(operandType);
     if (unboxedType == null) {
+      // Unknown type; likely erroneous code: replace old_value with unknown
+      addInstruction(new PopInstruction());
       pushUnknown();
     } else {
       generateBoxingUnboxingInstructionFor(operand, unboxedType);

java/java-tests/testData/inspection/dataFlow/fixture/IncompleteLoop.java

@@ -0,0 +1,10 @@
+import java.util.*;
+
+class Test {
+
+  void test(int last)
+  {
+    for (; <error descr="Cannot resolve symbol 'i'">i</error> < last; <error descr="Cannot resolve symbol 'i'">i</error>++) {
+    }
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowRangeAnalysisTest.java

@@ -89,4 +89,5 @@ public class DataFlowRangeAnalysisTest extends DataFlowInspectionTestCase {
   public void testFloatingPointCasts() { doTest(); }
   public void testFloatingPointMaxLoop() { doTest(); }
   public void testStringIndexOfRelation() { doTest(); }
+  public void testIncompleteLoop() { doTest(); }
 }