DfaExpressionFactory: do not eagerly resolve qualifier for special field

Fixes performance degradation on long method chains
SpecialField API polishing

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

@@ -1123,13 +1123,6 @@ public class DfaMemoryStateImpl implements DfaMemoryState {
     if (constValue != null) {
       return constValue;
     }
-    DfaVariableValue qualifier = var.getQualifier();
-    if (qualifier != null) {
-      DfaValue value = SpecialField.tryCreateValue(qualifier, var.getPsiVariable());
-      if (value != null) {
-        return value;
-      }
-    }
     return var;
   }
 

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

@@ -7,7 +7,10 @@ import com.intellij.psi.*;
 import com.intellij.psi.util.PsiUtil;
 import com.siyeh.ig.psiutils.ExpressionUtils;
 import com.siyeh.ig.psiutils.MethodUtils;
+import one.util.streamex.StreamEx;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.Arrays;
 import java.util.List;
@@ -22,10 +25,10 @@ import static com.intellij.codeInspection.dataFlow.MethodContract.ValueConstrain
 public enum SpecialField implements DfaVariableSource {
   ARRAY_LENGTH(null, "length", true, LongRangeSet.indexRange()) {
     @Override
-    public boolean isMyAccessor(PsiModifierListOwner accessor) {
-      return accessor instanceof PsiField && "length".equals(((PsiField)accessor).getName()) &&
+    boolean isMyAccessor(PsiMember accessor) {
+      return accessor instanceof PsiField && "length".equals(accessor.getName()) &&
              JavaPsiFacade.getElementFactory(accessor.getProject()).getArrayClass(PsiUtil.getLanguageLevel(accessor)) ==
-             ((PsiField)accessor).getContainingClass();
+             accessor.getContainingClass();
     }
 
     @Override
@@ -98,21 +101,20 @@ public enum SpecialField implements DfaVariableSource {
    * @param accessor accessor to test to test
    * @return true if supplied accessor can be used to read this special field
    */
-  public boolean isMyAccessor(PsiModifierListOwner accessor) {
+  boolean isMyAccessor(PsiMember accessor) {
     return accessor instanceof PsiMethod && MethodUtils.methodMatches((PsiMethod)accessor, myClassName, null, myMethodName);
   }
 
-  public static DfaValue tryCreateValue(DfaValue qualifier, PsiElement element) {
-    if (qualifier == null) return null;
-    DfaValueFactory factory = qualifier.getFactory();
-    if (factory == null) return null;
-    if (!(element instanceof PsiVariable) && !(element instanceof PsiMethod)) return null;
-    for (SpecialField field : values()) {
-      if (field.isMyAccessor((PsiModifierListOwner)element)) {
-        return field.createValue(factory, qualifier);
-      }
-    }
-    return null;
+  /**
+   * Finds a special field which corresponds to given accessor (method or field)
+   * @param accessor accessor to find a special field for
+   * @return found special field or null if accessor cannot be used to access a special field
+   */
+  @Contract("null -> null")
+  @Nullable
+  public static SpecialField findSpecialField(PsiElement accessor) {
+    if (!(accessor instanceof PsiMember)) return null;
+    return StreamEx.of(values()).findFirst(sf -> sf.isMyAccessor((PsiMember)accessor)).orElse(null);
   }
 
   /**

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

@@ -503,9 +503,9 @@ public class StandardInstructionVisitor extends InstructionVisitor {
 
     if (methodType == MethodCallInstruction.MethodType.METHOD_REFERENCE_CALL && qualifierValue instanceof DfaVariableValue) {
       PsiMethod method = instruction.getTargetMethod();
-      DfaValue value = SpecialField.tryCreateValue(qualifierValue, method);
-      if (value != null) {
-        return value;
+      SpecialField field = SpecialField.findSpecialField(method);
+      if (field != null) {
+        return field.createValue(factory, qualifierValue);
       }
       DfaVariableSource source = DfaExpressionFactory.getAccessedVariableOrGetter(method);
       if (source != null) {

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/instructions/MethodCallInstruction.java

@@ -199,8 +199,7 @@ public class MethodCallInstruction extends Instruction {
 
   private boolean isPureCall() {
     if (myTargetMethod == null) return false;
-    return ControlFlowAnalyzer.isPure(myTargetMethod) ||
-           Arrays.stream(SpecialField.values()).anyMatch(sf -> sf.isMyAccessor(myTargetMethod));
+    return ControlFlowAnalyzer.isPure(myTargetMethod) || SpecialField.findSpecialField(myTargetMethod) != null;
   }
 
   @Nullable

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaExpressionFactory.java

@@ -197,8 +197,11 @@ public class DfaExpressionFactory {
   private DfaValue createFromSpecialField(PsiReferenceExpression refExpr) {
     PsiElement target = refExpr.resolve();
     if (!(target instanceof PsiModifierListOwner)) return null;
+    SpecialField sf = SpecialField.findSpecialField(target);
+    if (sf == null) return null;
     DfaVariableValue qualifier = getQualifierVariable(refExpr.getQualifierExpression());
-    return SpecialField.tryCreateValue(qualifier, target);
+    if (qualifier == null) return null;
+    return sf.createValue(myFactory, qualifier);
   }
 
   @Contract("null -> null")