Merge pull request #6755 from alexet/alexet/cache-params-string

Java: Fix more performance issues with future versions of codeql.

Author: aschackmull

java/ql/lib/semmle/code/java/dataflow/ExternalFlow.qll

@@ -641,6 +641,7 @@ private string paramsStringPart(Callable c, int i) {
  * Returns the empty string if the callable has no parameters.
  * Parameter types are represented by their type erasure.
  */
+cached
 string paramsString(Callable c) { result = concat(int i | | paramsStringPart(c, i) order by i) }
 
 private Element interpretElement0(

java/ql/lib/semmle/code/java/frameworks/android/Android.qll

@@ -6,19 +6,29 @@ import java
 import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.xml.AndroidManifest
 
+/**
+ * Gets a transitive superType avoiding magic optimisation
+ */
+pragma[nomagic]
+private RefType getASuperTypePlus(RefType t) { result = t.getASupertype+() }
+
+/**
+ * Gets a reflexive/transitive superType avoiding magic optimisation
+ */
+pragma[inline]
+private RefType getASuperTypeStar(RefType t) { result = getASuperTypePlus(t) or result = t }
+
 /**
  * An Android component. That is, either an activity, a service,
  * a broadcast receiver, or a content provider.
  */
 class AndroidComponent extends Class {
   AndroidComponent() {
-    // The casts here are due to misoptimisation if they are missing
-    // but are not needed semantically.
-    this.(Class).getASupertype*().hasQualifiedName("android.app", "Activity") or
-    this.(Class).getASupertype*().hasQualifiedName("android.app", "Service") or
-    this.(Class).getASupertype*().hasQualifiedName("android.content", "BroadcastReceiver") or
-    this.(Class).getASupertype*().hasQualifiedName("android.content", "ContentProvider") or
-    this.(Class).getASupertype*().hasQualifiedName("android.content", "ContentResolver")
+    getASuperTypeStar(this).hasQualifiedName("android.app", "Activity") or
+    getASuperTypeStar(this).hasQualifiedName("android.app", "Service") or
+    getASuperTypeStar(this).hasQualifiedName("android.content", "BroadcastReceiver") or
+    getASuperTypeStar(this).hasQualifiedName("android.content", "ContentProvider") or
+    getASuperTypeStar(this).hasQualifiedName("android.content", "ContentResolver")
   }
 
   /** The XML element corresponding to this Android component. */
@@ -52,25 +62,25 @@ class ExportableAndroidComponent extends AndroidComponent {
 
 /** An Android activity. */
 class AndroidActivity extends ExportableAndroidComponent {
-  AndroidActivity() { this.getASupertype*().hasQualifiedName("android.app", "Activity") }
+  AndroidActivity() { getASuperTypeStar(this).hasQualifiedName("android.app", "Activity") }
 }
 
 /** An Android service. */
 class AndroidService extends ExportableAndroidComponent {
-  AndroidService() { this.getASupertype*().hasQualifiedName("android.app", "Service") }
+  AndroidService() { getASuperTypeStar(this).hasQualifiedName("android.app", "Service") }
 }
 
 /** An Android broadcast receiver. */
 class AndroidBroadcastReceiver extends ExportableAndroidComponent {
   AndroidBroadcastReceiver() {
-    this.getASupertype*().hasQualifiedName("android.content", "BroadcastReceiver")
+    getASuperTypeStar(this).hasQualifiedName("android.content", "BroadcastReceiver")
   }
 }
 
 /** An Android content provider. */
 class AndroidContentProvider extends ExportableAndroidComponent {
   AndroidContentProvider() {
-    this.getASupertype*().hasQualifiedName("android.content", "ContentProvider")
+    getASuperTypeStar(this).hasQualifiedName("android.content", "ContentProvider")
   }
 
   /**
@@ -85,7 +95,7 @@ class AndroidContentProvider extends ExportableAndroidComponent {
 /** An Android content resolver. */
 class AndroidContentResolver extends AndroidComponent {
   AndroidContentResolver() {
-    this.getASupertype*().hasQualifiedName("android.content", "ContentResolver")
+    getASuperTypeStar(this).hasQualifiedName("android.content", "ContentResolver")
   }
 }
 

java/ql/src/Violations of Best Practice/Naming Conventions/ConfusingOverloading.ql

@@ -50,6 +50,7 @@ private predicate whitelist(string name) { name = "visit" }
  * Method `m` has name `name`, number of parameters `numParams`
  * and is declared in `t` or inherited from a supertype of `t`.
  */
+pragma[nomagic]
 private predicate candidateMethod(RefType t, Method m, string name, int numParam) {
   exists(Method n | n.getSourceDeclaration() = m | t.inherits(n)) and
   m.getName() = name and