Swift: Fix performance.

Author: geoffw0

swift/ql/lib/codeql/swift/security/SqlInjectionExtensions.qll

@@ -147,15 +147,23 @@ private class GrdbDefaultSqlInjectionSink extends SqlInjectionSink {
   }
 }
 
+/**
+ * A parameter that might be executed as SQL.
+ */
+pragma[noinline] predicate sqlLikeHeuristic(Callable f, int ix, ParamDecl pd) {
+  pd.getName() = "sql" and
+  pd = f.getParam(ix)
+}
+
 /**
  * An SQL injection sink that is determined by imprecise methods.
  */
 private class HeuristicSqlInjectionSink extends SqlInjectionSink {
   HeuristicSqlInjectionSink() {
     // by parameter name
-    exists(CallExpr ce, int ix, ParamDecl pd |
-      pd.getName() = "sql" and
-      pd = ce.getStaticTarget().getParam(ix) and
+    exists(CallExpr ce, Callable f, int ix |
+      sqlLikeHeuristic(f, ix, _) and
+      f = ce.getStaticTarget() and
       this.asExpr() = ce.getArgument(ix).getExpr()
     )
     or