[perf] Use native instanceof in NodeGroup::isStmtAwareNode (#8746)

Author: TomasVotruba

bench/node_group_is_stmt_aware_bench.php

@@ -0,0 +1,73 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Benchmark for NodeGroup::isStmtAwareNode().
+ *
+ * Called per node on the traversal hot path (top call count in a full profile). It previously used
+ * array_any() over the STMTS_AWARE class list with a closure doing a dynamic `$node instanceof $class`
+ * per element. The change uses native instanceof via match(true): no per-element closure call, no
+ * dynamic instanceof, same subclass semantics.
+ *
+ * This bench calls it over a realistic node mix - mostly non-stmt-aware nodes (the worst case, which
+ * exhausts every instanceof) plus a couple of matches.
+ *
+ * Run on both branches to compare:
+ *   php bench/node_group_is_stmt_aware_bench.php
+ *
+ * Reports CPU time (user+sys) and wall time; CPU is the reliable metric, wall is noisy under
+ * concurrent load.
+ */
+
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\Identifier;
+use PhpParser\Node\Scalar\String_;
+use PhpParser\Node\Stmt\ClassMethod;
+use PhpParser\Node\Stmt\If_;
+use Rector\PhpParser\Enum\NodeGroup;
+
+require __DIR__ . '/../vendor/autoload.php';
+
+const REPEAT = 300000;
+
+$nodes = [];
+for ($i = 0; $i < 20; ++$i) {
+    $nodes[] = new Variable('x');
+    $nodes[] = new String_('s');
+    $nodes[] = new Identifier('id');
+}
+
+$nodes[] = new ClassMethod('m');
+$nodes[] = new If_(new Variable('c'));
+
+$cpuSeconds = static function (): float {
+    $usage = getrusage();
+    return $usage['ru_utime.tv_sec'] + $usage['ru_utime.tv_usec'] / 1_000_000
+        + $usage['ru_stime.tv_sec'] + $usage['ru_stime.tv_usec'] / 1_000_000;
+};
+
+$run = static function () use ($nodes): void {
+    foreach ($nodes as $node) {
+        NodeGroup::isStmtAwareNode($node);
+    }
+};
+
+// warm up
+$run();
+
+$wallStart = microtime(true);
+$cpuStart = $cpuSeconds();
+
+for ($repeat = 0; $repeat < REPEAT; ++$repeat) {
+    $run();
+}
+
+$cpu = $cpuSeconds() - $cpuStart;
+$wall = microtime(true) - $wallStart;
+
+$totalCalls = REPEAT * count($nodes);
+
+printf('nodes: %d, repeats: %d, calls: %d%s', count($nodes), REPEAT, $totalCalls, PHP_EOL);
+printf('CPU:  %.4f s  (%.4f us/call)%s', $cpu, $cpu / $totalCalls * 1_000_000, PHP_EOL);
+printf('wall: %.4f s%s', $wall, PHP_EOL);

src/PhpParser/Enum/NodeGroup.php

@@ -82,6 +82,28 @@ final class NodeGroup
 
     public static function isStmtAwareNode(Node $node): bool
     {
-        return array_any(self::STMTS_AWARE, fn (string $stmtAwareClass): bool => $node instanceof $stmtAwareClass);
+        // native instanceof instead of array_any() over STMTS_AWARE - avoids the per-element
+        // closure call and dynamic instanceof on this hot traversal path; subclass semantics kept
+        return match (true) {
+            $node instanceof Block,
+            $node instanceof Closure,
+            $node instanceof Case_,
+            $node instanceof Catch_,
+            $node instanceof ClassMethod,
+            $node instanceof Do_,
+            $node instanceof Else_,
+            $node instanceof ElseIf_,
+            $node instanceof Finally_,
+            $node instanceof For_,
+            $node instanceof Foreach_,
+            $node instanceof Function_,
+            $node instanceof If_,
+            $node instanceof Namespace_,
+            $node instanceof TryCatch,
+            $node instanceof While_,
+            $node instanceof FileNode,
+            $node instanceof Declare_ => true,
+            default => false,
+        };
     }
 }