From 46b5dbd7ce05841d37b009c2d35004c147f44934 Mon Sep 17 00:00:00 2001
From: Garret Rieger <grieger@google.com>
Date: Thu, 18 Aug 2022 01:18:16 +0000
Subject: [PATCH] [repacker] optimize index_for_offset.

---
 src/graph/graph.hh | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/graph/graph.hh b/src/graph/graph.hh
index 4a036af87..ab95a71c4 100644
--- a/src/graph/graph.hh
+++ b/src/graph/graph.hh
@@ -521,8 +521,11 @@ struct graph_t
     const auto& node = object (node_idx);
     if (offset < node.head || offset >= node.tail) return -1;
 
-    for (const auto& link : node.real_links)
+    unsigned length = node.real_links.length;
+    for (unsigned i = 0; i < length; i++)
     {
+      // Use direct access for increased performance, this is a hot method.
+      const auto& link = node.real_links.arrayZ[i];
       if (offset != node.head + link.position)
         continue;
       return link.objidx;