From aadea3f682423ec539a7e7718b28e7d9e6d67ee6 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sesse@chromium.org>
Date: Fri, 1 Nov 2024 15:58:35 +0100
Subject: [PATCH] Microoptimization in LoadDepsFromLog().

This cuts off another ~100 ms, most likely because the compiler
doesn't have smart enough alias analysis to do the same (trivial)
transformation.
---
 src/graph.cc | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/graph.cc b/src/graph.cc
index f04ffb47c8..c1276daefb 100644
--- a/src/graph.cc
+++ b/src/graph.cc
@@ -740,12 +740,13 @@ bool ImplicitDepLoader::LoadDepsFromLog(Edge* edge, string* err) {
     return false;
   }
 
-  vector<Node*>::iterator implicit_dep =
-      PreallocateSpace(edge, deps->node_count);
-  for (int i = 0; i < deps->node_count; ++i, ++implicit_dep) {
-    Node* node = deps->nodes[i];
-    *implicit_dep = node;
-    node->AddOutEdge(edge);
+  Node** nodes = deps->nodes;
+  size_t node_count = deps->node_count;
+  edge->inputs_.insert(edge->inputs_.end() - edge->order_only_deps_,
+                       nodes, nodes + node_count);
+  edge->implicit_deps_ += node_count;
+  for (size_t i = 0; i < node_count; ++i) {
+    nodes[i]->AddOutEdge(edge);
   }
   return true;
 }