From 7b9ff9b77dc6c788f8c23c9d791ceade5a25ead4 Mon Sep 17 00:00:00 2001
From: LlamaLad7 <l3gomindstorms@gmail.com>
Date: Mon, 17 Feb 2025 12:55:11 +0000
Subject: [PATCH] Avoid unnecessary linked list traversals in MethodLinker.
 (#133)

The chains themselves are assumed to be an implementation detail of this class, in which case it's fine to flatten them at any time.
---
 .../java/proguard/classfile/util/MethodLinker.java   | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/base/src/main/java/proguard/classfile/util/MethodLinker.java b/base/src/main/java/proguard/classfile/util/MethodLinker.java
index 89bd70def..9cfec7962 100644
--- a/base/src/main/java/proguard/classfile/util/MethodLinker.java
+++ b/base/src/main/java/proguard/classfile/util/MethodLinker.java
@@ -19,7 +19,9 @@
 
 import static proguard.classfile.instruction.Instruction.OP_INVOKESTATIC;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import proguard.classfile.AccessConstants;
 import proguard.classfile.Clazz;
@@ -132,12 +134,19 @@ private static void link(Member member1, Member member2) {
    * @return The last method in the linked list.
    */
   public static Member lastMember(Member member) {
+    List<Member> chain = new ArrayList<>();
     Member lastMember = member;
     while (lastMember.getProcessingInfo() != null
         && lastMember.getProcessingInfo() instanceof Member) {
+      chain.add(lastMember);
       lastMember = (Member) lastMember.getProcessingInfo();
     }
 
+    // Point every member in the chain directly to the last element to save time in the future
+    for (Member relatedMember : chain) {
+      relatedMember.setProcessingInfo(lastMember);
+    }
+
     return lastMember;
   }
 
@@ -149,6 +158,9 @@ public static Member lastMember(Member member) {
    */
   public static Processable lastProcessable(Processable processable) {
     Processable lastProcessable = processable;
+    if (lastProcessable instanceof Member) {
+      lastProcessable = lastMember((Member) lastProcessable);
+    }
     while (lastProcessable.getProcessingInfo() != null
         && lastProcessable.getProcessingInfo() instanceof Processable) {
       lastProcessable = (Processable) lastProcessable.getProcessingInfo();