From c6cb0acd3cedfb36325501b9a12f4086449fe520 Mon Sep 17 00:00:00 2001
From: embeddedt <42941056+embeddedt@users.noreply.github.com>
Date: Wed, 5 Jul 2023 20:01:43 -0400
Subject: [PATCH] Rewrite clear_mixin_classinfo, now more aggressive

---
 .../modernfix/util/ClassInfoManager.java      | 71 +++++++++++++++----
 1 file changed, 57 insertions(+), 14 deletions(-)

diff --git a/common/src/main/java/org/embeddedt/modernfix/util/ClassInfoManager.java b/common/src/main/java/org/embeddedt/modernfix/util/ClassInfoManager.java
index 5ee5cd77..2f458dca 100644
--- a/common/src/main/java/org/embeddedt/modernfix/util/ClassInfoManager.java
+++ b/common/src/main/java/org/embeddedt/modernfix/util/ClassInfoManager.java
@@ -1,30 +1,73 @@
 package org.embeddedt.modernfix.util;
 
+import org.embeddedt.modernfix.ModernFix;
 import org.embeddedt.modernfix.core.ModernFixMixinPlugin;
+import org.objectweb.asm.tree.ClassNode;
+import org.spongepowered.asm.mixin.MixinEnvironment;
+import org.spongepowered.asm.mixin.extensibility.IMixinInfo;
 import org.spongepowered.asm.mixin.transformer.ClassInfo;
 
 import java.lang.reflect.Field;
+import java.util.Collection;
 import java.util.Map;
 
 public class ClassInfoManager {
-    private static Map<String, ClassInfo> classInfoCache = null;
+    private static boolean hasRun = false;
     public static void clear() {
-        if(!ModernFixMixinPlugin.instance.isOptionEnabled("perf.clear_mixin_classinfo.ClassInfoManager"))
+        if (!ModernFixMixinPlugin.instance.isOptionEnabled("perf.clear_mixin_classinfo.ClassInfoManager") || hasRun)
             return;
-        if(classInfoCache == null) {
-            try {
-                Field field = ClassInfo.class.getDeclaredField("cache");
-                field.setAccessible(true);
-                classInfoCache = (Map<String, ClassInfo>)field.get(null);
-            } catch(ReflectiveOperationException | RuntimeException e) {
-                e.printStackTrace();
-                return;
-            }
-        }
+        hasRun = true;
+        ModernFix.resourceReloadExecutor().execute(ClassInfoManager::doClear);
+    }
+
+    private static Field accessible(Field f) {
+        f.setAccessible(true);
+        return f;
+    }
+
+    private static void doClear() {
+        Map<String, ClassInfo> classInfoCache;
+        Field mixinField, stateField, classNodeField, methodsField, fieldsField;
+        Class<?> stateClz;
         try {
-            classInfoCache.entrySet().removeIf(entry -> !entry.getKey().equals("java/lang/Object") && (entry.getValue() == null || !entry.getValue().isMixin()));
-        } catch(RuntimeException e) {
+            Field field = accessible(ClassInfo.class.getDeclaredField("cache"));
+            classInfoCache = (Map<String, ClassInfo>) field.get(null);
+            mixinField = accessible(ClassInfo.class.getDeclaredField("mixin"));
+            methodsField = accessible(ClassInfo.class.getDeclaredField("methods"));
+            fieldsField = accessible(ClassInfo.class.getDeclaredField("fields"));
+            stateClz = Class.forName("org.spongepowered.asm.mixin.transformer.MixinInfo$State");
+            stateField = accessible(Class.forName("org.spongepowered.asm.mixin.transformer.MixinInfo").getDeclaredField("state"));
+            classNodeField = accessible(stateClz.getDeclaredField("classNode"));
+        } catch (ReflectiveOperationException | RuntimeException e) {
+            e.printStackTrace();
+            return;
+        }
+        MixinEnvironment.getDefaultEnvironment().audit();
+        try {
+            ClassNode emptyNode = new ClassNode();
+            classInfoCache.entrySet().removeIf(entry -> {
+                if(entry.getKey().equals("java/lang/Object"))
+                    return false;
+                ClassInfo mixinClz = entry.getValue();
+                try {
+                    if(mixinClz.isMixin()) {
+                        // clear classNode in MixinInfo.State
+                        IMixinInfo theInfo = (IMixinInfo) mixinField.get(mixinClz);
+                        Object state = stateField.get(theInfo);
+                        if (state != null)
+                            classNodeField.set(state, emptyNode);
+                    }
+                    // clear fields, methods
+                    ((Collection<?>)methodsField.get(mixinClz)).clear();
+                    ((Collection<?>)fieldsField.get(mixinClz)).clear();
+                } catch (ReflectiveOperationException | RuntimeException e) {
+                    e.printStackTrace();
+                }
+                return true;
+            });
+        } catch (RuntimeException e) {
             e.printStackTrace();
         }
+        ModernFix.LOGGER.warn("Cleared mixin data structures");
     }
 }