deob/src/main/java/dev/openrs2/deob/Deobfuscator.kt

@@ -28,6 +28,7 @@ import dev.openrs2.deob.transform.OriginalNameTransformer
 import dev.openrs2.deob.transform.OriginalPcRestoreTransformer
 import dev.openrs2.deob.transform.OriginalPcSaveTransformer
 import dev.openrs2.deob.transform.OverrideTransformer
+import dev.openrs2.deob.transform.RedundantGotoTransformer
 import dev.openrs2.deob.transform.RemapTransformer
 import dev.openrs2.deob.transform.ResetTransformer
 import dev.openrs2.deob.transform.StaticScramblingTransformer
@@ -180,6 +181,7 @@ class Deobfuscator(private val input: Path, private val output: Path) {
             VisibilityTransformer(),
             FinalTransformer(),
             OverrideTransformer(),
+            RedundantGotoTransformer(),
             OriginalPcRestoreTransformer(),
             FernflowerExceptionTransformer()
         )

deob/src/main/java/dev/openrs2/deob/transform/RedundantGotoTransformer.kt

@@ -0,0 +1,53 @@
+package dev.openrs2.deob.transform
+
+import com.github.michaelbull.logging.InlineLogger
+import dev.openrs2.asm.classpath.ClassPath
+import dev.openrs2.asm.classpath.Library
+import dev.openrs2.asm.nextReal
+import dev.openrs2.asm.removeDeadCode
+import dev.openrs2.asm.transform.Transformer
+import org.objectweb.asm.Opcodes
+import org.objectweb.asm.tree.ClassNode
+import org.objectweb.asm.tree.JumpInsnNode
+import org.objectweb.asm.tree.MethodNode
+
+class RedundantGotoTransformer : Transformer() {
+    private var removed = 0
+
+    override fun preTransform(classPath: ClassPath) {
+        removed = 0
+    }
+
+    override fun preTransformMethod(
+        classPath: ClassPath,
+        library: Library,
+        clazz: ClassNode,
+        method: MethodNode
+    ): Boolean {
+        method.removeDeadCode(clazz.name)
+        return false
+    }
+
+    override fun transformCode(classPath: ClassPath, library: Library, clazz: ClassNode, method: MethodNode): Boolean {
+        for (instruction in method.instructions) {
+            if (instruction.opcode == Opcodes.GOTO) {
+                instruction as JumpInsnNode
+
+                if (instruction.nextReal === instruction.label.nextReal) {
+                    method.instructions.remove(instruction)
+                    removed++
+                }
+            }
+        }
+
+        return false
+    }
+
+    override fun postTransform(classPath: ClassPath) {
+        logger.info { "Removed $removed redundant GOTO instructions" }
+    }
+
+    private companion object {
+        private val logger = InlineLogger()
+    }
+}