From 5506951ffb1c5f4195c77c6b245fa4f8916dd257 Mon Sep 17 00:00:00 2001
From: Hendiadyoin1 <leon.a@serenityos.org>
Date: Tue, 21 Feb 2023 21:38:30 +0100
Subject: [PATCH] LibJS: Don't try to merge unterminated BasicBlocks

This was causing a Segfault, trying to access the non-present terminator
---
 Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp b/Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp
index fd3a19531c..cbbb27644f 100644
--- a/Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp
+++ b/Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp
@@ -30,6 +30,9 @@ void MergeBlocks::perform(PassPipelineExecutable& executable)
         if (executable.exported_blocks->contains(*entry.value.begin()))
             continue;
 
+        if (!entry.key->is_terminated())
+            continue;
+
         if (entry.key->terminator()->type() != Instruction::Type::Jump)
             continue;