From 0247c6a09d5c97cae80d3d98543b6be39d0111a5 Mon Sep 17 00:00:00 2001
From: Michael Woerister <michaelwoerister@posteo>
Date: Tue, 25 Oct 2022 11:13:29 +0200
Subject: [PATCH] Experiment: Don't merge vtables.

---
 compiler/rustc_codegen_llvm/src/consts.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/compiler/rustc_codegen_llvm/src/consts.rs b/compiler/rustc_codegen_llvm/src/consts.rs
index dd3c43ba5ca7c..9c69c358f33f6 100644
--- a/compiler/rustc_codegen_llvm/src/consts.rs
+++ b/compiler/rustc_codegen_llvm/src/consts.rs
@@ -241,7 +241,14 @@ impl<'ll> CodegenCx<'ll, '_> {
             };
             llvm::LLVMSetInitializer(gv, cv);
             set_global_alignment(self, gv, align);
-            llvm::SetUnnamedAddress(gv, llvm::UnnamedAddr::Global);
+
+            // Experiment: What's the impact of making vtables unmergable?
+            if kind == Some("vtable") {
+                llvm::SetUnnamedAddress(gv, llvm::UnnamedAddr::No);
+            } else {
+                llvm::SetUnnamedAddress(gv, llvm::UnnamedAddr::Global);
+            }
+
             gv
         }
     }