From a5fb869640c0f35bd6b02e223ec03d7187a80c49 Mon Sep 17 00:00:00 2001
From: Sathya Gunasekaran <gsathya.ceg@gmail.com>
Date: Thu, 27 Oct 2022 16:43:34 +0100
Subject: [PATCH] [hir] Skip backedges when handling phis

These will be handled later during Environment.merge, no need to set an empty
Set as value.
---
 compiler/forget/src/HIR/InferReferenceEffects.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler/forget/src/HIR/InferReferenceEffects.ts b/compiler/forget/src/HIR/InferReferenceEffects.ts
index 34985dbaed..7b8a126f3a 100644
--- a/compiler/forget/src/HIR/InferReferenceEffects.ts
+++ b/compiler/forget/src/HIR/InferReferenceEffects.ts
@@ -410,7 +410,10 @@ class Environment {
         values.add(v);
       }
     }
-    this.#variables.set(phi.id.id, values);
+
+    if (values.size > 0) {
+      this.#variables.set(phi.id.id, values);
+    }
   }
 }