From 7f3ae69249546570fc2de6043e034542f73c1a73 Mon Sep 17 00:00:00 2001
From: SingleAccretion <62474226+SingleAccretion@users.noreply.github.com>
Date: Fri, 4 Mar 2022 01:59:13 +0300
Subject: [PATCH] Fix copy propagation (#66070)

Now that we don't push defs for shadowed parameters, we don't want to pop them as well.
---
 src/coreclr/jit/copyprop.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/coreclr/jit/copyprop.cpp b/src/coreclr/jit/copyprop.cpp
index 991c658..bfc6d04 100644
--- a/src/coreclr/jit/copyprop.cpp
+++ b/src/coreclr/jit/copyprop.cpp
@@ -43,11 +43,13 @@ void Compiler::optBlockCopyPropPopStacks(BasicBlock* block, LclNumToLiveDefsMap*
                 }
 
                 CopyPropSsaDefStack* stack = nullptr;
-                curSsaName->Lookup(lclNum, &stack);
-                stack->Pop();
-                if (stack->Empty())
+                if (curSsaName->Lookup(lclNum, &stack))
                 {
-                    curSsaName->Remove(lclNum);
+                    stack->Pop();
+                    if (stack->Empty())
+                    {
+                        curSsaName->Remove(lclNum);
+                    }
                 }
             }
         }
-- 
2.7.4