From ca90a97dc4c317499071b3f18ee865815ab07128 Mon Sep 17 00:00:00 2001
From: vsadov <8218165+VSadov@users.noreply.github.com>
Date: Tue, 16 Nov 2021 07:45:14 -0800
Subject: [PATCH] a few fixes

---
 src/coreclr/vm/amd64/JitHelpers_Fast.asm | 8 ++++++++
 src/coreclr/vm/amd64/jithelpers_fast.S   | 7 +++++++
 2 files changed, 15 insertions(+)

diff --git a/src/coreclr/vm/amd64/JitHelpers_Fast.asm b/src/coreclr/vm/amd64/JitHelpers_Fast.asm
index 4b2e5ec3521..467129b4dea 100644
--- a/src/coreclr/vm/amd64/JitHelpers_Fast.asm
+++ b/src/coreclr/vm/amd64/JitHelpers_Fast.asm
@@ -455,6 +455,14 @@ LEAF_ENTRY JIT_WriteBarrier, _TEXT
 
     ; this is expected to be rare.
     RecordEscape:
+
+        ; 4) check if the source is escaped
+        mov     rax, rdx
+        and     rax, 01FFFFFh
+        shr     rax, 3
+        bt      qword ptr [r8], rax
+        jb      AssignAndMarkCards            ; source is already escaped.
+
         ; save rcx, rdx, r8 and have enough stack for the callee
         push rcx
         push rdx
diff --git a/src/coreclr/vm/amd64/jithelpers_fast.S b/src/coreclr/vm/amd64/jithelpers_fast.S
index 52bf8e41b24..ba7597ec645 100644
--- a/src/coreclr/vm/amd64/jithelpers_fast.S
+++ b/src/coreclr/vm/amd64/jithelpers_fast.S
@@ -358,6 +358,13 @@ LEAF_ENTRY JIT_WriteBarrier, _TEXT
         ret
 
     // this is expected to be rare.
+    // 4) check if the source is escaped
+        mov     rax, rsi
+        and     rax, 0x1FFFFF
+        shr     rax, 3
+        bt      qword ptr [rdx], rax
+        jb      AssignAndMarkCards            // source is already escaped.
+
     RecordEscape:
         // save rdi, rsi, rdx and r10 (possibly preadjusted rsi)
         push rdi