diff --git a/library/compiler/x86/alien.factor b/library/compiler/x86/alien.factor
index d97ca67f4a..183106dba0 100644
--- a/library/compiler/x86/alien.factor
+++ b/library/compiler/x86/alien.factor
@@ -31,10 +31,6 @@ M: %unbox generate-node
     drop 2 input f compile-c-call  1 input push-return-reg ;
 
 : struct-ptr/size ( func -- )
-    ! Increase stack size
-    ESP 2 input SUB
-    ! Save destination address in EAX
-    EAX ESP MOV
     ! Load struct size
     2 input PUSH
     ! Load destination address
@@ -46,9 +42,17 @@ M: %unbox generate-node
     ECX POP ;
 
 M: %unbox-struct generate-node ( vop -- )
-    drop "unbox_value_struct" struct-ptr/size ;
+    drop
+    ! Increase stack size
+    ESP 2 input SUB
+    ! Save destination address in EAX
+    EAX ESP MOV
+    "unbox_value_struct" struct-ptr/size ;
 
 M: %box-struct generate-node ( vop -- )
+    ! Compute source address in EAX
+    EAX ESP MOV
+    EAX 4 ADD
     drop "box_value_struct" struct-ptr/size ;
 
 M: %box generate-node
diff --git a/library/compiler/x86/slots.factor b/library/compiler/x86/slots.factor
index 7f468f7c9c..a2fae93bcd 100644
--- a/library/compiler/x86/slots.factor
+++ b/library/compiler/x86/slots.factor
@@ -22,14 +22,8 @@ M: %write-barrier generate-node ( vop -- )
     #! Mark the card pointed to by vreg.
     drop
     0 input-operand card-bits SHR
-    0 scratch card-offset MOV rel-absolute-cell rel-cards
-    0 scratch 0 input-operand ADD
-    0 scratch [] card-mark OR ;
-
-!    drop
-!    0 input-operand card-bits SHR
-!    0 input-operand card-offset [+] card-mark OR
-!    rel-absolute-cell rel-cards ;
+    0 input-operand card-offset ADD rel-absolute-cell rel-cards
+    0 input-operand [] card-mark OR ;
 
 M: %set-slot generate-node ( vop -- )
     drop