diff --git a/basis/cpu/architecture/architecture.factor b/basis/cpu/architecture/architecture.factor
index 1931187779..2d3f8a8b40 100644
--- a/basis/cpu/architecture/architecture.factor
+++ b/basis/cpu/architecture/architecture.factor
@@ -43,7 +43,7 @@ GENERIC# load-literal 1 ( obj reg -- )
 
 HOOK: load-indirect cpu ( obj reg -- )
 
-HOOK: stack-frame-size cpu ( frame-size -- n )
+HOOK: stack-frame-size cpu ( stack-frame -- n )
 
 ! Set up caller stack frame
 HOOK: %prologue cpu ( n -- )
@@ -197,3 +197,12 @@ HOOK: %write-barrier cpu ( src card# table -- )
 
 ! GC check
 HOOK: %gc cpu ( -- )
+
+! Spilling
+HOOK: %spill-integer cpu ( src n -- )
+
+HOOK: %spill-float cpu ( src n -- )
+
+HOOK: %reload-integer cpu ( dst n -- )
+
+HOOK: %reload-float cpu ( dst n -- )
diff --git a/basis/cpu/x86/32/32.factor b/basis/cpu/x86/32/32.factor
index a170878eec..e7e654c8f7 100644
--- a/basis/cpu/x86/32/32.factor
+++ b/basis/cpu/x86/32/32.factor
@@ -267,7 +267,10 @@ M: x86.32 %callback-return ( n -- )
     #! b) If the callback is returning a large struct, we have
     #! to fix ESP.
     {
-        { [ dup abi>> "stdcall" = ] [ <alien-stack-frame> size>> ] }
+        { [ dup abi>> "stdcall" = ] [
+            <alien-stack-frame>
+            [ params>> ] [ return>> ] bi +
+        ] }
         { [ dup return>> large-struct? ] [ drop 4 ] }
         [ drop 0 ]
     } cond RET ;
diff --git a/basis/cpu/x86/architecture/architecture.factor b/basis/cpu/x86/architecture/architecture.factor
index 83876d72f8..bfcb79d41d 100644
--- a/basis/cpu/x86/architecture/architecture.factor
+++ b/basis/cpu/x86/architecture/architecture.factor
@@ -1,10 +1,11 @@
 ! Copyright (C) 2005, 2008 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: accessors alien alien.c-types arrays cpu.x86.assembler
-cpu.x86.assembler.private cpu.architecture kernel kernel.private
-math memory namespaces make sequences words system
-layouts combinators math.order locals compiler.constants
-compiler.cfg.registers compiler.cfg.instructions
+USING: accessors assocs alien alien.c-types arrays
+cpu.x86.assembler cpu.x86.assembler.private cpu.architecture
+kernel kernel.private math memory namespaces make sequences
+words system layouts combinators math.order locals
+compiler.constants compiler.cfg.registers
+compiler.cfg.instructions compiler.codegen
 compiler.codegen.fixup ;
 IN: cpu.x86.architecture
 
@@ -14,6 +15,13 @@ HOOK: stack-reg cpu ( -- reg )
 
 : stack@ ( n -- op ) stack-reg swap [+] ;
 
+: spill-integer@ ( n -- op )
+    cells stack-frame get [ params>> ] [ return>> ] bi + + stack@ ;
+
+: spill-float@ ( n -- op )
+    #! XXX
+    cells stack-frame get [ params>> ] [ return>> ] bi + + stack@ ;
+
 : next-stack@ ( n -- operand )
     #! nth parameter from the next stack frame. Used to box
     #! input values to callbacks; the callback has its own
@@ -60,8 +68,13 @@ M: fixnum load-literal
 : align-stack ( n -- n' )
     os macosx? cpu x86.64? or [ 16 align ] when ;
 
-M: x86 stack-frame-size ( n -- i )
-    3 cells + align-stack ;
+M: x86 stack-frame-size ( stack-frame -- i )
+    [ spill-counts>> [ swap reg-size * ] { } assoc>map sum ]
+    [ params>> ]
+    [ return>> ]
+    tri + +
+    3 cells +
+    align-stack ;
 
 : decr-stack-reg ( n -- )
     dup 0 = [ drop ] [ stack-reg swap SUB ] if ;
@@ -193,3 +206,9 @@ M: x86 %unbox-any-c-ptr ( dst src -- )
     rs-reg POP
     ! Restore ds-reg
     ds-reg POP ;
+
+M: x86 %spill-integer ( src n -- )
+    spill-integer@ swap MOV ;
+
+M: x86 %reload-integer ( dst n -- )
+    spill-integer@ MOV ;
diff --git a/basis/cpu/x86/sse2/sse2.factor b/basis/cpu/x86/sse2/sse2.factor
index 9650a4ce11..1f3090fcbd 100644
--- a/basis/cpu/x86/sse2/sse2.factor
+++ b/basis/cpu/x86/sse2/sse2.factor
@@ -8,6 +8,12 @@ compiler.cfg.registers compiler.cfg.builder cpu.architecture
 cpu.x86.assembler cpu.x86.architecture cpu.x86.intrinsics ;
 IN: cpu.x86.sse2
 
+M: x86 %spill-float ( src n -- )
+    spill-float@ swap MOVSD ;
+
+M: x86 %reload-float ( dst n -- )
+    spill-float@ MOVSD ;
+
 M: x86 %copy-float MOVSD ;
 
 M:: x86 %box-float ( dst src temp -- )