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diff --git a/lib/hipe/opt/hipe_spillmin.erl b/lib/hipe/opt/hipe_spillmin.erl
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+%% -*- erlang-indent-level: 2 -*-
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2005-2009. All Rights Reserved.
+%% 
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%% 
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%% 
+%% %CopyrightEnd%
+%%
+%% ==========================================================================
+%%  Module  :  hipe_spillmin
+%%  Purpose :  Driver module for minimizing the number of stack slots used
+%%	       by a function. This is done using an algorithm for register
+%%             allocation. The implementation is target-independent and
+%%             requires a target-specific interface module as argument.  
+%% 
+%% $Id$
+%% ==========================================================================
+%% Exported functions (short description):
+%%
+%%  stackalloc(CFG, StackSlots, SpillIndex, Options, Target, TempMap) -> 
+%%      {Coloring, NumberOfSpills}
+%%    Takes a CFG and the TempMap from register allocation and returns 
+%%    a coloring of stack slots.  
+%%    StackSlots should be a list of used stack slots, usually empty at
+%%    first call to function.
+%%    SpillIndex is the the first position we will spill to, usually 0.
+%%    TempMap is the TempMap from the register allocation
+%%
+%%    The Coloring will be in the form of the "allocation datastructure"
+%%    described below, that is, a list of tuples on the form
+%%      {Name, {spill, SpillIndex}}
+%%    The NumberOfSpills is either 0 indicating no spill or the 
+%%    SpillIndex of the last spilled register.
+%%
+%%  mapmerge(Map, SpillMap) -> NewMap
+%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-module(hipe_spillmin).
+-export([stackalloc/6, mapmerge/2]).
+
+%%-define(DEBUG, 1).
+-define(HIPE_INSTRUMENT_COMPILER, true).
+
+%%---------------------------------------------------------------------------
+
+-include("../main/hipe.hrl").
+-include("../flow/cfg.hrl").
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%
+%% stackalloc(CFG, StackSlots, SpillIndex, Options, Target, TempMap) 
+%%   Calculates an allocation of stack slots using either a linear scan
+%%   or a graph coloring allocation algorithm.
+%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec stackalloc(#cfg{}, [_], non_neg_integer(),
+		 comp_options(), module(), hipe_temp_map()) ->
+                                {hipe_spill_map(), non_neg_integer()}.
+ 
+stackalloc(CFG, StackSlots, SpillIndex, Options, Target, TempMap) ->
+  case proplists:get_bool(spillmin_color, Options) of
+    false ->
+      ?option_time(hipe_spillmin_scan:stackalloc(CFG, StackSlots, SpillIndex,
+						 Options, Target, TempMap),
+		   "Spill minimize, linear scan", Options);
+    true ->
+      ?option_time(hipe_spillmin_color:stackalloc(CFG, StackSlots, SpillIndex,
+						  Options, Target, TempMap),
+		   "Spill minimize, graph coloring", Options)
+  end.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% mapmerge(Map, SpillMap)
+%%
+%% stackalloc/6 will only return the subset of the tempmap that contains 
+%% the spilled temporaries. This function is used to merge the old 
+%% complete tempmap with the new spill information.
+%% Map is the old map (a list of [{R0, C1}, {R1, C2}, ...]).
+%% SpillMap is the new "spill" map.
+%% !! Warning, the function does not work with the maps in another order !! 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Combines the map with allocated spills with a map from the register
+%% allocator
+
+-spec mapmerge(hipe_map(), hipe_spill_map()) -> hipe_map().
+
+mapmerge(TempMap, SpillMap) ->
+  mapmerge(TempMap, SpillMap, []).
+
+mapmerge([], _, Ack) ->
+  lists:reverse(Ack);
+mapmerge([{T1, _}|T1s], [{T2, C}|T2s], Ack) when T1 =:= T2 -> 
+  mapmerge(T1s, T2s, [{T1, C}|Ack]);
+mapmerge([{_, unknown}|T1s], T2s, Ack) ->
+  mapmerge(T1s, T2s, Ack);
+mapmerge([T1|T1s], T2s, Ack) -> 
+  mapmerge(T1s, T2s, [T1|Ack]).