%% -*- erlang-indent-level: 2 -*-
%%
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%%
%% Copyright Ericsson AB 2001-2016. All Rights Reserved.
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%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
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%% http://www.apache.org/licenses/LICENSE-2.0
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%% ===========================================================================
%% Copyright (c) 2001 by Erik Johansson. All Rights Reserved
%% Time-stamp: <2008-04-20 14:54:00 richard>
%% ===========================================================================
%% Module : hipe_temp_map
%% Purpose :
%% Notes :
%% History : * 2001-07-24 Erik Johansson ([email protected]): Created.
%% ===========================================================================
%% Exports :
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-module(hipe_temp_map).
-export([cols2tuple/2, find/2, is_spilled/2, to_substlist/1]).
-include("../main/hipe.hrl").
%%----------------------------------------------------------------------------
%% Convert a list of [{R0, C1}, {R1, C2}, ...] to a temp_map
%% (Currently implemented as a tuple) tuple {C1, C2, ...}.
%%
%% The indices (Ri) must be unique but do not have to be sorted and
%% they can be sparse.
%% Note that the first allowed index is 0 -- this will be mapped to
%% element 1
%%----------------------------------------------------------------------------
-spec cols2tuple(hipe_map(), atom()) -> hipe_temp_map().
cols2tuple(Map, Target) ->
SortedMap = lists:keysort(1, Map),
cols2tuple(0, SortedMap, [], Target).
%% sorted_cols2tuple(Map, Target) ->
%% ?ASSERT(Map =:= lists:keysort(1, Map)),
%% cols2tuple(0, Map, [], Target).
%% Build a dense mapping
cols2tuple(_, [], Vs, _) ->
%% Done reverse the list and convert to tuple.
list_to_tuple(lists:reverse(Vs));
cols2tuple(N, [{R, C}|Ms], Vs, Target) when N =:= R ->
%% N makes sure the mapping is dense. N is he next key.
cols2tuple(N+1, Ms, [C|Vs], Target);
cols2tuple(N, SourceMapping=[{R,_}|_], Vs, Target) when N < R ->
%% The source was sparse, make up some placeholders...
Val =
case Target:is_precoloured(N) of
%% If it is precoloured, we know what to map it to.
true -> {reg, N};
false -> unknown
end,
cols2tuple(N+1, SourceMapping, [Val|Vs], Target).
%%
%% True if temp Temp is spilled.
%%
-spec is_spilled(non_neg_integer(), hipe_temp_map()) -> boolean().
is_spilled(Temp, Map) ->
case find(Temp, Map) of
{reg, _R} -> false;
{fp_reg, _R}-> false;
{spill, _N} -> true;
unknown -> false
end.
%% %% True if temp Temp is allocated to a reg.
%% in_reg(Temp, Map) ->
%% case element(Temp+1, Map) of
%% {reg, _R} -> true;
%% {fp_reg, _R}-> false;
%% {spill, _N} -> false;
%% unknown -> false
%% end.
%%
%% %% True if temp Temp is allocated to a fp_reg.
%% in_fp_reg(Temp, Map) ->
%% case element(Temp+1, Map) of
%% {fp_reg, _R} -> true;
%% {reg, _R} -> false;
%% {spill, _N} -> false;
%% unknown -> false
%% end.
%% Returns the inf temp Temp is mapped to.
find(Temp, Map) when Temp < tuple_size(Map) -> element(Temp+1, Map);
find(_, Map) when is_tuple(Map) -> unknown. % consistency with cols2tuple/2
%%
%% Converts a temp_map tuple back to a (sorted) key-list.
%%
-spec to_substlist(hipe_temp_map()) -> hipe_map().
to_substlist(Map) ->
T = tuple_to_list(Map),
mapping(T, 0).
mapping([R|Rs], Temp) ->
[{Temp, R}| mapping(Rs, Temp+1)];
mapping([], _) ->
[].
