%%% -*- erlang-indent-level: 2 -*-
%%%
%%% Licensed under the Apache License, Version 2.0 (the "License");
%%% you may not use this file except in compliance with the License.
%%% You may obtain a copy of the License at
%%%
%%% http://www.apache.org/licenses/LICENSE-2.0
%%%
%%% Unless required by applicable law or agreed to in writing, software
%%% distributed under the License is distributed on an "AS IS" BASIS,
%%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%%% See the License for the specific language governing permissions and
%%% limitations under the License.
%%%
%%%-------------------------------------------------------------------
%%% File : hipe_rtl_cleanup_const.erl
%%% Author : Tobias Lindahl <tobiasl@it.uu.se>
%%% Description :
%%%
%%% Created : 5 Mar 2004 by Tobias Lindahl <tobiasl@it.uu.se>
%%%-------------------------------------------------------------------
%% Big constants (floats, bignums) can be used as arguments to
%% arbitrary instructions in RTL. Since these are located in the
%% constants area and the only instruction that currently can access
%% them is load_address, the constants have to be moved out of the
%% instruction and loaded into temporary variables before the
%% instruction.
%%
%% Some backends can make use of the information that the arguments
%% are really constants. Here is the place to add new backend-specific
%% behaviour depending on this.
%%--------------------------------------------------------------------
-module(hipe_rtl_cleanup_const).
-export([cleanup/1]).
-include("hipe_rtl.hrl").
%%--------------------------------------------------------------------
%%-spec cleanup(#rtl{}) -> #rtl{}.
cleanup(Rtl) ->
Code = cleanup(hipe_rtl:rtl_code(Rtl), []),
hipe_rtl:rtl_code_update(Rtl, Code).
cleanup([I|Left], Acc) ->
Args = hipe_rtl:args(I),
case [X || X <- Args, hipe_rtl:is_const_label(X)] of
[] ->
cleanup(Left, [I|Acc]);
ConstArgs ->
NewIns = cleanup_instr(ConstArgs, I),
cleanup(Left, NewIns ++ Acc)
end;
cleanup([], Acc) ->
lists:reverse(Acc).
cleanup_instr(Consts, I) ->
cleanup_instr(ordsets:from_list(Consts), I, []).
cleanup_instr([Const|Left], I, Acc) ->
Dst = hipe_rtl:mk_new_var(),
ConstLabel = hipe_rtl:const_label_label(Const),
Load = hipe_rtl:mk_load_address(Dst, ConstLabel, constant),
case I of
X when is_record(X, fp_unop) orelse is_record(X, fp) ->
Fdst = hipe_rtl:mk_new_fpreg(),
Fconv = lists:flatten(hipe_tagscheme:unsafe_untag_float(Fdst, Dst)),
NewI = hipe_rtl:subst_uses([{Const, Fdst}], I),
cleanup_instr(Left, NewI, lists:reverse(Fconv, [Load|Acc]));
_ ->
NewI = hipe_rtl:subst_uses([{Const, Dst}], I),
cleanup_instr(Left, NewI, [Load|Acc])
end;
cleanup_instr([], I, Acc) ->
[I|Acc].