%% -*- 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.
-module(hipe_ppc_ra_postconditions_fp).
-export([check_and_rewrite/2]).
-include("hipe_ppc.hrl").
check_and_rewrite(CFG, Coloring) ->
TempMap = hipe_temp_map:cols2tuple(Coloring, hipe_ppc_specific_fp, no_context),
do_bbs(hipe_ppc_cfg:labels(CFG), TempMap, CFG, false).
do_bbs([], _TempMap, CFG, DidSpill) -> {CFG, DidSpill};
do_bbs([Lbl|Lbls], TempMap, CFG0, DidSpill0) ->
Code0 = hipe_bb:code(BB = hipe_ppc_cfg:bb(CFG0, Lbl)),
{Code, DidSpill} = do_insns(Code0, TempMap, [], DidSpill0),
CFG = hipe_ppc_cfg:bb_add(CFG0, Lbl, hipe_bb:code_update(BB, Code)),
do_bbs(Lbls, TempMap, CFG, DidSpill).
do_insns([I|Insns], TempMap, Accum, DidSpill0) ->
{NewIs, DidSpill1} = do_insn(I, TempMap),
do_insns(Insns, TempMap, lists:reverse(NewIs, Accum), DidSpill0 or DidSpill1);
do_insns([], _TempMap, Accum, DidSpill) ->
{lists:reverse(Accum), DidSpill}.
do_insn(I, TempMap) ->
case I of
#lfd{} -> do_lfd(I, TempMap);
#lfdx{} -> do_lfdx(I, TempMap);
#stfd{} -> do_stfd(I, TempMap);
#stfdx{} -> do_stfdx(I, TempMap);
#fp_binary{} -> do_fp_binary(I, TempMap);
#fp_unary{} -> do_fp_unary(I, TempMap);
#pseudo_fmove{} -> do_pseudo_fmove(I, TempMap);
#pseudo_spill_fmove{} -> do_pseudo_spill_fmove(I, TempMap);
_ -> {[I], false}
end.
%%% Fix relevant instruction types.
do_lfd(I=#lfd{dst=Dst}, TempMap) ->
{FixDst, NewDst, DidSpill} = fix_dst(Dst, TempMap),
NewI = I#lfd{dst=NewDst},
{[NewI | FixDst], DidSpill}.
do_lfdx(I=#lfdx{dst=Dst}, TempMap) ->
{FixDst, NewDst, DidSpill} = fix_dst(Dst, TempMap),
NewI = I#lfdx{dst=NewDst},
{[NewI | FixDst], DidSpill}.
do_stfd(I=#stfd{src=Src}, TempMap) ->
{FixSrc, NewSrc, DidSpill} = fix_src(Src, TempMap),
NewI = I#stfd{src=NewSrc},
{FixSrc ++ [NewI], DidSpill}.
do_stfdx(I=#stfdx{src=Src}, TempMap) ->
{FixSrc, NewSrc, DidSpill} = fix_src(Src, TempMap),
NewI = I#stfdx{src=NewSrc},
{FixSrc ++ [NewI], DidSpill}.
do_fp_binary(I=#fp_binary{dst=Dst,src1=Src1,src2=Src2}, TempMap) ->
{FixDst,NewDst,DidSpill1} = fix_dst(Dst, TempMap),
{FixSrc1,NewSrc1,DidSpill2} = fix_src(Src1, TempMap),
{FixSrc2,NewSrc2,DidSpill3} = fix_src(Src2, TempMap),
NewI = I#fp_binary{dst=NewDst,src1=NewSrc1,src2=NewSrc2},
{FixSrc1 ++ FixSrc2 ++ [NewI | FixDst], DidSpill1 or DidSpill2 or DidSpill3}.
do_fp_unary(I=#fp_unary{dst=Dst,src=Src}, TempMap) ->
{FixDst,NewDst,DidSpill1} = fix_dst(Dst, TempMap),
{FixSrc,NewSrc,DidSpill2} = fix_src(Src, TempMap),
NewI = I#fp_unary{dst=NewDst,src=NewSrc},
{FixSrc ++ [NewI | FixDst], DidSpill1 or DidSpill2}.
do_pseudo_fmove(I=#pseudo_fmove{dst=Dst,src=Src}, TempMap) ->
case temp_is_spilled(Src, TempMap)
andalso temp_is_spilled(Dst, TempMap)
of
true -> % Turn into pseudo_spill_fmove
Temp = clone(Src),
NewI = #pseudo_spill_fmove{dst=Dst,temp=Temp,src=Src},
{[NewI], true};
_ ->
{[I], false}
end.
do_pseudo_spill_fmove(I=#pseudo_spill_fmove{temp=Temp}, TempMap) ->
%% Temp is above the low water mark and must not have been spilled
false = temp_is_spilled(Temp, TempMap),
{[I], false}.
%%% Fix Dst and Src operands.
fix_src(Src, TempMap) ->
case temp_is_spilled(Src, TempMap) of
true ->
NewSrc = clone(Src),
{[hipe_ppc:mk_pseudo_fmove(NewSrc, Src)], NewSrc, true};
_ ->
{[], Src, false}
end.
fix_dst(Dst, TempMap) ->
case temp_is_spilled(Dst, TempMap) of
true ->
NewDst = clone(Dst),
{[hipe_ppc:mk_pseudo_fmove(Dst, NewDst)], NewDst, true};
_ ->
{[], Dst, false}
end.
%%% Check if an operand is a pseudo-temp.
temp_is_spilled(Temp, TempMap) ->
case hipe_ppc:temp_is_allocatable(Temp) of
true ->
Reg = hipe_ppc:temp_reg(Temp),
tuple_size(TempMap) > Reg andalso hipe_temp_map:is_spilled(Reg, TempMap);
false -> true
end.
%%% Create a new temp with the same type as an old one.
clone(Temp) ->
Type = hipe_ppc:temp_type(Temp), % XXX: always double?
hipe_ppc:mk_new_temp(Type).
