%% -*- 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_arm_subst).
-export([insn_temps/2, insn_lbls/2]).
-include("hipe_arm.hrl").
%% These should be moved to hipe_arm and exported
-type temp() :: #arm_temp{}.
-type shiftop() :: lsl | lsr | asr | ror.
-type imm4() :: 0..15.
-type imm5() :: 0..31.
-type imm8() :: 0..255.
-type am1() :: {imm8(),imm4()}
| temp()
| {temp(), rrx}
| {temp(), shiftop(), imm5()}
| {temp(), shiftop(), temp()}.
-type am2() :: #am2{}.
-type am3() :: #am3{}.
-type arg() :: temp() | integer().
-type funv() :: #arm_mfa{} | #arm_prim{} | temp().
-type label() :: non_neg_integer().
-type insn() :: tuple(). % for now
-type subst_fun() :: fun((temp()) -> temp()).
%% @doc Maps over the temporaries in an instruction
-spec insn_temps(subst_fun(), insn()) -> insn().
insn_temps(T, I) ->
AM1 = fun(O) -> am1_temps(T, O) end,
AM2 = fun(O) -> am2_temps(T, O) end,
AM3 = fun(O) -> am3_temps(T, O) end,
Arg = fun(O) -> arg_temps(T, O) end,
case I of
#alu {dst=D,src=L,am1=R} -> I#alu{dst=T(D),src=T(L),am1=AM1(R)};
#cmp {src=L,am1=R} -> I#cmp {src=T(L),am1=AM1(R)};
#load {dst=D,am2=S} -> I#load {dst=T(D),am2=AM2(S)};
#ldrsb {dst=D,am3=S} -> I#ldrsb {dst=T(D),am3=AM3(S)};
#move {dst=D,am1=S} -> I#move {dst=T(D),am1=AM1(S)};
#pseudo_move{dst=D,src=S} -> I#pseudo_move {dst=T(D),src=T(S)};
#store {src=S,am2=D} -> I#store {src=T(S),am2=AM2(D)};
#b_label{} -> I;
#comment{} -> I;
#label{} -> I;
#pseudo_bc{} -> I;
#pseudo_blr{} -> I;
#pseudo_call{funv=F} -> I#pseudo_call{funv=funv_temps(T, F)};
#pseudo_call_prepare{} -> I;
#pseudo_li{dst=D} -> I#pseudo_li{dst=T(D)};
#pseudo_switch{jtab=J=#arm_temp{},index=Ix=#arm_temp{}} ->
I#pseudo_switch{jtab=T(J),index=T(Ix)};
#pseudo_tailcall{funv=F,stkargs=Stk} ->
I#pseudo_tailcall{funv=funv_temps(T,F),stkargs=lists:map(Arg,Stk)};
#pseudo_tailcall_prepare{} -> I;
#smull{dstlo=DL,dsthi=DH,src1=L,src2=R} ->
I#smull{dstlo=T(DL),dsthi=T(DH),src1=T(L),src2=T(R)}
end.
-spec am1_temps(subst_fun(), am1()) -> am1().
am1_temps(_SubstTemp, T={C,R}) when is_integer(C), is_integer(R) -> T;
am1_temps(SubstTemp, T=#arm_temp{}) -> SubstTemp(T);
am1_temps(SubstTemp, {T=#arm_temp{},rrx}) -> {SubstTemp(T),rrx};
am1_temps(SubstTemp, {A=#arm_temp{},Op,B=#arm_temp{}}) when is_atom(Op) ->
{SubstTemp(A),Op,SubstTemp(B)};
am1_temps(SubstTemp, {T=#arm_temp{},Op,I}) when is_atom(Op), is_integer(I) ->
{SubstTemp(T),Op,I}.
-spec am2_temps(subst_fun(), am2()) -> am2().
am2_temps(SubstTemp, T=#am2{src=A=#arm_temp{},offset=O0}) ->
O = case O0 of
_ when is_integer(O0) -> O0;
#arm_temp{} -> SubstTemp(O0);
{B=#arm_temp{},rrx} -> {SubstTemp(B),rrx};
{B=#arm_temp{},Op,I} when is_atom(Op), is_integer(I) ->
{SubstTemp(B),Op,I}
end,
T#am2{src=SubstTemp(A),offset=O}.
-spec am3_temps(subst_fun(), am3()) -> am3().
am3_temps(SubstTemp, T=#am3{src=A=#arm_temp{},offset=O0}) ->
O = case O0 of
_ when is_integer(O0) -> O0;
#arm_temp{} -> SubstTemp(O0)
end,
T#am3{src=SubstTemp(A),offset=O}.
-spec funv_temps(subst_fun(), funv()) -> funv().
funv_temps(_SubstTemp, M=#arm_mfa{}) -> M;
funv_temps(_SubstTemp, P=#arm_prim{}) -> P;
funv_temps(SubstTemp, T=#arm_temp{}) -> SubstTemp(T).
-spec arg_temps(subst_fun(), arg()) -> arg().
arg_temps(_SubstTemp, Imm) when is_integer(Imm) -> Imm;
arg_temps(SubstTemp, T=#arm_temp{}) -> SubstTemp(T).
-type lbl_subst_fun() :: fun((label()) -> label()).
%% @doc Maps over the branch targets in an instruction
-spec insn_lbls(lbl_subst_fun(), insn()) -> insn().
insn_lbls(SubstLbl, I) ->
case I of
#b_label{label=Label} ->
I#b_label{label=SubstLbl(Label)};
#pseudo_bc{true_label=T, false_label=F} ->
I#pseudo_bc{true_label=SubstLbl(T), false_label=SubstLbl(F)};
#pseudo_call{sdesc=Sdesc, contlab=Contlab} ->
I#pseudo_call{sdesc=sdesc_lbls(SubstLbl, Sdesc),
contlab=SubstLbl(Contlab)}
end.
sdesc_lbls(_SubstLbl, Sdesc=#arm_sdesc{exnlab=[]}) -> Sdesc;
sdesc_lbls(SubstLbl, Sdesc=#arm_sdesc{exnlab=Exnlab}) ->
Sdesc#arm_sdesc{exnlab=SubstLbl(Exnlab)}.