%% -*- 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_gensym.erl
%% Author : Eric Johansson and Kostis Sagonas
%% Description : Generates unique symbols and fresh integer counts.
%%=======================================================================
%% $Id$
%%=======================================================================
%% Notes: Written while we were in Montreal, Canada for PPDP-2000 as an
%% exercise in Principles and Practice of Declarative Programming!
%%=======================================================================
-module(hipe_gensym).
-export([%% init/0, new_var/0, new_label/0,
%% update_lblrange/1, update_vrange/1, var_range/0, label_range/0,
set_var/1, get_var/0, get_next_var/0,
set_label/1, get_label/0, get_next_label/0]).
-export([init/1, new_var/1, new_label/1,
update_vrange/2, update_lblrange/2, var_range/1, label_range/1,
set_var_range/3, set_label_range/3,
set_var/2, get_var/1, get_next_var/1,
set_label/2, get_label/1, get_next_label/1]).
%%-----------------------------------------------------------------------
%% Types of allowable entities to set global variables for
%%-----------------------------------------------------------------------
-type gvarname() :: 'icode' | 'rtl' | 'arm' | 'ppc' | 'sparc' | 'x86' | 'llvm'.
%%-----------------------------------------------------------------------
%% init() ->
%% put(var_count, 0),
%% put(label_count, 0),
%% put(var_min, 0),
%% put(var_max, 0),
%% put(lbl_min, 1),
%% put(lbl_max, 1),
%% ok.
-spec init(gvarname()) -> 'ok'.
init(What) ->
put({What,var_count}, 0),
put({What,label_count}, 0),
put({What,var_min}, 0),
put({What,var_max}, 0),
put({What,lbl_min}, 1),
put({What,lbl_max}, 1),
ok.
%% new_var() ->
%% V = get(var_count),
%% put(var_count, V+1),
%% V.
-spec new_var(gvarname()) -> non_neg_integer().
new_var(What) ->
T = {What, var_count},
V = get(T),
put(T, V+1),
V.
%% new_label() ->
%% L = get(label_count),
%% put(label_count, L+1),
%% L.
-spec new_label(gvarname()) -> non_neg_integer().
new_label(What) ->
T = {What, label_count},
L = get(T),
put(T, L+1),
L.
%% update_vrange(V) ->
%% Vmax = get(var_max),
%% Vmin = get(var_min),
%% put(var_min, erlang:min(V, Vmin)),
%% put(var_max, erlang:max(V, Vmax)),
%% ok.
-spec update_vrange(gvarname(), non_neg_integer()) -> 'ok'.
update_vrange(What, V) ->
Tmin = {What, var_min},
Tmax = {What, var_max},
Vmax = get(Tmax),
Vmin = get(Tmin),
put(Tmin, erlang:min(V, Vmin)),
put(Tmax, erlang:max(V, Vmax)),
ok.
%% update_lblrange(L) ->
%% Lmax = get(lbl_max),
%% Lmin = get(lbl_min),
%% put(lbl_min, erlang:min(L, Lmin)),
%% put(lbl_max, erlang:max(L, Lmax)),
%% ok.
-spec update_lblrange(gvarname(), non_neg_integer()) -> 'ok'.
update_lblrange(What, L) ->
Tmin = {What, lbl_min},
Tmax = {What, lbl_max},
Lmax = get(Tmax),
Lmin = get(Tmin),
put(Tmin, erlang:min(L, Lmin)),
put(Tmax, erlang:max(L, Lmax)),
ok.
%% var_range() ->
%% {get(var_min), get(var_max)}.
-spec var_range(gvarname()) -> {non_neg_integer(), non_neg_integer()}.
var_range(What) ->
{get({What,var_min}), get({What,var_max})}.
-spec set_var_range(gvarname(), non_neg_integer(), non_neg_integer()) -> 'ok'.
set_var_range(What, Min, Max) ->
put({What,var_min}, Min),
put({What,var_max}, Max),
ok.
%% label_range() ->
%% {get(lbl_min), get(lbl_max)}.
-spec label_range(gvarname()) -> {non_neg_integer(), non_neg_integer()}.
label_range(What) ->
{get({What,lbl_min}), get({What,lbl_max})}.
-spec set_label_range(gvarname(), non_neg_integer(), non_neg_integer()) -> 'ok'.
set_label_range(What, Min, Max) ->
put({What,lbl_min}, Min),
put({What,lbl_max}, Max),
ok.
%%-----------------------------------------------------------------------
%% Variable counter
%%-----------------------------------------------------------------------
-spec set_var(non_neg_integer()) -> 'ok'.
set_var(X) ->
put(var_max, X),
ok.
-spec set_var(gvarname(), non_neg_integer()) -> 'ok'.
set_var(What, X) ->
put({What,var_max}, X),
ok.
-spec get_var() -> non_neg_integer().
get_var() ->
get(var_max).
-spec get_var(gvarname()) -> non_neg_integer().
get_var(What) ->
get({What,var_max}).
-spec get_next_var() -> non_neg_integer().
get_next_var() ->
C = get(var_max),
put(var_max, C+1),
C+1.
-spec get_next_var(gvarname()) -> non_neg_integer().
get_next_var(What) ->
T = {What, var_max},
C = get(T),
put(T, C+1),
C+1.
%%-----------------------------------------------------------------------
%% Label counter
%%-----------------------------------------------------------------------
-spec set_label(non_neg_integer()) -> 'ok'.
set_label(X) ->
put(lbl_max, X),
ok.
-spec set_label(gvarname(), non_neg_integer()) -> 'ok'.
set_label(What, X) ->
put({What,lbl_max}, X),
ok.
-spec get_label() -> non_neg_integer().
get_label() ->
get(lbl_max).
-spec get_label(gvarname()) -> non_neg_integer().
get_label(What) ->
get({What,lbl_max}).
-spec get_next_label() -> non_neg_integer().
get_next_label() ->
C = get(lbl_max),
put(lbl_max, C+1),
C+1.
-spec get_next_label(gvarname()) -> non_neg_integer().
get_next_label(What) ->
T = {What, lbl_max},
C = get(T),
put(T, C+1),
C+1.
%%-----------------------------------------------------------------------
