%%% -*- erlang-indent-level: 2 -*-
%%%
%%% %CopyrightBegin%
%%%
%%% Copyright Ericsson AB 2001-2013. All Rights Reserved.
%%%
%%% 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.
%%%
%%% %CopyrightEnd%
%%%
%%%----------------------------------------------------------------------
%%% File : hipe_reg_worklists.erl
%%% Author : Andreas Wallin <[email protected]>
%%% Purpose : Represents sets of nodes/temporaries that we are
%%% working on, such as simplify and spill sets.
%%% Created : 3 Feb 2000 by Andreas Wallin <[email protected]>
%%% Modified: Spring 2005 by NilsOla Linnermark <[email protected]>
%%% to suit the optimistic coalesching allocator
%%%----------------------------------------------------------------------
-module(hipe_reg_worklists).
-author(['Andreas Wallin', 'Thorild Selén']).
-export([new/5, % only used by optimistic allocator
new/6,
simplify/1,
spill/1,
freeze/1,
stack/1,
add_simplify/2,
add_freeze/2,
add_coalesced/2,
add_coalesced/3, % only used by optimistic allocator
add_spill/2,
push_stack/3,
remove_simplify/2,
remove_spill/2,
remove_freeze/2,
is_empty_simplify/1,
is_empty_spill/1,
is_empty_freeze/1,
member_freeze/2,
member_coalesced_to/2, % only used by optimistic allocator
member_stack_or_coalesced/2,
non_stacked_or_coalesced_nodes/2,
transfer_freeze_simplify/2,
transfer_freeze_spill/2
]).
-ifdef(DEBUG_PRINTOUTS).
-export([print_memberships/1]).
-endif.
-record(worklists,
{simplify, % Low-degree nodes (if coalescing non move-related)
stack, % Stack of removed low-degree nodes, with adjacency lists
membership, % Mapping from temp to which set it is in
coalesced_to, % if the node is coalesced to (only used by optimistic allocator)
spill, % Significant-degree nodes
freeze % Low-degree move-related nodes
}).
%%-ifndef(DEBUG).
%%-define(DEBUG,true).
%%-endif.
-include("../main/hipe.hrl").
%%%----------------------------------------------------------------------
%% Function: new
%%
%% Description: Constructor for worklists structure
%%
%% Parameters:
%% IG -- Interference graph
%% Target -- Target module name
%% CFG -- Target-specific CFG
%% Move_sets -- Move information
%% K -- Number of registers
%%
%% Returns:
%% A new worklists data structure
%%
%%%----------------------------------------------------------------------
new(IG, Target, CFG, K, No_temporaries) -> % only used by optimistic allocator
CoalescedTo = hipe_bifs:array(No_temporaries, 'none'),
init(initial(Target, CFG), K, IG, empty(No_temporaries, CoalescedTo)).
new(IG, Target, CFG, Move_sets, K, No_temporaries) ->
init(initial(Target, CFG), K, IG, Move_sets, empty(No_temporaries, [])).
initial(Target, CFG) ->
{Min_temporary, Max_temporary} = Target:var_range(CFG),
NonAlloc = Target:non_alloc(CFG),
non_precoloured(Target, Min_temporary, Max_temporary, [])
-- [Target:reg_nr(X) || X <- NonAlloc].
non_precoloured(Target, Current, Max_temporary, Initial) ->
if Current > Max_temporary ->
Initial;
true ->
NewInitial =
case Target:is_precoloured(Current) of
true -> Initial;
false -> [Current|Initial]
end,
non_precoloured(Target, Current+1, Max_temporary, NewInitial)
end.
%% construct an empty initialized worklists data structure
empty(No_temporaries, CoalescedTo) ->
#worklists{
membership = hipe_bifs:array(No_temporaries, 'none'),
coalesced_to = CoalescedTo, % only used by optimistic allocator
simplify = ordsets:new(),
stack = [],
spill = ordsets:new(),
freeze = ordsets:new()
}.
%% Selectors for worklists record
simplify(Worklists) -> Worklists#worklists.simplify.
spill(Worklists) -> Worklists#worklists.spill.
freeze(Worklists) -> Worklists#worklists.freeze.
stack(Worklists) -> Worklists#worklists.stack.
%% Updating worklists records
set_simplify(Simplify, Worklists) ->
Worklists#worklists{simplify = Simplify}.
set_spill(Spill, Worklists) ->
Worklists#worklists{spill = Spill}.
set_freeze(Freeze, Worklists) ->
Worklists#worklists{freeze = Freeze}.
%%----------------------------------------------------------------------
%% Function: init
%%
%% Description: Initializes worklists
%%
%% Parameters:
%% Initials -- Not precoloured temporaries
%% K -- Number of registers
%% IG -- Interference graph
%% Move_sets -- Move information
%% Worklists -- (Empty) worklists structure
%%
%% Returns:
%% Initialized worklists structure
%%
%%----------------------------------------------------------------------
init([], _, _, Worklists) -> Worklists;
init([Initial|Initials], K, IG, Worklists) ->
case hipe_ig:is_trivially_colourable(Initial, K, IG) of
false ->
New_worklists = add_spill(Initial, Worklists),
init(Initials, K, IG, New_worklists);
_ ->
New_worklists = add_simplify(Initial, Worklists),
init(Initials, K, IG, New_worklists)
end.
init([], _, _, _, Worklists) -> Worklists;
init([Initial|Initials], K, IG, Move_sets, Worklists) ->
case hipe_ig:is_trivially_colourable(Initial, K, IG) of
false ->
New_worklists = add_spill(Initial, Worklists),
init(Initials, K, IG, Move_sets, New_worklists);
_ ->
case hipe_moves:move_related(Initial, Move_sets) of
true ->
New_worklists = add_freeze(Initial, Worklists),
init(Initials, K, IG, Move_sets, New_worklists);
_ ->
New_worklists = add_simplify(Initial, Worklists),
init(Initials, K, IG, Move_sets, New_worklists)
end
end.
%%%----------------------------------------------------------------------
%% Function: is_empty
%%
%% Description: Tests if the selected worklist if empty or not.
%%
%% Parameters:
%% Worklists -- A worklists data structure
%%
%% Returns:
%% true -- If the worklist was empty
%% false -- otherwise
%%
%%%----------------------------------------------------------------------
is_empty_simplify(Worklists) ->
simplify(Worklists) =:= [].
is_empty_spill(Worklists) ->
spill(Worklists) =:= [].
is_empty_freeze(Worklists) ->
freeze(Worklists) =:= [].
%%%----------------------------------------------------------------------
%% Function: add
%%
%% Description: Adds one element to one of the worklists.
%%
%% Parameters:
%% Element -- An element you want to add to the
%% selected worklist. The element should
%% be a node/temporary.
%% Worklists -- A worklists data structure
%%
%% Returns:
%% An worklists data-structure that have Element in selected
%% worklist.
%%
%%%----------------------------------------------------------------------
add_coalesced(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'stack_or_coalesced'),
Worklists.
add_coalesced(From, To, Worklists) -> % only used by optimistic allocator
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, From, 'stack_or_coalesced'),
Coalesced_to = Worklists#worklists.coalesced_to,
hipe_bifs:array_update(Coalesced_to, To, 'coalesced_to'),
Worklists.
add_simplify(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'simplify'),
Simplify = ordsets:add_element(Element, simplify(Worklists)),
set_simplify(Simplify, Worklists).
add_spill(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'spill'),
Spill = ordsets:add_element(Element, spill(Worklists)),
set_spill(Spill, Worklists).
add_freeze(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'freeze'),
Freeze = ordsets:add_element(Element, freeze(Worklists)),
set_freeze(Freeze, Worklists).
push_stack(Node, AdjList, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Node, 'stack_or_coalesced'),
Stack = Worklists#worklists.stack,
Worklists#worklists{stack = [{Node,AdjList}|Stack]}.
%%%----------------------------------------------------------------------
%% Function: remove
%%
%% Description: Removes one element to one of the worklists.
%%
%% Parameters:
%% Element -- An element you want to remove from the
%% selected worklist. The element should
%% be a node/temporary.
%% Worklists -- A worklists data structure
%%
%% Returns:
%% A worklists data-structure that don't have Element in selected
%% worklist.
%%
%%%----------------------------------------------------------------------
remove_simplify(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'none'),
Simplify = ordsets:del_element(Element, simplify(Worklists)),
set_simplify(Simplify, Worklists).
remove_spill(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'none'),
Spill = ordsets:del_element(Element, spill(Worklists)),
set_spill(Spill, Worklists).
remove_freeze(Element, Worklists) ->
Membership = Worklists#worklists.membership,
hipe_bifs:array_update(Membership, Element, 'none'),
Freeze = ordsets:del_element(Element, freeze(Worklists)),
set_freeze(Freeze, Worklists).
%%%----------------------------------------------------------------------
%% Function: transfer
%%
%% Description: Moves element from one worklist to another.
%%
%%%----------------------------------------------------------------------
transfer_freeze_simplify(Element, Worklists) ->
add_simplify(Element, remove_freeze(Element, Worklists)).
transfer_freeze_spill(Element, Worklists) ->
add_spill(Element, remove_freeze(Element, Worklists)).
%%%----------------------------------------------------------------------
%% Function: member
%%
%% Description: Checks if one element if member of selected worklist.
%%
%% Parameters:
%% Element -- Element you want to know if it's a
%% member of selected worklist.
%% Worklists -- A worklists data structure
%%
%% Returns:
%% true -- if Element is a member of selected worklist
%% false -- Otherwise
%%
%%%----------------------------------------------------------------------
member_coalesced_to(Element, Worklists) -> % only used by optimistic allocator
hipe_bifs:array_sub(Worklists#worklists.coalesced_to, Element) =:= 'coalesced_to'.
member_freeze(Element, Worklists) ->
hipe_bifs:array_sub(Worklists#worklists.membership, Element) =:= 'freeze'.
member_stack_or_coalesced(Element, Worklists) ->
hipe_bifs:array_sub(Worklists#worklists.membership, Element) =:= 'stack_or_coalesced'.
non_stacked_or_coalesced_nodes(Nodes, Worklists) ->
Membership = Worklists#worklists.membership,
[Node || Node <- Nodes,
hipe_bifs:array_sub(Membership, Node) =/= 'stack_or_coalesced'].
%%%----------------------------------------------------------------------
%% Print functions - only used for debugging
-ifdef(DEBUG_PRINTOUTS).
print_memberships(Worklists) ->
?debug_msg("Worklist memeberships:\n", []),
Membership = Worklists#worklists.membership,
NrElems = hipe_bifs:array_length(Membership),
Coalesced_to = Worklists#worklists.coalesced_to,
print_membership(NrElems, Membership, Coalesced_to).
print_membership(0, _, _) ->
true;
print_membership(Element, Membership, Coalesced_to) ->
NextElement = Element - 1,
?debug_msg("worklist ~w ~w ~w\n",
[NextElement, hipe_bifs:array_sub(Membership, NextElement),
hipe_bifs:array_sub(Coalesced_to, NextElement)]),
print_membership(NextElement, Membership, Coalesced_to).
-endif.
