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1c65d003f7
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Branches: main
Add the shorthand_goal_expr wrapper type to ease hlds->hlds transformations.
compiler/hlds_goal.m
Create a new type, the `shorthand_goal_expr', for goals kinds that
are implemented by a (ordinary_hlds + shorthand) -> (ordinary_hlds)
transformation. At present, bi_implication is the only kind of
of goal that is implemented in this way.
Moved bi_implication functor from the type goal_expr to the new
shorthand_goal_expr type.
Added the functor shorthand to the goal_expr type.
compiler/*.m
Change switches on hlds_goal_expr that call error when they recognise
`bi_implication' from calling error when they recognise
`bi_implication' to calling error when they recognise `shorthand'.
For all predicates K that
a) switch on hlds_goal_expr and
b) perform non-trivial processing when they recognise
`bi_implication'
change K such that it now calls K_shorthand upon recognising the
functor `shorthand'. Define K_shorthand to switch on
shorthand_goal_expr, where the code for the `bi_implication' case
formerly contained in K is now contained in K_shorthand.
447 lines
16 KiB
Mathematica
447 lines
16 KiB
Mathematica
%-----------------------------------------------------------------------------%
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% Copyright (C) 1994-2001 The University of Melbourne.
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% This file may only be copied under the terms of the GNU General
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% Public License - see the file COPYING in the Mercury distribution.
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%-----------------------------------------------------------------------------%
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% Original author: conway.
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% Extensive modification by zs.
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% Allocates the storage location for each live variable at the end of
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% each branched structure, so that the code generator will generate code
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% which puts the variable in the same place in each branch.
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% This module requires arg_infos and livenesses to have already been computed,
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% and stack slots allocated.
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% If the appropriate option is set, the code calls the follow_vars module
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% to help guide its decisions.
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% See compiler/notes/allocation.html for a description of the framework that
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% this pass operates within.
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%-----------------------------------------------------------------------------%
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:- module store_alloc.
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:- interface.
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:- import_module hlds_module, hlds_pred.
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:- pred store_alloc_in_proc(proc_info, pred_id, module_info, proc_info).
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:- mode store_alloc_in_proc(in, in, in, out) is det.
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%-----------------------------------------------------------------------------%
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%-----------------------------------------------------------------------------%
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:- implementation.
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:- import_module follow_vars, liveness, hlds_goal, llds, prog_data.
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:- import_module options, globals, trace_params, trace.
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:- import_module goal_util, mode_util, instmap.
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:- import_module list, map, set, std_util, assoc_list.
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:- import_module bool, int, require.
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:- type stack_slot_info
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---> stack_slot_info(
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bool, % was follow_vars run?
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int, % the number of real r regs
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stack_slots % maps each var to its stack slot
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% (if it has one)
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).
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%-----------------------------------------------------------------------------%
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store_alloc_in_proc(ProcInfo0, PredId, ModuleInfo, ProcInfo) :-
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module_info_globals(ModuleInfo, Globals),
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globals__lookup_bool_option(Globals, follow_vars, ApplyFollowVars),
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( ApplyFollowVars = yes ->
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proc_info_goal(ProcInfo0, Goal0),
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find_final_follow_vars(ProcInfo0,
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FollowVarsMap0, NextNonReserved0),
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proc_info_vartypes(ProcInfo0, VarTypes),
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find_follow_vars_in_goal(Goal0, VarTypes, ModuleInfo,
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FollowVarsMap0, NextNonReserved0,
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Goal1, FollowVarsMap, NextNonReserved),
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Goal1 = GoalExpr1 - GoalInfo1,
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FollowVars = follow_vars(FollowVarsMap, NextNonReserved),
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goal_info_set_follow_vars(GoalInfo1, yes(FollowVars),
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GoalInfo2),
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Goal2 = GoalExpr1 - GoalInfo2
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;
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proc_info_goal(ProcInfo0, Goal2)
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),
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initial_liveness(ProcInfo0, PredId, ModuleInfo, Liveness0),
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globals__get_trace_level(Globals, TraceLevel),
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( trace_level_is_none(TraceLevel) = no ->
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trace__fail_vars(ModuleInfo, ProcInfo0, ResumeVars0)
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;
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set__init(ResumeVars0)
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),
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globals__lookup_int_option(Globals, num_real_r_regs, NumRealRRegs),
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proc_info_stack_slots(ProcInfo0, StackSlots),
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StackSlotsInfo = stack_slot_info(ApplyFollowVars, NumRealRRegs,
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StackSlots),
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store_alloc_in_goal(Goal2, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotsInfo, Goal, _),
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proc_info_set_goal(ProcInfo0, Goal, ProcInfo).
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%-----------------------------------------------------------------------------%
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:- pred store_alloc_in_goal(hlds_goal, liveness_info, set(prog_var),
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module_info, stack_slot_info, hlds_goal, liveness_info).
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:- mode store_alloc_in_goal(in, in, in, in, in, out, out) is det.
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store_alloc_in_goal(Goal0 - GoalInfo0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal - GoalInfo0, Liveness) :-
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% note: we must be careful to apply deaths before births
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goal_info_get_pre_deaths(GoalInfo0, PreDeaths),
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goal_info_get_pre_births(GoalInfo0, PreBirths),
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goal_info_get_post_deaths(GoalInfo0, PostDeaths),
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goal_info_get_post_births(GoalInfo0, PostBirths),
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set__difference(Liveness0, PreDeaths, Liveness1),
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set__union(Liveness1, PreBirths, Liveness2),
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store_alloc_in_goal_2(Goal0, Liveness2, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal1, Liveness3),
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set__difference(Liveness3, PostDeaths, Liveness4),
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% If any variables magically become live in the PostBirths,
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% then they have to mundanely become live in a parallel goal,
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% so we don't need to allocate anything for them here.
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%
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% Any variables that become magically live at the end of the goal
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% should not be included in the store map.
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set__union(Liveness4, PostBirths, Liveness),
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(
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Goal1 = switch(Var, CanFail, Cases, AdvisoryStoreMap)
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->
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set__union(Liveness4, ResumeVars0, MappedSet),
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set__to_sorted_list(MappedSet, MappedVars),
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store_alloc_allocate_storage(MappedVars, AdvisoryStoreMap,
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StackSlotInfo, StoreMap),
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Goal = switch(Var, CanFail, Cases, StoreMap)
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;
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Goal1 = if_then_else(Vars, Cond, Then, Else, AdvisoryStoreMap)
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->
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set__union(Liveness4, ResumeVars0, MappedSet),
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set__to_sorted_list(MappedSet, MappedVars),
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store_alloc_allocate_storage(MappedVars, AdvisoryStoreMap,
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StackSlotInfo, StoreMap),
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Goal = if_then_else(Vars, Cond, Then, Else, StoreMap)
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;
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Goal1 = disj(Disjuncts, AdvisoryStoreMap)
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->
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set__union(Liveness4, ResumeVars0, MappedSet),
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set__to_sorted_list(MappedSet, MappedVars),
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store_alloc_allocate_storage(MappedVars, AdvisoryStoreMap,
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StackSlotInfo, StoreMap),
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Goal = disj(Disjuncts, StoreMap)
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;
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Goal = Goal1
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).
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%-----------------------------------------------------------------------------%
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% Here we process each of the different sorts of goals.
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:- pred store_alloc_in_goal_2(hlds_goal_expr, liveness_info,
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set(prog_var), module_info, stack_slot_info, hlds_goal_expr,
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liveness_info).
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:- mode store_alloc_in_goal_2(in, in, in, in, in, out, out) is det.
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store_alloc_in_goal_2(conj(Goals0), Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, conj(Goals), Liveness) :-
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store_alloc_in_conj(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, Liveness).
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store_alloc_in_goal_2(par_conj(Goals0, SM), Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, par_conj(Goals, SM), Liveness) :-
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store_alloc_in_par_conj(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, Liveness).
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store_alloc_in_goal_2(disj(Goals0, FV), Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, disj(Goals, FV), Liveness) :-
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store_alloc_in_disj(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, Liveness).
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store_alloc_in_goal_2(not(Goal0), Liveness0, _ResumeVars0, ModuleInfo,
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StackSlotInfo, not(Goal), Liveness) :-
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Goal0 = _ - GoalInfo0,
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goal_info_get_resume_point(GoalInfo0, ResumeNot),
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goal_info_resume_vars_and_loc(ResumeNot, ResumeNotVars, _),
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store_alloc_in_goal(Goal0, Liveness0, ResumeNotVars, ModuleInfo,
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StackSlotInfo, Goal, Liveness).
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store_alloc_in_goal_2(switch(Var, Det, Cases0, FV), Liveness0, ResumeVars0,
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ModuleInfo, StackSlotInfo,
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switch(Var, Det, Cases, FV), Liveness) :-
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store_alloc_in_cases(Cases0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Cases, Liveness).
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store_alloc_in_goal_2(if_then_else(Vars, Cond0, Then0, Else0, FV),
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Liveness0, ResumeVars0, ModuleInfo, StackSlotInfo,
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if_then_else(Vars, Cond, Then, Else, FV), Liveness) :-
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Cond0 = _ - CondGoalInfo0,
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goal_info_get_resume_point(CondGoalInfo0, ResumeCond),
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goal_info_resume_vars_and_loc(ResumeCond, ResumeCondVars, _),
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store_alloc_in_goal(Cond0, Liveness0, ResumeCondVars, ModuleInfo,
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StackSlotInfo, Cond, Liveness1),
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store_alloc_in_goal(Then0, Liveness1, ResumeVars0, ModuleInfo,
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StackSlotInfo, Then, Liveness),
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store_alloc_in_goal(Else0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Else, _Liveness2).
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store_alloc_in_goal_2(some(Vars, CanRemove, Goal0), Liveness0, ResumeVars0,
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ModuleInfo,
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StackSlotInfo, some(Vars, CanRemove, Goal), Liveness) :-
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store_alloc_in_goal(Goal0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal, Liveness).
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store_alloc_in_goal_2(generic_call(A, B, C, D), Liveness, _, _,
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_, generic_call(A, B, C, D), Liveness).
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store_alloc_in_goal_2(call(A, B, C, D, E, F), Liveness, _, _,
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_, call(A, B, C, D, E, F), Liveness).
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store_alloc_in_goal_2(unify(A,B,C,D,E), Liveness, _, _,
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_, unify(A,B,C,D,E), Liveness).
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store_alloc_in_goal_2(foreign_proc(A, B, C, D, E, F, G), Liveness,
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_, _, _, foreign_proc(A, B, C, D, E, F, G), Liveness).
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store_alloc_in_goal_2(shorthand(_), _, _, _, _, _, _) :-
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% these should have been expanded out by now
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error("store_alloc_in_goal_2: unexpected shorthand").
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%-----------------------------------------------------------------------------%
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:- pred store_alloc_in_conj(list(hlds_goal), liveness_info, set(prog_var),
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module_info, stack_slot_info, list(hlds_goal), liveness_info).
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:- mode store_alloc_in_conj(in, in, in, in, in, out, out) is det.
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store_alloc_in_conj([], Liveness, _, _, _, [], Liveness).
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store_alloc_in_conj([Goal0 | Goals0], Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, [Goal | Goals], Liveness) :-
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(
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% XXX should be threading the instmap
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Goal0 = _ - GoalInfo,
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goal_info_get_instmap_delta(GoalInfo, InstMapDelta),
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instmap_delta_is_unreachable(InstMapDelta)
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->
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store_alloc_in_goal(Goal0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal, Liveness),
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Goals = Goals0
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;
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store_alloc_in_goal(Goal0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal, Liveness1),
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store_alloc_in_conj(Goals0, Liveness1, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, Liveness)
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).
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%-----------------------------------------------------------------------------%
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:- pred store_alloc_in_par_conj(list(hlds_goal), liveness_info, set(prog_var),
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module_info, stack_slot_info, list(hlds_goal), liveness_info).
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:- mode store_alloc_in_par_conj(in, in, in, in, in, out, out) is det.
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store_alloc_in_par_conj([], Liveness, _, _, _, [], Liveness).
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store_alloc_in_par_conj([Goal0 | Goals0], Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, [Goal | Goals], Liveness) :-
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store_alloc_in_goal(Goal0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal, Liveness),
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store_alloc_in_par_conj(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, _Liveness1).
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%-----------------------------------------------------------------------------%
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:- pred store_alloc_in_disj(list(hlds_goal), liveness_info, set(prog_var),
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module_info, stack_slot_info, list(hlds_goal), liveness_info).
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:- mode store_alloc_in_disj(in, in, in, in, in, out, out) is det.
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store_alloc_in_disj([], Liveness, _, _, _, [], Liveness).
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store_alloc_in_disj([Goal0 | Goals0], Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, [Goal | Goals], Liveness) :-
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Goal0 = _ - GoalInfo0,
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goal_info_get_resume_point(GoalInfo0, ResumeGoal),
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(
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ResumeGoal = no_resume_point,
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ResumeGoalVars = ResumeVars0
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;
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ResumeGoal = resume_point(ResumeGoalVars, _)
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),
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store_alloc_in_goal(Goal0, Liveness0, ResumeGoalVars, ModuleInfo,
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StackSlotInfo, Goal, Liveness),
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store_alloc_in_disj(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, _Liveness1).
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%-----------------------------------------------------------------------------%
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:- pred store_alloc_in_cases(list(case), liveness_info, set(prog_var),
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module_info, stack_slot_info, list(case), liveness_info).
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:- mode store_alloc_in_cases(in, in, in, in, in, out, out) is det.
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store_alloc_in_cases([], Liveness, _, _, _, [], Liveness).
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store_alloc_in_cases([case(Cons, Goal0) | Goals0], Liveness0, ResumeVars0,
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ModuleInfo, StackSlotInfo,
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[case(Cons, Goal) | Goals], Liveness) :-
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store_alloc_in_goal(Goal0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goal, Liveness),
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store_alloc_in_cases(Goals0, Liveness0, ResumeVars0, ModuleInfo,
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StackSlotInfo, Goals, _Liveness1).
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%-----------------------------------------------------------------------------%
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%-----------------------------------------------------------------------------%
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% Given a follow_map which
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%
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% 1 may contain entries for non-live variables,
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%
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% 2 may contain no entry for a live variable,
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%
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% 3 which may map two live variables to one lval, and/or
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%
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% 4 map an lval to the artificial location reg(r(-1)),
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%
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% generate a store map that maps every live variable to its own
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% real location.
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:- pred store_alloc_allocate_storage(list(prog_var), store_map,
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stack_slot_info, store_map).
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:- mode store_alloc_allocate_storage(in, in, in, out) is det.
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store_alloc_allocate_storage(LiveVars, FollowVars, StackSlotInfo, StoreMap) :-
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% This addresses point 1
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map__keys(FollowVars, FollowKeys),
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store_alloc_remove_nonlive(FollowKeys, LiveVars, FollowVars, StoreMap0),
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% This addresses points 3 and 4
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map__keys(StoreMap0, StoreVars),
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set__init(SeenLvals0),
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store_alloc_handle_conflicts_and_nonreal(StoreVars, 1, N,
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SeenLvals0, SeenLvals, StoreMap0, StoreMap1),
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% This addresses point 2
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store_alloc_allocate_extras(LiveVars, N, SeenLvals, StackSlotInfo,
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StoreMap1, StoreMap).
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:- pred store_alloc_remove_nonlive(list(prog_var), list(prog_var),
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store_map, store_map).
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:- mode store_alloc_remove_nonlive(in, in, in, out) is det.
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store_alloc_remove_nonlive([], _LiveVars, StoreMap, StoreMap).
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store_alloc_remove_nonlive([Var | Vars], LiveVars, StoreMap0, StoreMap) :-
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( list__member(Var, LiveVars) ->
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StoreMap1 = StoreMap0
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;
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map__delete(StoreMap0, Var, StoreMap1)
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),
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store_alloc_remove_nonlive(Vars, LiveVars, StoreMap1, StoreMap).
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:- pred store_alloc_handle_conflicts_and_nonreal(list(prog_var),
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int, int, set(lval), set(lval), store_map, store_map).
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:- mode store_alloc_handle_conflicts_and_nonreal(in, in, out, in, out, in, out)
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is det.
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store_alloc_handle_conflicts_and_nonreal([], N, N, SeenLvals, SeenLvals,
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StoreMap, StoreMap).
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store_alloc_handle_conflicts_and_nonreal([Var | Vars], N0, N,
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SeenLvals0, SeenLvals, StoreMap0, StoreMap) :-
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map__lookup(StoreMap0, Var, Lval),
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(
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( artificial_lval(Lval)
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; set__member(Lval, SeenLvals0)
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)
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->
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next_free_reg(N0, SeenLvals0, N1),
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FinalLval = reg(r, N1),
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map__det_update(StoreMap0, Var, FinalLval, StoreMap1)
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;
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N1 = N0,
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FinalLval = Lval,
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StoreMap1 = StoreMap0
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),
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set__insert(SeenLvals0, FinalLval, SeenLvals1),
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store_alloc_handle_conflicts_and_nonreal(Vars, N1, N,
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SeenLvals1, SeenLvals, StoreMap1, StoreMap).
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:- pred store_alloc_allocate_extras(list(prog_var), int, set(lval),
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stack_slot_info, store_map, store_map).
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:- mode store_alloc_allocate_extras(in, in, in, in, in, out) is det.
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store_alloc_allocate_extras([], _, _, _, StoreMap, StoreMap).
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store_alloc_allocate_extras([Var | Vars], N0, SeenLvals0, StackSlotInfo,
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StoreMap0, StoreMap) :-
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(
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map__contains(StoreMap0, Var)
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->
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% We have already allocated a slot for this variable.
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N1 = N0,
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StoreMap1 = StoreMap0,
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SeenLvals1 = SeenLvals0
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;
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% We have not yet allocated a slot for this variable,
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% which means it is not in the follow vars (if any).
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StackSlotInfo = stack_slot_info(FollowVars, NumRealRRegs,
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StackSlots),
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(
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map__search(StackSlots, Var, StackSlot),
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|
\+ set__member(StackSlot, SeenLvals0),
|
|
(
|
|
FollowVars = yes
|
|
% If follow_vars was run, then the only
|
|
% reason why a var would not be in the
|
|
% follow_vars set is if it was supposed to
|
|
% be in its stack slot.
|
|
;
|
|
FollowVars = no,
|
|
% If follow_vars was not run, then we
|
|
% prefer to put the variable in a register,
|
|
% provided it is a real register.
|
|
next_free_reg(N0, SeenLvals0, TentativeReg),
|
|
TentativeReg =< NumRealRRegs
|
|
)
|
|
->
|
|
Locn = StackSlot,
|
|
N1 = N0
|
|
;
|
|
next_free_reg(N0, SeenLvals0, N1),
|
|
Locn = reg(r, N1)
|
|
),
|
|
map__det_insert(StoreMap0, Var, Locn, StoreMap1),
|
|
set__insert(SeenLvals0, Locn, SeenLvals1)
|
|
),
|
|
store_alloc_allocate_extras(Vars, N1, SeenLvals1, StackSlotInfo,
|
|
StoreMap1, StoreMap).
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
% The follow_vars pass maps some variables r(-1) as a hint to the
|
|
% code generator to put them in any free register. Since store maps
|
|
% require real locations, we can't use such hints directly.
|
|
|
|
% For robustness, we check for N < 1 instead of N = -1.
|
|
|
|
:- pred artificial_lval(lval).
|
|
:- mode artificial_lval(in) is semidet.
|
|
|
|
artificial_lval(reg(_Type, Num)) :-
|
|
Num < 1.
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- pred next_free_reg(int, set(lval), int).
|
|
:- mode next_free_reg(in, in, out) is det.
|
|
|
|
next_free_reg(N0, Values, N) :-
|
|
( set__member(reg(r, N0), Values) ->
|
|
N1 is N0 + 1,
|
|
next_free_reg(N1, Values, N)
|
|
;
|
|
N = N0
|
|
).
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
%-----------------------------------------------------------------------------%
|