lustrec / src / machine_code.ml @ 1e48ef45
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(********************************************************************) 

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(* *) 
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(* The LustreC compiler toolset / The LustreC Development Team *) 
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(* Copyright 2012   ONERA  CNRS  INPT *) 
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(* *) 
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(* LustreC is free software, distributed WITHOUT ANY WARRANTY *) 
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(* under the terms of the GNU Lesser General Public License *) 
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(* version 2.1. *) 
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(* *) 
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(********************************************************************) 
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open LustreSpec 
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open Corelang 
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open Clocks 
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open Causality 
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exception NormalizationError 
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module OrdVarDecl:Map.OrderedType with type t=var_decl = 
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struct type t = var_decl;; let compare = compare end 
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module ISet = Set.Make(OrdVarDecl) 
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type value_t = 
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 Cst of constant 
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 LocalVar of var_decl 
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 StateVar of var_decl 
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 Fun of ident * value_t list 
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 Array of value_t list 
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 Access of value_t * value_t 
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 Power of value_t * value_t 
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type instr_t = 
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 MLocalAssign of var_decl * value_t 
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 MStateAssign of var_decl * value_t 
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 MReset of ident 
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 MStep of var_decl list * ident * value_t list 
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 MBranch of value_t * (label * instr_t list) list 
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let rec pp_val fmt v = 
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match v with 
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 Cst c > Printers.pp_const fmt c 
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 LocalVar v > Format.pp_print_string fmt v.var_id 
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 StateVar v > Format.pp_print_string fmt v.var_id 
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 Array vl > Format.fprintf fmt "[%a]" (Utils.fprintf_list ~sep:", " pp_val) vl 
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 Access (t, i) > Format.fprintf fmt "%a[%a]" pp_val t pp_val i 
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 Power (v, n) > Format.fprintf fmt "(%a^%a)" pp_val v pp_val n 
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 Fun (n, vl) > Format.fprintf fmt "%s (%a)" n (Utils.fprintf_list ~sep:", " pp_val) vl 
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let rec pp_instr fmt i = 
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match i with 
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 MLocalAssign (i,v) > Format.fprintf fmt "%s<l %a" i.var_id pp_val v 
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 MStateAssign (i,v) > Format.fprintf fmt "%s<s %a" i.var_id pp_val v 
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 MReset i > Format.fprintf fmt "reset %s" i 
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 MStep (il, i, vl) > 
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Format.fprintf fmt "%a = %s (%a)" 
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(Utils.fprintf_list ~sep:", " (fun fmt v > Format.pp_print_string fmt v.var_id)) il 
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i 
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(Utils.fprintf_list ~sep:", " pp_val) vl 
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 MBranch (g,hl) > 
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Format.fprintf fmt "@[<v 2>case(%a) {@,%a@,}@]" 
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pp_val g 
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(Utils.fprintf_list ~sep:"@," pp_branch) hl 
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and pp_branch fmt (t, h) = 
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Format.fprintf fmt "@[<v 2>%s:@,%a@]" t (Utils.fprintf_list ~sep:"@," pp_instr) h 
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type step_t = { 
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step_checks: (Location.t * value_t) list; 
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step_inputs: var_decl list; 
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step_outputs: var_decl list; 
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step_locals: var_decl list; 
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step_instrs: instr_t list; 
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step_asserts: value_t list; 
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} 
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type static_call = top_decl * (Dimension.dim_expr list) 
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type machine_t = { 
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mname: node_desc; 
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mmemory: var_decl list; 
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mcalls: (ident * static_call) list; (* map from stateful/stateless instance to node, no internals *) 
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minstances: (ident * static_call) list; (* submap of mcalls, from stateful instance to node *) 
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minit: instr_t list; 
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mstatic: var_decl list; (* static inputs only *) 
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mstep: step_t; 
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mspec: node_annot option; 
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mannot: expr_annot list; 
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} 
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let pp_step fmt s = 
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Format.fprintf fmt "@[<v>inputs : %a@ outputs: %a@ locals : %a@ checks : %a@ instrs : @[%a@]@ asserts : @[%a@]@]@ " 
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(Utils.fprintf_list ~sep:", " Printers.pp_var) s.step_inputs 
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(Utils.fprintf_list ~sep:", " Printers.pp_var) s.step_outputs 
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(Utils.fprintf_list ~sep:", " Printers.pp_var) s.step_locals 
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(Utils.fprintf_list ~sep:", " (fun fmt (_, c) > pp_val fmt c)) s.step_checks 
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(Utils.fprintf_list ~sep:"@ " pp_instr) s.step_instrs 
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(Utils.fprintf_list ~sep:", " pp_val) s.step_asserts 
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let pp_static_call fmt (node, args) = 
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Format.fprintf fmt "%s<%a>" 
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(node_name node) 
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(Utils.fprintf_list ~sep:", " Dimension.pp_dimension) args 
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let pp_machine fmt m = 
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Format.fprintf fmt 
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"@[<v 2>machine %s@ mem : %a@ instances: %a@ init : %a@ step :@ @[<v 2>%a@]@ @ spec : @[%t@]@ annot : @[%a@]@]@ " 
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m.mname.node_id 
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(Utils.fprintf_list ~sep:", " Printers.pp_var) m.mmemory 
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(Utils.fprintf_list ~sep:", " (fun fmt (o1, o2) > Format.fprintf fmt "(%s, %a)" o1 pp_static_call o2)) m.minstances 
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(Utils.fprintf_list ~sep:"@ " pp_instr) m.minit 
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pp_step m.mstep 
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(fun fmt > match m.mspec with  None > ()  Some spec > Printers.pp_spec fmt spec) 
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(Utils.fprintf_list ~sep:"@ " Printers.pp_expr_annot) m.mannot 
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(* Returns the declared stateless status and the computed one. *) 
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let get_stateless_status m = 
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(m.mname.node_dec_stateless, Utils.desome m.mname.node_stateless) 
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let is_input m id = 
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List.exists (fun o > o.var_id = id.var_id) m.mstep.step_inputs 
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let is_output m id = 
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List.exists (fun o > o.var_id = id.var_id) m.mstep.step_outputs 
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let is_memory m id = 
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List.exists (fun o > o.var_id = id.var_id) m.mmemory 
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let conditional c t e = 
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MBranch(c, [ (tag_true, t); (tag_false, e) ]) 
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let dummy_var_decl name typ = 
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{ 
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var_id = name; 
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var_orig = false; 
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var_dec_type = dummy_type_dec; 
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var_dec_clock = dummy_clock_dec; 
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var_dec_const = false; 
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var_type = typ; 
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var_clock = Clocks.new_ck (Clocks.Cvar Clocks.CSet_all) true; 
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var_loc = Location.dummy_loc 
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} 
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let arrow_id = "_arrow" 
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let arrow_typ = Types.new_ty Types.Tunivar 
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let arrow_desc = 
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{ 
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node_id = arrow_id; 
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node_type = Type_predef.type_bin_poly_op; 
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node_clock = Clock_predef.ck_bin_univ; 
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node_inputs= [dummy_var_decl "_in1" arrow_typ; dummy_var_decl "_in2" arrow_typ]; 
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node_outputs= [dummy_var_decl "_out" arrow_typ]; 
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node_locals= []; 
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node_gencalls = []; 
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node_checks = []; 
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node_asserts = []; 
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node_stmts= []; 
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node_dec_stateless = false; 
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node_stateless = Some false; 
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node_spec = None; 
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node_annot = []; } 
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let arrow_top_decl = 
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{ 
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top_decl_desc = Node arrow_desc; 
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top_decl_owner = Version.include_path; 
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top_decl_itf = false; 
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top_decl_loc = Location.dummy_loc 
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} 
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let arrow_machine = 
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let state = "_first" in 
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let var_state = dummy_var_decl state (Types.new_ty Types.Tbool) in 
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let var_input1 = List.nth arrow_desc.node_inputs 0 in 
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let var_input2 = List.nth arrow_desc.node_inputs 1 in 
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let var_output = List.nth arrow_desc.node_outputs 0 in 
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{ 
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mname = arrow_desc; 
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mmemory = [var_state]; 
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mcalls = []; 
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minstances = []; 
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minit = [MStateAssign(var_state, Cst (const_of_bool true))]; 
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mstatic = []; 
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mstep = { 
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step_inputs = arrow_desc.node_inputs; 
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step_outputs = arrow_desc.node_outputs; 
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step_locals = []; 
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step_checks = []; 
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step_instrs = [conditional (StateVar var_state) 
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[MStateAssign(var_state, Cst (const_of_bool false)); 
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MLocalAssign(var_output, LocalVar var_input1)] 
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[MLocalAssign(var_output, LocalVar var_input2)] ]; 
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step_asserts = []; 
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}; 
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mspec = None; 
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mannot = []; 
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} 
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let new_instance = 
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let cpt = ref (1) in 
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fun caller callee tag > 
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begin 
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let o = 
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if Stateless.check_node callee then 
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node_name callee 
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else 
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Printf.sprintf "ni_%d" (incr cpt; !cpt) in 
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let o = 
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if !Options.ansi && is_generic_node callee 
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then Printf.sprintf "%s_inst_%d" o (Utils.position (fun e > e.expr_tag = tag) caller.node_gencalls) 
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else o in 
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o 
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end 
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(* translate_<foo> : node > context > <foo> > machine code/expression *) 
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(* the context contains m : state aka memory variables *) 
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(* si : initialization instructions *) 
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(* j : node aka machine instances *) 
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(* d : local variables *) 
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(* s : step instructions *) 
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let translate_ident node (m, si, j, d, s) id = 
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try (* id is a node var *) 
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let var_id = get_node_var id node in 
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if ISet.exists (fun v > v.var_id = id) m 
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then StateVar var_id 
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else LocalVar var_id 
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with Not_found > 
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try (* id is a constant *) 
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LocalVar (Corelang.var_decl_of_const (const_of_top (Hashtbl.find Corelang.consts_table id))) 
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with Not_found > 
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(* id is a tag *) 
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Cst (Const_tag id) 
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let rec control_on_clock node ((m, si, j, d, s) as args) ck inst = 
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match (Clocks.repr ck).cdesc with 
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 Con (ck1, cr, l) > 
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let id = Clocks.const_of_carrier cr in 
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control_on_clock node args ck1 (MBranch (translate_ident node args id, 
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[l, [inst]] )) 
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 _ > inst 
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let rec join_branches hl1 hl2 = 
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match hl1, hl2 with 
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 [] , _ > hl2 
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 _ , [] > hl1 
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 (t1, h1)::q1, (t2, h2)::q2 > 
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if t1 < t2 then (t1, h1) :: join_branches q1 hl2 else 
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if t1 > t2 then (t2, h2) :: join_branches hl1 q2 
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else (t1, List.fold_right join_guards h1 h2) :: join_branches q1 q2 
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and join_guards inst1 insts2 = 
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match inst1, insts2 with 
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 _ , [] > 
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[inst1] 
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 MBranch (x1, hl1), MBranch (x2, hl2) :: q when x1 = x2 > 
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MBranch (x1, join_branches (sort_handlers hl1) (sort_handlers hl2)) 
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:: q 
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 _ > inst1 :: insts2 
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let join_guards_list insts = 
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List.fold_right join_guards insts [] 
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(* specialize predefined (polymorphic) operators 
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wrt their instances, so that the C semantics 
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is preserved *) 
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let specialize_to_c expr = 
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match expr.expr_desc with 
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 Expr_appl (id, e, r) > 
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if List.exists (fun e > Types.is_bool_type e.expr_type) (expr_list_of_expr e) 
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then let id = 
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match id with 
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 "=" > "equi" 
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 "!=" > "xor" 
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 _ > id in 
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{ expr with expr_desc = Expr_appl (id, e, r) } 
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else expr 
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 _ > expr 
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let specialize_op expr = 
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match !Options.output with 
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 "C" > specialize_to_c expr 
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 _ > expr 
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let rec translate_expr node ((m, si, j, d, s) as args) expr = 
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let expr = specialize_op expr in 
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match expr.expr_desc with 
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 Expr_const v > Cst v 
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 Expr_ident x > translate_ident node args x 
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 Expr_array el > Array (List.map (translate_expr node args) el) 
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 Expr_access (t, i) > Access (translate_expr node args t, translate_expr node args (expr_of_dimension i)) 
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 Expr_power (e, n) > Power (translate_expr node args e, translate_expr node args (expr_of_dimension n)) 
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 Expr_tuple _ 
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 Expr_arrow _ 
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 Expr_fby _ 
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 Expr_pre _ > (Printers.pp_expr Format.err_formatter expr; Format.pp_print_flush Format.err_formatter (); raise NormalizationError) 
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 Expr_when (e1, _, _) > translate_expr node args e1 
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 Expr_merge (x, _) > raise NormalizationError 
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 Expr_appl (id, e, _) when Basic_library.is_internal_fun id > 
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let nd = node_from_name id in 
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Fun (node_name nd, List.map (translate_expr node args) (expr_list_of_expr e)) 
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 Expr_ite (g,t,e) > ( 
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(* special treatment depending on the active backend. For horn backend, ite 
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are preserved in expression. While they are removed for C or Java 
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backends. *) 
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match !Options.output with  "horn" > 
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Fun ("ite", [translate_expr node args g; translate_expr node args t; translate_expr node args e]) 
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 "C"  "java"  _ > 
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(Printers.pp_expr Format.err_formatter expr; Format.pp_print_flush Format.err_formatter (); raise NormalizationError) 
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) 
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 _ > raise NormalizationError 
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let translate_guard node args expr = 
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match expr.expr_desc with 
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 Expr_ident x > translate_ident node args x 
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 _ > (Format.eprintf "internal error: translate_guard %s %a@." node.node_id Printers.pp_expr expr;assert false) 
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let rec translate_act node ((m, si, j, d, s) as args) (y, expr) = 
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match expr.expr_desc with 
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 Expr_ite (c, t, e) > let g = translate_guard node args c in 
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conditional g [translate_act node args (y, t)] 
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[translate_act node args (y, e)] 
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 Expr_merge (x, hl) > MBranch (translate_ident node args x, List.map (fun (t, h) > t, [translate_act node args (y, h)]) hl) 
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 _ > MLocalAssign (y, translate_expr node args expr) 
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let reset_instance node args i r c = 
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match r with 
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 None > [] 
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 Some r > let g = translate_guard node args r in 
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[control_on_clock node args c (conditional g [MReset i] [])] 
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let translate_eq node ((m, si, j, d, s) as args) eq = 
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(*Format.eprintf "translate_eq %a with clock %a@." Printers.pp_node_eq eq Clocks.print_ck eq.eq_rhs.expr_clock;*) 
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match eq.eq_lhs, eq.eq_rhs.expr_desc with 
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 [x], Expr_arrow (e1, e2) > 
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let var_x = get_node_var x node in 
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let o = new_instance node arrow_top_decl eq.eq_rhs.expr_tag in 
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let c1 = translate_expr node args e1 in 
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let c2 = translate_expr node args e2 in 
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(m, 
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MReset o :: si, 
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Utils.IMap.add o (arrow_top_decl, []) j, 
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d, 
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(control_on_clock node args eq.eq_rhs.expr_clock (MStep ([var_x], o, [c1;c2]))) :: s) 
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 [x], Expr_pre e1 when ISet.mem (get_node_var x node) d > 
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let var_x = get_node_var x node in 
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(ISet.add var_x m, 
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si, 
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j, 
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d, 
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control_on_clock node args eq.eq_rhs.expr_clock (MStateAssign (var_x, translate_expr node args e1)) :: s) 
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 [x], Expr_fby (e1, e2) when ISet.mem (get_node_var x node) d > 
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let var_x = get_node_var x node in 
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(ISet.add var_x m, 
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MStateAssign (var_x, translate_expr node args e1) :: si, 
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j, 
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d, 
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control_on_clock node args eq.eq_rhs.expr_clock (MStateAssign (var_x, translate_expr node args e2)) :: s) 
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 p , Expr_appl (f, arg, r) when not (Basic_library.is_internal_fun f) > 
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let var_p = List.map (fun v > get_node_var v node) p in 
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let el = expr_list_of_expr arg in 
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let vl = List.map (translate_expr node args) el in 
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let node_f = node_from_name f in 
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let call_f = 
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node_f, 
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NodeDep.filter_static_inputs (node_inputs node_f) el in 
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let o = new_instance node node_f eq.eq_rhs.expr_tag in 
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let env_cks = List.fold_right (fun arg cks > arg.expr_clock :: cks) el [eq.eq_rhs.expr_clock] in 
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let call_ck = Clock_calculus.compute_root_clock (Clock_predef.ck_tuple env_cks) in 
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(*Clocks.new_var true in 
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Clock_calculus.unify_imported_clock (Some call_ck) eq.eq_rhs.expr_clock eq.eq_rhs.expr_loc; 
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Format.eprintf "call %a: %a: %a@," Printers.pp_expr eq.eq_rhs Clocks.print_ck (Clock_predef.ck_tuple env_cks) Clocks.print_ck call_ck;*) 
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(m, 
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(if Stateless.check_node node_f then si else MReset o :: si), 
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Utils.IMap.add o call_f j, 
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d, 
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(if Stateless.check_node node_f 
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then [] 
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else reset_instance node args o r call_ck) @ 
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(control_on_clock node args call_ck (MStep (var_p, o, vl))) :: s) 
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(* special treatment depending on the active backend. For horn backend, x = ite (g,t,e) 
386 
are preserved. While they are replaced as if g then x = t else x = e in C or Java 
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backends. *) 
388 
 [x], Expr_ite (c, t, e) 
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when (match !Options.output with  "horn" > true  "C"  "java"  _ > false) 
390 
> 
391 
let var_x = get_node_var x node in 
392 
(m, 
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si, 
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j, 
395 
d, 
396 
(control_on_clock node args eq.eq_rhs.expr_clock 
397 
(MLocalAssign (var_x, translate_expr node args eq.eq_rhs))::s) 
398 
) 
399 

400 
 [x], _ > ( 
401 
let var_x = get_node_var x node in 
402 
(m, si, j, d, 
403 
control_on_clock 
404 
node 
405 
args 
406 
eq.eq_rhs.expr_clock 
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(translate_act node args (var_x, eq.eq_rhs)) :: s 
408 
) 
409 
) 
410 
 _ > 
411 
begin 
412 
Format.eprintf "unsupported equation: %a@?" Printers.pp_node_eq eq; 
413 
assert false 
414 
end 
415  
416 
let find_eq xl eqs = 
417 
let rec aux accu eqs = 
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match eqs with 
419 
 [] > 
420 
begin 
421 
Format.eprintf "Looking for variables %a in the following equations@.%a@." 
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(Utils.fprintf_list ~sep:" , " (fun fmt v > Format.fprintf fmt "%s" v)) xl 
423 
Printers.pp_node_eqs eqs; 
424 
assert false 
425 
end 
426 
 hd::tl > 
427 
if List.exists (fun x > List.mem x hd.eq_lhs) xl then hd, accu@tl else aux (hd::accu) tl 
428 
in 
429 
aux [] eqs 
430  
431 
(* Sort the set of equations of node [nd] according 
432 
to the computed schedule [sch] 
433 
*) 
434 
let sort_equations_from_schedule nd sch = 
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(* Format.eprintf "%s schedule: %a@." 
436 
nd.node_id 
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(Utils.fprintf_list ~sep:" ; " Scheduling.pp_eq_schedule) sch;*) 
438 
let split_eqs = Splitting.tuple_split_eq_list (get_node_eqs nd) in 
439 
let eqs_rev, remainder = 
440 
List.fold_left 
441 
(fun (accu, node_eqs_remainder) vl > 
442 
if List.exists (fun eq > List.exists (fun v > List.mem v eq.eq_lhs) vl) accu 
443 
then 
444 
(accu, node_eqs_remainder) 
445 
else 
446 
let eq_v, remainder = find_eq vl node_eqs_remainder in 
447 
eq_v::accu, remainder 
448 
) 
449 
([], split_eqs) 
450 
sch 
451 
in 
452 
begin 
453 
if List.length remainder > 0 then ( 
454 
Format.eprintf "Equations not used are@.%a@.Full equation set is:@.%a@.@?" 
455 
Printers.pp_node_eqs remainder 
456 
Printers.pp_node_eqs (get_node_eqs nd); 
457 
assert false); 
458 
List.rev eqs_rev 
459 
end 
460  
461 
let translate_eqs node args eqs = 
462 
List.fold_right (fun eq args > translate_eq node args eq) eqs args;; 
463  
464 
let translate_decl nd sch = 
465 
(*Log.report ~level:1 (fun fmt > Printers.pp_node fmt nd);*) 
466  
467 
let sorted_eqs = sort_equations_from_schedule nd sch in 
468  
469 
let init_args = ISet.empty, [], Utils.IMap.empty, List.fold_right (fun l > ISet.add l) nd.node_locals ISet.empty, [] in 
470 
(* memories, init instructions, node calls, local variables (including memories), step instrs *) 
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let m, init, j, locals, s = translate_eqs nd init_args sorted_eqs in 
472 
let mmap = Utils.IMap.fold (fun i n res > (i, n)::res) j [] in 
473 
{ 
474 
mname = nd; 
475 
mmemory = ISet.elements m; 
476 
mcalls = mmap; 
477 
minstances = List.filter (fun (_, (n,_)) > not (Stateless.check_node n)) mmap; 
478 
minit = init; 
479 
mstatic = List.filter (fun v > v.var_dec_const) nd.node_inputs; 
480 
mstep = { 
481 
step_inputs = nd.node_inputs; 
482 
step_outputs = nd.node_outputs; 
483 
step_locals = ISet.elements (ISet.diff locals m); 
484 
step_checks = List.map (fun d > d.Dimension.dim_loc, translate_expr nd init_args (expr_of_dimension d)) nd.node_checks; 
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step_instrs = ( 
486 
(* special treatment depending on the active backend. For horn backend, 
487 
common branches are not merged while they are in C or Java 
488 
backends. *) 
489 
match !Options.output with 
490 
 "horn" > s 
491 
 "C"  "java"  _ > join_guards_list s 
492 
); 
493 
step_asserts = 
494 
let exprl = List.map (fun assert_ > assert_.assert_expr ) nd.node_asserts in 
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List.map (translate_expr nd init_args) exprl 
496 
; 
497 
}; 
498 
mspec = nd.node_spec; 
499 
mannot = nd.node_annot; 
500 
} 
501  
502 
(** takes the global delcarations and the scheduling associated to each node *) 
503 
let translate_prog decls node_schs = 
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let nodes = get_nodes decls in 
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List.map 
506 
(fun decl > 
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let node = node_of_top decl in 
508 
let sch = (Utils.IMap.find node.node_id node_schs).Scheduling.schedule in 
509 
translate_decl node sch 
510 
) nodes 
511  
512 
let get_machine_opt name machines = 
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List.fold_left 
514 
(fun res m > 
515 
match res with 
516 
 Some _ > res 
517 
 None > if m.mname.node_id = name then Some m else None) 
518 
None machines 
519 

520  
521 
(* Local Variables: *) 
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(* compilecommand:"make C .." *) 
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(* End: *) 