## lustrec / src / causality.ml @ a1daa793

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1 | e2068500 | Temesghen Kahsai | (********************************************************************) |
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2 | (* *) |
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3 | (* The LustreC compiler toolset / The LustreC Development Team *) |
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4 | (* Copyright 2012 - -- ONERA - CNRS - INPT - LIFL *) |
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5 | (* *) |
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6 | (* LustreC is free software, distributed WITHOUT ANY WARRANTY *) |
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7 | (* under the terms of the GNU Lesser General Public License *) |
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8 | (* version 2.1. *) |
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9 | (* *) |
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10 | (* This file was originally from the Prelude compiler *) |
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11 | (* *) |
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12 | (********************************************************************) |
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13 | |||

14 | |||

15 | (** Simple modular syntactic causality analysis. Can reject correct |
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16 | programs, especially if the program is not flattened first. *) |
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17 | open Utils |
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18 | open LustreSpec |
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19 | open Corelang |
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20 | open Graph |
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21 | open Format |
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22 | |||

23 | exception Cycle of ident list |
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24 | |||

25 | module IdentDepGraph = Graph.Imperative.Digraph.ConcreteBidirectional (IdentModule) |
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26 | |||

27 | (* Dependency of mem variables on mem variables is cut off |
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28 | by duplication of some mem vars into local node vars. |
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29 | Thus, cylic dependency errors may only arise between no-mem vars. |
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30 | non-mem variables are: |
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31 | d50b0dc0 | Temesghen Kahsai | - constants/inputs: not needed for causality/scheduling, needed only for detecting useless vars |

32 | e2068500 | Temesghen Kahsai | - read mems (fake vars): same remark as above. |

33 | - outputs: decoupled from mems, if necessary |
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34 | - locals |
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35 | - instance vars (fake vars): simplify causality analysis |
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36 | |||

37 | global constants are not part of the dependency graph. |
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38 | |||

39 | no_mem' = combinational(no_mem, mem); |
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40 | => (mem -> no_mem' -> no_mem) |
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41 | |||

42 | mem' = pre(no_mem, mem); |
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43 | => (mem' -> no_mem), (mem -> mem') |
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44 | |||

45 | Global roadmap: |
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46 | - compute two dep graphs g (non-mem/non-mem&mem) and g' (mem/mem) |
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47 | - check cycles in g (a cycle means a dependency error) |
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48 | - break cycles in g' (it's legal !): |
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49 | - check cycles in g' |
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50 | - if any, introduce aux var to break cycle, then start afresh |
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51 | - insert g' into g |
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52 | - return g |
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53 | *) |
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54 | |||

55 | (* Tests whether [v] is a root of graph [g], i.e. a source *) |
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56 | let is_graph_root v g = |
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57 | IdentDepGraph.in_degree g v = 0 |
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58 | |||

59 | (* Computes the set of graph roots, i.e. the sources of acyclic graph [g] *) |
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60 | let graph_roots g = |
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61 | IdentDepGraph.fold_vertex |
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62 | (fun v roots -> if is_graph_root v g then v::roots else roots) |
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63 | g [] |
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64 | |||

65 | let add_edges src tgt g = |
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66 | (*List.iter (fun s -> List.iter (fun t -> Format.eprintf "add %s -> %s@." s t) tgt) src;*) |
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67 | List.iter |
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68 | (fun s -> |
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69 | List.iter |
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70 | (fun t -> IdentDepGraph.add_edge g s t) |
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71 | tgt) |
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72 | src; |
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73 | g |
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74 | |||

75 | let add_vertices vtc g = |
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76 | (*List.iter (fun t -> Format.eprintf "add %s@." t) vtc;*) |
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77 | List.iter (fun v -> IdentDepGraph.add_vertex g v) vtc; |
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78 | g |
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79 | |||

80 | let new_graph () = |
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81 | IdentDepGraph.create () |
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82 | |||

83 | module ExprDep = struct |
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84 | |||

85 | let instance_var_cpt = ref 0 |
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86 | |||

87 | (* read vars represent input/mem read-only vars, |
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88 | they are not part of the program/schedule, |
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89 | as they are not assigned, |
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90 | but used to compute useless inputs/mems. |
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91 | a mem read var represents a mem at the beginning of a cycle *) |
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92 | let mk_read_var id = |
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93 | sprintf "#%s" id |
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94 | |||

95 | (* instance vars represent node instance calls, |
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96 | they are not part of the program/schedule, |
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97 | but used to simplify causality analysis |
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98 | *) |
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99 | let mk_instance_var id = |
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100 | incr instance_var_cpt; sprintf "!%s_%d" id !instance_var_cpt |
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101 | |||

102 | let is_read_var v = v.[0] = '#' |
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103 | |||

104 | let is_instance_var v = v.[0] = '!' |
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105 | |||

106 | let is_ghost_var v = is_instance_var v || is_read_var v |
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107 | |||

108 | let undo_read_var id = |
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109 | assert (is_read_var id); |
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110 | String.sub id 1 (String.length id - 1) |
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111 | |||

112 | let undo_instance_var id = |
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113 | assert (is_instance_var id); |
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114 | String.sub id 1 (String.length id - 1) |
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115 | |||

116 | let eq_memory_variables mems eq = |
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117 | let rec match_mem lhs rhs mems = |
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118 | match rhs.expr_desc with |
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119 | | Expr_fby _ |
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120 | | Expr_pre _ -> List.fold_right ISet.add lhs mems |
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121 | | Expr_tuple tl -> |
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122 | let lhs' = (transpose_list [lhs]) in |
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123 | List.fold_right2 match_mem lhs' tl mems |
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124 | | _ -> mems in |
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125 | match_mem eq.eq_lhs eq.eq_rhs mems |
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126 | |||

127 | let node_memory_variables nd = |
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128 | List.fold_left eq_memory_variables ISet.empty (get_node_eqs nd) |
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129 | |||

130 | let node_input_variables nd = |
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131 | List.fold_left (fun inputs v -> ISet.add v.var_id inputs) ISet.empty nd.node_inputs |
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132 | |||

133 | let node_local_variables nd = |
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134 | List.fold_left (fun locals v -> ISet.add v.var_id locals) ISet.empty nd.node_locals |
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135 | |||

136 | d50b0dc0 | Temesghen Kahsai | let node_constant_variables nd = |

137 | List.fold_left (fun locals v -> if v.var_dec_const then ISet.add v.var_id locals else locals) ISet.empty nd.node_locals |
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138 | |||

139 | e2068500 | Temesghen Kahsai | let node_output_variables nd = |

140 | List.fold_left (fun outputs v -> ISet.add v.var_id outputs) ISet.empty nd.node_outputs |
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141 | |||

142 | let node_auxiliary_variables nd = |
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143 | ISet.diff (node_local_variables nd) (node_memory_variables nd) |
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144 | |||

145 | let node_variables nd = |
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146 | let inputs = node_input_variables nd in |
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147 | let inoutputs = List.fold_left (fun inoutputs v -> ISet.add v.var_id inoutputs) inputs nd.node_outputs in |
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148 | List.fold_left (fun vars v -> ISet.add v.var_id vars) inoutputs nd.node_locals |
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149 | |||

150 | (* computes the equivalence relation relating variables |
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151 | in the same equation lhs, under the form of a table |
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152 | of class representatives *) |
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153 | let node_eq_equiv nd = |
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154 | let eq_equiv = Hashtbl.create 23 in |
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155 | List.iter (fun eq -> |
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156 | let first = List.hd eq.eq_lhs in |
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157 | List.iter (fun v -> Hashtbl.add eq_equiv v first) eq.eq_lhs |
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158 | ) |
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159 | (get_node_eqs nd); |
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160 | eq_equiv |
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161 | |||

162 | (* Create a tuple of right dimension, according to [expr] type, *) |
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163 | (* filled with variable [v] *) |
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164 | let adjust_tuple v expr = |
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165 | match expr.expr_type.Types.tdesc with |
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166 | | Types.Ttuple tl -> duplicate v (List.length tl) |
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167 | | _ -> [v] |
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168 | |||

169 | |||

170 | (* Add dependencies from lhs to rhs in [g, g'], *) |
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171 | (* no-mem/no-mem and mem/no-mem in g *) |
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172 | (* mem/mem in g' *) |
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173 | (* match (lhs_is_mem, ISet.mem x mems) with |
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174 | | (false, true ) -> (add_edges [x] lhs g, |
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175 | g') |
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176 | | (false, false) -> (add_edges lhs [x] g, |
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177 | g') |
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178 | | (true , false) -> (add_edges lhs [x] g, |
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179 | g') |
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180 | | (true , true ) -> (g, |
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181 | add_edges [x] lhs g') |
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182 | *) |
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183 | let add_eq_dependencies mems inputs node_vars eq (g, g') = |
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184 | let add_var lhs_is_mem lhs x (g, g') = |
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185 | if is_instance_var x || ISet.mem x node_vars then |
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186 | if ISet.mem x mems |
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187 | then |
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188 | let g = add_edges lhs [mk_read_var x] g in |
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189 | if lhs_is_mem |
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190 | then |
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191 | (g, add_edges [x] lhs g') |
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192 | else |
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193 | (add_edges [x] lhs g, g') |
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194 | else |
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195 | let x = if ISet.mem x inputs then mk_read_var x else x in |
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196 | (add_edges lhs [x] g, g') |
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197 | else (add_edges lhs [mk_read_var x] g, g') (* x is a global constant, treated as a read var *) in |
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198 | (* Add dependencies from [lhs] to rhs clock [ck]. *) |
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199 | let rec add_clock lhs_is_mem lhs ck g = |
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200 | (*Format.eprintf "add_clock %a@." Clocks.print_ck ck;*) |
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201 | match (Clocks.repr ck).Clocks.cdesc with |
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202 | | Clocks.Con (ck', cr, _) -> add_var lhs_is_mem lhs (Clocks.const_of_carrier cr) (add_clock lhs_is_mem lhs ck' g) |
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203 | | Clocks.Ccarrying (_, ck') -> add_clock lhs_is_mem lhs ck' g |
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204 | | _ -> g |
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205 | in |
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206 | let rec add_dep lhs_is_mem lhs rhs g = |
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207 | (* Add mashup dependencies for a user-defined node instance [lhs] = [f]([e]) *) |
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208 | (* i.e every input is connected to every output, through a ghost var *) |
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209 | let mashup_appl_dependencies f e g = |
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210 | let f_var = mk_instance_var (sprintf "%s_%d" f eq.eq_loc.Location.loc_start.Lexing.pos_lnum) in |
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211 | List.fold_right (fun rhs -> add_dep lhs_is_mem (adjust_tuple f_var rhs) rhs) |
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212 | (expr_list_of_expr e) (add_var lhs_is_mem lhs f_var g) |
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213 | in |
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214 | match rhs.expr_desc with |
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215 | | Expr_const _ -> g |
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216 | | Expr_fby (e1, e2) -> add_dep true lhs e2 (add_dep false lhs e1 g) |
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217 | | Expr_pre e -> add_dep true lhs e g |
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218 | | Expr_ident x -> add_var lhs_is_mem lhs x (add_clock lhs_is_mem lhs rhs.expr_clock g) |
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219 | a1daa793 | Temesghen Kahsai | | Expr_access (e1, d) |

220 | | Expr_power (e1, d) -> add_dep lhs_is_mem lhs e1 (add_dep lhs_is_mem lhs (expr_of_dimension d) g) |
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221 | e2068500 | Temesghen Kahsai | | Expr_array a -> List.fold_right (add_dep lhs_is_mem lhs) a g |

222 | | Expr_tuple t -> List.fold_right2 (fun l r -> add_dep lhs_is_mem [l] r) lhs t g |
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223 | | Expr_merge (c, hl) -> add_var lhs_is_mem lhs c (List.fold_right (fun (_, h) -> add_dep lhs_is_mem lhs h) hl g) |
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224 | | Expr_ite (c, t, e) -> add_dep lhs_is_mem lhs c (add_dep lhs_is_mem lhs t (add_dep lhs_is_mem lhs e g)) |
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225 | | Expr_arrow (e1, e2) -> add_dep lhs_is_mem lhs e2 (add_dep lhs_is_mem lhs e1 g) |
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226 | | Expr_when (e, c, _) -> add_dep lhs_is_mem lhs e (add_var lhs_is_mem lhs c g) |
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227 | | Expr_appl (f, e, None) -> |
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228 | if Basic_library.is_internal_fun f |
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229 | (* tuple component-wise dependency for internal operators *) |
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230 | then |
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231 | List.fold_right (add_dep lhs_is_mem lhs) (expr_list_of_expr e) g |
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232 | (* mashed up dependency for user-defined operators *) |
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233 | else |
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234 | mashup_appl_dependencies f e g |
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235 | | Expr_appl (f, e, Some c) -> |
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236 | mashup_appl_dependencies f e (add_dep lhs_is_mem lhs c g) |
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237 | in |
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238 | let g = |
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239 | List.fold_left |
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240 | (fun g lhs -> if ISet.mem lhs mems then add_vertices [lhs; mk_read_var lhs] g else add_vertices [lhs] g) g eq.eq_lhs in |
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241 | add_dep false eq.eq_lhs eq.eq_rhs (g, g') |
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242 | |||

243 | |||

244 | (* Returns the dependence graph for node [n] *) |
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245 | let dependence_graph mems inputs node_vars n = |
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246 | instance_var_cpt := 0; |
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247 | let g = new_graph (), new_graph () in |
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248 | (* Basic dependencies *) |
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249 | let g = List.fold_right (add_eq_dependencies mems inputs node_vars) (get_node_eqs n) g in |
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250 | g |
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251 | |||

252 | end |
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253 | |||

254 | module NodeDep = struct |
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255 | |||

256 | module ExprModule = |
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257 | struct |
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258 | type t = expr |
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259 | let compare = compare |
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260 | let hash n = Hashtbl.hash n |
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261 | let equal n1 n2 = n1 = n2 |
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262 | end |
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263 | |||

264 | module ESet = Set.Make(ExprModule) |
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265 | |||

266 | let rec get_expr_calls prednode expr = |
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267 | match expr.expr_desc with |
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268 | | Expr_const _ |
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269 | | Expr_ident _ -> ESet.empty |
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270 | | Expr_access (e, _) |
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271 | | Expr_power (e, _) -> get_expr_calls prednode e |
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272 | | Expr_array t |
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273 | | Expr_tuple t -> List.fold_right (fun x set -> ESet.union (get_expr_calls prednode x) set) t ESet.empty |
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274 | | Expr_merge (_,hl) -> List.fold_right (fun (_,h) set -> ESet.union (get_expr_calls prednode h) set) hl ESet.empty |
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275 | | Expr_fby (e1,e2) |
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276 | | Expr_arrow (e1,e2) -> ESet.union (get_expr_calls prednode e1) (get_expr_calls prednode e2) |
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277 | | Expr_ite (c, t, e) -> ESet.union (get_expr_calls prednode c) (ESet.union (get_expr_calls prednode t) (get_expr_calls prednode e)) |
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278 | | Expr_pre e |
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279 | | Expr_when (e,_,_) -> get_expr_calls prednode e |
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280 | | Expr_appl (id,e, _) -> |
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281 | if not (Basic_library.is_internal_fun id) && prednode id |
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282 | then ESet.add expr (get_expr_calls prednode e) |
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283 | else (get_expr_calls prednode e) |
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284 | |||

285 | let get_callee expr = |
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286 | match expr.expr_desc with |
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287 | | Expr_appl (id, args, _) -> Some (id, expr_list_of_expr args) |
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288 | | _ -> None |
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289 | |||

290 | let get_calls prednode eqs = |
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291 | let deps = |
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292 | List.fold_left |
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293 | (fun accu eq -> ESet.union accu (get_expr_calls prednode eq.eq_rhs)) |
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294 | ESet.empty |
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295 | eqs in |
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296 | ESet.elements deps |
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297 | |||

298 | let dependence_graph prog = |
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299 | let g = new_graph () in |
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300 | let g = List.fold_right |
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301 | (fun td accu -> (* for each node we add its dependencies *) |
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302 | match td.top_decl_desc with |
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303 | | Node nd -> |
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304 | (*Format.eprintf "Computing deps of node %s@.@?" nd.node_id; *) |
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305 | let accu = add_vertices [nd.node_id] accu in |
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306 | let deps = List.map (fun e -> fst (desome (get_callee e))) (get_calls (fun _ -> true) (get_node_eqs nd)) in |
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307 | (*Format.eprintf "%a@.@?" (Utils.fprintf_list ~sep:"@." Format.pp_print_string) deps; *) |
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308 | add_edges [nd.node_id] deps accu |
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309 | | _ -> assert false (* should not happen *) |
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310 | |||

311 | ) prog g in |
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312 | g |
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313 | |||

314 | let rec filter_static_inputs inputs args = |
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315 | match inputs, args with |
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316 | | [] , [] -> [] |
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317 | | v::vq, a::aq -> if v.var_dec_const then (dimension_of_expr a) :: filter_static_inputs vq aq else filter_static_inputs vq aq |
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318 | | _ -> assert false |
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319 | |||

320 | let compute_generic_calls prog = |
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321 | List.iter |
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322 | (fun td -> |
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323 | match td.top_decl_desc with |
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324 | | Node nd -> |
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325 | let prednode n = is_generic_node (Hashtbl.find node_table n) in |
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326 | nd.node_gencalls <- get_calls prednode (get_node_eqs nd) |
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327 | | _ -> () |
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328 | |||

329 | ) prog |
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330 | |||

331 | end |
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332 | |||

333 | module CycleDetection = struct |
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334 | |||

335 | (* ---- Look for cycles in a dependency graph *) |
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336 | module Cycles = Graph.Components.Make (IdentDepGraph) |
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337 | |||

338 | let mk_copy_var n id = |
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339 | let used name = |
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340 | (List.exists (fun v -> v.var_id = name) n.node_locals) |
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341 | || (List.exists (fun v -> v.var_id = name) n.node_inputs) |
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342 | || (List.exists (fun v -> v.var_id = name) n.node_outputs) |
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343 | in mk_new_name used id |
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344 | |||

345 | let mk_copy_eq n var = |
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346 | let var_decl = get_node_var var n in |
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347 | let cp_var = mk_copy_var n var in |
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348 | let expr = |
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349 | { expr_tag = Utils.new_tag (); |
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350 | expr_desc = Expr_ident var; |
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351 | expr_type = var_decl.var_type; |
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352 | expr_clock = var_decl.var_clock; |
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353 | expr_delay = Delay.new_var (); |
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354 | expr_annot = None; |
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355 | expr_loc = var_decl.var_loc } in |
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356 | { var_decl with var_id = cp_var; var_orig = false }, |
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357 | mkeq var_decl.var_loc ([cp_var], expr) |
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358 | |||

359 | let wrong_partition g partition = |
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360 | match partition with |
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361 | | [id] -> IdentDepGraph.mem_edge g id id |
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362 | | _::_::_ -> true |
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363 | | [] -> assert false |
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364 | |||

365 | (* Checks that the dependency graph [g] does not contain a cycle. Raises |
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366 | [Cycle partition] if the succession of dependencies [partition] forms a cycle *) |
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367 | let check_cycles g = |
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368 | let scc_l = Cycles.scc_list g in |
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369 | List.iter (fun partition -> |
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370 | if wrong_partition g partition then |
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371 | raise (Cycle partition) |
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372 | else () |
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373 | ) scc_l |
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374 | |||

375 | (* Creates the sub-graph of [g] restricted to vertices and edges in partition *) |
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376 | let copy_partition g partition = |
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377 | let copy_g = IdentDepGraph.create () in |
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378 | IdentDepGraph.iter_edges |
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379 | (fun src tgt -> |
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380 | if List.mem src partition && List.mem tgt partition |
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381 | then IdentDepGraph.add_edge copy_g src tgt) |
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382 | g |
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383 | |||

384 | |||

385 | (* Breaks dependency cycles in a graph [g] by inserting aux variables. |
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386 | [head] is a head of a non-trivial scc of [g]. |
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387 | In Lustre, this is legal only for mem/mem cycles *) |
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388 | let break_cycle head cp_head g = |
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389 | let succs = IdentDepGraph.succ g head in |
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390 | IdentDepGraph.add_edge g head cp_head; |
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391 | IdentDepGraph.add_edge g cp_head (ExprDep.mk_read_var head); |
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392 | List.iter |
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393 | (fun s -> |
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394 | IdentDepGraph.remove_edge g head s; |
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395 | IdentDepGraph.add_edge g s cp_head) |
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396 | succs |
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397 | |||

398 | (* Breaks cycles of the dependency graph [g] of memory variables [mems] |
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399 | belonging in node [node]. Returns: |
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400 | - a list of new auxiliary variable declarations |
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401 | - a list of new equations |
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402 | - a modified acyclic version of [g] |
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403 | *) |
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404 | let break_cycles node mems g = |
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405 | let (mem_eqs, non_mem_eqs) = List.partition (fun eq -> List.exists (fun v -> ISet.mem v mems) eq.eq_lhs) (get_node_eqs node) in |
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406 | let rec break vdecls mem_eqs g = |
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407 | let scc_l = Cycles.scc_list g in |
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408 | let wrong = List.filter (wrong_partition g) scc_l in |
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409 | match wrong with |
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410 | | [] -> (vdecls, non_mem_eqs@mem_eqs, g) |
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411 | | [head]::_ -> |
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412 | begin |
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413 | IdentDepGraph.remove_edge g head head; |
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414 | break vdecls mem_eqs g |
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415 | end |
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416 | | (head::part)::_ -> |
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417 | begin |
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418 | let vdecl_cp_head, cp_eq = mk_copy_eq node head in |
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419 | let pvar v = List.mem v part in |
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420 | let fvar v = if v = head then vdecl_cp_head.var_id else v in |
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421 | let mem_eqs' = List.map (eq_replace_rhs_var pvar fvar) mem_eqs in |
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422 | break_cycle head vdecl_cp_head.var_id g; |
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423 | break (vdecl_cp_head::vdecls) (cp_eq::mem_eqs') g |
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424 | end |
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425 | | _ -> assert false |
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426 | in break [] mem_eqs g |
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427 | |||

428 | end |
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429 | |||

430 | (* Module used to compute static disjunction of variables based upon their clocks. *) |
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431 | module Disjunction = |
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432 | struct |
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433 | module ClockedIdentModule = |
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434 | struct |
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435 | type t = var_decl |
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436 | let root_branch vdecl = Clocks.root vdecl.var_clock, Clocks.branch vdecl.var_clock |
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437 | let compare v1 v2 = compare (root_branch v2, v2.var_id) (root_branch v1, v1.var_id) |
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438 | end |
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439 | |||

440 | module CISet = Set.Make(ClockedIdentModule) |
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441 | |||

442 | (* map: var |-> list of disjoint vars, sorted in increasing branch length order, |
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443 | maybe removing shorter branches *) |
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444 | type disjoint_map = (ident, CISet.t) Hashtbl.t |
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445 | |||

446 | let pp_ciset fmt t = |
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447 | begin |
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448 | Format.fprintf fmt "{@ "; |
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449 | CISet.iter (fun s -> Format.fprintf fmt "%a@ " Printers.pp_var_name s) t; |
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450 | Format.fprintf fmt "}@." |
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451 | end |
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452 | |||

453 | let clock_disjoint_map vdecls = |
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454 | let map = Hashtbl.create 23 in |
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455 | begin |
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456 | List.iter |
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457 | (fun v1 -> let disj_v1 = |
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458 | List.fold_left |
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459 | (fun res v2 -> if Clocks.disjoint v1.var_clock v2.var_clock then CISet.add v2 res else res) |
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460 | CISet.empty |
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461 | vdecls in |
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462 | (* disjoint vdecls are stored in increasing branch length order *) |
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463 | Hashtbl.add map v1.var_id disj_v1) |
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464 | vdecls; |
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465 | (map : disjoint_map) |
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466 | end |
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467 | |||

468 | (* merge variables [v] and [v'] in disjunction [map]. Then: |
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469 | - the mapping v' becomes v' |-> (map v) inter (map v') |
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470 | - the mapping v |-> ... then disappears |
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471 | - other mappings become x |-> (map x) \ (if v in x then v else v') |
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472 | *) |
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473 | let merge_in_disjoint_map map v v' = |
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474 | begin |
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475 | Hashtbl.replace map v'.var_id (CISet.inter (Hashtbl.find map v.var_id) (Hashtbl.find map v'.var_id)); |
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476 | Hashtbl.remove map v.var_id; |
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477 | Hashtbl.iter (fun x map_x -> Hashtbl.replace map x (CISet.remove (if CISet.mem v map_x then v else v') map_x)) map; |
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478 | end |
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479 | |||

480 | (* replace variable [v] by [v'] in disjunction [map]. |
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481 | [v'] is a dead variable. Then: |
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482 | - the mapping v' becomes v' |-> (map v) |
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483 | - the mapping v |-> ... then disappears |
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484 | - all mappings become x |-> ((map x) \ { v}) union ({v'} if v in map x) |
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485 | *) |
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486 | let replace_in_disjoint_map map v v' = |
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487 | begin |
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488 | Hashtbl.replace map v'.var_id (Hashtbl.find map v.var_id); |
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489 | Hashtbl.remove map v.var_id; |
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490 | Hashtbl.iter (fun x mapx -> Hashtbl.replace map x (if CISet.mem v mapx then CISet.add v' (CISet.remove v mapx) else CISet.remove v' mapx)) map; |
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491 | end |
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492 | |||

493 | (* remove variable [v] in disjunction [map]. Then: |
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494 | - the mapping v |-> ... then disappears |
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495 | - all mappings become x |-> (map x) \ { v} |
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496 | *) |
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497 | let remove_in_disjoint_map map v = |
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498 | begin |
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499 | Hashtbl.remove map v.var_id; |
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500 | Hashtbl.iter (fun x mapx -> Hashtbl.replace map x (CISet.remove v mapx)) map; |
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501 | end |
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502 | |||

503 | let pp_disjoint_map fmt map = |
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504 | begin |
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505 | Format.fprintf fmt "{ /* disjoint map */@."; |
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506 | Hashtbl.iter (fun k v -> Format.fprintf fmt "%s # { %a }@." k (Utils.fprintf_list ~sep:", " Printers.pp_var_name) (CISet.elements v)) map; |
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507 | Format.fprintf fmt "}@." |
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508 | end |
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509 | end |
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510 | |||

511 | let pp_dep_graph fmt g = |
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512 | begin |
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513 | Format.fprintf fmt "{ /* graph */@."; |
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514 | IdentDepGraph.iter_edges (fun s t -> Format.fprintf fmt "%s -> %s@." s t) g; |
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515 | Format.fprintf fmt "}@." |
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516 | end |
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517 | |||

518 | let pp_error fmt trace = |
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519 | fprintf fmt "@.Causality error, cyclic data dependencies: %a@." |
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520 | (fprintf_list ~sep:", " pp_print_string) trace |
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521 | |||

522 | (* Merges elements of graph [g2] into graph [g1] *) |
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523 | let merge_with g1 g2 = |
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524 | begin |
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525 | IdentDepGraph.iter_vertex (fun v -> IdentDepGraph.add_vertex g1 v) g2; |
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526 | IdentDepGraph.iter_edges (fun s t -> IdentDepGraph.add_edge g1 s t) g2 |
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527 | end |
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528 | |||

529 | a1daa793 | Temesghen Kahsai | let world = "!!_world" |

530 | |||

531 | e2068500 | Temesghen Kahsai | let add_external_dependency outputs mems g = |

532 | begin |
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533 | a1daa793 | Temesghen Kahsai | IdentDepGraph.add_vertex g world; |

534 | ISet.iter (fun o -> IdentDepGraph.add_edge g world o) outputs; |
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535 | ISet.iter (fun m -> IdentDepGraph.add_edge g world m) mems; |
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536 | e2068500 | Temesghen Kahsai | end |

537 | |||

538 | let global_dependency node = |
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539 | let mems = ExprDep.node_memory_variables node in |
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540 | d50b0dc0 | Temesghen Kahsai | let inputs = |

541 | ISet.union |
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542 | (ExprDep.node_input_variables node) |
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543 | (ExprDep.node_constant_variables node) in |
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544 | e2068500 | Temesghen Kahsai | let outputs = ExprDep.node_output_variables node in |

545 | let node_vars = ExprDep.node_variables node in |
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546 | let (g_non_mems, g_mems) = ExprDep.dependence_graph mems inputs node_vars node in |
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547 | (*Format.eprintf "g_non_mems: %a" pp_dep_graph g_non_mems; |
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548 | Format.eprintf "g_mems: %a" pp_dep_graph g_mems;*) |
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549 | CycleDetection.check_cycles g_non_mems; |
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550 | let (vdecls', eqs', g_mems') = CycleDetection.break_cycles node mems g_mems in |
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551 | (*Format.eprintf "g_mems': %a" pp_dep_graph g_mems';*) |
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552 | begin |
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553 | merge_with g_non_mems g_mems'; |
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554 | add_external_dependency outputs mems g_non_mems; |
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555 | { node with node_stmts = List.map (fun eq -> Eq eq) eqs'; node_locals = vdecls'@node.node_locals }, |
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556 | g_non_mems |
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557 | end |
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558 | |||

559 | (* Local Variables: *) |
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560 | (* compile-command:"make -C .." *) |
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561 | (* End: *) |