1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- G N A T . P E R F E C T _ H A S H _ G E N E R A T O R S -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 2002-2011, AdaCore -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32with Ada.IO_Exceptions; use Ada.IO_Exceptions; 33with Ada.Characters.Handling; use Ada.Characters.Handling; 34with Ada.Directories; 35 36with GNAT.Heap_Sort_G; 37with GNAT.OS_Lib; use GNAT.OS_Lib; 38with GNAT.Table; 39 40package body GNAT.Perfect_Hash_Generators is 41 42 -- We are using the algorithm of J. Czech as described in Zbigniew J. 43 -- Czech, George Havas, and Bohdan S. Majewski ``An Optimal Algorithm for 44 -- Generating Minimal Perfect Hash Functions'', Information Processing 45 -- Letters, 43(1992) pp.257-264, Oct.1992 46 47 -- This minimal perfect hash function generator is based on random graphs 48 -- and produces a hash function of the form: 49 50 -- h (w) = (g (f1 (w)) + g (f2 (w))) mod m 51 52 -- where f1 and f2 are functions that map strings into integers, and g is 53 -- a function that maps integers into [0, m-1]. h can be order preserving. 54 -- For instance, let W = {w_0, ..., w_i, ..., w_m-1}, h can be defined 55 -- such that h (w_i) = i. 56 57 -- This algorithm defines two possible constructions of f1 and f2. Method 58 -- b) stores the hash function in less memory space at the expense of 59 -- greater CPU time. 60 61 -- a) fk (w) = sum (for i in 1 .. length (w)) (Tk (i, w (i))) mod n 62 63 -- size (Tk) = max (for w in W) (length (w)) * size (used char set) 64 65 -- b) fk (w) = sum (for i in 1 .. length (w)) (Tk (i) * w (i)) mod n 66 67 -- size (Tk) = max (for w in W) (length (w)) but the table lookups are 68 -- replaced by multiplications. 69 70 -- where Tk values are randomly generated. n is defined later on but the 71 -- algorithm recommends to use a value a little bit greater than 2m. Note 72 -- that for large values of m, the main memory space requirements comes 73 -- from the memory space for storing function g (>= 2m entries). 74 75 -- Random graphs are frequently used to solve difficult problems that do 76 -- not have polynomial solutions. This algorithm is based on a weighted 77 -- undirected graph. It comprises two steps: mapping and assignment. 78 79 -- In the mapping step, a graph G = (V, E) is constructed, where = {0, 1, 80 -- ..., n-1} and E = {(for w in W) (f1 (w), f2 (w))}. In order for the 81 -- assignment step to be successful, G has to be acyclic. To have a high 82 -- probability of generating an acyclic graph, n >= 2m. If it is not 83 -- acyclic, Tk have to be regenerated. 84 85 -- In the assignment step, the algorithm builds function g. As G is 86 -- acyclic, there is a vertex v1 with only one neighbor v2. Let w_i be 87 -- the word such that v1 = f1 (w_i) and v2 = f2 (w_i). Let g (v1) = 0 by 88 -- construction and g (v2) = (i - g (v1)) mod n (or h (i) - g (v1) mod n). 89 -- If word w_j is such that v2 = f1 (w_j) and v3 = f2 (w_j), g (v3) = (j - 90 -- g (v2)) mod (or to be general, (h (j) - g (v2)) mod n). If w_i has no 91 -- neighbor, then another vertex is selected. The algorithm traverses G to 92 -- assign values to all the vertices. It cannot assign a value to an 93 -- already assigned vertex as G is acyclic. 94 95 subtype Word_Id is Integer; 96 subtype Key_Id is Integer; 97 subtype Vertex_Id is Integer; 98 subtype Edge_Id is Integer; 99 subtype Table_Id is Integer; 100 101 No_Vertex : constant Vertex_Id := -1; 102 No_Edge : constant Edge_Id := -1; 103 No_Table : constant Table_Id := -1; 104 105 type Word_Type is new String_Access; 106 procedure Free_Word (W : in out Word_Type) renames Free; 107 function New_Word (S : String) return Word_Type; 108 109 procedure Resize_Word (W : in out Word_Type; Len : Natural); 110 -- Resize string W to have a length Len 111 112 type Key_Type is record 113 Edge : Edge_Id; 114 end record; 115 -- A key corresponds to an edge in the algorithm graph 116 117 type Vertex_Type is record 118 First : Edge_Id; 119 Last : Edge_Id; 120 end record; 121 -- A vertex can be involved in several edges. First and Last are the bounds 122 -- of an array of edges stored in a global edge table. 123 124 type Edge_Type is record 125 X : Vertex_Id; 126 Y : Vertex_Id; 127 Key : Key_Id; 128 end record; 129 -- An edge is a peer of vertices. In the algorithm, a key is associated to 130 -- an edge. 131 132 package WT is new GNAT.Table (Word_Type, Word_Id, 0, 32, 32); 133 package IT is new GNAT.Table (Integer, Integer, 0, 32, 32); 134 -- The two main tables. WT is used to store the words in their initial 135 -- version and in their reduced version (that is words reduced to their 136 -- significant characters). As an instance of GNAT.Table, WT does not 137 -- initialize string pointers to null. This initialization has to be done 138 -- manually when the table is allocated. IT is used to store several 139 -- tables of components containing only integers. 140 141 function Image (Int : Integer; W : Natural := 0) return String; 142 function Image (Str : String; W : Natural := 0) return String; 143 -- Return a string which includes string Str or integer Int preceded by 144 -- leading spaces if required by width W. 145 146 function Trim_Trailing_Nuls (Str : String) return String; 147 -- Return Str with trailing NUL characters removed 148 149 Output : File_Descriptor renames GNAT.OS_Lib.Standout; 150 -- Shortcuts 151 152 EOL : constant Character := ASCII.LF; 153 154 Max : constant := 78; 155 Last : Natural := 0; 156 Line : String (1 .. Max); 157 -- Use this line to provide buffered IO 158 159 procedure Add (C : Character); 160 procedure Add (S : String); 161 -- Add a character or a string in Line and update Last 162 163 procedure Put 164 (F : File_Descriptor; 165 S : String; 166 F1 : Natural; 167 L1 : Natural; 168 C1 : Natural; 169 F2 : Natural; 170 L2 : Natural; 171 C2 : Natural); 172 -- Write string S into file F as a element of an array of one or two 173 -- dimensions. Fk (resp. Lk and Ck) indicates the first (resp last and 174 -- current) index in the k-th dimension. If F1 = L1 the array is considered 175 -- as a one dimension array. This dimension is described by F2 and L2. This 176 -- routine takes care of all the parenthesis, spaces and commas needed to 177 -- format correctly the array. Moreover, the array is well indented and is 178 -- wrapped to fit in a 80 col line. When the line is full, the routine 179 -- writes it into file F. When the array is completed, the routine adds 180 -- semi-colon and writes the line into file F. 181 182 procedure New_Line (File : File_Descriptor); 183 -- Simulate Ada.Text_IO.New_Line with GNAT.OS_Lib 184 185 procedure Put (File : File_Descriptor; Str : String); 186 -- Simulate Ada.Text_IO.Put with GNAT.OS_Lib 187 188 procedure Put_Used_Char_Set (File : File_Descriptor; Title : String); 189 -- Output a title and a used character set 190 191 procedure Put_Int_Vector 192 (File : File_Descriptor; 193 Title : String; 194 Vector : Integer; 195 Length : Natural); 196 -- Output a title and a vector 197 198 procedure Put_Int_Matrix 199 (File : File_Descriptor; 200 Title : String; 201 Table : Table_Id; 202 Len_1 : Natural; 203 Len_2 : Natural); 204 -- Output a title and a matrix. When the matrix has only one non-empty 205 -- dimension (Len_2 = 0), output a vector. 206 207 procedure Put_Edges (File : File_Descriptor; Title : String); 208 -- Output a title and an edge table 209 210 procedure Put_Initial_Keys (File : File_Descriptor; Title : String); 211 -- Output a title and a key table 212 213 procedure Put_Reduced_Keys (File : File_Descriptor; Title : String); 214 -- Output a title and a key table 215 216 procedure Put_Vertex_Table (File : File_Descriptor; Title : String); 217 -- Output a title and a vertex table 218 219 function Ada_File_Base_Name (Pkg_Name : String) return String; 220 -- Return the base file name (i.e. without .ads/.adb extension) for an 221 -- Ada source file containing the named package, using the standard GNAT 222 -- file-naming convention. For example, if Pkg_Name is "Parent.Child", we 223 -- return "parent-child". 224 225 ---------------------------------- 226 -- Character Position Selection -- 227 ---------------------------------- 228 229 -- We reduce the maximum key size by selecting representative positions 230 -- in these keys. We build a matrix with one word per line. We fill the 231 -- remaining space of a line with ASCII.NUL. The heuristic selects the 232 -- position that induces the minimum number of collisions. If there are 233 -- collisions, select another position on the reduced key set responsible 234 -- of the collisions. Apply the heuristic until there is no more collision. 235 236 procedure Apply_Position_Selection; 237 -- Apply Position selection and build the reduced key table 238 239 procedure Parse_Position_Selection (Argument : String); 240 -- Parse Argument and compute the position set. Argument is list of 241 -- substrings separated by commas. Each substring represents a position 242 -- or a range of positions (like x-y). 243 244 procedure Select_Character_Set; 245 -- Define an optimized used character set like Character'Pos in order not 246 -- to allocate tables of 256 entries. 247 248 procedure Select_Char_Position; 249 -- Find a min char position set in order to reduce the max key length. The 250 -- heuristic selects the position that induces the minimum number of 251 -- collisions. If there are collisions, select another position on the 252 -- reduced key set responsible of the collisions. Apply the heuristic until 253 -- there is no collision. 254 255 ----------------------------- 256 -- Random Graph Generation -- 257 ----------------------------- 258 259 procedure Random (Seed : in out Natural); 260 -- Simulate Ada.Discrete_Numerics.Random 261 262 procedure Generate_Mapping_Table 263 (Tab : Table_Id; 264 L1 : Natural; 265 L2 : Natural; 266 Seed : in out Natural); 267 -- Random generation of the tables below. T is already allocated 268 269 procedure Generate_Mapping_Tables 270 (Opt : Optimization; 271 Seed : in out Natural); 272 -- Generate the mapping tables T1 and T2. They are used to define fk (w) = 273 -- sum (for i in 1 .. length (w)) (Tk (i, w (i))) mod n. Keys, NK and Chars 274 -- are used to compute the matrix size. 275 276 --------------------------- 277 -- Algorithm Computation -- 278 --------------------------- 279 280 procedure Compute_Edges_And_Vertices (Opt : Optimization); 281 -- Compute the edge and vertex tables. These are empty when a self loop is 282 -- detected (f1 (w) = f2 (w)). The edge table is sorted by X value and then 283 -- Y value. Keys is the key table and NK the number of keys. Chars is the 284 -- set of characters really used in Keys. NV is the number of vertices 285 -- recommended by the algorithm. T1 and T2 are the mapping tables needed to 286 -- compute f1 (w) and f2 (w). 287 288 function Acyclic return Boolean; 289 -- Return True when the graph is acyclic. Vertices is the current vertex 290 -- table and Edges the current edge table. 291 292 procedure Assign_Values_To_Vertices; 293 -- Execute the assignment step of the algorithm. Keys is the current key 294 -- table. Vertices and Edges represent the random graph. G is the result of 295 -- the assignment step such that: 296 -- h (w) = (g (f1 (w)) + g (f2 (w))) mod m 297 298 function Sum 299 (Word : Word_Type; 300 Table : Table_Id; 301 Opt : Optimization) return Natural; 302 -- For an optimization of CPU_Time return 303 -- fk (w) = sum (for i in 1 .. length (w)) (Tk (i, w (i))) mod n 304 -- For an optimization of Memory_Space return 305 -- fk (w) = sum (for i in 1 .. length (w)) (Tk (i) * w (i)) mod n 306 -- Here NV = n 307 308 ------------------------------- 309 -- Internal Table Management -- 310 ------------------------------- 311 312 function Allocate (N : Natural; S : Natural := 1) return Table_Id; 313 -- Allocate N * S ints from IT table 314 315 ---------- 316 -- Keys -- 317 ---------- 318 319 Keys : Table_Id := No_Table; 320 NK : Natural := 0; 321 -- NK : Number of Keys 322 323 function Initial (K : Key_Id) return Word_Id; 324 pragma Inline (Initial); 325 326 function Reduced (K : Key_Id) return Word_Id; 327 pragma Inline (Reduced); 328 329 function Get_Key (N : Key_Id) return Key_Type; 330 procedure Set_Key (N : Key_Id; Item : Key_Type); 331 -- Get or Set Nth element of Keys table 332 333 ------------------ 334 -- Char_Pos_Set -- 335 ------------------ 336 337 Char_Pos_Set : Table_Id := No_Table; 338 Char_Pos_Set_Len : Natural; 339 -- Character Selected Position Set 340 341 function Get_Char_Pos (P : Natural) return Natural; 342 procedure Set_Char_Pos (P : Natural; Item : Natural); 343 -- Get or Set the string position of the Pth selected character 344 345 ------------------- 346 -- Used_Char_Set -- 347 ------------------- 348 349 Used_Char_Set : Table_Id := No_Table; 350 Used_Char_Set_Len : Natural; 351 -- Used Character Set : Define a new character mapping. When all the 352 -- characters are not present in the keys, in order to reduce the size 353 -- of some tables, we redefine the character mapping. 354 355 function Get_Used_Char (C : Character) return Natural; 356 procedure Set_Used_Char (C : Character; Item : Natural); 357 358 ------------ 359 -- Tables -- 360 ------------ 361 362 T1 : Table_Id := No_Table; 363 T2 : Table_Id := No_Table; 364 T1_Len : Natural; 365 T2_Len : Natural; 366 -- T1 : Values table to compute F1 367 -- T2 : Values table to compute F2 368 369 function Get_Table (T : Integer; X, Y : Natural) return Natural; 370 procedure Set_Table (T : Integer; X, Y : Natural; Item : Natural); 371 372 ----------- 373 -- Graph -- 374 ----------- 375 376 G : Table_Id := No_Table; 377 G_Len : Natural; 378 -- Values table to compute G 379 380 NT : Natural := Default_Tries; 381 -- Number of tries running the algorithm before raising an error 382 383 function Get_Graph (N : Natural) return Integer; 384 procedure Set_Graph (N : Natural; Item : Integer); 385 -- Get or Set Nth element of graph 386 387 ----------- 388 -- Edges -- 389 ----------- 390 391 Edge_Size : constant := 3; 392 Edges : Table_Id := No_Table; 393 Edges_Len : Natural; 394 -- Edges : Edge table of the random graph G 395 396 function Get_Edges (F : Natural) return Edge_Type; 397 procedure Set_Edges (F : Natural; Item : Edge_Type); 398 399 -------------- 400 -- Vertices -- 401 -------------- 402 403 Vertex_Size : constant := 2; 404 405 Vertices : Table_Id := No_Table; 406 -- Vertex table of the random graph G 407 408 NV : Natural; 409 -- Number of Vertices 410 411 function Get_Vertices (F : Natural) return Vertex_Type; 412 procedure Set_Vertices (F : Natural; Item : Vertex_Type); 413 -- Comments needed ??? 414 415 K2V : Float; 416 -- Ratio between Keys and Vertices (parameter of Czech's algorithm) 417 418 Opt : Optimization; 419 -- Optimization mode (memory vs CPU) 420 421 Max_Key_Len : Natural := 0; 422 Min_Key_Len : Natural := 0; 423 -- Maximum and minimum of all the word length 424 425 S : Natural; 426 -- Seed 427 428 function Type_Size (L : Natural) return Natural; 429 -- Given the last L of an unsigned integer type T, return its size 430 431 ------------- 432 -- Acyclic -- 433 ------------- 434 435 function Acyclic return Boolean is 436 Marks : array (0 .. NV - 1) of Vertex_Id := (others => No_Vertex); 437 438 function Traverse (Edge : Edge_Id; Mark : Vertex_Id) return Boolean; 439 -- Propagate Mark from X to Y. X is already marked. Mark Y and propagate 440 -- it to the edges of Y except the one representing the same key. Return 441 -- False when Y is marked with Mark. 442 443 -------------- 444 -- Traverse -- 445 -------------- 446 447 function Traverse (Edge : Edge_Id; Mark : Vertex_Id) return Boolean is 448 E : constant Edge_Type := Get_Edges (Edge); 449 K : constant Key_Id := E.Key; 450 Y : constant Vertex_Id := E.Y; 451 M : constant Vertex_Id := Marks (E.Y); 452 V : Vertex_Type; 453 454 begin 455 if M = Mark then 456 return False; 457 458 elsif M = No_Vertex then 459 Marks (Y) := Mark; 460 V := Get_Vertices (Y); 461 462 for J in V.First .. V.Last loop 463 464 -- Do not propagate to the edge representing the same key 465 466 if Get_Edges (J).Key /= K 467 and then not Traverse (J, Mark) 468 then 469 return False; 470 end if; 471 end loop; 472 end if; 473 474 return True; 475 end Traverse; 476 477 Edge : Edge_Type; 478 479 -- Start of processing for Acyclic 480 481 begin 482 -- Edges valid range is 483 484 for J in 1 .. Edges_Len - 1 loop 485 486 Edge := Get_Edges (J); 487 488 -- Mark X of E when it has not been already done 489 490 if Marks (Edge.X) = No_Vertex then 491 Marks (Edge.X) := Edge.X; 492 end if; 493 494 -- Traverse E when this has not already been done 495 496 if Marks (Edge.Y) = No_Vertex 497 and then not Traverse (J, Edge.X) 498 then 499 return False; 500 end if; 501 end loop; 502 503 return True; 504 end Acyclic; 505 506 ------------------------ 507 -- Ada_File_Base_Name -- 508 ------------------------ 509 510 function Ada_File_Base_Name (Pkg_Name : String) return String is 511 begin 512 -- Convert to lower case, then replace '.' with '-' 513 514 return Result : String := To_Lower (Pkg_Name) do 515 for J in Result'Range loop 516 if Result (J) = '.' then 517 Result (J) := '-'; 518 end if; 519 end loop; 520 end return; 521 end Ada_File_Base_Name; 522 523 --------- 524 -- Add -- 525 --------- 526 527 procedure Add (C : Character) is 528 pragma Assert (C /= ASCII.NUL); 529 begin 530 Line (Last + 1) := C; 531 Last := Last + 1; 532 end Add; 533 534 --------- 535 -- Add -- 536 --------- 537 538 procedure Add (S : String) is 539 Len : constant Natural := S'Length; 540 begin 541 for J in S'Range loop 542 pragma Assert (S (J) /= ASCII.NUL); 543 null; 544 end loop; 545 546 Line (Last + 1 .. Last + Len) := S; 547 Last := Last + Len; 548 end Add; 549 550 -------------- 551 -- Allocate -- 552 -------------- 553 554 function Allocate (N : Natural; S : Natural := 1) return Table_Id is 555 L : constant Integer := IT.Last; 556 begin 557 IT.Set_Last (L + N * S); 558 559 -- Initialize, so debugging printouts don't trip over uninitialized 560 -- components. 561 562 for J in L + 1 .. IT.Last loop 563 IT.Table (J) := -1; 564 end loop; 565 566 return L + 1; 567 end Allocate; 568 569 ------------------------------ 570 -- Apply_Position_Selection -- 571 ------------------------------ 572 573 procedure Apply_Position_Selection is 574 begin 575 for J in 0 .. NK - 1 loop 576 declare 577 IW : constant String := WT.Table (Initial (J)).all; 578 RW : String (1 .. IW'Length) := (others => ASCII.NUL); 579 N : Natural := IW'First - 1; 580 581 begin 582 -- Select the characters of Word included in the position 583 -- selection. 584 585 for C in 0 .. Char_Pos_Set_Len - 1 loop 586 exit when IW (Get_Char_Pos (C)) = ASCII.NUL; 587 N := N + 1; 588 RW (N) := IW (Get_Char_Pos (C)); 589 end loop; 590 591 -- Build the new table with the reduced word. Be careful 592 -- to deallocate the old version to avoid memory leaks. 593 594 Free_Word (WT.Table (Reduced (J))); 595 WT.Table (Reduced (J)) := New_Word (RW); 596 Set_Key (J, (Edge => No_Edge)); 597 end; 598 end loop; 599 end Apply_Position_Selection; 600 601 ------------------------------- 602 -- Assign_Values_To_Vertices -- 603 ------------------------------- 604 605 procedure Assign_Values_To_Vertices is 606 X : Vertex_Id; 607 608 procedure Assign (X : Vertex_Id); 609 -- Execute assignment on X's neighbors except the vertex that we are 610 -- coming from which is already assigned. 611 612 ------------ 613 -- Assign -- 614 ------------ 615 616 procedure Assign (X : Vertex_Id) is 617 E : Edge_Type; 618 V : constant Vertex_Type := Get_Vertices (X); 619 620 begin 621 for J in V.First .. V.Last loop 622 E := Get_Edges (J); 623 624 if Get_Graph (E.Y) = -1 then 625 Set_Graph (E.Y, (E.Key - Get_Graph (X)) mod NK); 626 Assign (E.Y); 627 end if; 628 end loop; 629 end Assign; 630 631 -- Start of processing for Assign_Values_To_Vertices 632 633 begin 634 -- Value -1 denotes an uninitialized value as it is supposed to 635 -- be in the range 0 .. NK. 636 637 if G = No_Table then 638 G_Len := NV; 639 G := Allocate (G_Len, 1); 640 end if; 641 642 for J in 0 .. G_Len - 1 loop 643 Set_Graph (J, -1); 644 end loop; 645 646 for K in 0 .. NK - 1 loop 647 X := Get_Edges (Get_Key (K).Edge).X; 648 649 if Get_Graph (X) = -1 then 650 Set_Graph (X, 0); 651 Assign (X); 652 end if; 653 end loop; 654 655 for J in 0 .. G_Len - 1 loop 656 if Get_Graph (J) = -1 then 657 Set_Graph (J, 0); 658 end if; 659 end loop; 660 661 if Verbose then 662 Put_Int_Vector (Output, "Assign Values To Vertices", G, G_Len); 663 end if; 664 end Assign_Values_To_Vertices; 665 666 ------------- 667 -- Compute -- 668 ------------- 669 670 procedure Compute (Position : String := Default_Position) is 671 Success : Boolean := False; 672 673 begin 674 if NK = 0 then 675 raise Program_Error with "keywords set cannot be empty"; 676 end if; 677 678 if Verbose then 679 Put_Initial_Keys (Output, "Initial Key Table"); 680 end if; 681 682 if Position'Length /= 0 then 683 Parse_Position_Selection (Position); 684 else 685 Select_Char_Position; 686 end if; 687 688 if Verbose then 689 Put_Int_Vector 690 (Output, "Char Position Set", Char_Pos_Set, Char_Pos_Set_Len); 691 end if; 692 693 Apply_Position_Selection; 694 695 if Verbose then 696 Put_Reduced_Keys (Output, "Reduced Keys Table"); 697 end if; 698 699 Select_Character_Set; 700 701 if Verbose then 702 Put_Used_Char_Set (Output, "Character Position Table"); 703 end if; 704 705 -- Perform Czech's algorithm 706 707 for J in 1 .. NT loop 708 Generate_Mapping_Tables (Opt, S); 709 Compute_Edges_And_Vertices (Opt); 710 711 -- When graph is not empty (no self-loop from previous operation) and 712 -- not acyclic. 713 714 if 0 < Edges_Len and then Acyclic then 715 Success := True; 716 exit; 717 end if; 718 end loop; 719 720 if not Success then 721 raise Too_Many_Tries; 722 end if; 723 724 Assign_Values_To_Vertices; 725 end Compute; 726 727 -------------------------------- 728 -- Compute_Edges_And_Vertices -- 729 -------------------------------- 730 731 procedure Compute_Edges_And_Vertices (Opt : Optimization) is 732 X : Natural; 733 Y : Natural; 734 Key : Key_Type; 735 Edge : Edge_Type; 736 Vertex : Vertex_Type; 737 Not_Acyclic : Boolean := False; 738 739 procedure Move (From : Natural; To : Natural); 740 function Lt (L, R : Natural) return Boolean; 741 -- Subprograms needed for GNAT.Heap_Sort_G 742 743 -------- 744 -- Lt -- 745 -------- 746 747 function Lt (L, R : Natural) return Boolean is 748 EL : constant Edge_Type := Get_Edges (L); 749 ER : constant Edge_Type := Get_Edges (R); 750 begin 751 return EL.X < ER.X or else (EL.X = ER.X and then EL.Y < ER.Y); 752 end Lt; 753 754 ---------- 755 -- Move -- 756 ---------- 757 758 procedure Move (From : Natural; To : Natural) is 759 begin 760 Set_Edges (To, Get_Edges (From)); 761 end Move; 762 763 package Sorting is new GNAT.Heap_Sort_G (Move, Lt); 764 765 -- Start of processing for Compute_Edges_And_Vertices 766 767 begin 768 -- We store edges from 1 to 2 * NK and leave zero alone in order to use 769 -- GNAT.Heap_Sort_G. 770 771 Edges_Len := 2 * NK + 1; 772 773 if Edges = No_Table then 774 Edges := Allocate (Edges_Len, Edge_Size); 775 end if; 776 777 if Vertices = No_Table then 778 Vertices := Allocate (NV, Vertex_Size); 779 end if; 780 781 for J in 0 .. NV - 1 loop 782 Set_Vertices (J, (No_Vertex, No_Vertex - 1)); 783 end loop; 784 785 -- For each w, X = f1 (w) and Y = f2 (w) 786 787 for J in 0 .. NK - 1 loop 788 Key := Get_Key (J); 789 Key.Edge := No_Edge; 790 Set_Key (J, Key); 791 792 X := Sum (WT.Table (Reduced (J)), T1, Opt); 793 Y := Sum (WT.Table (Reduced (J)), T2, Opt); 794 795 -- Discard T1 and T2 as soon as we discover a self loop 796 797 if X = Y then 798 Not_Acyclic := True; 799 exit; 800 end if; 801 802 -- We store (X, Y) and (Y, X) to ease assignment step 803 804 Set_Edges (2 * J + 1, (X, Y, J)); 805 Set_Edges (2 * J + 2, (Y, X, J)); 806 end loop; 807 808 -- Return an empty graph when self loop detected 809 810 if Not_Acyclic then 811 Edges_Len := 0; 812 813 else 814 if Verbose then 815 Put_Edges (Output, "Unsorted Edge Table"); 816 Put_Int_Matrix (Output, "Function Table 1", T1, 817 T1_Len, T2_Len); 818 Put_Int_Matrix (Output, "Function Table 2", T2, 819 T1_Len, T2_Len); 820 end if; 821 822 -- Enforce consistency between edges and keys. Construct Vertices and 823 -- compute the list of neighbors of a vertex First .. Last as Edges 824 -- is sorted by X and then Y. To compute the neighbor list, sort the 825 -- edges. 826 827 Sorting.Sort (Edges_Len - 1); 828 829 if Verbose then 830 Put_Edges (Output, "Sorted Edge Table"); 831 Put_Int_Matrix (Output, "Function Table 1", T1, 832 T1_Len, T2_Len); 833 Put_Int_Matrix (Output, "Function Table 2", T2, 834 T1_Len, T2_Len); 835 end if; 836 837 -- Edges valid range is 1 .. 2 * NK 838 839 for E in 1 .. Edges_Len - 1 loop 840 Edge := Get_Edges (E); 841 Key := Get_Key (Edge.Key); 842 843 if Key.Edge = No_Edge then 844 Key.Edge := E; 845 Set_Key (Edge.Key, Key); 846 end if; 847 848 Vertex := Get_Vertices (Edge.X); 849 850 if Vertex.First = No_Edge then 851 Vertex.First := E; 852 end if; 853 854 Vertex.Last := E; 855 Set_Vertices (Edge.X, Vertex); 856 end loop; 857 858 if Verbose then 859 Put_Reduced_Keys (Output, "Key Table"); 860 Put_Edges (Output, "Edge Table"); 861 Put_Vertex_Table (Output, "Vertex Table"); 862 end if; 863 end if; 864 end Compute_Edges_And_Vertices; 865 866 ------------ 867 -- Define -- 868 ------------ 869 870 procedure Define 871 (Name : Table_Name; 872 Item_Size : out Natural; 873 Length_1 : out Natural; 874 Length_2 : out Natural) 875 is 876 begin 877 case Name is 878 when Character_Position => 879 Item_Size := 8; 880 Length_1 := Char_Pos_Set_Len; 881 Length_2 := 0; 882 883 when Used_Character_Set => 884 Item_Size := 8; 885 Length_1 := 256; 886 Length_2 := 0; 887 888 when Function_Table_1 889 | Function_Table_2 => 890 Item_Size := Type_Size (NV); 891 Length_1 := T1_Len; 892 Length_2 := T2_Len; 893 894 when Graph_Table => 895 Item_Size := Type_Size (NK); 896 Length_1 := NV; 897 Length_2 := 0; 898 end case; 899 end Define; 900 901 -------------- 902 -- Finalize -- 903 -------------- 904 905 procedure Finalize is 906 begin 907 if Verbose then 908 Put (Output, "Finalize"); 909 New_Line (Output); 910 end if; 911 912 -- Deallocate all the WT components (both initial and reduced ones) to 913 -- avoid memory leaks. 914 915 for W in 0 .. WT.Last loop 916 917 -- Note: WT.Table (NK) is a temporary variable, do not free it since 918 -- this would cause a double free. 919 920 if W /= NK then 921 Free_Word (WT.Table (W)); 922 end if; 923 end loop; 924 925 WT.Release; 926 IT.Release; 927 928 -- Reset all variables for next usage 929 930 Keys := No_Table; 931 932 Char_Pos_Set := No_Table; 933 Char_Pos_Set_Len := 0; 934 935 Used_Char_Set := No_Table; 936 Used_Char_Set_Len := 0; 937 938 T1 := No_Table; 939 T2 := No_Table; 940 941 T1_Len := 0; 942 T2_Len := 0; 943 944 G := No_Table; 945 G_Len := 0; 946 947 Edges := No_Table; 948 Edges_Len := 0; 949 950 Vertices := No_Table; 951 NV := 0; 952 953 NK := 0; 954 Max_Key_Len := 0; 955 Min_Key_Len := 0; 956 end Finalize; 957 958 ---------------------------- 959 -- Generate_Mapping_Table -- 960 ---------------------------- 961 962 procedure Generate_Mapping_Table 963 (Tab : Integer; 964 L1 : Natural; 965 L2 : Natural; 966 Seed : in out Natural) 967 is 968 begin 969 for J in 0 .. L1 - 1 loop 970 for K in 0 .. L2 - 1 loop 971 Random (Seed); 972 Set_Table (Tab, J, K, Seed mod NV); 973 end loop; 974 end loop; 975 end Generate_Mapping_Table; 976 977 ----------------------------- 978 -- Generate_Mapping_Tables -- 979 ----------------------------- 980 981 procedure Generate_Mapping_Tables 982 (Opt : Optimization; 983 Seed : in out Natural) 984 is 985 begin 986 -- If T1 and T2 are already allocated no need to do it twice. Reuse them 987 -- as their size has not changed. 988 989 if T1 = No_Table and then T2 = No_Table then 990 declare 991 Used_Char_Last : Natural := 0; 992 Used_Char : Natural; 993 994 begin 995 if Opt = CPU_Time then 996 for P in reverse Character'Range loop 997 Used_Char := Get_Used_Char (P); 998 if Used_Char /= 0 then 999 Used_Char_Last := Used_Char; 1000 exit; 1001 end if; 1002 end loop; 1003 end if; 1004 1005 T1_Len := Char_Pos_Set_Len; 1006 T2_Len := Used_Char_Last + 1; 1007 T1 := Allocate (T1_Len * T2_Len); 1008 T2 := Allocate (T1_Len * T2_Len); 1009 end; 1010 end if; 1011 1012 Generate_Mapping_Table (T1, T1_Len, T2_Len, Seed); 1013 Generate_Mapping_Table (T2, T1_Len, T2_Len, Seed); 1014 1015 if Verbose then 1016 Put_Used_Char_Set (Output, "Used Character Set"); 1017 Put_Int_Matrix (Output, "Function Table 1", T1, 1018 T1_Len, T2_Len); 1019 Put_Int_Matrix (Output, "Function Table 2", T2, 1020 T1_Len, T2_Len); 1021 end if; 1022 end Generate_Mapping_Tables; 1023 1024 ------------------ 1025 -- Get_Char_Pos -- 1026 ------------------ 1027 1028 function Get_Char_Pos (P : Natural) return Natural is 1029 N : constant Natural := Char_Pos_Set + P; 1030 begin 1031 return IT.Table (N); 1032 end Get_Char_Pos; 1033 1034 --------------- 1035 -- Get_Edges -- 1036 --------------- 1037 1038 function Get_Edges (F : Natural) return Edge_Type is 1039 N : constant Natural := Edges + (F * Edge_Size); 1040 E : Edge_Type; 1041 begin 1042 E.X := IT.Table (N); 1043 E.Y := IT.Table (N + 1); 1044 E.Key := IT.Table (N + 2); 1045 return E; 1046 end Get_Edges; 1047 1048 --------------- 1049 -- Get_Graph -- 1050 --------------- 1051 1052 function Get_Graph (N : Natural) return Integer is 1053 begin 1054 return IT.Table (G + N); 1055 end Get_Graph; 1056 1057 ------------- 1058 -- Get_Key -- 1059 ------------- 1060 1061 function Get_Key (N : Key_Id) return Key_Type is 1062 K : Key_Type; 1063 begin 1064 K.Edge := IT.Table (Keys + N); 1065 return K; 1066 end Get_Key; 1067 1068 --------------- 1069 -- Get_Table -- 1070 --------------- 1071 1072 function Get_Table (T : Integer; X, Y : Natural) return Natural is 1073 N : constant Natural := T + (Y * T1_Len) + X; 1074 begin 1075 return IT.Table (N); 1076 end Get_Table; 1077 1078 ------------------- 1079 -- Get_Used_Char -- 1080 ------------------- 1081 1082 function Get_Used_Char (C : Character) return Natural is 1083 N : constant Natural := Used_Char_Set + Character'Pos (C); 1084 begin 1085 return IT.Table (N); 1086 end Get_Used_Char; 1087 1088 ------------------ 1089 -- Get_Vertices -- 1090 ------------------ 1091 1092 function Get_Vertices (F : Natural) return Vertex_Type is 1093 N : constant Natural := Vertices + (F * Vertex_Size); 1094 V : Vertex_Type; 1095 begin 1096 V.First := IT.Table (N); 1097 V.Last := IT.Table (N + 1); 1098 return V; 1099 end Get_Vertices; 1100 1101 ----------- 1102 -- Image -- 1103 ----------- 1104 1105 function Image (Int : Integer; W : Natural := 0) return String is 1106 B : String (1 .. 32); 1107 L : Natural := 0; 1108 1109 procedure Img (V : Natural); 1110 -- Compute image of V into B, starting at B (L), incrementing L 1111 1112 --------- 1113 -- Img -- 1114 --------- 1115 1116 procedure Img (V : Natural) is 1117 begin 1118 if V > 9 then 1119 Img (V / 10); 1120 end if; 1121 1122 L := L + 1; 1123 B (L) := Character'Val ((V mod 10) + Character'Pos ('0')); 1124 end Img; 1125 1126 -- Start of processing for Image 1127 1128 begin 1129 if Int < 0 then 1130 L := L + 1; 1131 B (L) := '-'; 1132 Img (-Int); 1133 else 1134 Img (Int); 1135 end if; 1136 1137 return Image (B (1 .. L), W); 1138 end Image; 1139 1140 ----------- 1141 -- Image -- 1142 ----------- 1143 1144 function Image (Str : String; W : Natural := 0) return String is 1145 Len : constant Natural := Str'Length; 1146 Max : Natural := Len; 1147 1148 begin 1149 if Max < W then 1150 Max := W; 1151 end if; 1152 1153 declare 1154 Buf : String (1 .. Max) := (1 .. Max => ' '); 1155 1156 begin 1157 for J in 0 .. Len - 1 loop 1158 Buf (Max - Len + 1 + J) := Str (Str'First + J); 1159 end loop; 1160 1161 return Buf; 1162 end; 1163 end Image; 1164 1165 ------------- 1166 -- Initial -- 1167 ------------- 1168 1169 function Initial (K : Key_Id) return Word_Id is 1170 begin 1171 return K; 1172 end Initial; 1173 1174 ---------------- 1175 -- Initialize -- 1176 ---------------- 1177 1178 procedure Initialize 1179 (Seed : Natural; 1180 K_To_V : Float := Default_K_To_V; 1181 Optim : Optimization := Memory_Space; 1182 Tries : Positive := Default_Tries) 1183 is 1184 begin 1185 if Verbose then 1186 Put (Output, "Initialize"); 1187 New_Line (Output); 1188 end if; 1189 1190 -- Deallocate the part of the table concerning the reduced words. 1191 -- Initial words are already present in the table. We may have reduced 1192 -- words already there because a previous computation failed. We are 1193 -- currently retrying and the reduced words have to be deallocated. 1194 1195 for W in Reduced (0) .. WT.Last loop 1196 Free_Word (WT.Table (W)); 1197 end loop; 1198 1199 IT.Init; 1200 1201 -- Initialize of computation variables 1202 1203 Keys := No_Table; 1204 1205 Char_Pos_Set := No_Table; 1206 Char_Pos_Set_Len := 0; 1207 1208 Used_Char_Set := No_Table; 1209 Used_Char_Set_Len := 0; 1210 1211 T1 := No_Table; 1212 T2 := No_Table; 1213 1214 T1_Len := 0; 1215 T2_Len := 0; 1216 1217 G := No_Table; 1218 G_Len := 0; 1219 1220 Edges := No_Table; 1221 Edges_Len := 0; 1222 1223 Vertices := No_Table; 1224 NV := 0; 1225 1226 S := Seed; 1227 K2V := K_To_V; 1228 Opt := Optim; 1229 NT := Tries; 1230 1231 if K2V <= 2.0 then 1232 raise Program_Error with "K to V ratio cannot be lower than 2.0"; 1233 end if; 1234 1235 -- Do not accept a value of K2V too close to 2.0 such that once 1236 -- rounded up, NV = 2 * NK because the algorithm would not converge. 1237 1238 NV := Natural (Float (NK) * K2V); 1239 if NV <= 2 * NK then 1240 NV := 2 * NK + 1; 1241 end if; 1242 1243 Keys := Allocate (NK); 1244 1245 -- Resize initial words to have all of them at the same size 1246 -- (so the size of the largest one). 1247 1248 for K in 0 .. NK - 1 loop 1249 Resize_Word (WT.Table (Initial (K)), Max_Key_Len); 1250 end loop; 1251 1252 -- Allocated the table to store the reduced words. As WT is a 1253 -- GNAT.Table (using C memory management), pointers have to be 1254 -- explicitly initialized to null. 1255 1256 WT.Set_Last (Reduced (NK - 1)); 1257 1258 -- Note: Reduced (0) = NK + 1 1259 1260 WT.Table (NK) := null; 1261 1262 for W in 0 .. NK - 1 loop 1263 WT.Table (Reduced (W)) := null; 1264 end loop; 1265 end Initialize; 1266 1267 ------------ 1268 -- Insert -- 1269 ------------ 1270 1271 procedure Insert (Value : String) is 1272 Len : constant Natural := Value'Length; 1273 1274 begin 1275 if Verbose then 1276 Put (Output, "Inserting """ & Value & """"); 1277 New_Line (Output); 1278 end if; 1279 1280 for J in Value'Range loop 1281 pragma Assert (Value (J) /= ASCII.NUL); 1282 null; 1283 end loop; 1284 1285 WT.Set_Last (NK); 1286 WT.Table (NK) := New_Word (Value); 1287 NK := NK + 1; 1288 1289 if Max_Key_Len < Len then 1290 Max_Key_Len := Len; 1291 end if; 1292 1293 if Min_Key_Len = 0 or else Len < Min_Key_Len then 1294 Min_Key_Len := Len; 1295 end if; 1296 end Insert; 1297 1298 -------------- 1299 -- New_Line -- 1300 -------------- 1301 1302 procedure New_Line (File : File_Descriptor) is 1303 begin 1304 if Write (File, EOL'Address, 1) /= 1 then 1305 raise Program_Error; 1306 end if; 1307 end New_Line; 1308 1309 -------------- 1310 -- New_Word -- 1311 -------------- 1312 1313 function New_Word (S : String) return Word_Type is 1314 begin 1315 return new String'(S); 1316 end New_Word; 1317 1318 ------------------------------ 1319 -- Parse_Position_Selection -- 1320 ------------------------------ 1321 1322 procedure Parse_Position_Selection (Argument : String) is 1323 N : Natural := Argument'First; 1324 L : constant Natural := Argument'Last; 1325 M : constant Natural := Max_Key_Len; 1326 1327 T : array (1 .. M) of Boolean := (others => False); 1328 1329 function Parse_Index return Natural; 1330 -- Parse argument starting at index N to find an index 1331 1332 ----------------- 1333 -- Parse_Index -- 1334 ----------------- 1335 1336 function Parse_Index return Natural is 1337 C : Character := Argument (N); 1338 V : Natural := 0; 1339 1340 begin 1341 if C = '$' then 1342 N := N + 1; 1343 return M; 1344 end if; 1345 1346 if C not in '0' .. '9' then 1347 raise Program_Error with "cannot read position argument"; 1348 end if; 1349 1350 while C in '0' .. '9' loop 1351 V := V * 10 + (Character'Pos (C) - Character'Pos ('0')); 1352 N := N + 1; 1353 exit when L < N; 1354 C := Argument (N); 1355 end loop; 1356 1357 return V; 1358 end Parse_Index; 1359 1360 -- Start of processing for Parse_Position_Selection 1361 1362 begin 1363 -- Empty specification means all the positions 1364 1365 if L < N then 1366 Char_Pos_Set_Len := M; 1367 Char_Pos_Set := Allocate (Char_Pos_Set_Len); 1368 1369 for C in 0 .. Char_Pos_Set_Len - 1 loop 1370 Set_Char_Pos (C, C + 1); 1371 end loop; 1372 1373 else 1374 loop 1375 declare 1376 First, Last : Natural; 1377 1378 begin 1379 First := Parse_Index; 1380 Last := First; 1381 1382 -- Detect a range 1383 1384 if N <= L and then Argument (N) = '-' then 1385 N := N + 1; 1386 Last := Parse_Index; 1387 end if; 1388 1389 -- Include the positions in the selection 1390 1391 for J in First .. Last loop 1392 T (J) := True; 1393 end loop; 1394 end; 1395 1396 exit when L < N; 1397 1398 if Argument (N) /= ',' then 1399 raise Program_Error with "cannot read position argument"; 1400 end if; 1401 1402 N := N + 1; 1403 end loop; 1404 1405 -- Compute position selection length 1406 1407 N := 0; 1408 for J in T'Range loop 1409 if T (J) then 1410 N := N + 1; 1411 end if; 1412 end loop; 1413 1414 -- Fill position selection 1415 1416 Char_Pos_Set_Len := N; 1417 Char_Pos_Set := Allocate (Char_Pos_Set_Len); 1418 1419 N := 0; 1420 for J in T'Range loop 1421 if T (J) then 1422 Set_Char_Pos (N, J); 1423 N := N + 1; 1424 end if; 1425 end loop; 1426 end if; 1427 end Parse_Position_Selection; 1428 1429 ------------- 1430 -- Produce -- 1431 ------------- 1432 1433 procedure Produce 1434 (Pkg_Name : String := Default_Pkg_Name; 1435 Use_Stdout : Boolean := False) 1436 is 1437 File : File_Descriptor := Standout; 1438 1439 Status : Boolean; 1440 -- For call to Close 1441 1442 function Array_Img (N, T, R1 : String; R2 : String := "") return String; 1443 -- Return string "N : constant array (R1[, R2]) of T;" 1444 1445 function Range_Img (F, L : Natural; T : String := "") return String; 1446 -- Return string "[T range ]F .. L" 1447 1448 function Type_Img (L : Natural) return String; 1449 -- Return the larger unsigned type T such that T'Last < L 1450 1451 --------------- 1452 -- Array_Img -- 1453 --------------- 1454 1455 function Array_Img 1456 (N, T, R1 : String; 1457 R2 : String := "") return String 1458 is 1459 begin 1460 Last := 0; 1461 Add (" "); 1462 Add (N); 1463 Add (" : constant array ("); 1464 Add (R1); 1465 1466 if R2 /= "" then 1467 Add (", "); 1468 Add (R2); 1469 end if; 1470 1471 Add (") of "); 1472 Add (T); 1473 Add (" :="); 1474 return Line (1 .. Last); 1475 end Array_Img; 1476 1477 --------------- 1478 -- Range_Img -- 1479 --------------- 1480 1481 function Range_Img (F, L : Natural; T : String := "") return String is 1482 FI : constant String := Image (F); 1483 FL : constant Natural := FI'Length; 1484 LI : constant String := Image (L); 1485 LL : constant Natural := LI'Length; 1486 TL : constant Natural := T'Length; 1487 RI : String (1 .. TL + 7 + FL + 4 + LL); 1488 Len : Natural := 0; 1489 1490 begin 1491 if TL /= 0 then 1492 RI (Len + 1 .. Len + TL) := T; 1493 Len := Len + TL; 1494 RI (Len + 1 .. Len + 7) := " range "; 1495 Len := Len + 7; 1496 end if; 1497 1498 RI (Len + 1 .. Len + FL) := FI; 1499 Len := Len + FL; 1500 RI (Len + 1 .. Len + 4) := " .. "; 1501 Len := Len + 4; 1502 RI (Len + 1 .. Len + LL) := LI; 1503 Len := Len + LL; 1504 return RI (1 .. Len); 1505 end Range_Img; 1506 1507 -------------- 1508 -- Type_Img -- 1509 -------------- 1510 1511 function Type_Img (L : Natural) return String is 1512 S : constant String := Image (Type_Size (L)); 1513 U : String := "Unsigned_ "; 1514 N : Natural := 9; 1515 1516 begin 1517 for J in S'Range loop 1518 N := N + 1; 1519 U (N) := S (J); 1520 end loop; 1521 1522 return U (1 .. N); 1523 end Type_Img; 1524 1525 F : Natural; 1526 L : Natural; 1527 P : Natural; 1528 1529 FName : String := Ada_File_Base_Name (Pkg_Name) & ".ads"; 1530 -- Initially, the name of the spec file, then modified to be the name of 1531 -- the body file. Not used if Use_Stdout is True. 1532 1533 -- Start of processing for Produce 1534 1535 begin 1536 1537 if Verbose and then not Use_Stdout then 1538 Put (Output, 1539 "Producing " & Ada.Directories.Current_Directory & "/" & FName); 1540 New_Line (Output); 1541 end if; 1542 1543 if not Use_Stdout then 1544 File := Create_File (FName, Binary); 1545 1546 if File = Invalid_FD then 1547 raise Program_Error with "cannot create: " & FName; 1548 end if; 1549 end if; 1550 1551 Put (File, "package "); 1552 Put (File, Pkg_Name); 1553 Put (File, " is"); 1554 New_Line (File); 1555 Put (File, " function Hash (S : String) return Natural;"); 1556 New_Line (File); 1557 Put (File, "end "); 1558 Put (File, Pkg_Name); 1559 Put (File, ";"); 1560 New_Line (File); 1561 1562 if not Use_Stdout then 1563 Close (File, Status); 1564 1565 if not Status then 1566 raise Device_Error; 1567 end if; 1568 end if; 1569 1570 if not Use_Stdout then 1571 1572 -- Set to body file name 1573 1574 FName (FName'Last) := 'b'; 1575 1576 File := Create_File (FName, Binary); 1577 1578 if File = Invalid_FD then 1579 raise Program_Error with "cannot create: " & FName; 1580 end if; 1581 end if; 1582 1583 Put (File, "with Interfaces; use Interfaces;"); 1584 New_Line (File); 1585 New_Line (File); 1586 Put (File, "package body "); 1587 Put (File, Pkg_Name); 1588 Put (File, " is"); 1589 New_Line (File); 1590 New_Line (File); 1591 1592 if Opt = CPU_Time then 1593 Put (File, Array_Img ("C", Type_Img (256), "Character")); 1594 New_Line (File); 1595 1596 F := Character'Pos (Character'First); 1597 L := Character'Pos (Character'Last); 1598 1599 for J in Character'Range loop 1600 P := Get_Used_Char (J); 1601 Put (File, Image (P), 1, 0, 1, F, L, Character'Pos (J)); 1602 end loop; 1603 1604 New_Line (File); 1605 end if; 1606 1607 F := 0; 1608 L := Char_Pos_Set_Len - 1; 1609 1610 Put (File, Array_Img ("P", "Natural", Range_Img (F, L))); 1611 New_Line (File); 1612 1613 for J in F .. L loop 1614 Put (File, Image (Get_Char_Pos (J)), 1, 0, 1, F, L, J); 1615 end loop; 1616 1617 New_Line (File); 1618 1619 case Opt is 1620 when CPU_Time => 1621 Put_Int_Matrix 1622 (File, 1623 Array_Img ("T1", Type_Img (NV), 1624 Range_Img (0, T1_Len - 1), 1625 Range_Img (0, T2_Len - 1, Type_Img (256))), 1626 T1, T1_Len, T2_Len); 1627 1628 when Memory_Space => 1629 Put_Int_Matrix 1630 (File, 1631 Array_Img ("T1", Type_Img (NV), 1632 Range_Img (0, T1_Len - 1)), 1633 T1, T1_Len, 0); 1634 end case; 1635 1636 New_Line (File); 1637 1638 case Opt is 1639 when CPU_Time => 1640 Put_Int_Matrix 1641 (File, 1642 Array_Img ("T2", Type_Img (NV), 1643 Range_Img (0, T1_Len - 1), 1644 Range_Img (0, T2_Len - 1, Type_Img (256))), 1645 T2, T1_Len, T2_Len); 1646 1647 when Memory_Space => 1648 Put_Int_Matrix 1649 (File, 1650 Array_Img ("T2", Type_Img (NV), 1651 Range_Img (0, T1_Len - 1)), 1652 T2, T1_Len, 0); 1653 end case; 1654 1655 New_Line (File); 1656 1657 Put_Int_Vector 1658 (File, 1659 Array_Img ("G", Type_Img (NK), 1660 Range_Img (0, G_Len - 1)), 1661 G, G_Len); 1662 New_Line (File); 1663 1664 Put (File, " function Hash (S : String) return Natural is"); 1665 New_Line (File); 1666 Put (File, " F : constant Natural := S'First - 1;"); 1667 New_Line (File); 1668 Put (File, " L : constant Natural := S'Length;"); 1669 New_Line (File); 1670 Put (File, " F1, F2 : Natural := 0;"); 1671 New_Line (File); 1672 1673 Put (File, " J : "); 1674 1675 case Opt is 1676 when CPU_Time => 1677 Put (File, Type_Img (256)); 1678 when Memory_Space => 1679 Put (File, "Natural"); 1680 end case; 1681 1682 Put (File, ";"); 1683 New_Line (File); 1684 1685 Put (File, " begin"); 1686 New_Line (File); 1687 Put (File, " for K in P'Range loop"); 1688 New_Line (File); 1689 Put (File, " exit when L < P (K);"); 1690 New_Line (File); 1691 Put (File, " J := "); 1692 1693 case Opt is 1694 when CPU_Time => 1695 Put (File, "C"); 1696 when Memory_Space => 1697 Put (File, "Character'Pos"); 1698 end case; 1699 1700 Put (File, " (S (P (K) + F));"); 1701 New_Line (File); 1702 1703 Put (File, " F1 := (F1 + Natural (T1 (K"); 1704 1705 if Opt = CPU_Time then 1706 Put (File, ", J"); 1707 end if; 1708 1709 Put (File, "))"); 1710 1711 if Opt = Memory_Space then 1712 Put (File, " * J"); 1713 end if; 1714 1715 Put (File, ") mod "); 1716 Put (File, Image (NV)); 1717 Put (File, ";"); 1718 New_Line (File); 1719 1720 Put (File, " F2 := (F2 + Natural (T2 (K"); 1721 1722 if Opt = CPU_Time then 1723 Put (File, ", J"); 1724 end if; 1725 1726 Put (File, "))"); 1727 1728 if Opt = Memory_Space then 1729 Put (File, " * J"); 1730 end if; 1731 1732 Put (File, ") mod "); 1733 Put (File, Image (NV)); 1734 Put (File, ";"); 1735 New_Line (File); 1736 1737 Put (File, " end loop;"); 1738 New_Line (File); 1739 1740 Put (File, 1741 " return (Natural (G (F1)) + Natural (G (F2))) mod "); 1742 1743 Put (File, Image (NK)); 1744 Put (File, ";"); 1745 New_Line (File); 1746 Put (File, " end Hash;"); 1747 New_Line (File); 1748 New_Line (File); 1749 Put (File, "end "); 1750 Put (File, Pkg_Name); 1751 Put (File, ";"); 1752 New_Line (File); 1753 1754 if not Use_Stdout then 1755 Close (File, Status); 1756 1757 if not Status then 1758 raise Device_Error; 1759 end if; 1760 end if; 1761 end Produce; 1762 1763 --------- 1764 -- Put -- 1765 --------- 1766 1767 procedure Put (File : File_Descriptor; Str : String) is 1768 Len : constant Natural := Str'Length; 1769 begin 1770 for J in Str'Range loop 1771 pragma Assert (Str (J) /= ASCII.NUL); 1772 null; 1773 end loop; 1774 1775 if Write (File, Str'Address, Len) /= Len then 1776 raise Program_Error; 1777 end if; 1778 end Put; 1779 1780 --------- 1781 -- Put -- 1782 --------- 1783 1784 procedure Put 1785 (F : File_Descriptor; 1786 S : String; 1787 F1 : Natural; 1788 L1 : Natural; 1789 C1 : Natural; 1790 F2 : Natural; 1791 L2 : Natural; 1792 C2 : Natural) 1793 is 1794 Len : constant Natural := S'Length; 1795 1796 procedure Flush; 1797 -- Write current line, followed by LF 1798 1799 ----------- 1800 -- Flush -- 1801 ----------- 1802 1803 procedure Flush is 1804 begin 1805 Put (F, Line (1 .. Last)); 1806 New_Line (F); 1807 Last := 0; 1808 end Flush; 1809 1810 -- Start of processing for Put 1811 1812 begin 1813 if C1 = F1 and then C2 = F2 then 1814 Last := 0; 1815 end if; 1816 1817 if Last + Len + 3 >= Max then 1818 Flush; 1819 end if; 1820 1821 if Last = 0 then 1822 Add (" "); 1823 1824 if F1 <= L1 then 1825 if C1 = F1 and then C2 = F2 then 1826 Add ('('); 1827 1828 if F1 = L1 then 1829 Add ("0 .. 0 => "); 1830 end if; 1831 1832 else 1833 Add (' '); 1834 end if; 1835 end if; 1836 end if; 1837 1838 if C2 = F2 then 1839 Add ('('); 1840 1841 if F2 = L2 then 1842 Add ("0 .. 0 => "); 1843 end if; 1844 1845 else 1846 Add (' '); 1847 end if; 1848 1849 Add (S); 1850 1851 if C2 = L2 then 1852 Add (')'); 1853 1854 if F1 > L1 then 1855 Add (';'); 1856 Flush; 1857 1858 elsif C1 /= L1 then 1859 Add (','); 1860 Flush; 1861 1862 else 1863 Add (')'); 1864 Add (';'); 1865 Flush; 1866 end if; 1867 1868 else 1869 Add (','); 1870 end if; 1871 end Put; 1872 1873 --------------- 1874 -- Put_Edges -- 1875 --------------- 1876 1877 procedure Put_Edges (File : File_Descriptor; Title : String) is 1878 E : Edge_Type; 1879 F1 : constant Natural := 1; 1880 L1 : constant Natural := Edges_Len - 1; 1881 M : constant Natural := Max / 5; 1882 1883 begin 1884 Put (File, Title); 1885 New_Line (File); 1886 1887 -- Edges valid range is 1 .. Edge_Len - 1 1888 1889 for J in F1 .. L1 loop 1890 E := Get_Edges (J); 1891 Put (File, Image (J, M), F1, L1, J, 1, 4, 1); 1892 Put (File, Image (E.X, M), F1, L1, J, 1, 4, 2); 1893 Put (File, Image (E.Y, M), F1, L1, J, 1, 4, 3); 1894 Put (File, Image (E.Key, M), F1, L1, J, 1, 4, 4); 1895 end loop; 1896 end Put_Edges; 1897 1898 ---------------------- 1899 -- Put_Initial_Keys -- 1900 ---------------------- 1901 1902 procedure Put_Initial_Keys (File : File_Descriptor; Title : String) is 1903 F1 : constant Natural := 0; 1904 L1 : constant Natural := NK - 1; 1905 M : constant Natural := Max / 5; 1906 K : Key_Type; 1907 1908 begin 1909 Put (File, Title); 1910 New_Line (File); 1911 1912 for J in F1 .. L1 loop 1913 K := Get_Key (J); 1914 Put (File, Image (J, M), F1, L1, J, 1, 3, 1); 1915 Put (File, Image (K.Edge, M), F1, L1, J, 1, 3, 2); 1916 Put (File, Trim_Trailing_Nuls (WT.Table (Initial (J)).all), 1917 F1, L1, J, 1, 3, 3); 1918 end loop; 1919 end Put_Initial_Keys; 1920 1921 -------------------- 1922 -- Put_Int_Matrix -- 1923 -------------------- 1924 1925 procedure Put_Int_Matrix 1926 (File : File_Descriptor; 1927 Title : String; 1928 Table : Integer; 1929 Len_1 : Natural; 1930 Len_2 : Natural) 1931 is 1932 F1 : constant Integer := 0; 1933 L1 : constant Integer := Len_1 - 1; 1934 F2 : constant Integer := 0; 1935 L2 : constant Integer := Len_2 - 1; 1936 Ix : Natural; 1937 1938 begin 1939 Put (File, Title); 1940 New_Line (File); 1941 1942 if Len_2 = 0 then 1943 for J in F1 .. L1 loop 1944 Ix := IT.Table (Table + J); 1945 Put (File, Image (Ix), 1, 0, 1, F1, L1, J); 1946 end loop; 1947 1948 else 1949 for J in F1 .. L1 loop 1950 for K in F2 .. L2 loop 1951 Ix := IT.Table (Table + J + K * Len_1); 1952 Put (File, Image (Ix), F1, L1, J, F2, L2, K); 1953 end loop; 1954 end loop; 1955 end if; 1956 end Put_Int_Matrix; 1957 1958 -------------------- 1959 -- Put_Int_Vector -- 1960 -------------------- 1961 1962 procedure Put_Int_Vector 1963 (File : File_Descriptor; 1964 Title : String; 1965 Vector : Integer; 1966 Length : Natural) 1967 is 1968 F2 : constant Natural := 0; 1969 L2 : constant Natural := Length - 1; 1970 1971 begin 1972 Put (File, Title); 1973 New_Line (File); 1974 1975 for J in F2 .. L2 loop 1976 Put (File, Image (IT.Table (Vector + J)), 1, 0, 1, F2, L2, J); 1977 end loop; 1978 end Put_Int_Vector; 1979 1980 ---------------------- 1981 -- Put_Reduced_Keys -- 1982 ---------------------- 1983 1984 procedure Put_Reduced_Keys (File : File_Descriptor; Title : String) is 1985 F1 : constant Natural := 0; 1986 L1 : constant Natural := NK - 1; 1987 M : constant Natural := Max / 5; 1988 K : Key_Type; 1989 1990 begin 1991 Put (File, Title); 1992 New_Line (File); 1993 1994 for J in F1 .. L1 loop 1995 K := Get_Key (J); 1996 Put (File, Image (J, M), F1, L1, J, 1, 3, 1); 1997 Put (File, Image (K.Edge, M), F1, L1, J, 1, 3, 2); 1998 Put (File, Trim_Trailing_Nuls (WT.Table (Reduced (J)).all), 1999 F1, L1, J, 1, 3, 3); 2000 end loop; 2001 end Put_Reduced_Keys; 2002 2003 ----------------------- 2004 -- Put_Used_Char_Set -- 2005 ----------------------- 2006 2007 procedure Put_Used_Char_Set (File : File_Descriptor; Title : String) is 2008 F : constant Natural := Character'Pos (Character'First); 2009 L : constant Natural := Character'Pos (Character'Last); 2010 2011 begin 2012 Put (File, Title); 2013 New_Line (File); 2014 2015 for J in Character'Range loop 2016 Put 2017 (File, Image (Get_Used_Char (J)), 1, 0, 1, F, L, Character'Pos (J)); 2018 end loop; 2019 end Put_Used_Char_Set; 2020 2021 ---------------------- 2022 -- Put_Vertex_Table -- 2023 ---------------------- 2024 2025 procedure Put_Vertex_Table (File : File_Descriptor; Title : String) is 2026 F1 : constant Natural := 0; 2027 L1 : constant Natural := NV - 1; 2028 M : constant Natural := Max / 4; 2029 V : Vertex_Type; 2030 2031 begin 2032 Put (File, Title); 2033 New_Line (File); 2034 2035 for J in F1 .. L1 loop 2036 V := Get_Vertices (J); 2037 Put (File, Image (J, M), F1, L1, J, 1, 3, 1); 2038 Put (File, Image (V.First, M), F1, L1, J, 1, 3, 2); 2039 Put (File, Image (V.Last, M), F1, L1, J, 1, 3, 3); 2040 end loop; 2041 end Put_Vertex_Table; 2042 2043 ------------ 2044 -- Random -- 2045 ------------ 2046 2047 procedure Random (Seed : in out Natural) is 2048 2049 -- Park & Miller Standard Minimal using Schrage's algorithm to avoid 2050 -- overflow: Xn+1 = 16807 * Xn mod (2 ** 31 - 1) 2051 2052 R : Natural; 2053 Q : Natural; 2054 X : Integer; 2055 2056 begin 2057 R := Seed mod 127773; 2058 Q := Seed / 127773; 2059 X := 16807 * R - 2836 * Q; 2060 2061 Seed := (if X < 0 then X + 2147483647 else X); 2062 end Random; 2063 2064 ------------- 2065 -- Reduced -- 2066 ------------- 2067 2068 function Reduced (K : Key_Id) return Word_Id is 2069 begin 2070 return K + NK + 1; 2071 end Reduced; 2072 2073 ----------------- 2074 -- Resize_Word -- 2075 ----------------- 2076 2077 procedure Resize_Word (W : in out Word_Type; Len : Natural) is 2078 S1 : constant String := W.all; 2079 S2 : String (1 .. Len) := (others => ASCII.NUL); 2080 L : constant Natural := S1'Length; 2081 begin 2082 if L /= Len then 2083 Free_Word (W); 2084 S2 (1 .. L) := S1; 2085 W := New_Word (S2); 2086 end if; 2087 end Resize_Word; 2088 2089 -------------------------- 2090 -- Select_Char_Position -- 2091 -------------------------- 2092 2093 procedure Select_Char_Position is 2094 2095 type Vertex_Table_Type is array (Natural range <>) of Vertex_Type; 2096 2097 procedure Build_Identical_Keys_Sets 2098 (Table : in out Vertex_Table_Type; 2099 Last : in out Natural; 2100 Pos : Natural); 2101 -- Build a list of keys subsets that are identical with the current 2102 -- position selection plus Pos. Once this routine is called, reduced 2103 -- words are sorted by subsets and each item (First, Last) in Sets 2104 -- defines the range of identical keys. 2105 -- Need comment saying exactly what Last is ??? 2106 2107 function Count_Different_Keys 2108 (Table : Vertex_Table_Type; 2109 Last : Natural; 2110 Pos : Natural) return Natural; 2111 -- For each subset in Sets, count the number of different keys if we add 2112 -- Pos to the current position selection. 2113 2114 Sel_Position : IT.Table_Type (1 .. Max_Key_Len); 2115 Last_Sel_Pos : Natural := 0; 2116 Max_Sel_Pos : Natural := 0; 2117 2118 ------------------------------- 2119 -- Build_Identical_Keys_Sets -- 2120 ------------------------------- 2121 2122 procedure Build_Identical_Keys_Sets 2123 (Table : in out Vertex_Table_Type; 2124 Last : in out Natural; 2125 Pos : Natural) 2126 is 2127 S : constant Vertex_Table_Type := Table (Table'First .. Last); 2128 C : constant Natural := Pos; 2129 -- Shortcuts (why are these not renames ???) 2130 2131 F : Integer; 2132 L : Integer; 2133 -- First and last words of a subset 2134 2135 Offset : Natural; 2136 -- GNAT.Heap_Sort assumes that the first array index is 1. Offset 2137 -- defines the translation to operate. 2138 2139 function Lt (L, R : Natural) return Boolean; 2140 procedure Move (From : Natural; To : Natural); 2141 -- Subprograms needed by GNAT.Heap_Sort_G 2142 2143 -------- 2144 -- Lt -- 2145 -------- 2146 2147 function Lt (L, R : Natural) return Boolean is 2148 C : constant Natural := Pos; 2149 Left : Natural; 2150 Right : Natural; 2151 2152 begin 2153 if L = 0 then 2154 Left := NK; 2155 Right := Offset + R; 2156 elsif R = 0 then 2157 Left := Offset + L; 2158 Right := NK; 2159 else 2160 Left := Offset + L; 2161 Right := Offset + R; 2162 end if; 2163 2164 return WT.Table (Left)(C) < WT.Table (Right)(C); 2165 end Lt; 2166 2167 ---------- 2168 -- Move -- 2169 ---------- 2170 2171 procedure Move (From : Natural; To : Natural) is 2172 Target, Source : Natural; 2173 2174 begin 2175 if From = 0 then 2176 Source := NK; 2177 Target := Offset + To; 2178 elsif To = 0 then 2179 Source := Offset + From; 2180 Target := NK; 2181 else 2182 Source := Offset + From; 2183 Target := Offset + To; 2184 end if; 2185 2186 WT.Table (Target) := WT.Table (Source); 2187 WT.Table (Source) := null; 2188 end Move; 2189 2190 package Sorting is new GNAT.Heap_Sort_G (Move, Lt); 2191 2192 -- Start of processing for Build_Identical_Key_Sets 2193 2194 begin 2195 Last := 0; 2196 2197 -- For each subset in S, extract the new subsets we have by adding C 2198 -- in the position selection. 2199 2200 for J in S'Range loop 2201 if S (J).First = S (J).Last then 2202 F := S (J).First; 2203 L := S (J).Last; 2204 Last := Last + 1; 2205 Table (Last) := (F, L); 2206 2207 else 2208 Offset := Reduced (S (J).First) - 1; 2209 Sorting.Sort (S (J).Last - S (J).First + 1); 2210 2211 F := S (J).First; 2212 L := F; 2213 for N in S (J).First .. S (J).Last loop 2214 2215 -- For the last item, close the last subset 2216 2217 if N = S (J).Last then 2218 Last := Last + 1; 2219 Table (Last) := (F, N); 2220 2221 -- Two contiguous words are identical when they have the 2222 -- same Cth character. 2223 2224 elsif WT.Table (Reduced (N))(C) = 2225 WT.Table (Reduced (N + 1))(C) 2226 then 2227 L := N + 1; 2228 2229 -- Find a new subset of identical keys. Store the current 2230 -- one and create a new subset. 2231 2232 else 2233 Last := Last + 1; 2234 Table (Last) := (F, L); 2235 F := N + 1; 2236 L := F; 2237 end if; 2238 end loop; 2239 end if; 2240 end loop; 2241 end Build_Identical_Keys_Sets; 2242 2243 -------------------------- 2244 -- Count_Different_Keys -- 2245 -------------------------- 2246 2247 function Count_Different_Keys 2248 (Table : Vertex_Table_Type; 2249 Last : Natural; 2250 Pos : Natural) return Natural 2251 is 2252 N : array (Character) of Natural; 2253 C : Character; 2254 T : Natural := 0; 2255 2256 begin 2257 -- For each subset, count the number of words that are still 2258 -- different when we include Pos in the position selection. Only 2259 -- focus on this position as the other positions already produce 2260 -- identical keys. 2261 2262 for S in 1 .. Last loop 2263 2264 -- Count the occurrences of the different characters 2265 2266 N := (others => 0); 2267 for K in Table (S).First .. Table (S).Last loop 2268 C := WT.Table (Reduced (K))(Pos); 2269 N (C) := N (C) + 1; 2270 end loop; 2271 2272 -- Update the number of different keys. Each character used 2273 -- denotes a different key. 2274 2275 for J in N'Range loop 2276 if N (J) > 0 then 2277 T := T + 1; 2278 end if; 2279 end loop; 2280 end loop; 2281 2282 return T; 2283 end Count_Different_Keys; 2284 2285 -- Start of processing for Select_Char_Position 2286 2287 begin 2288 -- Initialize the reduced words set 2289 2290 for K in 0 .. NK - 1 loop 2291 WT.Table (Reduced (K)) := New_Word (WT.Table (Initial (K)).all); 2292 end loop; 2293 2294 declare 2295 Differences : Natural; 2296 Max_Differences : Natural := 0; 2297 Old_Differences : Natural; 2298 Max_Diff_Sel_Pos : Natural := 0; -- init to kill warning 2299 Max_Diff_Sel_Pos_Idx : Natural := 0; -- init to kill warning 2300 Same_Keys_Sets_Table : Vertex_Table_Type (1 .. NK); 2301 Same_Keys_Sets_Last : Natural := 1; 2302 2303 begin 2304 for C in Sel_Position'Range loop 2305 Sel_Position (C) := C; 2306 end loop; 2307 2308 Same_Keys_Sets_Table (1) := (0, NK - 1); 2309 2310 loop 2311 -- Preserve maximum number of different keys and check later on 2312 -- that this value is strictly incrementing. Otherwise, it means 2313 -- that two keys are strictly identical. 2314 2315 Old_Differences := Max_Differences; 2316 2317 -- The first position should not exceed the minimum key length. 2318 -- Otherwise, we may end up with an empty word once reduced. 2319 2320 Max_Sel_Pos := 2321 (if Last_Sel_Pos = 0 then Min_Key_Len else Max_Key_Len); 2322 2323 -- Find which position increases more the number of differences 2324 2325 for J in Last_Sel_Pos + 1 .. Max_Sel_Pos loop 2326 Differences := Count_Different_Keys 2327 (Same_Keys_Sets_Table, 2328 Same_Keys_Sets_Last, 2329 Sel_Position (J)); 2330 2331 if Verbose then 2332 Put (Output, 2333 "Selecting position" & Sel_Position (J)'Img & 2334 " results in" & Differences'Img & 2335 " differences"); 2336 New_Line (Output); 2337 end if; 2338 2339 if Differences > Max_Differences then 2340 Max_Differences := Differences; 2341 Max_Diff_Sel_Pos := Sel_Position (J); 2342 Max_Diff_Sel_Pos_Idx := J; 2343 end if; 2344 end loop; 2345 2346 if Old_Differences = Max_Differences then 2347 raise Program_Error with "some keys are identical"; 2348 end if; 2349 2350 -- Insert selected position and sort Sel_Position table 2351 2352 Last_Sel_Pos := Last_Sel_Pos + 1; 2353 Sel_Position (Last_Sel_Pos + 1 .. Max_Diff_Sel_Pos_Idx) := 2354 Sel_Position (Last_Sel_Pos .. Max_Diff_Sel_Pos_Idx - 1); 2355 Sel_Position (Last_Sel_Pos) := Max_Diff_Sel_Pos; 2356 2357 for P in 1 .. Last_Sel_Pos - 1 loop 2358 if Max_Diff_Sel_Pos < Sel_Position (P) then 2359 Sel_Position (P + 1 .. Last_Sel_Pos) := 2360 Sel_Position (P .. Last_Sel_Pos - 1); 2361 Sel_Position (P) := Max_Diff_Sel_Pos; 2362 exit; 2363 end if; 2364 end loop; 2365 2366 exit when Max_Differences = NK; 2367 2368 Build_Identical_Keys_Sets 2369 (Same_Keys_Sets_Table, 2370 Same_Keys_Sets_Last, 2371 Max_Diff_Sel_Pos); 2372 2373 if Verbose then 2374 Put (Output, 2375 "Selecting position" & Max_Diff_Sel_Pos'Img & 2376 " results in" & Max_Differences'Img & 2377 " differences"); 2378 New_Line (Output); 2379 Put (Output, "--"); 2380 New_Line (Output); 2381 for J in 1 .. Same_Keys_Sets_Last loop 2382 for K in 2383 Same_Keys_Sets_Table (J).First .. 2384 Same_Keys_Sets_Table (J).Last 2385 loop 2386 Put (Output, 2387 Trim_Trailing_Nuls (WT.Table (Reduced (K)).all)); 2388 New_Line (Output); 2389 end loop; 2390 Put (Output, "--"); 2391 New_Line (Output); 2392 end loop; 2393 end if; 2394 end loop; 2395 end; 2396 2397 Char_Pos_Set_Len := Last_Sel_Pos; 2398 Char_Pos_Set := Allocate (Char_Pos_Set_Len); 2399 2400 for C in 1 .. Last_Sel_Pos loop 2401 Set_Char_Pos (C - 1, Sel_Position (C)); 2402 end loop; 2403 end Select_Char_Position; 2404 2405 -------------------------- 2406 -- Select_Character_Set -- 2407 -------------------------- 2408 2409 procedure Select_Character_Set is 2410 Last : Natural := 0; 2411 Used : array (Character) of Boolean := (others => False); 2412 Char : Character; 2413 2414 begin 2415 for J in 0 .. NK - 1 loop 2416 for K in 0 .. Char_Pos_Set_Len - 1 loop 2417 Char := WT.Table (Initial (J))(Get_Char_Pos (K)); 2418 exit when Char = ASCII.NUL; 2419 Used (Char) := True; 2420 end loop; 2421 end loop; 2422 2423 Used_Char_Set_Len := 256; 2424 Used_Char_Set := Allocate (Used_Char_Set_Len); 2425 2426 for J in Used'Range loop 2427 if Used (J) then 2428 Set_Used_Char (J, Last); 2429 Last := Last + 1; 2430 else 2431 Set_Used_Char (J, 0); 2432 end if; 2433 end loop; 2434 end Select_Character_Set; 2435 2436 ------------------ 2437 -- Set_Char_Pos -- 2438 ------------------ 2439 2440 procedure Set_Char_Pos (P : Natural; Item : Natural) is 2441 N : constant Natural := Char_Pos_Set + P; 2442 begin 2443 IT.Table (N) := Item; 2444 end Set_Char_Pos; 2445 2446 --------------- 2447 -- Set_Edges -- 2448 --------------- 2449 2450 procedure Set_Edges (F : Natural; Item : Edge_Type) is 2451 N : constant Natural := Edges + (F * Edge_Size); 2452 begin 2453 IT.Table (N) := Item.X; 2454 IT.Table (N + 1) := Item.Y; 2455 IT.Table (N + 2) := Item.Key; 2456 end Set_Edges; 2457 2458 --------------- 2459 -- Set_Graph -- 2460 --------------- 2461 2462 procedure Set_Graph (N : Natural; Item : Integer) is 2463 begin 2464 IT.Table (G + N) := Item; 2465 end Set_Graph; 2466 2467 ------------- 2468 -- Set_Key -- 2469 ------------- 2470 2471 procedure Set_Key (N : Key_Id; Item : Key_Type) is 2472 begin 2473 IT.Table (Keys + N) := Item.Edge; 2474 end Set_Key; 2475 2476 --------------- 2477 -- Set_Table -- 2478 --------------- 2479 2480 procedure Set_Table (T : Integer; X, Y : Natural; Item : Natural) is 2481 N : constant Natural := T + ((Y * T1_Len) + X); 2482 begin 2483 IT.Table (N) := Item; 2484 end Set_Table; 2485 2486 ------------------- 2487 -- Set_Used_Char -- 2488 ------------------- 2489 2490 procedure Set_Used_Char (C : Character; Item : Natural) is 2491 N : constant Natural := Used_Char_Set + Character'Pos (C); 2492 begin 2493 IT.Table (N) := Item; 2494 end Set_Used_Char; 2495 2496 ------------------ 2497 -- Set_Vertices -- 2498 ------------------ 2499 2500 procedure Set_Vertices (F : Natural; Item : Vertex_Type) is 2501 N : constant Natural := Vertices + (F * Vertex_Size); 2502 begin 2503 IT.Table (N) := Item.First; 2504 IT.Table (N + 1) := Item.Last; 2505 end Set_Vertices; 2506 2507 --------- 2508 -- Sum -- 2509 --------- 2510 2511 function Sum 2512 (Word : Word_Type; 2513 Table : Table_Id; 2514 Opt : Optimization) return Natural 2515 is 2516 S : Natural := 0; 2517 R : Natural; 2518 2519 begin 2520 case Opt is 2521 when CPU_Time => 2522 for J in 0 .. T1_Len - 1 loop 2523 exit when Word (J + 1) = ASCII.NUL; 2524 R := Get_Table (Table, J, Get_Used_Char (Word (J + 1))); 2525 S := (S + R) mod NV; 2526 end loop; 2527 2528 when Memory_Space => 2529 for J in 0 .. T1_Len - 1 loop 2530 exit when Word (J + 1) = ASCII.NUL; 2531 R := Get_Table (Table, J, 0); 2532 S := (S + R * Character'Pos (Word (J + 1))) mod NV; 2533 end loop; 2534 end case; 2535 2536 return S; 2537 end Sum; 2538 2539 ------------------------ 2540 -- Trim_Trailing_Nuls -- 2541 ------------------------ 2542 2543 function Trim_Trailing_Nuls (Str : String) return String is 2544 begin 2545 for J in reverse Str'Range loop 2546 if Str (J) /= ASCII.NUL then 2547 return Str (Str'First .. J); 2548 end if; 2549 end loop; 2550 2551 return Str; 2552 end Trim_Trailing_Nuls; 2553 2554 --------------- 2555 -- Type_Size -- 2556 --------------- 2557 2558 function Type_Size (L : Natural) return Natural is 2559 begin 2560 if L <= 2 ** 8 then 2561 return 8; 2562 elsif L <= 2 ** 16 then 2563 return 16; 2564 else 2565 return 32; 2566 end if; 2567 end Type_Size; 2568 2569 ----------- 2570 -- Value -- 2571 ----------- 2572 2573 function Value 2574 (Name : Table_Name; 2575 J : Natural; 2576 K : Natural := 0) return Natural 2577 is 2578 begin 2579 case Name is 2580 when Character_Position => 2581 return Get_Char_Pos (J); 2582 2583 when Used_Character_Set => 2584 return Get_Used_Char (Character'Val (J)); 2585 2586 when Function_Table_1 => 2587 return Get_Table (T1, J, K); 2588 2589 when Function_Table_2 => 2590 return Get_Table (T2, J, K); 2591 2592 when Graph_Table => 2593 return Get_Graph (J); 2594 2595 end case; 2596 end Value; 2597 2598end GNAT.Perfect_Hash_Generators; 2599