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Diffstat (limited to 'gcc/ada/a-crbtgk.adb')
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1 files changed, 523 insertions, 0 deletions
diff --git a/gcc/ada/a-crbtgk.adb b/gcc/ada/a-crbtgk.adb new file mode 100644 index 00000000000..70c8f35278c --- /dev/null +++ b/gcc/ada/a-crbtgk.adb @@ -0,0 +1,523 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT LIBRARY COMPONENTS -- +-- -- +-- ADA.CONTAINERS.RED_BLACK_TREES.GENERIC_KEYS -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 2004 Free Software Foundation, Inc. -- +-- -- +-- This specification is derived from the Ada Reference Manual for use with -- +-- GNAT. The copyright notice above, and the license provisions that follow -- +-- apply solely to the contents of the part following the private keyword. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- +-- MA 02111-1307, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- This unit was originally developed by Matthew J Heaney. -- +------------------------------------------------------------------------------ + +package body Ada.Containers.Red_Black_Trees.Generic_Keys is + + package Ops renames Tree_Operations; + + ------------- + -- Ceiling -- + ------------- + + -- AKA Lower_Bound + + function Ceiling (Tree : Tree_Type; Key : Key_Type) return Node_Access is + Y : Node_Access; + X : Node_Access := Tree.Root; + + begin + while X /= Ops.Null_Node loop + if Is_Greater_Key_Node (Key, X) then + X := Ops.Right (X); + else + Y := X; + X := Ops.Left (X); + end if; + end loop; + + return Y; + end Ceiling; + + ---------- + -- Find -- + ---------- + + function Find (Tree : Tree_Type; Key : Key_Type) return Node_Access is + Y : Node_Access; + X : Node_Access := Tree.Root; + + begin + while X /= Ops.Null_Node loop + if Is_Greater_Key_Node (Key, X) then + X := Ops.Right (X); + else + Y := X; + X := Ops.Left (X); + end if; + end loop; + + if Y = Ops.Null_Node then + return Ops.Null_Node; + end if; + + if Is_Less_Key_Node (Key, Y) then + return Ops.Null_Node; + end if; + + return Y; + end Find; + + ----------- + -- Floor -- + ----------- + + function Floor (Tree : Tree_Type; Key : Key_Type) return Node_Access is + Y : Node_Access; + X : Node_Access := Tree.Root; + + begin + while X /= Ops.Null_Node loop + if Is_Less_Key_Node (Key, X) then + X := Ops.Left (X); + else + Y := X; + X := Ops.Right (X); + end if; + end loop; + + return Y; + end Floor; + + -------------------------------- + -- Generic_Conditional_Insert -- + -------------------------------- + + procedure Generic_Conditional_Insert + (Tree : in out Tree_Type; + Key : Key_Type; + Node : out Node_Access; + Success : out Boolean) + is + Y : Node_Access := Ops.Null_Node; + X : Node_Access := Tree.Root; + + begin + Success := True; + while X /= Ops.Null_Node loop + Y := X; + Success := Is_Less_Key_Node (Key, X); + + if Success then + X := Ops.Left (X); + else + X := Ops.Right (X); + end if; + end loop; + + Node := Y; + + if Success then + if Node = Tree.First then + Insert_Post (Tree, X, Y, Key, Node); + return; + end if; + + Node := Ops.Previous (Node); + end if; + + if Is_Greater_Key_Node (Key, Node) then + Insert_Post (Tree, X, Y, Key, Node); + Success := True; + return; + end if; + + Success := False; + end Generic_Conditional_Insert; + + ------------------------------------------ + -- Generic_Conditional_Insert_With_Hint -- + ------------------------------------------ + + procedure Generic_Conditional_Insert_With_Hint + (Tree : in out Tree_Type; + Position : Node_Access; + Key : Key_Type; + Node : out Node_Access; + Success : out Boolean) + is + begin + if Position = Ops.Null_Node then -- largest + if Tree.Length > 0 + and then Is_Greater_Key_Node (Key, Tree.Last) + then + Insert_Post (Tree, Ops.Null_Node, Tree.Last, Key, Node); + Success := True; + else + Conditional_Insert_Sans_Hint (Tree, Key, Node, Success); + end if; + + return; + end if; + + pragma Assert (Tree.Length > 0); + + if Is_Less_Key_Node (Key, Position) then + if Position = Tree.First then + Insert_Post (Tree, Position, Position, Key, Node); + Success := True; + return; + end if; + + declare + Before : constant Node_Access := Ops.Previous (Position); + + begin + if Is_Greater_Key_Node (Key, Before) then + if Ops.Right (Before) = Ops.Null_Node then + Insert_Post (Tree, Ops.Null_Node, Before, Key, Node); + else + Insert_Post (Tree, Position, Position, Key, Node); + end if; + + Success := True; + + else + Conditional_Insert_Sans_Hint (Tree, Key, Node, Success); + end if; + end; + + return; + end if; + + if Is_Greater_Key_Node (Key, Position) then + if Position = Tree.Last then + Insert_Post (Tree, Ops.Null_Node, Tree.Last, Key, Node); + Success := True; + return; + end if; + + declare + After : constant Node_Access := Ops.Next (Position); + + begin + if Is_Less_Key_Node (Key, After) then + if Ops.Right (Position) = Ops.Null_Node then + Insert_Post (Tree, Ops.Null_Node, Position, Key, Node); + else + Insert_Post (Tree, After, After, Key, Node); + end if; + + Success := True; + + else + Conditional_Insert_Sans_Hint (Tree, Key, Node, Success); + end if; + end; + + return; + end if; + + Node := Position; + Success := False; + end Generic_Conditional_Insert_With_Hint; + + ------------------------- + -- Generic_Insert_Post -- + ------------------------- + + procedure Generic_Insert_Post + (Tree : in out Tree_Type; + X, Y : Node_Access; + Key : Key_Type; + Z : out Node_Access) + is + subtype Length_Subtype is Count_Type range 0 .. Count_Type'Last - 1; + + New_Length : constant Count_Type := Length_Subtype'(Tree.Length) + 1; + + begin + if Y = Ops.Null_Node + or else X /= Ops.Null_Node + or else Is_Less_Key_Node (Key, Y) + then + pragma Assert (Y = Ops.Null_Node + or else Ops.Left (Y) = Ops.Null_Node); + + -- Delay allocation as long as we can, in order to defend + -- against exceptions propagated by relational operators. + + Z := New_Node; + + pragma Assert (Z /= Ops.Null_Node); + pragma Assert (Ops.Color (Z) = Red); + + if Y = Ops.Null_Node then + pragma Assert (Tree.Length = 0); + pragma Assert (Tree.Root = Ops.Null_Node); + pragma Assert (Tree.First = Ops.Null_Node); + pragma Assert (Tree.Last = Ops.Null_Node); + + Tree.Root := Z; + Tree.First := Z; + Tree.Last := Z; + + else + Ops.Set_Left (Y, Z); + + if Y = Tree.First then + Tree.First := Z; + end if; + end if; + + else + pragma Assert (Ops.Right (Y) = Ops.Null_Node); + + -- Delay allocation as long as we can, in order to defend + -- against exceptions propagated by relational operators. + + Z := New_Node; + + pragma Assert (Z /= Ops.Null_Node); + pragma Assert (Ops.Color (Z) = Red); + + Ops.Set_Right (Y, Z); + + if Y = Tree.Last then + Tree.Last := Z; + end if; + end if; + + Ops.Set_Parent (Z, Y); + Ops.Rebalance_For_Insert (Tree, Z); + Tree.Length := New_Length; + end Generic_Insert_Post; + + ----------------------- + -- Generic_Iteration -- + ----------------------- + + procedure Generic_Iteration + (Tree : Tree_Type; + Key : Key_Type) + is + procedure Iterate (Node : Node_Access); + + ------------- + -- Iterate -- + ------------- + + procedure Iterate (Node : Node_Access) is + N : Node_Access := Node; + begin + while N /= Ops.Null_Node loop + if Is_Less_Key_Node (Key, N) then + N := Ops.Left (N); + elsif Is_Greater_Key_Node (Key, N) then + N := Ops.Right (N); + else + Iterate (Ops.Left (N)); + Process (N); + N := Ops.Right (N); + end if; + end loop; + end Iterate; + + -- Start of processing for Generic_Iteration + + begin + Iterate (Tree.Root); + end Generic_Iteration; + + ------------------------------- + -- Generic_Reverse_Iteration -- + ------------------------------- + + procedure Generic_Reverse_Iteration + (Tree : Tree_Type; + Key : Key_Type) + is + procedure Iterate (Node : Node_Access); + + ------------- + -- Iterate -- + ------------- + + procedure Iterate (Node : Node_Access) is + N : Node_Access := Node; + begin + while N /= Ops.Null_Node loop + if Is_Less_Key_Node (Key, N) then + N := Ops.Left (N); + elsif Is_Greater_Key_Node (Key, N) then + N := Ops.Right (N); + else + Iterate (Ops.Right (N)); + Process (N); + N := Ops.Left (N); + end if; + end loop; + end Iterate; + + -- Start of processing for Generic_Reverse_Iteration + + begin + Iterate (Tree.Root); + end Generic_Reverse_Iteration; + + ---------------------------------- + -- Generic_Unconditional_Insert -- + ---------------------------------- + + procedure Generic_Unconditional_Insert + (Tree : in out Tree_Type; + Key : Key_Type; + Node : out Node_Access) + is + Y : Node_Access := Ops.Null_Node; + X : Node_Access := Tree.Root; + + begin + while X /= Ops.Null_Node loop + Y := X; + + if Is_Less_Key_Node (Key, X) then + X := Ops.Left (X); + else + X := Ops.Right (X); + end if; + end loop; + + Insert_Post (Tree, X, Y, Key, Node); + end Generic_Unconditional_Insert; + + -------------------------------------------- + -- Generic_Unconditional_Insert_With_Hint -- + -------------------------------------------- + + procedure Generic_Unconditional_Insert_With_Hint + (Tree : in out Tree_Type; + Hint : Node_Access; + Key : Key_Type; + Node : out Node_Access) + is + -- TODO: verify this algorithm. It was (quickly) adapted it from the + -- same algorithm for conditional_with_hint. It may be that the test + -- Key > Hint should be something like a Key >= Hint, to handle the + -- case when Hint is The Last Item of A (Contiguous) sequence of + -- Equivalent Items. (The Key < Hint Test is probably OK. It is not + -- clear that you can use Key <= Hint, since new items are always + -- inserted last in the sequence of equivalent items.) ??? + + begin + if Hint = Ops.Null_Node then -- largest + if Tree.Length > 0 + and then Is_Greater_Key_Node (Key, Tree.Last) + then + Insert_Post (Tree, Ops.Null_Node, Tree.Last, Key, Node); + else + Unconditional_Insert_Sans_Hint (Tree, Key, Node); + end if; + + return; + end if; + + pragma Assert (Tree.Length > 0); + + if Is_Less_Key_Node (Key, Hint) then + if Hint = Tree.First then + Insert_Post (Tree, Hint, Hint, Key, Node); + return; + end if; + + declare + Before : constant Node_Access := Ops.Previous (Hint); + begin + if Is_Greater_Key_Node (Key, Before) then + if Ops.Right (Before) = Ops.Null_Node then + Insert_Post (Tree, Ops.Null_Node, Before, Key, Node); + else + Insert_Post (Tree, Hint, Hint, Key, Node); + end if; + else + Unconditional_Insert_Sans_Hint (Tree, Key, Node); + end if; + end; + + return; + end if; + + if Is_Greater_Key_Node (Key, Hint) then + if Hint = Tree.Last then + Insert_Post (Tree, Ops.Null_Node, Tree.Last, Key, Node); + return; + end if; + + declare + After : constant Node_Access := Ops.Next (Hint); + begin + if Is_Less_Key_Node (Key, After) then + if Ops.Right (Hint) = Ops.Null_Node then + Insert_Post (Tree, Ops.Null_Node, Hint, Key, Node); + else + Insert_Post (Tree, After, After, Key, Node); + end if; + else + Unconditional_Insert_Sans_Hint (Tree, Key, Node); + end if; + end; + + return; + end if; + + Unconditional_Insert_Sans_Hint (Tree, Key, Node); + end Generic_Unconditional_Insert_With_Hint; + + ----------------- + -- Upper_Bound -- + ----------------- + + function Upper_Bound + (Tree : Tree_Type; + Key : Key_Type) return Node_Access + is + Y : Node_Access; + X : Node_Access := Tree.Root; + + begin + while X /= Ops.Null_Node loop + if Is_Less_Key_Node (Key, X) then + Y := X; + X := Ops.Left (X); + else + X := Ops.Right (X); + end if; + end loop; + + return Y; + end Upper_Bound; + +end Ada.Containers.Red_Black_Trees.Generic_Keys; + + |