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Diffstat (limited to 'gcc-4.4.3/gcc/ada/a-nudira.adb')
| -rw-r--r-- | gcc-4.4.3/gcc/ada/a-nudira.adb | 274 |
1 files changed, 0 insertions, 274 deletions
diff --git a/gcc-4.4.3/gcc/ada/a-nudira.adb b/gcc-4.4.3/gcc/ada/a-nudira.adb deleted file mode 100644 index 087ce56ea..000000000 --- a/gcc-4.4.3/gcc/ada/a-nudira.adb +++ /dev/null @@ -1,274 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT RUN-TIME COMPONENTS -- --- -- --- A D A . N U M E R I C S . D I S C R E T E _ R A N D O M -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- --- -- --- 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 3, 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. -- --- -- --- As a special exception under Section 7 of GPL version 3, you are granted -- --- additional permissions described in the GCC Runtime Library Exception, -- --- version 3.1, as published by the Free Software Foundation. -- --- -- --- You should have received a copy of the GNU General Public License and -- --- a copy of the GCC Runtime Library Exception along with this program; -- --- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- --- <http://www.gnu.org/licenses/>. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -with Ada.Calendar; - -with Interfaces; use Interfaces; - -package body Ada.Numerics.Discrete_Random is - - ------------------------- - -- Implementation Note -- - ------------------------- - - -- The design of this spec is very awkward, as a result of Ada 95 not - -- permitting in-out parameters for function formals (most naturally - -- Generator values would be passed this way). In pure Ada 95, the only - -- solution is to use the heap and pointers, and, to avoid memory leaks, - -- controlled types. - - -- This is awfully heavy, so what we do is to use Unrestricted_Access to - -- get a pointer to the state in the passed Generator. This works because - -- Generator is a limited type and will thus always be passed by reference. - - type Pointer is access all State; - - Need_64 : constant Boolean := Rst'Pos (Rst'Last) > Int'Last; - -- Set if we need more than 32 bits in the result. In practice we will - -- only use the meaningful 48 bits of any 64 bit number generated, since - -- if more than 48 bits are required, we split the computation into two - -- separate parts, since the algorithm does not behave above 48 bits. - - ----------------------- - -- Local Subprograms -- - ----------------------- - - function Square_Mod_N (X, N : Int) return Int; - pragma Inline (Square_Mod_N); - -- Computes X**2 mod N avoiding intermediate overflow - - ----------- - -- Image -- - ----------- - - function Image (Of_State : State) return String is - begin - return Int'Image (Of_State.X1) & - ',' & - Int'Image (Of_State.X2) & - ',' & - Int'Image (Of_State.Q); - end Image; - - ------------ - -- Random -- - ------------ - - function Random (Gen : Generator) return Rst is - Genp : constant Pointer := Gen.Gen_State'Unrestricted_Access; - Temp : Int; - TF : Flt; - - begin - -- Check for flat range here, since we are typically run with checks - -- off, note that in practice, this condition will usually be static - -- so we will not actually generate any code for the normal case. - - if Rst'Last < Rst'First then - raise Constraint_Error; - end if; - - -- Continue with computation if non-flat range - - Genp.X1 := Square_Mod_N (Genp.X1, Genp.P); - Genp.X2 := Square_Mod_N (Genp.X2, Genp.Q); - Temp := Genp.X2 - Genp.X1; - - -- Following duplication is not an error, it is a loop unwinding! - - if Temp < 0 then - Temp := Temp + Genp.Q; - end if; - - if Temp < 0 then - Temp := Temp + Genp.Q; - end if; - - TF := Offs + (Flt (Temp) * Flt (Genp.P) + Flt (Genp.X1)) * Genp.Scl; - - -- Pathological, but there do exist cases where the rounding implicit - -- in calculating the scale factor will cause rounding to 'Last + 1. - -- In those cases, returning 'First results in the least bias. - - if TF >= Flt (Rst'Pos (Rst'Last)) + 0.5 then - return Rst'First; - - elsif Need_64 then - return Rst'Val (Interfaces.Integer_64 (TF)); - - else - return Rst'Val (Int (TF)); - end if; - end Random; - - ----------- - -- Reset -- - ----------- - - procedure Reset (Gen : Generator; Initiator : Integer) is - Genp : constant Pointer := Gen.Gen_State'Unrestricted_Access; - X1, X2 : Int; - - begin - X1 := 2 + Int (Initiator) mod (K1 - 3); - X2 := 2 + Int (Initiator) mod (K2 - 3); - - for J in 1 .. 5 loop - X1 := Square_Mod_N (X1, K1); - X2 := Square_Mod_N (X2, K2); - end loop; - - -- Eliminate effects of small Initiators - - Genp.all := - (X1 => X1, - X2 => X2, - P => K1, - Q => K2, - FP => K1F, - Scl => Scal); - end Reset; - - ----------- - -- Reset -- - ----------- - - procedure Reset (Gen : Generator) is - Genp : constant Pointer := Gen.Gen_State'Unrestricted_Access; - Now : constant Calendar.Time := Calendar.Clock; - X1 : Int; - X2 : Int; - - begin - X1 := Int (Calendar.Year (Now)) * 12 * 31 + - Int (Calendar.Month (Now) * 31) + - Int (Calendar.Day (Now)); - - X2 := Int (Calendar.Seconds (Now) * Duration (1000.0)); - - X1 := 2 + X1 mod (K1 - 3); - X2 := 2 + X2 mod (K2 - 3); - - -- Eliminate visible effects of same day starts - - for J in 1 .. 5 loop - X1 := Square_Mod_N (X1, K1); - X2 := Square_Mod_N (X2, K2); - end loop; - - Genp.all := - (X1 => X1, - X2 => X2, - P => K1, - Q => K2, - FP => K1F, - Scl => Scal); - - end Reset; - - ----------- - -- Reset -- - ----------- - - procedure Reset (Gen : Generator; From_State : State) is - Genp : constant Pointer := Gen.Gen_State'Unrestricted_Access; - begin - Genp.all := From_State; - end Reset; - - ---------- - -- Save -- - ---------- - - procedure Save (Gen : Generator; To_State : out State) is - begin - To_State := Gen.Gen_State; - end Save; - - ------------------ - -- Square_Mod_N -- - ------------------ - - function Square_Mod_N (X, N : Int) return Int is - begin - return Int ((Integer_64 (X) ** 2) mod (Integer_64 (N))); - end Square_Mod_N; - - ----------- - -- Value -- - ----------- - - function Value (Coded_State : String) return State is - Last : constant Natural := Coded_State'Last; - Start : Positive := Coded_State'First; - Stop : Positive := Coded_State'First; - Outs : State; - - begin - while Stop <= Last and then Coded_State (Stop) /= ',' loop - Stop := Stop + 1; - end loop; - - if Stop > Last then - raise Constraint_Error; - end if; - - Outs.X1 := Int'Value (Coded_State (Start .. Stop - 1)); - Start := Stop + 1; - - loop - Stop := Stop + 1; - exit when Stop > Last or else Coded_State (Stop) = ','; - end loop; - - if Stop > Last then - raise Constraint_Error; - end if; - - Outs.X2 := Int'Value (Coded_State (Start .. Stop - 1)); - Outs.Q := Int'Value (Coded_State (Stop + 1 .. Last)); - Outs.P := Outs.Q * 2 + 1; - Outs.FP := Flt (Outs.P); - Outs.Scl := (RstL - RstF + 1.0) / (Flt (Outs.P) * Flt (Outs.Q)); - - -- Now do *some* sanity checks - - if Outs.Q < 31 - or else Outs.X1 not in 2 .. Outs.P - 1 - or else Outs.X2 not in 2 .. Outs.Q - 1 - then - raise Constraint_Error; - end if; - - return Outs; - end Value; - -end Ada.Numerics.Discrete_Random; |