CbC/CbC_gcc: gcc/ada/libgnarl/a-reatim.adb comparison

comparison gcc/ada/libgnarl/a-reatim.adb @ 111:04ced10e8804

gcc 7

author	kono
date	Fri, 27 Oct 2017 22:46:09 +0900
parents
children	84e7813d76e9

comparison

equal deleted inserted replaced

-:561a7518be6b
+:04ced10e8804
+------------------------------------------------------------------------------
+--                                                                          --
+--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
+--                                                                          --
+--                         A D A . R E A L _ T I M E                        --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--             Copyright (C) 1991-2017, Florida State University            --
+--                     Copyright (C) 1995-2017, AdaCore                     --
+--                                                                          --
+-- 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/>.                                          --
+--                                                                          --
+-- GNARL was developed by the GNARL team at Florida State University.       --
+-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
+--                                                                          --
+------------------------------------------------------------------------------
+with System.Tasking;
+with Unchecked_Conversion;
+package body Ada.Real_Time with
+SPARK_Mode => Off
+is
+---------
+-- "*" --
+---------
+--  Note that Constraint_Error may be propagated
+function "*" (Left : Time_Span; Right : Integer) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span (Duration (Left) * Right);
+end "*";
+function "*" (Left : Integer; Right : Time_Span) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span (Left * Duration (Right));
+end "*";
+---------
+-- "+" --
+---------
+--  Note that Constraint_Error may be propagated
+function "+" (Left : Time; Right : Time_Span) return Time is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time (Duration (Left) + Duration (Right));
+end "+";
+function "+" (Left : Time_Span; Right : Time) return Time is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time (Duration (Left) + Duration (Right));
+end "+";
+function "+" (Left, Right : Time_Span) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span (Duration (Left) + Duration (Right));
+end "+";
+---------
+-- "-" --
+---------
+--  Note that Constraint_Error may be propagated
+function "-" (Left : Time; Right : Time_Span) return Time is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time (Duration (Left) - Duration (Right));
+end "-";
+function "-" (Left, Right : Time) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span (Duration (Left) - Duration (Right));
+end "-";
+function "-" (Left, Right : Time_Span) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span (Duration (Left) - Duration (Right));
+end "-";
+function "-" (Right : Time_Span) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+begin
+return Time_Span_Zero - Right;
+end "-";
+---------
+-- "/" --
+---------
+--  Note that Constraint_Error may be propagated
+function "/" (Left, Right : Time_Span) return Integer is
+pragma Unsuppress (Overflow_Check);
+pragma Unsuppress (Division_Check);
+--  RM D.8 (27) specifies the effects of operators on Time_Span, and
+--  rounding of the division operator in particular, to be the same as
+--  effects on integer types. To get the correct rounding we first
+--  convert Time_Span to its root type Duration, which is represented as
+--  a 64-bit signed integer, and then use integer division.
+type Duration_Rep is range -(2 ** 63) .. +((2 ** 63 - 1));
+function To_Integer is
+new Unchecked_Conversion (Duration, Duration_Rep);
+begin
+return Integer
+(To_Integer (Duration (Left)) / To_Integer (Duration (Right)));
+end "/";
+function "/" (Left : Time_Span; Right : Integer) return Time_Span is
+pragma Unsuppress (Overflow_Check);
+pragma Unsuppress (Division_Check);
+begin
+--  Even though checks are unsuppressed, we need an explicit check for
+--  the case of largest negative integer divided by minus one, since
+--  some library routines we use fail to catch this case. This will be
+--  fixed at the compiler level in the future, at which point this test
+--  can be removed.
+if Left = Time_Span_First and then Right = -1 then
+raise Constraint_Error with "overflow";
+end if;
+return Time_Span (Duration (Left) / Right);
+end "/";
+-----------
+-- Clock --
+-----------
+function Clock return Time is
+begin
+return Time (System.Task_Primitives.Operations.Monotonic_Clock);
+end Clock;
+------------------
+-- Microseconds --
+------------------
+function Microseconds (US : Integer) return Time_Span is
+begin
+return Time_Span_Unit * US * 1_000;
+end Microseconds;
+------------------
+-- Milliseconds --
+------------------
+function Milliseconds (MS : Integer) return Time_Span is
+begin
+return Time_Span_Unit * MS * 1_000_000;
+end Milliseconds;
+-------------
+-- Minutes --
+-------------
+function Minutes (M : Integer) return Time_Span is
+begin
+return Milliseconds (M) * Integer'(60_000);
+end Minutes;
+-----------------
+-- Nanoseconds --
+-----------------
+function Nanoseconds (NS : Integer) return Time_Span is
+begin
+return Time_Span_Unit * NS;
+end Nanoseconds;
+-------------
+-- Seconds --
+-------------
+function Seconds (S : Integer) return Time_Span is
+begin
+return Milliseconds (S) * Integer'(1000);
+end Seconds;
+-----------
+-- Split --
+-----------
+procedure Split (T : Time; SC : out Seconds_Count; TS : out Time_Span) is
+T_Val : Time;
+begin
+--  Special-case for Time_First, whose absolute value is anomalous,
+--  courtesy of two's complement.
+T_Val := (if T = Time_First then abs (Time_Last) else abs (T));
+--  Extract the integer part of T, truncating towards zero
+SC :=
+(if T_Val < 0.5 then 0 else Seconds_Count (Time_Span'(T_Val - 0.5)));
+if T < 0.0 then
+SC := -SC;
+end if;
+--  If original time is negative, need to truncate towards negative
+--  infinity, to make TS non-negative, as per ARM.
+if Time (SC) > T then
+SC := SC - 1;
+end if;
+TS := Time_Span (Duration (T) - Duration (SC));
+end Split;
+-------------
+-- Time_Of --
+-------------
+function Time_Of (SC : Seconds_Count; TS : Time_Span) return Time is
+pragma Suppress (Overflow_Check);
+pragma Suppress (Range_Check);
+--  We do all our own checks for this function
+--  This is not such a simple case, since TS is already 64 bits, and
+--  so we can't just promote everything to a wider type to ensure proper
+--  testing for overflow. The situation is that Seconds_Count is a MUCH
+--  wider type than Time_Span and Time (both of which have the underlying
+--  type Duration).
+--         <------------------- Seconds_Count -------------------->
+--                            <-- Duration -->
+--  Now it is possible for an SC value outside the Duration range to
+--  be "brought back into range" by an appropriate TS value, but there
+--  are also clearly SC values that are completely out of range. Note
+--  that the above diagram is wildly out of scale, the difference in
+--  ranges is much greater than shown.
+--  We can't just go generating out of range Duration values to test for
+--  overflow, since Duration is a full range type, so we follow the steps
+--  shown below.
+SC_Lo : constant Seconds_Count :=
+Seconds_Count (Duration (Time_Span_First) + Duration'(0.5));
+SC_Hi : constant Seconds_Count :=
+Seconds_Count (Duration (Time_Span_Last)  - Duration'(0.5));
+--  These are the maximum values of the seconds (integer) part of the
+--  Duration range. Used to compute and check the seconds in the result.
+TS_SC : Seconds_Count;
+--  Seconds part of input value
+TS_Fraction : Duration;
+--  Fractional part of input value, may be negative
+Result_SC : Seconds_Count;
+--  Seconds value for result
+Fudge : constant Seconds_Count := 10;
+--  Fudge value used to do end point checks far from end point
+FudgeD : constant Duration := Duration (Fudge);
+--  Fudge value as Duration
+Fudged_Result : Duration;
+--  Result fudged up or down by FudgeD
+procedure Out_Of_Range;
+pragma No_Return (Out_Of_Range);
+--  Raise exception for result out of range
+------------------
+-- Out_Of_Range --
+------------------
+procedure Out_Of_Range is
+begin
+raise Constraint_Error with
+"result for Ada.Real_Time.Time_Of is out of range";
+end Out_Of_Range;
+--  Start of processing for Time_Of
+begin
+--  If SC is so far out of range that there is no possibility of the
+--  addition of TS getting it back in range, raise an exception right
+--  away. That way we don't have to worry about SC values overflowing.
+if SC < 3 * SC_Lo or else SC > 3 * SC_Hi then
+Out_Of_Range;
+end if;
+--  Decompose input TS value
+TS_SC := Seconds_Count (Duration (TS));
+TS_Fraction := Duration (TS) - Duration (TS_SC);
+--  Compute result seconds. If clearly out of range, raise error now
+Result_SC := SC + TS_SC;
+if Result_SC < (SC_Lo - 1) or else Result_SC > (SC_Hi + 1) then
+Out_Of_Range;
+end if;
+--  Now the result is simply Result_SC + TS_Fraction, but we can't just
+--  go computing that since it might be out of range. So what we do is
+--  to compute a value fudged down or up by 10.0 (arbitrary value, but
+--  that will do fine), and check that fudged value, and if in range
+--  unfudge it and return the result.
+--  Fudge positive result down, and check high bound
+if Result_SC > 0 then
+Fudged_Result := Duration (Result_SC - Fudge) + TS_Fraction;
+if Fudged_Result <= Duration'Last - FudgeD then
+return Time (Fudged_Result + FudgeD);
+else
+Out_Of_Range;
+end if;
+--  Same for negative values of seconds, fudge up and check low bound
+else
+Fudged_Result := Duration (Result_SC + Fudge) + TS_Fraction;
+if Fudged_Result >= Duration'First + FudgeD then
+return Time (Fudged_Result - FudgeD);
+else
+Out_Of_Range;
+end if;
+end if;
+end Time_Of;
+-----------------
+-- To_Duration --
+-----------------
+function To_Duration (TS : Time_Span) return Duration is
+begin
+return Duration (TS);
+end To_Duration;
+------------------
+-- To_Time_Span --
+------------------
+function To_Time_Span (D : Duration) return Time_Span is
+begin
+--  Note regarding AI-00432 requiring range checking on this conversion.
+--  In almost all versions of GNAT (and all to which this version of the
+--  Ada.Real_Time package apply), the range of Time_Span and Duration are
+--  the same, so there is no issue of overflow.
+return Time_Span (D);
+end To_Time_Span;
+begin
+--  Ensure that the tasking run time is initialized when using clock and/or
+--  delay operations. The initialization routine has the required machinery
+--  to prevent multiple calls to Initialize.
+System.Tasking.Initialize;
+end Ada.Real_Time;

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comparison gcc/ada/libgnarl/a-reatim.adb @ 111:04ced10e8804