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Diffstat (limited to 'gcc/ada/s-valrea.adb')
| -rw-r--r-- | gcc/ada/s-valrea.adb | 415 |
1 files changed, 0 insertions, 415 deletions
diff --git a/gcc/ada/s-valrea.adb b/gcc/ada/s-valrea.adb deleted file mode 100644 index 7284e60..0000000 --- a/gcc/ada/s-valrea.adb +++ /dev/null @@ -1,415 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S Y S T E M . V A L _ R E A L -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2015, 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 System.Powten_Table; use System.Powten_Table; -with System.Val_Util; use System.Val_Util; -with System.Float_Control; - -package body System.Val_Real is - - --------------- - -- Scan_Real -- - --------------- - - function Scan_Real - (Str : String; - Ptr : not null access Integer; - Max : Integer) return Long_Long_Float - is - P : Integer; - -- Local copy of string pointer - - Base : Long_Long_Float; - -- Base value - - Uval : Long_Long_Float; - -- Accumulated float result - - subtype Digs is Character range '0' .. '9'; - -- Used to check for decimal digit - - Scale : Integer := 0; - -- Power of Base to multiply result by - - Start : Positive; - -- Position of starting non-blank character - - Minus : Boolean; - -- Set to True if minus sign is present, otherwise to False - - Bad_Base : Boolean := False; - -- Set True if Base out of range or if out of range digit - - After_Point : Natural := 0; - -- Set to 1 after the point - - Num_Saved_Zeroes : Natural := 0; - -- This counts zeroes after the decimal point. A non-zero value means - -- that this number of previously scanned digits are zero. If the end - -- of the number is reached, these zeroes are simply discarded, which - -- ensures that trailing zeroes after the point never affect the value - -- (which might otherwise happen as a result of rounding). With this - -- processing in place, we can ensure that, for example, we get the - -- same exact result from 1.0E+49 and 1.0000000E+49. This is not - -- necessarily required in a case like this where the result is not - -- a machine number, but it is certainly a desirable behavior. - - procedure Scanf; - -- Scans integer literal value starting at current character position. - -- For each digit encountered, Uval is multiplied by 10.0, and the new - -- digit value is incremented. In addition Scale is decremented for each - -- digit encountered if we are after the point (After_Point = 1). The - -- longest possible syntactically valid numeral is scanned out, and on - -- return P points past the last character. On entry, the current - -- character is known to be a digit, so a numeral is definitely present. - - ----------- - -- Scanf -- - ----------- - - procedure Scanf is - Digit : Natural; - - begin - loop - Digit := Character'Pos (Str (P)) - Character'Pos ('0'); - P := P + 1; - - -- Save up trailing zeroes after the decimal point - - if Digit = 0 and then After_Point = 1 then - Num_Saved_Zeroes := Num_Saved_Zeroes + 1; - - -- Here for a non-zero digit - - else - -- First deal with any previously saved zeroes - - if Num_Saved_Zeroes /= 0 then - while Num_Saved_Zeroes > Maxpow loop - Uval := Uval * Powten (Maxpow); - Num_Saved_Zeroes := Num_Saved_Zeroes - Maxpow; - Scale := Scale - Maxpow; - end loop; - - Uval := Uval * Powten (Num_Saved_Zeroes); - Scale := Scale - Num_Saved_Zeroes; - - Num_Saved_Zeroes := 0; - end if; - - -- Accumulate new digit - - Uval := Uval * 10.0 + Long_Long_Float (Digit); - Scale := Scale - After_Point; - end if; - - -- Done if end of input field - - if P > Max then - return; - - -- Check next character - - elsif Str (P) not in Digs then - if Str (P) = '_' then - Scan_Underscore (Str, P, Ptr, Max, False); - else - return; - end if; - end if; - end loop; - end Scanf; - - -- Start of processing for System.Scan_Real - - begin - -- We do not tolerate strings with Str'Last = Positive'Last - - if Str'Last = Positive'Last then - raise Program_Error with - "string upper bound is Positive'Last, not supported"; - end if; - - -- We call the floating-point processor reset routine so that we can - -- be sure the floating-point processor is properly set for conversion - -- calls. This is notably need on Windows, where calls to the operating - -- system randomly reset the processor into 64-bit mode. - - System.Float_Control.Reset; - - Scan_Sign (Str, Ptr, Max, Minus, Start); - P := Ptr.all; - Ptr.all := Start; - - -- If digit, scan numeral before point - - if Str (P) in Digs then - Uval := 0.0; - Scanf; - - -- Initial point, allowed only if followed by digit (RM 3.5(47)) - - elsif Str (P) = '.' - and then P < Max - and then Str (P + 1) in Digs - then - Uval := 0.0; - - -- Any other initial character is an error - - else - Bad_Value (Str); - end if; - - -- Deal with based case. We reognize either the standard '#' or the - -- allowed alternative replacement ':' (see RM J.2(3)). - - if P < Max and then (Str (P) = '#' or else Str (P) = ':') then - declare - Base_Char : constant Character := Str (P); - Digit : Natural; - Fdigit : Long_Long_Float; - - begin - -- Set bad base if out of range, and use safe base of 16.0, - -- to guard against division by zero in the loop below. - - if Uval < 2.0 or else Uval > 16.0 then - Bad_Base := True; - Uval := 16.0; - end if; - - Base := Uval; - Uval := 0.0; - P := P + 1; - - -- Special check to allow initial point (RM 3.5(49)) - - if Str (P) = '.' then - After_Point := 1; - P := P + 1; - end if; - - -- Loop to scan digits of based number. On entry to the loop we - -- must have a valid digit. If we don't, then we have an illegal - -- floating-point value, and we raise Constraint_Error, note that - -- Ptr at this stage was reset to the proper (Start) value. - - loop - if P > Max then - Bad_Value (Str); - - elsif Str (P) in Digs then - Digit := Character'Pos (Str (P)) - Character'Pos ('0'); - - elsif Str (P) in 'A' .. 'F' then - Digit := - Character'Pos (Str (P)) - (Character'Pos ('A') - 10); - - elsif Str (P) in 'a' .. 'f' then - Digit := - Character'Pos (Str (P)) - (Character'Pos ('a') - 10); - - else - Bad_Value (Str); - end if; - - -- Save up trailing zeroes after the decimal point - - if Digit = 0 and then After_Point = 1 then - Num_Saved_Zeroes := Num_Saved_Zeroes + 1; - - -- Here for a non-zero digit - - else - -- First deal with any previously saved zeroes - - if Num_Saved_Zeroes /= 0 then - Uval := Uval * Base ** Num_Saved_Zeroes; - Scale := Scale - Num_Saved_Zeroes; - Num_Saved_Zeroes := 0; - end if; - - -- Now accumulate the new digit - - Fdigit := Long_Long_Float (Digit); - - if Fdigit >= Base then - Bad_Base := True; - else - Scale := Scale - After_Point; - Uval := Uval * Base + Fdigit; - end if; - end if; - - P := P + 1; - - if P > Max then - Bad_Value (Str); - - elsif Str (P) = '_' then - Scan_Underscore (Str, P, Ptr, Max, True); - - else - -- Skip past period after digit. Note that the processing - -- here will permit either a digit after the period, or the - -- terminating base character, as allowed in (RM 3.5(48)) - - if Str (P) = '.' and then After_Point = 0 then - P := P + 1; - After_Point := 1; - - if P > Max then - Bad_Value (Str); - end if; - end if; - - exit when Str (P) = Base_Char; - end if; - end loop; - - -- Based number successfully scanned out (point was found) - - Ptr.all := P + 1; - end; - - -- Non-based case, check for being at decimal point now. Note that - -- in Ada 95, we do not insist on a decimal point being present - - else - Base := 10.0; - After_Point := 1; - - if P <= Max and then Str (P) = '.' then - P := P + 1; - - -- Scan digits after point if any are present (RM 3.5(46)) - - if P <= Max and then Str (P) in Digs then - Scanf; - end if; - end if; - - Ptr.all := P; - end if; - - -- At this point, we have Uval containing the digits of the value as - -- an integer, and Scale indicates the negative of the number of digits - -- after the point. Base contains the base value (an integral value in - -- the range 2.0 .. 16.0). Test for exponent, must be at least one - -- character after the E for the exponent to be valid. - - Scale := Scale + Scan_Exponent (Str, Ptr, Max, Real => True); - - -- At this point the exponent has been scanned if one is present and - -- Scale is adjusted to include the exponent value. Uval contains the - -- the integral value which is to be multiplied by Base ** Scale. - - -- If base is not 10, use exponentiation for scaling - - if Base /= 10.0 then - Uval := Uval * Base ** Scale; - - -- For base 10, use power of ten table, repeatedly if necessary - - elsif Scale > 0 then - while Scale > Maxpow loop - Uval := Uval * Powten (Maxpow); - Scale := Scale - Maxpow; - end loop; - - -- Note that we still know that Scale > 0, since the loop - -- above leaves Scale in the range 1 .. Maxpow. - - Uval := Uval * Powten (Scale); - - elsif Scale < 0 then - while (-Scale) > Maxpow loop - Uval := Uval / Powten (Maxpow); - Scale := Scale + Maxpow; - end loop; - - -- Note that we still know that Scale < 0, since the loop - -- above leaves Scale in the range -Maxpow .. -1. - - Uval := Uval / Powten (-Scale); - end if; - - -- Here is where we check for a bad based number - - if Bad_Base then - Bad_Value (Str); - - -- If OK, then deal with initial minus sign, note that this processing - -- is done even if Uval is zero, so that -0.0 is correctly interpreted. - - else - if Minus then - return -Uval; - else - return Uval; - end if; - end if; - end Scan_Real; - - ---------------- - -- Value_Real -- - ---------------- - - function Value_Real (Str : String) return Long_Long_Float is - begin - -- We have to special case Str'Last = Positive'Last because the normal - -- circuit ends up setting P to Str'Last + 1 which is out of bounds. We - -- deal with this by converting to a subtype which fixes the bounds. - - if Str'Last = Positive'Last then - declare - subtype NT is String (1 .. Str'Length); - begin - return Value_Real (NT (Str)); - end; - - -- Normal case where Str'Last < Positive'Last - - else - declare - V : Long_Long_Float; - P : aliased Integer := Str'First; - begin - V := Scan_Real (Str, P'Access, Str'Last); - Scan_Trailing_Blanks (Str, P); - return V; - end; - end if; - end Value_Real; - -end System.Val_Real; |