diff options
Diffstat (limited to 'gcc/ada/s-fatgen.adb')
| -rw-r--r-- | gcc/ada/s-fatgen.adb | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/gcc/ada/s-fatgen.adb b/gcc/ada/s-fatgen.adb index cf7e4254b66..1288904278d 100644 --- a/gcc/ada/s-fatgen.adb +++ b/gcc/ada/s-fatgen.adb @@ -6,7 +6,7 @@ -- -- -- B o d y -- -- -- --- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2010, 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- -- @@ -162,13 +162,12 @@ package body System.Fat_Gen is begin if X = 0.0 then + + -- The normalized exponent of zero is zero, see RM A.5.2(15) + Frac := X; Expo := 0; - -- More useful would be defining Expo to be T'Machine_Emin - 1 or - -- T'Machine_Emin - T'Machine_Mantissa, which would preserve - -- monotonicity of the exponent function ??? - -- Check for infinities, transfinites, whatnot elsif X > T'Safe_Last then @@ -205,6 +204,7 @@ package body System.Fat_Gen is end if; -- Ax < R_Power (N) + end loop; -- 1 <= Ax < Rad @@ -229,6 +229,7 @@ package body System.Fat_Gen is end if; -- R_Neg_Power (N) <= Ax < 1 + end loop; end if; @@ -553,8 +554,8 @@ package body System.Fat_Gen is -- Scaling -- ------------- - -- Return x * rad ** adjustment quickly, - -- or quietly underflow to zero, or overflow naturally. + -- Return x * rad ** adjustment quickly, or quietly underflow to zero, + -- or overflow naturally. function Scaling (X : T; Adjustment : UI) return T is begin @@ -586,6 +587,7 @@ package body System.Fat_Gen is end if; -- -Log_Power (N) < Ex <= 0 + end loop; -- Ex = 0 @@ -611,6 +613,7 @@ package body System.Fat_Gen is end loop; -- Ex = 0 + end if; return Y; @@ -648,13 +651,13 @@ package body System.Fat_Gen is else Decompose (X, X_Frac, X_Exp); - -- A special case, if the number we had was a negative power of - -- two, then we want to add half of what we would otherwise add, - -- since the exponent is going to be reduced. + -- A special case, if the number we had was a negative power of two, + -- then we want to add half of what we would otherwise add, since the + -- exponent is going to be reduced. -- Note that X_Frac has the same sign as X, so if X_Frac is -0.5, - -- then we know that we have a negative number (and hence a - -- negative power of 2). + -- then we know that we have a negative number (and hence a negative + -- power of 2). if X_Frac = -0.5 then return X + Gradual_Scaling (X_Exp - T'Machine_Mantissa - 1); @@ -779,8 +782,8 @@ package body System.Fat_Gen is -- one read, but small enough so that all floating point object sizes -- are a multiple of the Float_Word'Size. - -- The following conditions must be met for all possible - -- instantiations of the attributes package: + -- The following conditions must be met for all possible instantiations + -- of the attributes package: -- - T'Size is an integral multiple of Float_Word'Size @@ -795,9 +798,11 @@ package body System.Fat_Gen is type Rep_Index is range 0 .. 7; Rep_Words : constant Positive := - (T'Size + Float_Word'Size - 1) / Float_Word'Size; - Rep_Last : constant Rep_Index := Rep_Index'Min - (Rep_Index (Rep_Words - 1), (T'Mantissa + 16) / Float_Word'Size); + (T'Size + Float_Word'Size - 1) / Float_Word'Size; + Rep_Last : constant Rep_Index := + Rep_Index'Min + (Rep_Index (Rep_Words - 1), + (T'Mantissa + 16) / Float_Word'Size); -- Determine the number of Float_Words needed for representing the -- entire floating-point value. Do not take into account excessive -- padding, as occurs on IA-64 where 80 bits floats get padded to 128 |