diff options
Diffstat (limited to 'gcc/ada/libgnat/s-widthu.ads')
-rw-r--r-- | gcc/ada/libgnat/s-widthu.ads | 53 |
1 files changed, 1 insertions, 52 deletions
diff --git a/gcc/ada/libgnat/s-widthu.ads b/gcc/ada/libgnat/s-widthu.ads index 56da0a2..076dace 100644 --- a/gcc/ada/libgnat/s-widthu.ads +++ b/gcc/ada/libgnat/s-widthu.ads @@ -29,65 +29,14 @@ -- -- ------------------------------------------------------------------------------ --- Preconditions in this unit are meant for analysis only, not for run-time --- checking, so that the expected exceptions are raised. This is enforced by --- setting the corresponding assertion policy to Ignore. Postconditions and --- contract cases should not be executed at runtime as well, in order not to --- slow down the execution of these functions. - -pragma Assertion_Policy (Pre => Ignore, - Post => Ignore, - Contract_Cases => Ignore, - Ghost => Ignore, - Subprogram_Variant => Ignore); - -- Compute Width attribute for non-static type derived from a modular integer -- type. The arguments Lo, Hi are the bounds of the type. -with Ada.Numerics.Big_Numbers.Big_Integers_Ghost; - generic - type Uns is mod <>; package System.Width_U with Pure is - package BI_Ghost renames Ada.Numerics.Big_Numbers.Big_Integers_Ghost; - subtype Big_Integer is BI_Ghost.Big_Integer with Ghost; - subtype Big_Natural is BI_Ghost.Big_Natural with Ghost; - subtype Big_Positive is BI_Ghost.Big_Positive with Ghost; - use type BI_Ghost.Big_Integer; - - package Unsigned_Conversion is - new BI_Ghost.Unsigned_Conversions (Int => Uns); - - function Big (Arg : Uns) return Big_Integer renames - Unsigned_Conversion.To_Big_Integer; - - Big_10 : constant Big_Integer := Big (Uns'(10)) with Ghost; - - -- Maximum value of exponent for 10 that fits in Uns'Base - function Max_Log10 return Natural is - (case Uns'Base'Size is - when 8 => 2, - when 16 => 4, - when 32 => 9, - when 64 => 19, - when 128 => 38, - when others => raise Program_Error) - with Ghost; - - function Width (Lo, Hi : Uns) return Natural - with - Post => - (declare - W : constant Natural := System.Width_U.Width'Result; - begin - (if Lo > Hi then W = 0 - else W > 0 - and then W <= Max_Log10 + 2 - and then Big (Lo) < Big_10 ** (W - 1) - and then Big (Hi) < Big_10 ** (W - 1))); - + function Width (Lo, Hi : Uns) return Natural; end System.Width_U; |