[Bug libfortran/48925] New: Code cleanup in write_float.def

[Bug libfortran/48925] New: Code cleanup in write_float.def

[thenlich at users dot sourceforge.net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48925

           Summary: Code cleanup in write_float.def
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: libfortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: thenlich@users.sourceforge.net


For improvement in code quality and possible future modifications, I suggest to
separate the steps "digit generation" and "number formatting" into separate
functions.

1. There should be a function "Digit generation".
Input:
- a floting-point number (e.g. -.123456789E+12)
- the rounding mode (up/down etc.)
- mode: fixed-point (F editing), or floating-point (E/ES/G), or engineering
(EN) 
- number of significant digits (floating-point), number of decimal digits (F)

Output:
- a string with the digits of the rounded significand (e.g. "123457")
- an integer exponent (e.g. 12), or position of the decimal separator
- the sign flag (- or +)

2. There should be a function "number formatting"
Input:
- s.a. Output
- the edit descriptor (F/E/G...)
- Field width w and number of requested digits d

Output:
- A buffer with the formatted number (e.g. "   +1.23457E+011")

Function 2 is independent of the floating-point precision, so we don't need it
four times for all the different real kinds, only one time.

[Bug libfortran/48925] Code cleanup in write_float.def

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48925

--- Comment #1 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2011-05-25 01:34:19 UTC ---
I will be doing some things with this, maybe not exactly as suggested.

[Bug libfortran/48925] Code cleanup in write_float.def

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48925

Dominique d'Humieres <dominiq at lps dot ens.fr> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-01-14
     Ever confirmed|0                           |1

--- Comment #2 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
For having looked at the code for pr59774, I agree that
libgfortran/io/write_float.def badly needs some cleaning in next stage 1.

[Bug libfortran/48925] Code cleanup in write_float.def

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48925

--- Comment #3 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
Lets first fix the known bugs so we have a good baseline.  Then we can
reorganize the code with little impact And with with additional test cases fro
those bug fixes, we minimize our probability of regressions.