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From: Tejas Joshi <tejasjoshi9673@gmail.com>
Date: Fri, 25 Jan 2019 19:52:00 -0000
Message-ID: <CACMrGjC6NP5CE17M1gDf09B+2Gbufp3offHQmRX1D8hiWGrQ2Q@mail.gmail.com>
Subject: Re: About GSOC.
To: gcc@gcc.gnu.org
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It took some time to get know using GDB, but upto some end I got it to
work. The enum real_value_class is used to classify the number into
zero, normal, infinity and NaN.
This class is represented by r->cl in real_value and values in struct
real_value are used as flags or representations while string to real
conversion (real_from_string) in real.c and other functions. The
decimal/hex string value is converted into real in real_from_string
function with byte-byte comparison which also include mpfr. (Correct
me if I am wrong.) What is the significance of mpfr related to these
internal representations?
Thanks.

-Tejas

On Wed, 23 Jan 2019 at 23:06, Joseph Myers <joseph@codesourcery.com> wrote:
>
> On Wed, 23 Jan 2019, Tejas Joshi wrote:
>
> > But I really dont know how to inspect a file like real.h (real_value)/real.c?
>
> Use cc1 to build a test program with selected floating-point constants in
> it.  Set breakpoints on appropriate functions in real.c (e.g. related to
> converting strings for real constants into the internal representation).
> Look at the representation produced for those constants to determine the
> particular conventions being used.
>
> --
> Joseph S. Myers
> joseph@codesourcery.com