_mod_SxS_ sometimes behaves as _aplmod_SxS_

Modulo is supposed to be equal to the c modulo in that -1 % 3 = -1.

When running the below program, 2 is printed instead, as if _aplmod_SxS_ were called.

int main ()
{
    StdIO::print (_mod_SxS_( _neg_S_(1), 3));
    return 0;
}

Output of sac2c -V:

sac2c 1.3.3-MijasCosta-1047-g0c4a5
build-type: RELEASE
built-by: "mverloop" at 2023-02-06T10:27:54

added bug label

assigned to @sbs

mentioned in merge request !217 (merged)

The problem is that our constantfolder is using the same functionality for both of them :-(

constant *
COmod (constant *a, constant *b, constant *tmp1)
{
    constant *res;

    DBUG_ENTER ();
    res = COzip (global.zipcv_mod, a, b, T_unknown);
    DBUG_EXECUTE (COINTdbugPrintBinOp ("COmod", a, b, res));
    DBUG_RETURN (res);
}

/******************************************************************************
 *
 * function:
 *    constant *COaplmod( constant *a, constant *b)
 *
 * description:
 *    returns a constant whose elements are the elementwise modulo of a and b,
 *    provided that    either shape(a) == shape(b),
 *                     or at least one of { a, b } is scalar
 *
 *    This is for the ISO Standard N8485 aplmod() function.
 *
 ******************************************************************************/

constant *
COaplmod (constant *a, constant *b, constant *tmp1)
{
    constant *res;

    DBUG_ENTER ();
    res = COzip (global.zipcv_mod, a, b, T_unknown);
    DBUG_EXECUTE (COINTdbugPrintBinOp ("COaplmod", a, b, res));
    DBUG_RETURN (res);
}

closed via commit a112d18c

mentioned in commit fcd63e2b