ADDA > iterative.c > ITER_FUNC(BCGS2) / function call

My_Environment

Ubuntu 14.04 LTS Japanese Remix
on VMWare Fusion v8.5.2 (4635224)
on OS X El Captian v10.11.4

GNU bash, version 4.3.11(1)-release

gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4 
(also for g++)
ADDA v.1.3b6

This article is related to ADDA (light scattering simulator based on the discrete dipole approximation).

In the source files, I found itertive.c.
https://github.com/adda-team/adda/blob/master/src/iterative.c

ITER_FUNC(BCGS2)

In the iterative.c, I found the followings:

ITER_FUNC(BCGS2);
ITER_FUNC(BiCG_CS);
ITER_FUNC(BiCGStab);
ITER_FUNC(CGNR);
ITER_FUNC(CSYM);
ITER_FUNC(QMR_CS);
ITER_FUNC(QMR_CS_2);

The ITER_FUNC is a macro defined as followings

#define ITER_FUNC(name) static void name(const enum phase ph)

I am not sure, but this seems a means to show explicitly the groups of iterative solvers, rather than to name using prefix (e.g. ITER_BCGS2(), ITER_BiGC_CS() etc).

This also enforces to use enum elements (e.g. BCGS2, BiGC_CS), which are used in other parts of the code.

function call

It seems that functions defined using ITER_FUNC() are called through:

iterative.c

static const struct iter_params_struct params[]={
    {IT_BCGS2,15000,2,1,BCGS2},
    {IT_BICG_CS,50000,1,0,BiCG_CS},
    {IT_BICGSTAB,30000,3,3,BiCGStab},
    {IT_CGNR,10,1,0,CGNR},
    {IT_CSYM,10,6,2,CSYM},
    {IT_QMR_CS,50000,8,3,QMR_CS},
    {IT_QMR_CS_2,50000,5,2,QMR_CS_2}
...
};

where struct iter_params_struct are defined as

iterative.c

struct iter_params_struct {
    enum iter meth;   // identifier
    int mc;           // maximum allowed number of iterations without residual decrease
    int sc_N;         // number of additional scalars to describe the state
    int vec_N;        // number of additional vectors to describe the state
    void (*func)(const enum phase); // pointer to implementation of the iterative solver
};