opo.c File Reference

#include "espresso.h"

Go to the source code of this file.

Macros
#define	POW2(x)   (1 << (x))

Functions
static void	minimize ()
void	phase_assignment (pPLA PLA, int opo_strategy)
void	repeated_phase_assignment (pPLA PLA)
pcube	find_phase (pPLA PLA, int first_output, pcube phase1)
pcover	opo (pcube phase, pcover T, pcover D, pcover R, int first_output)
pset_family	opo_recur (pcover T, pcover D, pcube select, int offset, int first, int last)
pset_family	opo_leaf (pcover T, pset select, int out1, int out2)
void	output_phase_setup (INOUT pPLA PLA, int first_output)
pPLA	set_phase (INOUT pPLA PLA)
void	opoall (pPLA PLA, int first_output, int last_output, int opo_strategy)
static void	minimize (pPLA PLA)

Variables
static ABC_NAMESPACE_IMPL_START int	opo_no_make_sparse
static int	opo_repeated
static int	opo_exact

Macro Definition Documentation

#define POW2

(

x

)

(1 << (x))

Definition at line 539 of file opo.c.

Function Documentation

pcube find_phase	(	pPLA	PLA,
		int	first_output,
		pcube	phase1
	)

Definition at line 129 of file opo.c.

{
    pcube phase;
    pPLA PLA1;

    phase = set_save(cube.fullset);

    /* setup the double-phase characteristic function, resize the cube */
    PLA1 = new_PLA();
    PLA1->F = sf_save(PLA->F);
    PLA1->R = sf_save(PLA->R);
    PLA1->D = sf_save(PLA->D);
    if (phase1 != NULL) {
    PLA1->phase = set_save(phase1);
    (void) set_phase(PLA1);
    }
    EXEC_S(output_phase_setup(PLA1, first_output), "OPO-SETUP ", PLA1->F);

    /* minimize the double-phase function */
    minimize(PLA1);

    /* set the proper phases according to what gives a minimum solution */
    EXEC_S(PLA1->F = opo(phase, PLA1->F, PLA1->D, PLA1->R, first_output),
        "OPO       ", PLA1->F);
    free_PLA(PLA1);

    /* set the cube structure to reflect the old size */
    setdown_cube();
    cube.part_size[cube.output] -=
    (cube.part_size[cube.output] - first_output) / 2;
    cube_setup();

    return phase;
}

static void minimize ( )

static

static void minimize ( pPLA  PLA )

static

Definition at line 619 of file opo.c.

{
    if (opo_exact) {
    EXEC_S(PLA->F = minimize_exact(PLA->F,PLA->D,PLA->R,1), "EXACT", PLA->F);
    } else {
    EXEC_S(PLA->F = espresso(PLA->F, PLA->D, PLA->R), "ESPRESSO  ",PLA->F);
    }
}

pcover opo	(	pcube	phase,
		pcover	T,
		pcover	D,
		pcover	R,
		int	first_output
	)

Definition at line 173 of file opo.c.

{
    int offset, output, i, last_output, ind;
    pset pdest, select, p, p1, last, last1, not_covered, tmp;
    pset_family temp, T1, T2;

    /* must select all primes for outputs [0 .. first_output-1] */
    select = set_full(T->count);
    for(output = 0; output < first_output; output++) {
    ind = cube.first_part[cube.output] + output;
    foreachi_set(T, i, p) {
        if (is_in_set(p, ind)) {
        set_remove(select, i);
        }
    }
    }

    /* Recursively perform the intersections */
    offset = (cube.part_size[cube.output] - first_output) / 2;
    last_output = first_output + offset - 1;
    temp = opo_recur(T, D, select, offset, first_output, last_output);

    /* largest set is on top -- select primes which are inferred from it */
    pdest = temp->data;
    T1 = new_cover(T->count);
    foreachi_set(T, i, p) {
    if (! is_in_set(pdest, i)) {
        T1 = sf_addset(T1, p);
    }
    }

    set_free(select);
    sf_free(temp);

    /* finding phases is difficult -- see which functions are not covered */
    T2 = complement(cube1list(T1));
    not_covered = new_cube();
    tmp = new_cube();
    foreach_set(T, last, p) {
    foreach_set(T2, last1, p1) {
        if (cdist0(p, p1)) {
        (void) set_or(not_covered, not_covered, set_and(tmp, p, p1));
        }
    }
    }
    free_cover(T);
    free_cover(T2);
    set_free(tmp);

    /* Now reflect the phase choice in a single cube */
    for(output = first_output; output <= last_output; output++) {
    ind = cube.first_part[cube.output] + output;
    if (is_in_set(not_covered, ind)) {
        if (is_in_set(not_covered, ind + offset)) {
        fatal("error in output phase assignment");
        } else {
        set_remove(phase, ind);
        }
    }
    }
    set_free(not_covered);
    return T1;
}

pset_family opo_leaf	(	pcover	T,
		pset	select,
		int	out1,
		int	out2
	)

Definition at line 278 of file opo.c.

{
    register pset_family temp;
    register pset p, pdest;
    register int i;

    out1 += cube.first_part[cube.output];
    out2 += cube.first_part[cube.output];

    /* Allocate space for the result */
    temp = sf_new(2, T->count);

    /* Find which primes are needed for the ON-set of this fct */
    pdest = GETSET(temp, temp->count++);
    (void) set_copy(pdest, select);
    foreachi_set(T, i, p) {
    if (is_in_set(p, out1)) {
        set_remove(pdest, i);
    }
    }

    /* Find which primes are needed for the OFF-set of this fct */
    pdest = GETSET(temp, temp->count++);
    (void) set_copy(pdest, select);
    foreachi_set(T, i, p) {
    if (is_in_set(p, out2)) {
        set_remove(pdest, i);
    }
    }

    return temp;
}

pset_family opo_recur	(	pcover	T,
		pcover	D,
		pcube	select,
		int	offset,
		int	first,
		int	last
	)

Definition at line 240 of file opo.c.

{
    static int level = 0;
    int middle;
    pset_family sl, sr, temp;

    level++;
    if (first == last) {
#if 0
    if (opo_no_make_sparse) {
        temp = form_cover_table(T, D, select, first, first + offset);
    } else {
        temp = opo_leaf(T, select, first, first + offset);
    }
#else
    temp = opo_leaf(T, select, first, first + offset);
#endif
    } else {
    middle = (first + last) / 2;
    sl = opo_recur(T, D, select, offset, first, middle);
    sr = opo_recur(T, D, select, offset, middle+1, last);
    temp = unate_intersect(sl, sr, level == 1);
    if (trace) {
        printf("# OPO[%d]: %4d = %4d x %4d, time = %s\n", level - 1,
        temp->count, sl->count, sr->count, print_time(ptime()));
        (void) fflush(stdout);
    }
    free_cover(sl);
    free_cover(sr);
    }
    level--;
    return temp;
}

void opoall	(	pPLA	PLA,
		int	first_output,
		int	last_output,
		int	opo_strategy
	)

Definition at line 541 of file opo.c.

{
    pcover F, D, R, best_F, best_D, best_R;
    int i, j, ind, num;
    pcube bestphase;

    opo_exact = opo_strategy;

    if (PLA->phase != NULL) {
    set_free(PLA->phase);
    }

    bestphase = set_save(cube.fullset);
    best_F = sf_save(PLA->F);
    best_D = sf_save(PLA->D);
    best_R = sf_save(PLA->R);

    for(i = 0; i < POW2(last_output - first_output + 1); i++) {

    /* save the initial PLA covers */
    F = sf_save(PLA->F);
    D = sf_save(PLA->D);
    R = sf_save(PLA->R);

    /* compute the phase cube for this iteration */
    PLA->phase = set_save(cube.fullset);
    num = i;
    for(j = last_output; j >= first_output; j--) {
        if (num % 2 == 0) {
        ind = cube.first_part[cube.output] + j;
        set_remove(PLA->phase, ind);
        }
        num /= 2;
    }

    /* set the phase and minimize */
    (void) set_phase(PLA);
    printf("# phase is %s\n", pc1(PLA->phase));
    summary = TRUE;
    minimize(PLA);

    /* see if this is the best so far */
    if (PLA->F->count < best_F->count) {
        /* save new best solution */
        set_copy(bestphase, PLA->phase);
        sf_free(best_F);
        sf_free(best_D);
        sf_free(best_R);
        best_F = PLA->F;
        best_D = PLA->D;
        best_R = PLA->R;
    } else {
        /* throw away the solution */
        free_cover(PLA->F);
        free_cover(PLA->D);
        free_cover(PLA->R);
    }
    set_free(PLA->phase);

    /* restore the initial PLA covers */
    PLA->F = F;
    PLA->D = D;
    PLA->R = R;
    }

    /* one more minimization to restore the best answer */
    PLA->phase = bestphase;
    sf_free(PLA->F);
    sf_free(PLA->D);
    sf_free(PLA->R);
    PLA->F = best_F;
    PLA->D = best_D;
    PLA->R = best_R;
}

void output_phase_setup	(	INOUT pPLA	PLA,
		int	first_output
	)

Definition at line 417 of file opo.c.

{
    pcover F, R, D;
    pcube mask, mask1, last;
    int first_part, offset;
    bool save;
    register pcube p, pr, pf;
    register int i, last_part;

    if (cube.output == -1)
    fatal("output_phase_setup: must have an output");

    F = PLA->F;
    D = PLA->D;
    R = PLA->R;
    first_part = cube.first_part[cube.output] + first_output;
    last_part = cube.last_part[cube.output];
    offset = cube.part_size[cube.output] - first_output;

    /* Change the output size, setup the cube structure */
    setdown_cube();
    cube.part_size[cube.output] += offset;
    cube_setup();

    /* Create a mask to select that part of the cube which isn't changing */
    mask = set_save(cube.fullset);
    for(i = first_part; i < cube.size; i++)
    set_remove(mask, i);
    mask1 = set_save(mask);
    for(i = cube.first_part[cube.output]; i < first_part; i++) {
    set_remove(mask1, i);
    }

    PLA->F = new_cover(F->count + R->count);
    PLA->R = new_cover(F->count + R->count);
    PLA->D = new_cover(D->count);

    foreach_set(F, last, p) {
    pf = GETSET(PLA->F, (PLA->F)->count++);
    pr = GETSET(PLA->R, (PLA->R)->count++);
    INLINEset_and(pf, mask, p);
    INLINEset_and(pr, mask1, p);
    for(i = first_part; i <= last_part; i++)
        if (is_in_set(p, i))
        set_insert(pf, i);
    save = FALSE;
    for(i = first_part; i <= last_part; i++)
        if (is_in_set(p, i))
        save = TRUE, set_insert(pr, i+offset);
    if (! save) PLA->R->count--;
    }

    foreach_set(R, last, p) {
    pf = GETSET(PLA->F, (PLA->F)->count++);
    pr = GETSET(PLA->R, (PLA->R)->count++);
    INLINEset_and(pf, mask1, p);
    INLINEset_and(pr, mask, p);
    save = FALSE;
    for(i = first_part; i <= last_part; i++)
        if (is_in_set(p, i))
        save = TRUE, set_insert(pf, i+offset);
    if (! save) PLA->F->count--;
    for(i = first_part; i <= last_part; i++)
        if (is_in_set(p, i))
        set_insert(pr, i);
    }

    foreach_set(D, last, p) {
    pf = GETSET(PLA->D, (PLA->D)->count++);
    INLINEset_and(pf, mask, p);
    for(i = first_part; i <= last_part; i++)
        if (is_in_set(p, i)) {
        set_insert(pf, i);
        set_insert(pf, i+offset);
        }
    }

    free_cover(F);
    free_cover(D);
    free_cover(R);
    set_free(mask);
    set_free(mask1);
}

void phase_assignment	(	pPLA	PLA,
		int	opo_strategy
	)

Definition at line 67 of file opo.c.

{
    opo_no_make_sparse = opo_strategy % 2;
    skip_make_sparse = opo_no_make_sparse;
    opo_repeated = (opo_strategy / 2) % 2;
    opo_exact = (opo_strategy / 4) % 2;

    /* Determine a phase assignment */
    if (PLA->phase != NULL) {
    FREE(PLA->phase);
    }

    if (opo_repeated) {
    PLA->phase = set_save(cube.fullset);
    repeated_phase_assignment(PLA);
    } else {
    PLA->phase = find_phase(PLA, 0, (pcube) NULL);
    }

    /* Now minimize with this assignment */
    skip_make_sparse = FALSE;
    (void) set_phase(PLA);
    minimize(PLA);
}

void repeated_phase_assignment

(

pPLA

PLA

)

Definition at line 99 of file opo.c.

{
    int i;
    pcube phase;

    for(i = 0; i < cube.part_size[cube.output]; i++) {

    /* Find best assignment for all undecided outputs */
    phase = find_phase(PLA, i, PLA->phase);

    /* Commit for only a single output ... */
    if (! is_in_set(phase, cube.first_part[cube.output] + i)) {
        set_remove(PLA->phase, cube.first_part[cube.output] + i);
    }

    if (trace || summary) {
        printf("\nOPO loop for output #%d\n", i);
        printf("PLA->phase is %s\n", pc1(PLA->phase));
        printf("phase      is %s\n", pc1(phase));
    }
    set_free(phase);
    }
}

pPLA set_phase

(

INOUT pPLA

PLA

)

Definition at line 507 of file opo.c.

{
    pcover F1, R1;
    register pcube last, p, outmask;
    register pcube temp=cube.temp[0], phase=PLA->phase, phase1=cube.temp[1];

    outmask = cube.var_mask[cube.num_vars - 1];
    set_diff(phase1, outmask, phase);
    set_or(phase1, set_diff(temp, cube.fullset, outmask), phase1);
    F1 = new_cover((PLA->F)->count + (PLA->R)->count);
    R1 = new_cover((PLA->F)->count + (PLA->R)->count);

    foreach_set(PLA->F, last, p) {
    if (! setp_disjoint(set_and(temp, p, phase), outmask))
        set_copy(GETSET(F1, F1->count++), temp);
    if (! setp_disjoint(set_and(temp, p, phase1), outmask))
        set_copy(GETSET(R1, R1->count++), temp);
    }
    foreach_set(PLA->R, last, p) {
    if (! setp_disjoint(set_and(temp, p, phase), outmask))
        set_copy(GETSET(R1, R1->count++), temp);
    if (! setp_disjoint(set_and(temp, p, phase1), outmask))
        set_copy(GETSET(F1, F1->count++), temp);
    }
    free_cover(PLA->F);
    free_cover(PLA->R);
    PLA->F = F1;
    PLA->R = R1;
    return PLA;
}

Variable Documentation

int opo_exact

static

Definition at line 64 of file opo.c.

ABC_NAMESPACE_IMPL_START int opo_no_make_sparse

static

Definition at line 62 of file opo.c.

int opo_repeated

static

Definition at line 63 of file opo.c.