boolean try_breadth_first_route (struct s_router_opts router_opts,
t_ivec **clb_opins_used_locally) {
/* Iterated maze router ala Pathfinder Negotiated Congestion algorithm, *
* (FPGA 95 p. 111). Returns TRUE if it can route this FPGA, FALSE if *
* it can't. */
float pres_fac;
boolean success, is_routable, rip_up_local_opins;
int itry, inet;
/* Usually the first iteration uses a very small (or 0) pres_fac to find *
* the shortest path and get a congestion map. For fast compiles, I set *
* pres_fac high even for the first iteration. */
pres_fac = router_opts.first_iter_pres_fac;
for (itry=1;itry<=router_opts.max_router_iterations;itry++) {
for (inet=0;inet<num_nets;inet++) {
/* Added by Wei */
if (is_folding)
{
if (current_stage != num_stage)
{
if ((inet<num_net_per_stage[current_stage-1].begin)||(inet>=num_net_per_stage[current_stage].begin))
continue;
}
else
{
if (inet<num_net_per_stage[current_stage-1].begin)
continue;
}
}
printf("The net is %d\n",inet);
if (is_global[inet] == FALSE) { /* Skip global nets. */
pathfinder_update_one_cost (trace_head[inet], -1, pres_fac);
is_routable = breadth_first_route_net (inet, router_opts.bend_cost);
/* Impossible to route? (disconnected rr_graph) */
if (!is_routable) {
printf ("Routing failed.\n");
return (FALSE);
}
pathfinder_update_one_cost (trace_head[inet], 1, pres_fac);
}
}
/* Make sure any CLB OPINs used up by subblocks being hooked directly *
* to them are reserved for that purpose. */
if (itry == 1)
rip_up_local_opins = FALSE;
else
rip_up_local_opins = TRUE;
reserve_locally_used_opins (pres_fac, rip_up_local_opins,
clb_opins_used_locally);
success = feasible_routing ();
if (success) {
printf("Successfully routed after %d routing iterations.\n", itry);
return (TRUE);
}
if (itry == 1)
pres_fac = router_opts.initial_pres_fac;
else
pres_fac *= router_opts.pres_fac_mult;
pathfinder_update_cost (pres_fac, router_opts.acc_fac);
}
printf ("Routing failed.\n");
return (FALSE);
}
void check_route(enum e_route_type route_type, int num_switch,
t_ivec ** clb_opins_used_locally) {
/* This routine checks that a routing: (1) Describes a properly *
* connected path for each net, (2) this path connects all the *
* pins spanned by that net, and (3) that no routing resources are *
* oversubscribed (the occupancy of everything is recomputed from *
* scratch). */
int inet, ipin, max_pins, inode, prev_node;
boolean valid, connects;
boolean * connected_to_route; /* [0 .. num_rr_nodes-1] */
struct s_trace *tptr;
boolean * pin_done;
vpr_printf(TIO_MESSAGE_INFO, "\n");
vpr_printf(TIO_MESSAGE_INFO, "Checking to ensure routing is legal...\n");
/* Recompute the occupancy from scratch and check for overuse of routing *
* resources. This was already checked in order to determine that this *
* is a successful routing, but I want to double check it here. */
recompute_occupancy_from_scratch(clb_opins_used_locally);
valid = feasible_routing();
if (valid == FALSE) {
vpr_printf(TIO_MESSAGE_ERROR, "Error in check_route -- routing resources are overused.\n");
exit(1);
}
check_locally_used_clb_opins(clb_opins_used_locally, route_type);
connected_to_route = (boolean *) my_calloc(num_rr_nodes, sizeof(boolean));
max_pins = 0;
for (inet = 0; inet < num_nets; inet++)
max_pins = std::max(max_pins, (clb_net[inet].num_sinks + 1));
pin_done = (boolean *) my_malloc(max_pins * sizeof(boolean));
/* Now check that all nets are indeed connected. */
for (inet = 0; inet < num_nets; inet++) {
if (clb_net[inet].is_global || clb_net[inet].num_sinks == 0) /* Skip global nets. */
continue;
for (ipin = 0; ipin < (clb_net[inet].num_sinks + 1); ipin++)
pin_done[ipin] = FALSE;
/* Check the SOURCE of the net. */
tptr = trace_head[inet];
if (tptr == NULL) {
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: net %d has no routing.\n", inet);
exit(1);
}
inode = tptr->index;
check_node_and_range(inode, route_type);
check_switch(tptr, num_switch);
connected_to_route[inode] = TRUE; /* Mark as in path. */
check_source(inode, inet);
pin_done[0] = TRUE;
prev_node = inode;
tptr = tptr->next;
/* Check the rest of the net */
while (tptr != NULL) {
inode = tptr->index;
check_node_and_range(inode, route_type);
check_switch(tptr, num_switch);
if (rr_node[prev_node].type == SINK) {
if (connected_to_route[inode] == FALSE) {
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: node %d does not link into existing routing for net %d.\n", inode, inet);
exit(1);
}
}
else {
connects = check_adjacent(prev_node, inode);
if (!connects) {
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: found non-adjacent segments in traceback while checking net %d.\n", inet);
exit(1);
}
if (connected_to_route[inode] && rr_node[inode].type != SINK) {
/* Note: Can get multiple connections to the same logically-equivalent *
* SINK in some logic blocks. */
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: net %d routing is not a tree.\n", inet);
exit(1);
}
connected_to_route[inode] = TRUE; /* Mark as in path. */
if (rr_node[inode].type == SINK)
check_sink(inode, inet, pin_done);
} /* End of prev_node type != SINK */
prev_node = inode;
tptr = tptr->next;
} /* End while */
if (rr_node[prev_node].type != SINK) {
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: net %d does not end with a SINK.\n", inet);
exit(1);
}
for (ipin = 0; ipin < (clb_net[inet].num_sinks + 1); ipin++) {
if (pin_done[ipin] == FALSE) {
vpr_printf(TIO_MESSAGE_ERROR, "in check_route: net %d does not connect to pin %d.\n", inet, ipin);
exit(1);
}
}
reset_flags(inet, connected_to_route);
} /* End for each net */
free(pin_done);
free(connected_to_route);
vpr_printf(TIO_MESSAGE_INFO, "Completed routing consistency check successfully.\n");
vpr_printf(TIO_MESSAGE_INFO, "\n");
}
boolean
try_directed_search_route(struct s_router_opts router_opts,
t_ivec ** fb_opins_used_locally,
int width_fac,
t_mst_edge ** mst)
{
/* Iterated maze router ala Pathfinder Negotiated Congestion algorithm, *
* (FPGA 95 p. 111). Returns TRUE if it can route this FPGA, FALSE if *
* it can't. */
float pres_fac;
boolean success, is_routable, rip_up_local_opins;
int itry, inet;
/* char msg[100]; */
/* mst not built as good as it should, ideally, just have it after placement once only
however, rr_node numbers changed when the channel width changes so forced to do it here */
if(mst)
{
for(inet = 0; inet < num_nets; inet++)
{
free(mst[inet]);
mst[inet] = get_mst_of_net(inet);
}
}
/* Usually the first iteration uses a very small (or 0) pres_fac to find *
* the shortest path and get a congestion map. For fast compiles, I set *
* pres_fac high even for the first iteration. */
pres_fac = router_opts.first_iter_pres_fac;
for(itry = 1; itry <= router_opts.max_router_iterations; itry++)
{
for(inet = 0; inet < num_nets; inet++)
{
if(net[inet].is_global == FALSE)
{ /* Skip global nets. */
is_routable =
directed_search_route_net(inet, pres_fac,
router_opts.
astar_fac,
router_opts.
bend_cost, mst);
/* Impossible to route? (disconnected rr_graph) */
if(!is_routable)
{
printf("Routing failed.\n");
return (FALSE);
}
}
}
/* Make sure any FB OPINs used up by subblocks being hooked directly *
* to them are reserved for that purpose. */
if(itry == 1)
rip_up_local_opins = FALSE;
else
rip_up_local_opins = TRUE;
reserve_locally_used_opins(pres_fac, rip_up_local_opins,
fb_opins_used_locally);
success = feasible_routing();
if(success)
{
printf
("Successfully routed after %d routing iterations by Directed Search.\n",
itry);
return (TRUE);
}
#if 0
else
{
sprintf(msg,
"After iteration %d routing failed (A*) with a channel width factor of %d and Fc_int of %d, Fs_int of %d.",
itry, width_fac, Fc_int, Fs_int);
init_draw_coords(pins_per_clb);
update_screen(MAJOR, msg, ROUTING, FALSE);
}
#endif
if(itry == 1)
{
pres_fac = router_opts.initial_pres_fac;
pathfinder_update_cost(pres_fac, 0.); /* Acc_fac=0 for first iter. */
}
else
{
pres_fac *= router_opts.pres_fac_mult;
pathfinder_update_cost(pres_fac, router_opts.acc_fac);
}
}
printf("Routing failed.\n");
return (FALSE);
}
boolean
try_directed_search_route(struct s_router_opts router_opts,
t_ivec ** clb_opins_used_locally,
int width_fac,
t_mst_edge ** mst)
{
/* Iterated maze router ala Pathfinder Negotiated Congestion algorithm, *
* (FPGA 95 p. 111). Returns TRUE if it can route this FPGA, FALSE if *
* it can't. */
float pres_fac;
boolean success, is_routable, rip_up_local_opins;
int itry, inet, i;
clock_t begin, end;
int bends;
int wirelength, total_wirelength, available_wirelength;
int segments;
float *sinks;
int *net_index;
sinks = my_malloc(sizeof(float) * num_nets);
net_index = my_malloc(sizeof(int) * num_nets);
for(i = 0; i < num_nets; i++) {
sinks[i] = clb_net[i].num_sinks;
net_index[i] = i;
}
heapsort(net_index, sinks, num_nets, 1);
/* char msg[100]; */
begin = clock();
/* mst not built as good as it should, ideally, just have it after placement once only
however, rr_node numbers changed when the channel width changes so forced to do it here */
if(mst)
{
for(inet = 0; inet < num_nets; inet++)
{
free(mst[inet]);
mst[inet] = get_mst_of_net(inet);
}
}
end = clock();
#ifdef CLOCKS_PER_SEC
printf("mst took %g seconds\n", (float)(end - begin) / CLOCKS_PER_SEC);
#else
printf("mst took %g seconds\n", (float)(end - begin) / CLK_PER_SEC);
#endif
/* Usually the first iteration uses a very small (or 0) pres_fac to find *
* the shortest path and get a congestion map. For fast compiles, I set *
* pres_fac high even for the first iteration. */
pres_fac = router_opts.first_iter_pres_fac;
for(itry = 1; itry <= router_opts.max_router_iterations; itry++)
{
begin = clock();
printf("routing iteration %d\n", itry);
for(i = 0; i < num_nets; i++)
{
inet = net_index[i];
if(clb_net[inet].is_global == FALSE && clb_net[inet].num_sinks != 0)
{ /* Skip global nets and empty nets (empty nets are already reserved using reserve_locally_used_opins). */
is_routable =
directed_search_route_net(inet, pres_fac,
router_opts.
astar_fac,
router_opts.
bend_cost, mst);
/* Impossible to route? (disconnected rr_graph) */
if(!is_routable)
{
printf("Routing failed.\n");
free(net_index);
free(sinks);
return (FALSE);
}
}
}
end = clock();
#ifdef CLOCKS_PER_SEC
printf("routing iteration took %g seconds\n", (float)(end - begin) / CLOCKS_PER_SEC);
#else
printf("routing iteration took %g seconds\n", (float)(end - begin) / CLK_PER_SEC);
#endif
fflush(stdout);
if(itry == 1) {
/* Early exit code for cases where it is obvious that a successful route will not be found
Heuristic: If total wirelength used in first routing iteration is X% of total available wirelength, exit
*/
total_wirelength = 0;
available_wirelength = 0;
for(i = 0; i < num_rr_nodes; i++) {
if(rr_node[i].type == CHANX || rr_node[i].type == CHANY)
{
available_wirelength += 1 + rr_node[i].xhigh - rr_node[i].xlow +
rr_node[i].yhigh - rr_node[i].ylow;
}
}
for(inet = 0; inet < num_nets; inet++)
{
if(clb_net[inet].is_global == FALSE && clb_net[inet].num_sinks != 0)
{ /* Globals don't count. */
get_num_bends_and_length(inet, &bends, &wirelength,
&segments);
total_wirelength += wirelength;
}
}
printf("wirelength after first iteration %d, total available wirelength %d, ratio %g\n", total_wirelength, available_wirelength, (float)(total_wirelength)/(float)(available_wirelength));
if((float)(total_wirelength)/(float)(available_wirelength) > FIRST_ITER_WIRELENTH_LIMIT) {
printf("Wirelength usage ratio exceeds limit of %g, fail routing\n", FIRST_ITER_WIRELENTH_LIMIT);
free(net_index);
free(sinks);
return FALSE;
}
}
/* Make sure any CLB OPINs used up by subblocks being hooked directly *
* to them are reserved for that purpose. */
if(itry == 1)
rip_up_local_opins = FALSE;
else
rip_up_local_opins = TRUE;
reserve_locally_used_opins(pres_fac, rip_up_local_opins,
clb_opins_used_locally);
success = feasible_routing();
if(success)
{
printf
("Successfully routed after %d routing iterations by Directed Search.\n",
itry);
free(net_index);
free(sinks);
return (TRUE);
}
#if 0
else
{
sprintf(msg,
"After iteration %d routing failed (A*) with a channel width factor of %d and Fc_int of %d, Fs_int of %d.",
itry, width_fac, Fc_int, Fs_int);
init_draw_coords(pins_per_clb);
update_screen(MAJOR, msg, ROUTING, FALSE);
}
#endif
if(itry == 1)
{
pres_fac = router_opts.initial_pres_fac;
pathfinder_update_cost(pres_fac, 0.); /* Acc_fac=0 for first iter. */
}
else
{
pres_fac *= router_opts.pres_fac_mult;
pathfinder_update_cost(pres_fac, router_opts.acc_fac);
}
}
printf("Routing failed.\n");
free(sinks);
free(net_index);
return (FALSE);
}
boolean try_breadth_first_route(struct s_router_opts router_opts,
t_ivec ** clb_opins_used_locally, int width_fac) {
/* Iterated maze router ala Pathfinder Negotiated Congestion algorithm, *
* (FPGA 95 p. 111). Returns TRUE if it can route this FPGA, FALSE if *
* it can't. */
float pres_fac;
boolean success, is_routable, rip_up_local_opins;
int itry, inet;
/* Usually the first iteration uses a very small (or 0) pres_fac to find *
* the shortest path and get a congestion map. For fast compiles, I set *
* pres_fac high even for the first iteration. */
pres_fac = router_opts.first_iter_pres_fac;
for (itry = 1; itry <= router_opts.max_router_iterations; itry++) {
for (inet = 0; inet < num_nets; inet++) {
if (clb_net[inet].is_global == FALSE) { /* Skip global nets. */
pathfinder_update_one_cost(trace_head[inet], -1, pres_fac);
is_routable = breadth_first_route_net(inet,
router_opts.bend_cost);
/* Impossible to route? (disconnected rr_graph) */
if (!is_routable) {
vpr_printf(TIO_MESSAGE_INFO, "Routing failed.\n");
return (FALSE);
}
pathfinder_update_one_cost(trace_head[inet], 1, pres_fac);
}
}
/* Make sure any CLB OPINs used up by subblocks being hooked directly *
* to them are reserved for that purpose. */
if (itry == 1)
rip_up_local_opins = FALSE;
else
rip_up_local_opins = TRUE;
reserve_locally_used_opins(pres_fac, rip_up_local_opins,
clb_opins_used_locally);
success = feasible_routing();
if (success) {
vpr_printf(TIO_MESSAGE_INFO, "Successfully routed after %d routing iterations.\n", itry);
return (TRUE);
}
if (itry == 1)
pres_fac = router_opts.initial_pres_fac;
else
pres_fac *= router_opts.pres_fac_mult;
pres_fac = std::min(pres_fac, static_cast<float>(HUGE_POSITIVE_FLOAT / 1e5));
pathfinder_update_cost(pres_fac, router_opts.acc_fac);
}
vpr_printf(TIO_MESSAGE_INFO, "Routing failed.\n");
return (FALSE);
}