def get_bipartition(
self,
direction: Dir,
max_usage_ratio: float,
max_search_time: int,
) -> Optional[Dict[Vertex, Slot]]:
"""
bi-partition all the current slots
"""
m = get_mip_model_silent()
v2var = self._create_ilp_vars(m)
self._add_opt_goal(m, v2var, direction)
# area constraints for each child slot
self._add_area_constraints(m, v2var, direction, max_usage_ratio)
self._add_pre_assignment(m, v2var, direction)
self._add_grouping_constraints(m, v2var)
m.optimize(max_seconds=max_search_time)
next_v2s = self._get_partition_result(m, v2var, direction)
if not next_v2s:
_logger.debug(
f'bi-partioning failed with usage ratio {max_usage_ratio}')
return next_v2s
def route_design(self,
routing_usage_limit: float = 0.6,
detour_path_limit: int = 4) -> Dict[Edge, List[Slot]]:
while 1:
if routing_usage_limit > 1:
_logger.error(f'Global routing failed')
exit(1)
_logger.info(
f'Global routing attempt with routing usage limit {routing_usage_limit}'
)
m = get_mip_model_silent()
fifo_to_paths = self.get_fifo_to_candidate_paths(
routing_usage_limit, detour_path_limit)
path_to_var = self.get_path_to_var(m, fifo_to_paths)
routing_edge_to_paths = self.get_routing_edge_to_passing_paths(
fifo_to_paths)
_logger.info(f'there are {len(fifo_to_paths)} dataflow edges')
_logger.info(
f'there are {len(path_to_var)} potential paths to select from')
self.constrain_fifo_to_one_path(m, fifo_to_paths, path_to_var)
self.constrain_routing_edge_capacity(m, path_to_var,
routing_edge_to_paths)
self.add_opt_goal(m, fifo_to_paths, path_to_var)
status = m.optimize()
if status == OptimizationStatus.OPTIMAL:
_logger.warning(
f'Succeeded: global routing attempt with routing usage limit {routing_usage_limit}'
)
break
else:
_logger.warning(
f'Failed: global routing attempt with routing usage limit {routing_usage_limit}'
)
routing_usage_limit += 0.03
# extract results
fifo_to_selected_path, routing_edge_to_selected_paths = \
self.get_routing_results(fifo_to_paths, path_to_var, routing_edge_to_paths)
# _logger and analysis
self.analyze_routing_results(fifo_to_paths, fifo_to_selected_path,
routing_edge_to_selected_paths)
fifo_to_slots = {
fifo: path.get_slots_in_path()
for fifo, path in fifo_to_selected_path.items()
}
return fifo_to_slots
def eight_way_partition(
init_v2s: Dict[Vertex, Slot],
grouping_constraints: List[List[Vertex]],
pre_assignments: Dict[Vertex, Slot],
slot_manager: SlotManager,
max_usage_ratio: float,
slr_width_limit: int,
max_search_time: int,
hbm_port_v_list: List[Vertex] = [],
) -> Dict[Vertex, Slot]:
m = get_mip_model_silent()
v_list = list(init_v2s.keys())
# three variables could determine the location of a module
# y = y1 *2 + y2 (four slots)
# x = x (each SLR is divided by half)
v2var_x, v2var_y1, v2var_y2 = dict(), dict(), dict()
for v in v_list:
v2var_x[v] = m.add_var(var_type=BINARY, name=f'{v.name}_x')
v2var_y1[v] = m.add_var(var_type=BINARY, name=f'{v.name}_y1')
v2var_y2[v] = m.add_var(var_type=BINARY, name=f'{v.name}_y2')
func_get_slot_by_idx = _get_slot_by_idx_closure(slot_manager)
slot_to_idx = _get_slot_to_idx(func_get_slot_by_idx)
_add_area_constraints(m, v_list, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2,
func_get_slot_by_idx=func_get_slot_by_idx, max_usage_ratio=max_usage_ratio)
_add_pre_assignment(m, v_list, slot_to_idx, pre_assignments, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2)
_add_hbm_port_constraints(m, hbm_port_v_list, slot_to_idx, pre_assignments, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2)
add_slr_0_1_crossing_constraint(m, v_list, v2var_y1, v2var_y2, slr_width_limit)
add_slr_1_2_crossing_constraint(m, v_list, v2var_y1, slr_width_limit)
add_slr_2_3_crossing_constraint(m, v_list, v2var_y1, v2var_y2, slr_width_limit)
_add_grouping_constraints(m, grouping_constraints, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2)
_add_opt_goal(m, v_list, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2)
_logger.debug(f'Start ILP solver with max usage ratio {max_usage_ratio} and max search time {max_search_time}s')
m.optimize(max_seconds=max_search_time)
next_v2s = _get_results(m, v_list, func_get_slot_by_idx, v2var_x=v2var_x, v2var_y1=v2var_y1, v2var_y2=v2var_y2)
return next_v2s
def latency_balancing(graph, fifo_to_path) -> Dict[str, int]:
name_to_edge: Dict[str, Edge] = graph.getNameToEdgeMap()
name_to_vertex: Dict[str, Vertex] = graph.getNameToVertexMap()
m = get_mip_model_silent()
# map Vertex -> "arrival time"
vertex_to_var = {}
for name, v in name_to_vertex.items():
vertex_to_var[v] = m.add_var(var_type=INTEGER, name=name)
# differential constraint for each edge
for e_name, e in name_to_edge.items():
# +1 because each FIFO by itself has 1 unit of latency
# in case the original design is not balanced
# note that additional pipelining for full_n will not lead to additional latency
# we only need to increase the grace period of almost full FIFOs by 1
# [update]: we skip the +1 for the orginial FIFO. We only take care of our own modifications
m += vertex_to_var[e.src] >= vertex_to_var[e.dst] + get_latency(
fifo_to_path[e])
m.objective = minimize(
xsum(e.width * (vertex_to_var[e.src] - vertex_to_var[e.dst])
for e in name_to_edge.values()))
status = m.optimize(max_seconds=120)
if status != OptimizationStatus.OPTIMAL and status != OptimizationStatus.FEASIBLE:
cli_logger.warning(
'Failed to balance reconvergent paths at loop level. Most likely there is a loop of streams.'
)
return {}
# get result
fifo_name_to_depth = {}
for e_name, e in name_to_edge.items():
e.added_depth_for_rebalance = int(
vertex_to_var[e.src].x - vertex_to_var[e.dst].x) - e.pipeline_level
fifo_name_to_depth[e_name] = e.depth + e.added_depth_for_rebalance
assert e.added_depth_for_rebalance >= 0
# logging
for e_name, e in name_to_edge.items():
_logger.info(
f'{e_name}: pipeline_level: {e.pipeline_level}, original depth: {e.depth}, added_depth_for_rebalance: {e.added_depth_for_rebalance}, width: {e.width} '
)
return fifo_name_to_depth
def get_legalized_v2s(orig_v2s: Dict[Vertex,
Slot], grouping_list: List[List[Vertex]],
all_slot_list: List[Slot], pre_assignments: Dict[Vertex,
Slot],
resource_usage_limit: int) -> Dict[Vertex, Slot]:
"""
adjust the floorplanning to satisfy the area requirement
"""
_logger.debug(
f'Begin legalizing the floorplan results, target resource usage limit: {resource_usage_limit}'
)
m = get_mip_model_silent()
v_list = list(orig_v2s.keys())
s_list = all_slot_list
v_to_s_to_var, s_to_v_to_var = _create_ilp_vars(m, v_list, s_list)
v_to_s_to_cost = _get_v_to_s_to_cost(v_list, s_list, orig_v2s)
_add_area_constraints(m, s_to_v_to_var, resource_usage_limit)
_add_pre_assignments(m, v_to_s_to_var, pre_assignments, all_slot_list)
_add_unique_assign_constraints(m, v_to_s_to_var)
_add_grouping_constraints(m, grouping_list, v_to_s_to_var, s_list)
_add_opt_goal(m, v_to_s_to_cost, v_to_s_to_var)
status = m.optimize()
if status != OptimizationStatus.OPTIMAL:
_logger.debug(
f'Fail to legalize the floorplan under target ratio {resource_usage_limit}'
)
return {}
new_v2s, new_s2v = _get_ilp_results(v_to_s_to_var)
_log_results(new_v2s, orig_v2s)
_logger.info('Finish legalizing the floorplan results.')
return new_v2s
