def analyze_dependence(program):
program_w_attributes = assign_node_ids(program)
graph = DependenceGraph()
for (ref1, ref2) in iterate_unique_reference_pairs(program_w_attributes):
for dependence_dv in iterate_dependence_direction_vectors(ref1, ref2):
for ref1_then_ref2_dv in iterate_execution_order_direction_vector(
ref1, ref2):
logger.debug(
f'Testing:\n'
f'{ref1.pprint()} -> {ref2.pprint()}:, '
f'dep({dependence_dv}) exe_order({ref1_then_ref2_dv})')
dv1 = calculate_valid_direction_vector(dependence_dv,
ref1_then_ref2_dv)
if dv1 is not None:
logger.debug(f'Valid direction vector: {dv1}')
graph.add(ref1, ref2, dv1)
dependence_dv_inv = negate_direction_vector(dependence_dv)
for ref2_then_ref1_dv in iterate_execution_order_direction_vector(
ref2, ref1):
logger.debug(
f'Testing:\n'
f'{ref2.pprint()} -> {ref2.pprint()}:, '
f'dep({dependence_dv_inv}) exe_order({ref2_then_ref1_dv})')
dv2 = calculate_valid_direction_vector(dependence_dv_inv,
ref2_then_ref1_dv)
if dv2 is not None:
logger.debug(f'Valid direction vector: {dv2}')
graph.add(ref2, ref1, dv2)
return graph, program_w_attributes
class LoopFusion(Transform):
def pre_apply(self, fn):
self.graph = DependenceGraph()
self.graph.visit_fn(fn)
self.waiting = self.graph.nodes
self.added = set([])
self.scopes = []
def post_apply(self, fn):
if len(self.waiting) != 0:
print "Statement nodes not added:"
for stmt_node in self.waiting:
print " -- ", stmt_node
assert False, "Not all statements added back to program!"
def transform_block(self, old_stmts):
"""
Do an extremely slow and inefficient topological sort
(change this later, now just prototyping)
"""
first_iter = True
n_added = 0
scope = id(old_stmts)
self.scopes.append(scope)
new_stmts = []
while first_iter or n_added > 0:
n_added = 0
first_iter = False
for node in sorted(list(self.waiting)):
if node.id not in self.added and \
node.scope == scope and \
all(node_id in self.added or node_id == node.id
for node_id in node.depends_on):
self.waiting.remove(node)
stmt = self.transform_stmt(node.stmt)
new_stmts.append(stmt)
self.added.add(node.id)
n_added += 1
self.scopes.pop()
return new_stmts
def pre_apply(self, fn): self.graph = DependenceGraph() self.graph.visit_fn(fn) self.waiting = self.graph.nodes self.added = set([]) self.scopes = []
