def _compute_remove_num_envs(self, ast, new_vars, sub_env_structure):
from pycket import config
if not config.prune_env:
remove_num_envs = [0] * (len(ast.rhss) + 1)
env_structures = [sub_env_structure.prev] * len(ast.rhss)
env_structures.append(sub_env_structure)
return ast, sub_env_structure, env_structures, remove_num_envs
# find out whether a smaller environment is sufficient for the body
free_vars_not_from_let = compute_body_frees(ast, self.free_vars_cache)
free_vars_not_from_let = free_vars_not_from_let.without_many(
ast.args.elems)
# at most, we can remove all envs, apart from the one introduced by let
curr_remove = max_depth = sub_env_structure.depth_and_size()[0] - 1
max_needed = 0
free_vars_not_mutated = True
for v in free_vars_not_from_let:
depth = sub_env_structure.depth_of_var(v)[1] - 1
curr_remove = min(curr_remove, depth)
max_needed = max(max_needed, depth)
free_vars_not_mutated &= LexicalVar(v) not in new_vars
if curr_remove == 0:
body_env_structure = sub_env_structure
else:
next_structure = sub_env_structure.prev.drop_frames(curr_remove)
body_env_structure = SymList(ast.args.elems, next_structure)
if (free_vars_not_mutated and max_needed == curr_remove
and max_depth > max_needed):
before_max_needed = sub_env_structure.drop_frames(max_needed + 2)
if before_max_needed and before_max_needed.depth_and_size()[1] > 0:
counts, new_lhs_vars, new_rhss = self._copy_live_vars(
ast, free_vars_not_from_let)
body_env_structure = SymList(new_lhs_vars)
sub_env_structure = SymList(new_lhs_vars,
sub_env_structure.prev)
ast = Let(body_env_structure, counts, new_rhss, ast.body)
return self._compute_remove_num_envs(ast, new_vars,
sub_env_structure)
# The loops will modify all but the last element
remove_num_envs = [curr_remove] * (len(ast.rhss) + 1)
env_structures = [body_env_structure] * (len(ast.rhss) + 1)
for i in range(len(ast.rhss) - 1, -1, -1):
free_vars = ast.rhss[i].free_vars(self.free_vars_cache)
for v in free_vars:
var_depth = sub_env_structure.prev.depth_of_var(v)[1]
curr_remove = min(curr_remove, var_depth)
env_structures[i] = sub_env_structure.drop_frames(curr_remove + 1)
remove_num_envs[i] = curr_remove
return ast, sub_env_structure, env_structures, remove_num_envs
def _compute_remove_num_envs(self, ast, new_vars, sub_env_structure):
from pycket import config
if not config.prune_env:
remove_num_envs = [0] * (len(ast.rhss) + 1)
env_structures = [sub_env_structure.prev] * len(ast.rhss)
env_structures.append(sub_env_structure)
return ast, sub_env_structure, env_structures, remove_num_envs
# find out whether a smaller environment is sufficient for the body
free_vars_not_from_let = compute_body_frees(ast)
free_vars_not_from_let = free_vars_not_from_let.without_many(
ast.args.elems)
# at most, we can remove all envs, apart from the one introduced by let
curr_remove = max_depth = sub_env_structure.depth_and_size()[0] - 1
max_needed = 0
free_vars_not_mutated = True
for v in free_vars_not_from_let:
depth = sub_env_structure.depth_of_var(v)[1] - 1
curr_remove = min(curr_remove, depth)
max_needed = max(max_needed, depth)
free_vars_not_mutated &= LexicalVar(v) not in new_vars
if curr_remove == 0:
body_env_structure = sub_env_structure
else:
next_structure = sub_env_structure.prev.drop_frames(curr_remove)
body_env_structure = SymList(ast.args.elems, next_structure)
if (free_vars_not_mutated and max_needed == curr_remove and
max_depth > max_needed):
before_max_needed = sub_env_structure.drop_frames(max_needed + 2)
if before_max_needed and before_max_needed.depth_and_size()[1] > 0:
counts, new_lhs_vars, new_rhss = self._copy_live_vars(
ast, free_vars_not_from_let)
body_env_structure = SymList(new_lhs_vars)
sub_env_structure = SymList(new_lhs_vars, sub_env_structure.prev)
ast = Let(body_env_structure, counts, new_rhss, ast.body)
return self._compute_remove_num_envs(ast, new_vars, sub_env_structure)
# The loops will modify all but the last element
remove_num_envs = [curr_remove] * (len(ast.rhss) + 1)
env_structures = [body_env_structure] * (len(ast.rhss) + 1)
for i in range(len(ast.rhss) - 1, -1, -1):
free_vars = ast.rhss[i].free_vars()
for v in free_vars:
var_depth = sub_env_structure.prev.depth_of_var(v)[1]
curr_remove = min(curr_remove, var_depth)
env_structures[i] = sub_env_structure.drop_frames(curr_remove + 1)
remove_num_envs[i] = curr_remove
return ast, sub_env_structure, env_structures, remove_num_envs
def test_cont_fusion():
from pycket.env import SymList, ToplevelEnv
from pycket.interpreter import (
LetCont,
BeginCont,
FusedLet0Let0Cont,
FusedLet0BeginCont,
)
from pycket.config import get_testing_config
args = SymList([])
counts = [1]
rhss = 1
letast1 = Let(args, counts, [1], [2])
letast2 = Let(args, counts, [1], [2])
env = ToplevelEnv(get_testing_config(**{"pycket.fuse_conts": True}))
prev = object()
let2 = LetCont.make([], letast2, 0, env, prev)
let1 = LetCont.make([], letast1, 0, env, let2)
assert isinstance(let1, FusedLet0Let0Cont)
assert let1.prev is prev
assert let1.env is env
let2 = BeginCont(letast2.counting_asts[0], env, prev)
let1 = LetCont.make([], letast1, 0, env, let2)
assert isinstance(let1, FusedLet0BeginCont)
assert let1.prev is prev
assert let1.env is env
def visit_let(self, ast, vars, env_structure):
assert isinstance(ast, Let)
sub_env_structure = SymList(ast.args.elems, env_structure)
local_muts = self.body_muts(ast)
new_vars = vars.copy()
new_vars.update(local_muts)
ast, sub_env_structure, env_structures, remove_num_envs = self._compute_remove_num_envs(
ast, new_vars, sub_env_structure)
new_rhss = [None] * len(ast.rhss)
offset = 0
variables = ast.args.elems
need_cell_flags = [False] * len(ast.args.elems)
for i, rhs in enumerate(ast.rhss):
count = ast.counts[i]
for j in range(count):
var = variables[offset + j]
need_cell_flags[offset + j] = LexicalVar(var) in local_muts
new_rhss[i] = rhs.visit(self, vars, env_structures[i])
offset += count
body_env_structure = env_structures[-1]
body_env_structures, body_remove_num_envs = self._visit_sequenced_body(
ast, vars, body_env_structure)
new_body = [
b.visit(self, new_vars, body_env_structures[i])
for i, b in enumerate(ast.body)
]
result = Let(sub_env_structure, ast.counts, new_rhss, new_body,
remove_num_envs)
result.init_body_pruning(body_env_structure, body_remove_num_envs)
result.init_mutable_var_flags(need_cell_flags)
return result
def visit_letrec(self, ast, vars, env_structure):
assert isinstance(ast, Letrec)
local_muts = self.body_muts(ast)
for b in ast.rhss:
local_muts.update(b.mutated_vars(self.mutated_vars_cache))
for v in ast.args.elems:
lv = LexicalVar(v)
local_muts[lv] = None
new_vars = vars.copy()
new_vars.update(local_muts)
sub_env_structure = SymList(ast.args.elems, env_structure)
new_rhss = [
rhs.visit(self, new_vars, sub_env_structure) for rhs in ast.rhss
]
body_env_structures, body_remove_num_envs = self._visit_sequenced_body(
ast, new_vars, sub_env_structure)
new_body = [
b.visit(self, new_vars, body_env_structures[i])
for i, b in enumerate(ast.body)
]
letrec = Letrec(sub_env_structure, ast.counts, new_rhss, new_body)
letrec.init_body_pruning(sub_env_structure, body_remove_num_envs)
return letrec
def test_symlist_depth():
from pycket.env import SymList
s = SymList([1, 2, 3, 4], SymList([], None))
assert s.depth_and_size() == (2, 4)
def test_symlist_depth():
from pycket.env import SymList
s = SymList([1, 2, 3, 4], SymList([], None))
assert s.depth_and_size() == (2, 4)
