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faster: Significant performance boost on large grammar

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15s to 5s
This commit is contained in:
John Doty 2024-04-17 23:25:15 -07:00
parent 6fa89a9757
commit f656dbd8f3
2 changed files with 31 additions and 17 deletions
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6
grammar.py
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@ -419,7 +419,7 @@ grammar = {
# dump_yacc(grammar)
grammar, precedence = desugar(grammar, precedence)
gen = parser_faster.GenerateLR1("File", grammar, precedence=precedence)
table = gen.gen_table()
print(parser_faster.format_table(gen, table))
print()
gen.gen_table()
# print(parser_faster.format_table(gen, table))
# print()
# tree = parse(table, ["id", "+", "(", "id", "[", "id", "]", ")"])

42
parser_faster.py
View file

@ -10,6 +10,7 @@ It also supports precedence.
import collections
import dataclasses
import enum
import functools
import typing
@ -516,7 +517,7 @@ class GenerateLR0(object):
self.start_symbol = start_symbol
self.end_symbol = end_symbol
@functools.cache
def gen_closure_next(self, config: Configuration):
"""Return the next set of configurations in the closure for
config.
@ -547,14 +548,20 @@ class GenerateLR0(object):
"""
closure = set()
pending = list(seeds)
pending_next = []
while len(pending) > 0:
config = pending.pop()
if config in closure:
continue
for config in pending:
if config in closure:
continue
closure.add(config)
for next_config in self.gen_closure_next(config):
pending.append(next_config)
closure.add(config)
for next_config in self.gen_closure_next(config):
pending_next.append(next_config)
temp = pending
pending = pending_next
pending_next = temp
pending_next.clear()
return tuple(sorted(closure)) # TODO: Why tuple?
@ -596,14 +603,20 @@ class GenerateLR0(object):
successors = []
pending = [config_set]
pending_next = []
while len(pending) > 0:
config_set = pending.pop()
for config_set in pending:
id, is_new = result.register_config_set(config_set)
if is_new:
for symbol, successor in self.gen_all_successors(config_set):
successors.append((id,symbol,successor))
pending_next.append(successor)
id, is_new = result.register_config_set(config_set)
if is_new:
for symbol, successor in self.gen_all_successors(config_set):
successors.append((id,symbol,successor))
pending.append(successor)
temp = pending
pending = pending_next
pending_next = temp
pending_next.clear()
for id,symbol,successor in successors:
result.add_successor(id, symbol, result.config_set_key[successor])
@ -940,6 +953,7 @@ class GenerateLR1(GenerateSLR1):
In an LR1 parser, this is the lookahead of the configuration."""
return config.lookahead
@functools.cache
def gen_closure_next(self, config: Configuration):
"""Return the next set of configurations in the closure for
config.
@ -967,7 +981,7 @@ class GenerateLR1(GenerateSLR1):
lookahead = tuple(sorted(lookahead))
next.append(Configuration.from_rule(config_next, rule, lookahead=lookahead))
return tuple(next)
return tuple(sorted(next))
def gen_all_sets(self):
"""Generate all of the configuration sets for the grammar.