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Ich versuche mit dem neuen Spirit X3 (Boost 1.61.0) in den Griff zu bekommen.Kompiliere mal mit Boost Spirit x3
Meine Maschine ist ein MacBook Pro (i7-4750HQ) unter Linux.
Nachdem ich die Version 2 von Spirit verwendet habe, war ich an große Kompilierzeiten gewöhnt, aber das fühlt sich nicht richtig an. Für die folgenden ersten Schritte eines Ausdrucksparsers benötigt die Kompilation 20s.
Ich dachte X3 wird schneller sein, also ist das vernünftig? Ist mein Code suboptimal?
Compiler-Einstellungen (Klirren 3.8.0)
clang++ -c -pipe -std=c++14 -ftemplate-depth=512 -g -w -Wall -Wno-unused-parameter -fPIC
Code:
//#define BOOST_SPIRIT_X3_DEBUG
#include <iostream>
#include <boost/spirit/home/x3.hpp>
#include <boost/spirit/home/x3/support/ast/variant.hpp>
#include <boost/fusion/include/adapt_struct.hpp>
#include <string>
#include <vector>
//--------------------------------------------------------------------------------------------------
namespace client { namespace ast
{
namespace fusion = boost::fusion;
namespace x3 = boost::spirit::x3;
struct number : x3::variant<int, double> {
using base_type::base_type;
using base_type::operator=;
};
struct add_ast;
struct mult_ast;
struct block_ast;
struct function;
struct expr_ast : x3::variant<
number,
x3::forward_ast<function>,
x3::forward_ast<add_ast>,
x3::forward_ast<mult_ast>,
x3::forward_ast<block_ast>
> {
using base_type::base_type;
using base_type::operator=;
};
struct add_ast {
expr_ast lhs;
bool add;
expr_ast rhs;
};
struct mult_ast {
expr_ast lhs;
bool mult;
expr_ast rhs;
};
struct block_ast {
expr_ast body;
};
struct function {
std::string name;
std::vector<expr_ast> params;
};
}}
//--------------------------------------------------------------------------------------------------
BOOST_FUSION_ADAPT_STRUCT(client::ast::add_ast,
(client::ast::expr_ast, lhs),
(bool, add),
(client::ast::expr_ast, rhs)
)
BOOST_FUSION_ADAPT_STRUCT(client::ast::mult_ast,
(client::ast::expr_ast, lhs),
(bool, mult),
(client::ast::expr_ast, rhs)
)
BOOST_FUSION_ADAPT_STRUCT(client::ast::block_ast,
(client::ast::expr_ast, body)
)
BOOST_FUSION_ADAPT_STRUCT(client::ast::function,
(std::string, name),
(std::vector<client::ast::expr_ast>, params)
)
//--------------------------------------------------------------------------------------------------
namespace client { namespace parser
{
namespace x3 = boost::spirit::x3;
const x3::rule<class expr, ast::expr_ast> expr = "expr";
const x3::rule<class add_expr, ast::expr_ast> add_expr = "add_expr";
const x3::rule<class mult_expr, ast::expr_ast> mult_expr = "mult_expr";
const x3::rule<class block_expr, ast::expr_ast> block_expr = "block_expr";
auto const number = x3::rule<class number, ast::number> {"number"}
= (x3::int_ >> !x3::lit('.')) | x3::double_;
auto const fct_name = x3::rule<class fct_name, std::string> {"fct_name"}
= x3::lexeme[ *x3::alpha >> *(x3::alnum | x3::char_('_')) ];
auto const function = x3::rule<class function, ast::function> {"function"}
= fct_name >> x3::lit("(") >> -expr % ',' >> ")";
auto const simple_expr = x3::rule<class simple_expr, ast::expr_ast> {"simple_expr"}
= function | number;
auto const block_term = x3::rule<class block_term, ast::block_ast> {"block_term"}
= "(" >> expr >> ")";
auto const mult_term = x3::rule<class mult_term, ast::mult_ast> {"mult_term"}
= block_expr
>> ((x3::lit("*") >> x3::attr(true)) | (x3::lit("/") >> x3::attr(false)))
>> mult_expr;
auto const add_term = x3::rule<class add_term, ast::add_ast> {"add_term"}
= mult_expr
>> ((x3::lit("+") >> x3::attr(true)) | (x3::lit("-") >> x3::attr(false)))
>> add_expr;
auto const block_expr_def = block_term | simple_expr;
auto const mult_expr_def = mult_term | block_expr;
auto const add_expr_def = add_term | mult_expr;
auto const expr_def = add_expr;
BOOST_SPIRIT_DEFINE(expr, add_expr, mult_expr, block_expr);
}}
//--------------------------------------------------------------------------------------------------
namespace client { namespace ast
{
struct printer
{
typedef std::string result_type;
std::string operator()(const expr_ast &ast) const
{
return boost::apply_visitor(printer(), ast);
}
std::string operator()(const number &value) const
{
return boost::apply_visitor(printer(), value);
}
std::string operator()(const add_ast &expr) const {
return "(" + boost::apply_visitor(printer(), expr.lhs) + (expr.add?" + ":" - ")
+ boost::apply_visitor(printer(), expr.rhs) + ")";
}
std::string operator()(const mult_ast &expr) const {
return "(" + boost::apply_visitor(printer(), expr.lhs) + (expr.mult?" * ":"/")
+ boost::apply_visitor(printer(), expr.rhs) + ")";
}
std::string operator()(const block_ast &expr) const {
return boost::apply_visitor(printer(), expr.body);
}
std::string operator()(const function &fct) const
{
std::string result = fct.name + "(";
for (std::size_t i = 0; i < fct.params.size(); ++i) {
result += printer()(fct.params[i]);
if (i != fct.params.size() - 1)
result += ",";
}
result += ")";
return result;
}
std::string operator()(int const& value) const
{
return std::to_string(value);
}
std::string operator()(double const& value) const
{
return std::to_string(value);
}
};
}}
//--------------------------------------------------------------------------------------------------
int main()
{
std::vector<std::string> storage = {
"foo()", "-foo()",
"f1_2()",
"foo_bar()",
"foo(bar (42, baz()))",
"foo(5)", "foo(-5)",
"foo(1.1, foo(4.21e-2, 4., 6))",
"1.1", "-1.1",
"1 * 1",
"foo(1 * 1) * bar(42)",
"foo(2 + 5.5, bar()*3.4-7)",
"foo(2 + 5.5, bar(baz(-5/foo())) * 3.4 - 7)",
"4 + 5 * 6",
"1+2+3+4*5*6*-7+-8*+9-0",
"(foo())",
"foo() * ((1+2)+3*(2+3))",
"(1+2)*3", "1+2*3",
"foo"
};
using boost::spirit::x3::ascii::space;
for (const auto &item : storage) {
using client::parser::expr; // Our grammar
client::ast::expr_ast ast; // Our tree
std::string::const_iterator iter = item.begin();
std::string::const_iterator end = item.end();
bool r = phrase_parse(iter, end, expr, space, ast);
if (r && iter == end)
{
std::cout << "Ok: " << item << " result: " << client::ast::printer()(ast) << std::endl;
}
else
{
std::cout << "Fail: " << item << std::endl;
}
}
}
15s für mich auf einem modernen MacBook Pro mit -O0, 27s mit -O3. Musste 2 # includes hinzufügen, um es kompilieren zu lassen - stdexcept und exception. –
^^ das war mit Apfel klingeln. –
Obwohl Joel die Maschine nicht spezifiziert, [gibt er das Timing] (http://boost-spirit.com/home/2013/02/23/spirit-x3-on-github/) für die Kompilierung des Beispiels calc4 als ~ 5s. Ihr Beispiel scheint komplexer zu sein, also scheinen die Zeiten, die Sie sehen, nicht unangemessen.In Anbetracht dessen, was Sie für die Menge an Code bekommen, die Sie schreiben mussten (und die Menge an Arbeit, die der Compiler zu tun hat) ... –