A lesson in the art of JoeJITFu!
JIT-Fu is a PHP extension that exposes an OO API for the creation of native instructions to PHP userland, using libjit.
Disclaimer: the elephpant above is an artists rendition, the actual animal may or may not exist ...
Because apparently, that's super important ...
<?php
use JITFU\Context;
use JITFU\Type;
use JITFU\Signature;
use JITFU\Func;
use JITFU\Value;
$context = new Context();
$integer = Type::of(Type::int);
$function = new Func($context, new Signature($integer, [$integer]), function($args) use($integer) {
$zero = new Value($this, 0, $integer);
$one = new Value($this, 1, $integer);
$two = new Value($this, 2, $integer);
/* if ($arg == 0) return 0; */
$this->doIf(
$this->doEq($args[0], $zero),
function() use ($zero) {
$this->doReturn($zero);
}
);
/* if ($arg == 1) return 1; */
$this->doIf(
$this->doEq($args[0], $one),
function() use($one) {
$this->doReturn($one);
}
);
/* return $function($arg-1) + $function($arg-2); */
$this->doReturn(
$this->doAdd(
$this->doCall($this, [$this->doSub($args[0], $one)]),
$this->doCall($this, [$this->doSub($args[0], $two)])));
});
$function->dump("Fibonacci");
var_dump($function(40)); /* __invoke with magicalness */
?>The code above will yield something like the following output:
[joe@localhost jit]$ time php -dextension=jitfu.so objects.php
function Fibonacci(i1 : int) : int
incoming_reg(i1, rdi)
.L:
i6 = i1 == 0
if i1 != 0 then goto .L0
.L:
return_int(0)
ends_in_dead
.L0:
i7 = i1 == 1
if i1 != 1 then goto .L1
.L:
return_int(1)
ends_in_dead
.L1:
i8 = i1 - 1
outgoing_reg(i8, rdi)
call 0x08215dfd0
.L:
return_reg(i10, rax)
i12 = i1 - 2
outgoing_reg(i12, rdi)
call 0x08215dfd0
.L:
return_reg(i14, rax)
i15 = i10 + i14
return_int(i15)
ends_in_dead
.L:
.L:
end
int(102334155)
real 0m1.001s
user 0m0.997s
sys 0m0.003s
On my machine, this is ~60 times faster than PHP.
This library is not useful for compiling Zend opcodes
This extension is being developed against the latest libjit sources, it is advisable to install a fresh copy of libjit even if the system has one present:
git clone git://git.sv.gnu.org/libjit.git
cd libjit
./auto_gen.sh
./configure --prefix=/opt
make
sudo make install
Now you can build the PHP extension:
git clone https://github.com/krakjoe/jitfu
cd jitfu
phpize
./configure --with-jitfu=/opt
make
sudo make install
The example sessions above will result in a build of libjit and JIT-Fu
- integration tests for as much as possible
- bother with windows ... anyone ?
- other cool things, probably
- pecl & phpdoc