Did you already use built-in function in PHP like count, strlen or in_array ?
I think so, these are essential but do you know there are some of these functions that can be executed faster !? Thanks to OpCode optimized.
OpCode you said ?
Yeah OpCode, you know this is the list of instructions that are generated when your php code is compiled and easier interpreted by the computer.
For exemple this code :
<?php
namespace foo;
$myString = 'This is my string !';
strlen($myString);
Will generate this OpCode :
line #* E I O op fetch ext return operands
--------------------------------------------------------------------------------
5 0 E > ASSIGN !0, 'This+is+my+string+%21'
6 1 INIT_NS_FCALL_BY_NAME 'foo%5Cstrlen'
2 SEND_VAR_EX !0
3 DO_FCALL 0
4 > RETURN 1
And some functions like strlen has is own opCode (you can see this in the next pictures at line 6)
line #* E I O op fetch ext return operands
---------------------------------------------------------------------------
5 0 E > ASSIGN !0, 'This+is+my+string+%21'
6 1 STRLEN ~2 !0
2 FREE ~2
3 > RETURN 1
Instead of use a call to a function INIT_NS_FCALL_BY_NAME you can use the OpCode STRLEN directly that was optimized.
This OpCode is not use by default when you are in a namespace (like my exemple), if you want to use the optimized version you have to prefix your built-it function by a backslash \ like this : \strlen('foo bar').
To compare the performance of the two versions, I make a little script which use strlen in a loop with and without backslash and this is the result :
Not optimized strlen in a loop
<?php
namespace foo;
$bar = [];
for($i = 0; $i < 10000; $i++) {
$bar[] = strlen('this is my string !'.$i);
}
Optimized \strlen always in a loop
<?php
namespace foo;
$bar = [];
for($i = 0; $i < 10000; $i++) {
$bar[] = \strlen('this is my string !'.$i);
}
It's a micro optimization, but always good to take.
A list of opCode was introduced with PHP 7.0, you can see it bellow:
Most useful functions
Comparison functions
- is_null
- is_bool
- is_long
- is_int
- is_integer
- is_float
- is_double
- is_real
- is_string
- is_array
- is_object
- is_resource
- is_callable
Cast functions
- boolval
- intval
- floatval
- doubleval
- strval
Other functions
- chr
- ord
- dirname
- defined
- constant
- define
- gettype
- get_class
- get_called_class
- func_num_args
- func_get_args
- function_exists
- extension_loaded
- call_user_func_array
- call_user_func
- array_slice
If you don't like prefix your functions with a \ you can import the function with use function instead and enjoy the benefits of optimized code.
<?php
namespace foo;
use function strlen;
$myString = 'This is my string !';
strlen($myString);
You can use a tool like PHP-CS-FIXER to indicate in your code base which optimisations can be done and fix them, for optimized functions the option is native_function_invocation.
In conclusion, use the optimized functions as much as possible, it does not require much effort and can make your code more efficient.
Here is some links :
Thank you for reading,
Codeur Malin
Top comments (1)
a very nice, and quite well-hidden gem of knowledge!