Is the strstr () function of php highly efficient? What should I do?

Is the strstr () function of php highly efficient? I am a newbie. I want to use a project that matches strings. the efficiency requirement is high. is the strstr algorithm in php highly efficient? Is kmp algorithm used in it? Is the Sunday algorithm used ?, I only know that php built-in functions are okay. Do you want to use UDFs ?, Str * class functions are generally faster than regular expressions ., Is it highly efficient to search for strstr () functions that require php words?
I am a newbie. I want to use a project that matches strings. the efficiency requirement is high. is the strstr algorithm in php highly efficient? Is kmp algorithm used in it? Is the Sunday algorithm used?

------ Solution --------------------
I only know that php built-in functions are okay. Do you want to use UDFs?
------ Solution --------------------
Str * class functions are generally faster than regular expressions.
------ Solution --------------------
It is highly efficient to use strstr to search and obtain strings. You only need to find the existence or not and do not need to get the string. strpos is the most efficient.
------ Solution --------------------
String lookup functions must be more efficient than regular classes. This strstr () is very efficient. This function is binary secure.
------ Solution --------------------
It is not clear about the internal implementation algorithm of strstr, but you can view the source code of this function.
Unless you write in c, the user-defined function cannot be higher than the built-in function.