Interpretation of the underlying development principles of PHP7: Exploring the generation process of PHP bytecode and intermediate code

Interpretation of the underlying development principles of PHP7: Exploring the generation process of PHP bytecode and intermediate code

PHP is a scripting language widely used in Web development, and PHP7 It has been significantly updated and improved, and its performance has also been greatly improved. The underlying development principles are one of the key factors affecting PHP7 performance, including the PHP bytecode and intermediate code generation process. This article will explain the underlying development principles of PHP7 and reveal the generation process of PHP bytecode and intermediate code.

1. PHP Bytecode

PHP bytecode is an intermediate representation that converts PHP source code into an executable binary form. Compared with traditional interpreted languages, the introduction of PHP bytecode improves execution efficiency.

In the PHP running environment, the source code first undergoes lexical analysis and syntax analysis to form an abstract syntax tree (AST). Next, the PHP compiler converts the AST into PHP bytecode. The generated bytecode contains a series of instructions (opcode) for performing specific operations.

PHP bytecode can be cached, so there is no need to parse and compile the source code again the next time it is executed, thus significantly improving performance. PHP7 introduces the OPcache extension for caching and managing PHP bytecode.

2. Intermediate code

Intermediate code is an intermediate representation obtained by optimizing and converting AST before generating bytecode. Compared with AST, it is more abstract and machine-execution-oriented, further improving execution efficiency.

The intermediate code generation process is mainly divided into three stages: constant folding, expression merging and useless code deletion. Constant folding works by evaluating the value of a constant expression and replacing it with the corresponding constant value. Expression merging combines multiple expressions into a composite expression, reducing memory and calculation overhead. Useless code removal is through static analysis to remove code parts that will never be executed during program execution.

The generation of intermediate code can help PHP7 optimize at the underlying level, reduce redundant calculations and memory overhead, and improve execution efficiency.

3. Optimization techniques

In PHP programming, there are also some optimization techniques that can further improve the performance of the code. These include:

• Cache: Proper use of cache can reduce access to databases and other resources and speed up program execution.
• Memory management: Use memory management functions rationally, release unused memory in a timely manner, and reduce memory fragmentation.
• Reduce function calls: Too many function calls will increase the overhead of the program. Design the code structure reasonably to reduce the number of function calls.
• Concurrent processing: For a large number of concurrent requests, using concurrent processing technology can improve the response speed of the program.
• Database optimization: Optimizing database query statements and rational use of indexing and other technologies can speed up data retrieval.

To sum up, the underlying development principles of PHP7 are crucial to improving the performance of PHP programs. Understanding the generation process of PHP bytecode and intermediate code can help developers better optimize their own code and improve program execution efficiency. In addition, further application of optimization technology can further improve the performance of PHP programs and make them play a greater role in web development.

The above is the detailed content of Interpretation of the underlying development principles of PHP7: Exploring the generation process of PHP bytecode and intermediate code. For more information, please follow other related articles on the PHP Chinese website!