_builtin_expect((x),0)

__builtin_expect((x),0)是一个内置函数，用于告诉编译器一个表达式的预期结果是不太可能发生的。在这个特定的例子中，__builtin_expect((x),0)表示表达式x的预期结果是0，即不太可能为真。这个宏定义通常用于优化代码的分支预测，以提高程序的性能。\[1\]\[2\]\[3\]
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- *1* *2* [《C语言杂记》编译优化之__builtin_expect](https://blog.csdn.net/u013162035/article/details/120682680)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^insert_down1,239^v3^insert_chatgpt"}} ] [.reference_item]
- *3* [__builtin_expect用法](https://blog.csdn.net/jinbc/article/details/123589096)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^insert_down1,239^v3^insert_chatgpt"}} ] [.reference_item]
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