Compiler Explorer：包含各平台、各个版本、各大主流编译器。可以编译查看生成的汇编代码以及执行查看结果。
C++ Insights：
可以查看编译后的等效的C++代码，直观感受编译器会对代码做什么改变
C++ Insights is a clang-based tool which does a source to source transformation. Its goal is to make things visible, which normally and intentionally happen behind the scenes. It's about the magic the compiler does for us to make things work. Or looking through the classes of a compiler.
C++ Benchmark：
Benchmark就是做性能测试
三个网站里面也可以带着代码互相跳转。