The common subexpression elimination (CSE) pass in compilers takes care of that.
Compilers cannot do this optimization for floating point [1] unless you're compiling with -ffast-math. In general, don't rely on compilers to optimize floating point sub-expressions.
[1]: https://godbolt.org/z/8bEjE9Wxx
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Compilers cannot do this optimization for floating point [1] unless you're compiling with -ffast-math. In general, don't rely on compilers to optimize floating point sub-expressions.
[1]: https://godbolt.org/z/8bEjE9Wxx