[libc] [llvm] [libc][bazel] Add BUILD targets for complex functions and tests. (PR #129618)

[Michael Jones via llvm-commits]

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@@ -0,0 +1,89 @@
+load("//libc/test:libc_test_rules.bzl", "libc_test")
+
+[
+    libc_test(
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michaelrj-google wrote:

IIRC the list of dependencies for `math_test` is just a generic list that mostly goes unused. In my opinion we should eventually remove both `math_test` and `libc_math_function` and express the explicit list of dependencies like we do for other targets. The main reason we haven't so far is that it's a pain to do and nobody's gotten around to doing it.

I don't think there's actually a reason that the `hdrs` are listed separately from `srcs`, other than the files are generally `.h` files. The math tests with `hdrs` are generally the ones where we have one header that defines the framework for a test, then each `.cpp` file just passes a function and type(s) to that macro to run the tests (e.g. [`FloorTest.h`](https://github.com/llvm/llvm-project/blob/main/libc/test/src/math/smoke/FloorTest.h)). 

Personally I prefer the list comprehension you have here to the other form, since it makes it less work to add a new function but I'll leave the final decision up to @lntue 

https://github.com/llvm/llvm-project/pull/129618