This is one more follow-up to PR https://github.com/llvm/llvm-project/pull/157517 that cleans up the usage of libc_errno in math unit-tests (non-smoke). It follows the same rule: * if you use libc_errno in code literally, include src/__support/libc_errno.h * if you only rely on errno constants, include hdr/errno_macros.h Several tests for exp/log still retain the direct libc_errno usage, since in some cases they skip doing any validation if the error was raised. But the direct usage of libc_errno is removed from all other cases.
https://github.com/llvm/llvm-project/issues/149993
This is the first step in preparation for: https://discourse.llvm.org/t/rfc-make-clang-builtin-math-functions-constexpr-with-llvm-libc-to-support-c-23-constexpr-math-functions/86450
Fix #98393
Context: https://github.com/llvm/llvm-project/pull/87017 - Add proxy header `libc/hdr/math_macros.h` that will: - include `<math.h>` in overlay mode, - include `"include/llvm-libc-macros/math-macros.h"` in full build mode. - Its corresponding CMake target `libc.hdr.math_macros` will only depend on `libc.include.math` and `libc.include.llvm-libc-macros.math_macros` in full build mode. - Replace all `#include "include/llvm-libc-macros/math-macros.h"` with `#include "hdr/math_macros.h"`. - Add dependency to `libc.hdr.math_macros` CMake target when using `add_fp_unittest`. - Update the remaining dependency. - Update bazel overlay: add `libc:hdr_math_macros` target, and replacing all dependency on `libc:llvm_libc_macros_math_macros` with `libc:hdr_math_macros`.
Reland of #84991 A downstream overlay mode user ran into issues with the isnan macro not working in our sources with a specific libc configuration. This patch replaces the last direct includes of math.h with our internal math_macros.h, along with the necessary build system changes.
Having libc_errno outside of the namespace causes versioning issues when trying to link the tests against LLVM-libc. Most of this patch is just moving libc_errno inside the namespace in tests. This isn't necessary in the function implementations since those are already inside the namespace.
The semantics for casting can range from "bitcast" (same representation) to "different representation", to "type promotion". Here we remove the cast operator and force usage of `get_val` as the only function to get the floating point value, making the intent clearer and more consistent.